U.S. patent application number 10/304665 was filed with the patent office on 2003-07-31 for male anti-fertility agents.
This patent application is currently assigned to Allergan Sales, Inc.. Invention is credited to Chandraratna, Roshantha A., Klein, Elliott S., Yuan, Yang-Dar.
Application Number | 20030144256 10/304665 |
Document ID | / |
Family ID | 26800542 |
Filed Date | 2003-07-31 |
United States Patent
Application |
20030144256 |
Kind Code |
A1 |
Klein, Elliott S. ; et
al. |
July 31, 2003 |
Male anti-fertility agents
Abstract
Methods and compositions for inhibiting or preventing
spermatogenesis in a male mammal. Also disclosed are compounds and
formulations for use in such methods.
Inventors: |
Klein, Elliott S.; (Marina
Del Rey, CA) ; Yuan, Yang-Dar; (Irvine, CA) ;
Chandraratna, Roshantha A.; (Laguna Hills, CA) |
Correspondence
Address: |
Carlos A. Fisher- T2-7H
ALLERGAN, INC.
2525 Dupont Drive
Irvine
CA
92623
US
|
Assignee: |
Allergan Sales, Inc.
|
Family ID: |
26800542 |
Appl. No.: |
10/304665 |
Filed: |
November 25, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10304665 |
Nov 25, 2002 |
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09591253 |
Jun 9, 2000 |
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6521641 |
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09591253 |
Jun 9, 2000 |
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09405748 |
Sep 27, 1999 |
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60103507 |
Oct 8, 1998 |
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Current U.S.
Class: |
514/150 ;
514/252.01; 514/252.03; 514/252.04; 514/255.05; 514/256; 514/311;
514/314; 514/337; 514/365; 514/372; 514/397; 514/406; 514/432;
514/456; 514/63 |
Current CPC
Class: |
A61K 31/353 20130101;
A61K 31/203 20130101; A61K 31/195 20130101; A61K 31/695 20130101;
A61K 31/00 20130101; A61K 31/47 20130101; A61P 15/16 20180101; A61K
31/196 20130101; A61K 31/192 20130101; Y10S 514/841 20130101; A61K
31/382 20130101 |
Class at
Publication: |
514/150 ;
514/311; 514/456; 514/432; 514/252.01; 514/252.03; 514/252.04;
514/255.05; 514/256; 514/365; 514/372; 514/397; 514/314; 514/63;
514/337; 514/406 |
International
Class: |
A61K 031/695; A61K
031/655; A61K 031/506; A61K 031/501; A61K 031/497; A61K 031/4709;
A61K 031/47; A61K 031/4436; A61K 031/427; A61K 031/422; A61K
031/4178; A61K 031/416; A61K 031/382; A61K 031/353 |
Claims
What is claimed is:
1. A method for inhibiting the ability of a male mammal to conceive
progeny, comprising: regularly administering to said male mammal an
effective amount of an RAR antagonist or inverse agonist for a
period of time effective to sufficiently reduce or eliminate
spermatozoa in the semen of said male mammal.
2. The method of claim 1 wherein said RAR antagonist or inverse
agonist has the chemical structure: 17wherein X is S, O, NR' where
R' is H or alkyl of 1 to 6 carbons, or X is
[C(R.sub.1).sub.2].sub.n where R.sub.1 is independently H or alkyl
of 1 to 6 carbons, and n is an integer between, and including, 0
and 2, and; R.sub.2 is independently hydrogen, lower alkyl of 1 to
6 carbons, F, Cl, Br, I, CF.sub.3, fluoro substituted alkyl of 1 to
6 carbons, OH, SH, alkoxy of 1 to 6 carbons, or alkylthio of 1 to 6
carbons, and; R.sub.3 is independently hydrogen, lower alkyl of 1
to 6 carbons or F, and; m is an integer having the value of 0-3,
and; o is an integer having the value of 0-3, and; Z is
--C.dbd.C--, --N.dbd.N--, --N.dbd.CR.sub.1--, --CR.sub.1.dbd.N,
--(CR.sub.1.dbd.CR.sub.1).sub.n'-- where n' is an integer having
the value 0-5, --CO--NR.sub.1--, --CS--NR.sub.1--, --NR--1--CO,
--NR--1--CS, --COO--, --OCO--; --CSO--; --OCS--; Y is a phenyl or
naphthyl group, or heteroaryl selected from a group consisting of
pyridyl, thienyl, furyl, pyridazinyl, pyrimidinyl, pyrazinyl,
thiazolyl, oxazolyl, imidazolyl and pyrrazolyl, said phenyl and
heteroaryl groups being optionally substituted with one or two
R.sub.2 groups, or when Z is --(CR.sub.1.dbd.CR.sub.1).sub.n'-- and
n' is 3, 4 or 5 then Y represents a direct valence bond between
said (CR.sub.2.dbd.CR.sub.2).sub.n' group and B; A is
(CH.sub.2).sub.q where q is 0-5, lower branched chain alkyl having
3-6 carbons, cycloalkyl having 3-6 carbons, alkenyl having 2-6
carbons and 1 or 2 double bonds, alkynyl having 2-6 carbons and 1
or 2 triple bonds; B is hydrogen, COOH or a pharmaceutically
acceptable salt thereof, COOR.sub.8, CONR.sub.9R.sub.10,
--CH.sub.2OH, CH.sub.2OR.sub.11, CH.sub.2OCOR.sub.11, CHO,
CH(OR.sub.12).sub.2, CHOR.sub.13O, --COR.sub.7,
CR.sub.7(OR.sub.12).sub.2, CR.sub.7OR.sub.13O, or tri-lower
alkylsilyl, where R.sub.7 is an alkyl, cycloalkyl or alkenyl group
containing 1 to 5 carbons, R.sub.8 is an alkyl group of 1 to 10
carbons or trimethylsilylalkyl where the alkyl group has 1 to 10
carbons, or a cycloalkyl group of 5 to 10 carbons, or R.sub.8 is
phenyl or lower alkylphenyl, R.sub.9 and R.sub.10 independently are
hydrogen, an alkyl group of 1 to 10 carbons, or a cycloalkyl group
of 5-10 carbons, or phenyl or lower alkylphenyl, R.sub.11 is lower
alkyl, phenyl or lower alkylphenyl, R.sub.12 is lower alkyl, and
R.sub.13 is divalent alkyl radical of 2-5 carbons, and R.sub.14 is
(R.sub.15).sub.r-phenyl, (R.sub.15).sub.r-naphthyl, or
(R.sub.15).sub.r-heteroaryl where the heteroaryl group has 1 to 3
heteroatoms selected from the group consisting of O, S and N, r is
an integer having the values of 0-5, and R.sub.15 is independently
H, F, Cl, Br, I, NO.sub.2, N(R.sub.8).sub.2, N(R.sub.8)COR.sub.8,
NR.sub.8CON(R.sub.8).sub.2, OH, OCOR.sub.8, OR.sub.8, CN, an alkyl
group having 1 to 10 carbons, fluoro substituted alkyl group having
1 to 10 carbons, an alkenyl group having 1 to 10 carbons and 1 to 3
double bonds, alkynyl group having 1 to 10 carbons and 1 to 3
triple bonds, or a trialkylsilyl or trialkylsilyloxy group where
the alkyl groups independently have 1 to 6 carbons.
3. The method of claim 1 wherein said RAR antagonist or inverse
agonist has the chemical structure: 18wherein X is S, O, NR' where
R' is H or alkyl of 1 to 6 carbons, or X is [C(R).sub.2].sub.n
where R.sub.1 is independently H or alkyl of 1 to 6 carbons, and n
is an integer between, and including, 0 and 2, and; R.sub.2 is
independently hydrogen, lower alkyl of 1 to 6 carbons, F, Cl, Br,
I, CF.sub.3, fluoro substituted alkyl of 1 to 6 carbons, OH, SH,
alkoxy of 1 to 6 carbons, or alkylthio of 1 to 6 carbons, and;
R.sub.3 is independently hydrogen, lower alkyl of 1 to 6 carbons or
F, and; m is an integer having the value of 0, 1, 2, or 3, and; o
is an integer having the value of 0, 1, 2, or 3, and; Y is a phenyl
or naphthyl group, or heteroaryl selected from a group consisting
of pyridyl, thienyl, furyl, pyridazinyl, pyrimidinyl, pyrazinyl,
thiazolyl, oxazolyl, imidazolyl and pyrrazolyl, said phenyl and
heteroaryl groups being optionally substituted with one or two
R.sub.2 groups, and; A is (CH.sub.2).sub.q where q is 0-5, lower
branched chain alkyl having 3-6 carbons, cycloalkyl having 3-6
carbons, alkenyl having 2-6 carbons and 1 or 2 double bonds,
alkynyl having 2-6 carbons and 1 or 2 triple bonds, and; B is
hydrogen, COOH or a pharmaceutically acceptable salt thereof,
COOR.sub.8, CONR.sub.9R.sub.10, --CH.sub.2OH, CH.sub.2OR.sub.11,
CH.sub.2OCOR.sub.11, CHO, CH(OR.sub.12).sub.2, CHOR.sub.13O,
--COR.sub.7, CR.sub.7(OR.sub.12).sub.2, CR.sub.7OR.sub.13O, or
tri-lower alkylsilyl, where R.sub.7 is an alkyl, cycloalkyl or
alkenyl group containing 1 to 5 carbons, R.sub.8 is an alkyl group
of 1 to 10 carbons or trimethylsilylalkyl where the alkyl group has
1 to 10 carbons, or a cycloalkyl group of 5 to 10 carbons, or
R.sub.8 is phenyl or lower alkylphenyl, R.sub.9 and R.sub.10
independently are hydrogen, an alkyl group of 1 to 10 carbons, or a
cycloalkyl group of 5-10 carbons, or phenyl or lower alkylphenyl,
R.sub.11 is lower alkyl, phenyl or lower alkylphenyl, R.sub.12 is
lower alkyl, and R.sub.13 is divalent alkyl radical of 2-5 carbons,
and; R.sub.14 is (R.sub.15).sub.r-phenyl,
(R.sub.15).sub.r-naphthyl, or (R.sub.15).sub.r-heteroaryl where the
heteroaryl group has 1 to 3 heteroatoms selected from the group
consisting of O, S and N, r is an integer having the values of 0,
1, 2, 3, 4 or 5, and; R.sub.15 is independently H, F, Cl, Br, I,
NO.sub.2, N(R.sub.8).sub.2, N(R.sub.8)COR.sub.8,
NR.sub.8CON(R.sub.8).sub.2, OH, OCOR.sub.8, OR.sub.8, CN, an alkyl
group having 1 to 10 carbons, fluoro substituted alkyl group having
1 to 10 carbons, an alkenyl group having 1 to 10 carbons and 1 to 3
double bonds, alkynyl group having 1 to 10 carbons and 1 to 3
triple bonds, or a trialkylsilyl or trialkylsilyloxy group where
the alkyl groups independently have 1 to 6 carbons, and; R.sub.16
is H, lower alkyl of 1 to 6 carbons, and; R.sub.17 is H, lower
alkyl of 1 to 6 carbons, OH or OCOR.sub.11, and; p is zero or 1,
with the proviso that when p is 1 then there is no R.sub.17
substituent group, and m is an integer between, and including, 0
and 2.
4. The method of claim 1 wherein said RAR antagonist or inverse
agonist has the chemical structure: 19where X is C(R.sub.1).sub.2
or O, and; R.sub.1 is H or alkyl of 1 to 6 carbons, and; R.sub.2 is
independently lower alkyl of 1 to 6 carbons, F, Cl, Br, I,
CF.sub.3, fluoro substituted alkyl of 1 to 6 carbons, OH, SH,
alkoxy of 1 to 6 carbons, or alkylthio of 1 to 6 carbons, and; m is
an integer having the value of 0-3, and; R.sub.3 is independently
lower alkyl of 1 to 6 carbons or F, and; o is an integer having the
value of 0-3, and; s is an integer having the value of 1-3, and;
R.sub.8 is an alkyl group of 1 to 10 carbons or trimethylsilylalkyl
where the alkyl group has 1 to 10 carbons, or a cycloalkyl group of
5 to 10 carbons, or R.sub.8 is phenyl or lower alkylphenyl, and;
R.sub.15 is independently H, F, Cl, Br, I, NO.sub.2,
N(R.sub.8).sub.2, COR.sub.8, NR.sub.8CON(R.sub.8).sub.2,
OCOR.sub.8, OR.sub.8, CN, an alkyl group having 1 to 10 carbons,
fluoro substituted alkyl group having 1 to 10 carbons, an alkenyl
group having 1 to 10 carbons and 1 to 3 double bonds, an alkynyl
group having 1 to 10 carbons and 1 to 3 triple bonds, or a
trialkylsilyl or trialkylsilyloxy group where the alkyl groups
independently have 1 to 6 carbons, and; t is an integer having the
values of 0, 1, 2, 3, 4, or 5, and; the CONH group is in the 6 or 7
position of the benzopyran, and in the 2 or 3 position of the
dihydronaphthaline ring, or a pharmaceutically acceptable salt of
said compound.
5. The method of claim 1 wherein said RAR antagonist or inverse
agonist has the chemical structure: 20where X is C(CH.sub.3).sub.2
or O, and; R.sub.2 is H or Br, and; R.sub.2' and R.sub.2"
independently are H or F, and; R.sub.3 is H or CH.sub.3, and;
R.sub.8 is H, lower alkyl of 1 to 6 carbons, or a pharmaceutically
acceptable salt of said compound.
6. The method of claim 1 wherein said RAR antagonist or inverse
agonist has the chemical structure: 21wherein X.sub.1 is:
--C(R.sub.1).sub.2--, --C(R.sub.1).sub.2--C(R.sub.1).sub.2--,
--S--, --O--, --NR.sub.1--, --C(R.sub.1).sub.2--O--,
--C(R.sub.1)--S--, or C(R.sub.1)--NR.sub.1--; and R.sub.1 is
independently H or alkyl of 1 to 6 carbons; and R.sub.2 is optional
and is independently defined as lower alkyl of 1 to 6 carbons, F,
Cl, Br, I, CF.sub.3, fluoro substituted alkyl of 1 to 6 carbons, OH
SH, alkoxy of 1 to 6 carbons, or alkylthio of 1 to 6 carbons; and m
is an integer between, and including, 0 and 4; and n is an integer
between, and including, 0 and 2; and o is an integer between, and
including, 0 and 3; and R.sub.3 is H, lower alkyl of 1 to 6
carbons, F, Cl, Br or I; and R.sub.4 is (R.sub.5).sub.p-phenyl,
(R.sub.5).sub.p-naphthyl, (R.sub.5).sub.p-heteroaryl where the
heteroaryl group is five-membered or 6-membered and has 1 to 3
heteroatoms selected from the group consisting of O, S, and N; and
p is an integer between, and including, 0 and 5; and R.sub.5 is
optional and is defined as independently F, Cl, Br, I, NO.sub.2,
N(R.sub.8).sub.2, N(R.sub.8)COR.sub.8, N(R.sub.8)CON(R.sub.8).s-
ub.2, OH, OCOR.sub.8, OR.sub.8, CN, COOH, COOR.sub.8, an alkyl
group having from 1 to 10 carbons, an alkenyl group having from 1
to 10 carbons and 1 to three double bonds, alkynyl group having
from 1 to 10 carbons and 1 to 3 triple bonds, or a (trialkyl)silyl
or (trialkyl)silyloxy group where the alkyl groups independently
have from 1 to 6 carbons; and Y is a phenyl or naphthyl group, or a
heteroaryl selected from the group consisting of pyridyl, thienyl,
furyl, pyridazinyl, pyrimidinyl, pyrazinyl, thiazolyl, oxazolyl,
imidazolyl and pyrrazolyl, said phenyl and heteroaryl groups being
optionally substituted with one or two R.sub.2 groups, or Y is
--(CR.sub.3.dbd.CR.sub.3).sub.r--; and r is an integer between, and
including, 1 and 3; and A is (CH.sub.2).sub.q where q is an integer
from 0-5, lower branched chain alkyl having from 3 to 6 carbons,
cycloalkyl having from 3 to 6 carbons, alkenyl having from 2 to 6
carbons and 1 or 2 double bonds, alkenyl having from 2 to 6 carbons
and 1 or 2 triple bonds, with the proviso that when Y is
--(CR.sub.3.dbd.CR.sub.3).sub.r-- then A is (CH.sub.2).sub.q and q
is 0; and B is H, COOH or a pharmaceutically acceptable salt
thereof, COOR.sub.8, CONR.sub.9R.sub.10,--CH.sub.2OH,
CH.sub.2OR.sub.11, CH.sub.2OCOR.sub.11, CHO, CH(OR.sub.12).sub.2,
CHOR.sub.13O, --COR.sub.7, CR.sub.7(OR.sub.12).sub.2,
CR.sub.7OR.sub.13O, or Si(C.sub.1-6alkyl).sub.- 3, wherein R.sub.7
is an alkyl, cycloalkyl or alkenyl group containing 1 to 5 carbons,
R.sub.8 is an alkyl group of 1 to 10 carbons or
(trimethylsilyl)alkyl, where the alkyl groups has 1 to 10 carbons,
or a cycloalkyl group of 5 to 10 carbons, or R.sub.8 is phenyl or
lower alkylphenyl, R.sub.8 and R.sub.10 independently are H, a
lower alkyl group of 1 to 10 carbons, or a cycloalkyl group of 5-10
carbons, or phenyl or lower alkylphenyl, R.sub.11 is lower alkyl,
phenyl or lower alkylphenyl, R.sub.12 is lower alkyl, and R.sub.13
is a divalent alkyl radical of 2-5 carbons.
7. The method of claim 1 wherein said RAR antagonist or inverse
agonist has the chemical structure: 22where X.sub.1 is S or O;
X.sub.2 is CH or N; R.sub.2 is H, F, CF.sub.3 or alkoxy of 1 to 6
carbons; R.sub.2* is H, F, or CF.sub.3; R.sub.8 is H, or lower
alkyl of 1 to 6 carbons; R.sub.14 is unsubstituted phenyl, thienyl
or pyridyl, or phenyl, thienyl or pyridyl substituted with one to
three R.sub.15 groups, where R.sub.15 is lower alkyl of 1 to 6
carbons, chlorine, CF.sub.3, or alkoxy of 1 to 6 carbons, or a
pharmaceutically acceptable salt of said compound.
8. The method of claim 1 wherein said RAR antagonist or inverse
agonist has the chemical structure: 23wherein X.sub.2 is CH or N,
and; R.sub.2 is H, F, or OCH.sub.3, and; R.sub.2* is H or F, and;
R.sub.8 is H, or lower alkyl of 1 to 6 carbons, and; R.sub.41 is
selected from the group consisting of phenyl,
4-(lower-alkyl)phenyl, 5-(lower alkyl)-2-thienyl, and 6-(lower
alkyl)-3-pyridyl where lower alkyl has 1 to 6 carbons, or a
pharmaceutically acceptable salt of said compound.
9. The method of claim 1 wherein said RAR antagonist or inverse
agonist has the chemical structure: 24where R.sub.2* is H or F;
R.sub.8 is H, or lower alkyl of 1 to 6 carbons, and R.sub.14 is
selected from the group consisting of phenyl, and
4-(lower-alkyl)phenyl, where lower alkyl has 1 to 6 carbons, or a
pharmaceutically acceptable salt of said compound.
10. The method of claim 1 wherein said RAR antagonist or inverse
agonist has the chemical structure: 25where R.sub.8 is H, lower
alkyl of 1 to 6 carbons, or a pharmaceutically acceptable salt of
said compound.
11. The method of claim 1 wherein the RAR antagonist or inverse
agonist has the chemical structure: 26where R.sub.8 is H, lower
alkyl of 1 to 6 carbons, or a pharmaceutically acceptable salt of
said compound.
12. The method of claim 1 wherein said RAR antagonist or inverse
antagonist has the chemical structure:
Y.sub.3(R.sub.4)--X--Y.sub.1(R.sub-
.1R.sub.2-Z-Y.sub.2(R.sub.2)-A-B Where Y.sub.1 is phenyl, naphthyl,
or heteroaryl selected from the group consisting of pyridyl,
thienyl, furyl, pyridazinyl, pyrimidinyl, pyrazinyl, thiazonyl,
ozazolyl, imidazolyl, and pyrrazolyl, said phenyl, naphthyl, and
heteroaryl groups being substituted with an R.sub.1 group, and
further substituted or unsubstituted with one or two R.sub.2
groups; R.sub.1 is C.sub.1-10 alkyl, 1-ademantyl,
2-tetrahydropyranoxy, trialkylsilanyloxy where alkyl has up to 6
carbons, OH, alkoxy where the alkyl group has up to 10 carbons,
alkylthio where the alkyl group has up to 10 carbons, or
OCH.sub.2OC.sub.1-6 alkyl; R.sub.2 is lower alkyl of 1 to 6
carbons, F, Cl, Br, I, CF.sub.3, CF.sub.2CF.sub.3, OH, OR.sub.3,
NO.sub.2, N(R.sub.3).sub.2, CN, N.sub.3, COR.sub.3, NHCOR.sub.3,
COOH, or COOR.sub.3; X is (C(R.sub.3).sub.2, S, SO, SO.sub.2, O or
NR.sub.3; Z is --C.ident.C--, --N.dbd.N--, --N(O).dbd.N --,
--N.dbd.N(O)--, --N.dbd.CR.sub.3--, --CR.sub.3.dbd.N,
--(CR.sub.3.dbd.CR.sub.3).sub.n-- where n is an integer having the
value 0-5, --CO--NR.sub.3--, --CS--NR.sub.3--, --NR.sub.3--CO,
--NR.sub.3--CS, --COO--, --OCO--; --CSO--; --OCS--; or
--CO--CR.sub.3.dbd.R.sub.3--O, R.sub.3 is independently H or lower
alkyl of 1 to 6 carbons; Y.sub.2 is a phenyl or naphthyl group, or
heteroaryl selected from a group consisting of pyridyl, thienyl,
furyl, pyridazinyl, pyrimidinyl, pyrazinyl, thiazolyl, oxazolyl,
imidazolyl and pyrrazolyl, said phenyl, naphthyl and heteroaryl
groups being unsubstituted or substituted with one or two R.sub.2
groups, or when Z is --(CR.sub.3.dbd.CR.sub.3).sub.n-- and n is 3,
4 or 5 then Y.sub.2 represents a direct valence bond between said
--(CR.sub.3.dbd.CR.sub.3).sub.n group and B; Y.sub.3 is phenyl,
naphthyl, or heteroaryl selected from a group consisting of
pyridyl, thienyl, furyl, pyridazinyl, pyrimidinyl, pyrazinyl,
thiazolyl, oxazolyl, imidazolyl and pyrrazolyl, said phenyl,
naphthyl and heteroaryl groups being unsubstituted or substituted
with one to three R.sub.4 groups, where R.sub.4 is alkyl of 1 to 10
carbons, fluoro-substituted alkyl of 1 to 10 carbons, alkenyl of 2
to 10 carbons and having 1 to 3 triple bonds, F, Cl, Br, I,
NO.sub.2, CN, NR.sub.3, N.sub.3, COOH, COOC.sub.1-6alkyl, OH, SH,
OC.sub.1-6alkyl, and SC.sub.1-6alkyl; A is (CH.sub.2).sub.q where q
is from 0-5, lower branched alkyl having 3-6 carbons, cycloalkyl
having 3-6 carbons, alkenyl, having 2-6 carbons and 1-2 double
bonds, alkynyl having 2-6 carbons and 1 to 2 triple bonds, and B is
hydrogen, COOH or a pharmaceutically acceptable salt thereof,
COOR.sub.8, CONR.sub.9R.sub.10, --CH.sub.2OH, CH.sub.2OR.sub.11,
CH.sub.2OCOR.sub.11, CHO, CH(OR.sub.12).sub.2, CHOR.sub.13O,
--COR.sub.7, CR.sub.7(OR.sub.12).sub.2- , CR.sub.7OR.sub.13O, or
Si(C.sub.1-6 alkyl).sub.3, where R.sub.7 is an alkyl, cycloalkyl or
alkenyl group containing 1 to 5 carbons, R.sub.8 is an alkyl group
of 1 to 10 carbons or trimethylsilylalkyl where the alkyl group has
1 to 10 carbons, or a cycloalkyl group of 5 to 10 carbons, or
R.sub.8 is phenyl or lower alkylphenyl, R.sub.9 and R.sub.10
independently are hydrogen, an alkyl group of 1 to 10 carbons, or a
cycloalkyl group of 5-10 carbons, or phenyl or lower alkylphenyl,
R.sub.11 is lower alkyl, phenyl or lower alkylphenyl, R.sub.12 is
lower alkyl, and R.sub.13 is divalent alkyl radical of 2-5 carbons,
or a pharmaceutically acceptable salt of said compound.
13. The method of claim 1 wherein said RAR antagonist or inverse
agonist has the chemical structure: 27where n is an integer from 1
to 10.
14. The method of claim 1 wherein said RAR antagonist or inverse
agonist has the chemical structure: 28where n is an integer from 1
to 10.
15. The method of claim 1 wherein said RAR antagonist or inverse
agonist has the chemical structure: 29
16. The method of claim 1 wherein said RAR antagonist or inverse
agonist has the chemical structure: 30
17. The method of claim 1 wherein said RAR antagonist or inverse
agonist has the chemical structure: 31
18. The method of claim 1 wherein said period of time is thirty
days or more.
19. The method of claim 1 wherein said RAR antagonist or inverse
agonist is administered daily.
20. The method of claim 1 wherein said RAR antagonist or inverse
agonist is administered orally.
21. The method of claim 1 wherein said RAR antagonist or inverse
agonist is administered topically.
22. The method of claim 1 wherein said RAR antagonist or inverse
agonist inhibits transcriptional activation of two or less retinoic
acid receptors selected from the group consisting of: a) an
RAR.alpha. receptor; b) an RAR.beta. receptor; and c) an RAR.gamma.
receptor.
23. A method for inhibiting spermatogenesis in a male mammal,
comprising: administering to said male mammal an effective amount
of a composition comprising an RAR antagonist or inverse agonist
over a period of time effective to prevent conception.
24. A contraceptive effective to inhibit spermatogenesis in a male
mammal comprising: a) an RAR antagonist or inverse agonist, and b)
a pharmaceutically acceptable excipient.
25. The contraceptive of claim 24, wherein said RAR antagonist or
inverse agonist has the structure: 32wherein X is S, O, NR' where
R' is H or alkyl of 1 to 6 carbons, or X is
[C(R.sub.1).sub.2].sub.n where R.sub.1 is independently H or alkyl
of 1 to 6 carbons, and n is an integer between, and including, 0
and 2, and; R.sub.2 is independently hydrogen, lower alkyl of 1 to
6 carbons, F, Cl, Br, I, CF.sub.3, fluoro substituted alkyl of 1 to
6 carbons, OH, SH, alkoxy of 1 to 6 carbons, or alkylthio of 1 to 6
carbons, and; R.sub.3 is independently hydrogen, lower alkyl of 1
to 6 carbons or F, and; m is an integer having the value of 0-3,
and; o is an integer having the value of 0-3, and; Z is
--C.ident.C--, --N.dbd.N--, --N.dbd.CR.sub.1--, --CR.sub.1 .dbd.N,
--(CR.sub.1 .dbd.CR.sub.1).sub.n'-- where n' is an integer having
the value 0-5, --CO--NR.sub.1--, --CS--NR.sub.1--, --NR.sub.1--CO,
--NR.sub.1--CS, --COO--, --OCO--; --CSO--; --OCS--; Y is a phenyl
or naphthyl group, or heteroaryl selected from a group consisting
of pyridyl, thienyl, furyl, pyridazinyl, pyrimidinyl, pyrazinyl,
thiazolyl, oxazolyl, imidazolyl and pyrrazolyl, said phenyl and
heteroaryl groups being optionally substituted with one or two
R.sub.2 groups, or when Z is --(CR.sub.1.dbd.CR.sub.1).sub.n'-- and
n' is 3, 4 or 5 then Y represents a direct valence bond between
said (CR.sub.2.dbd.CR.sub.2).sub.n' group and B; A is
(CH.sub.2).sub.q where q is 0-5, lower branched chain alkyl having
3-6 carbons, cycloalkyl having 3-6 carbons, alkenyl having 2-6
carbons and 1 or 2 double bonds, alkynyl having 2-6 carbons and 1
or 2 triple bonds; B is hydrogen, COOH or a pharmaceutically
acceptable salt thereof, COOR.sub.8, CONR.sub.9R.sub.10,
--CH.sub.2OH, CH.sub.2OR.sub.11, CH.sub.2OCOR.sub.11, CHO,
CH(OR.sub.12).sub.2, CHOR.sub.13O, --COR.sub.7,
CR.sub.7(OR.sub.12).sub.2, CR.sub.7OR.sub.13O, or tri-lower
alkylsilyl, where R.sub.7 is an alkyl, cycloalkyl or alkenyl group
containing 1 to 5 carbons, R.sub.8 is an alkyl group of 1 to 10
carbons or trimethylsilylalkyl where the alkyl group has 1 to 10
carbons, or a cycloalkyl group of 5 to 10 carbons, or R.sub.8 is
phenyl or lower alkylphenyl, R.sub.9 and R.sub.10 independently are
hydrogen, an alkyl group of 1 to 10 carbons, or a cycloalkyl group
of 5-10 carbons, or phenyl or lower alkylphenyl, R.sub.11 is lower
alkyl, phenyl or lower alkylphenyl, R.sub.12 is lower alkyl, and
R.sub.13 is divalent alkyl radical of 2-5 carbons, and R.sub.14 is
(R.sub.15).sub.r-phenyl, (R.sub.15).sub.r-naphthyl, or
(R.sub.15).sub.r-heteroaryl where the heteroaryl group has 1 to 3
heteroatoms selected from the group consisting of O, S and N, r is
an integer having the values of 0-5, and R.sub.15 is independently
H, F, Cl, Br, I, NO.sub.2, N(R.sub.8).sub.2, N(R.sub.8)COR.sub.8,
NR.sub.8CON(R.sub.8).sub.2, OH, OCOR.sub.8, OR.sub.8, CN, an alkyl
group having 1 to 10 carbons, fluoro substituted alkyl group having
1 to 10 carbons, an alkenyl group having 1 to 10 carbons and 1 to 3
double bonds, alkynyl group having 1 to 10 carbons and 1 to 3
triple bonds, or a trialkylsilyl or trialkylsilyloxy group where
the alkyl groups independently have 1 to 6 carbons.
26. The contraceptive of claim 24, wherein said RAR antagonist or
inverse agonist has the structure: 33wherein X is S, O, NR' where
R' is H or alkyl of 1 to 6 carbons, or X is
[C(R.sub.1).sub.2].sub.n where R.sub.1 is independently H or alkyl
of 1 to 6 carbons, and n is an integer between, and including, 0
and 2, and; R.sub.2 is independently hydrogen, lower alkyl of 1 to
6 carbons, F, Cl, Br, I, CF.sub.3, fluoro substituted alkyl of 1 to
6 carbons, OH, SH, alkoxy of 1 to 6 carbons, or alkylthio of 1 to 6
carbons, and; R.sub.3 is independently hydrogen, lower alkyl of 1
to 6 carbons or F, and; m is an integer having the value of 0, 1,
2, or 3, and; o is an integer having the value of 0, 1, 2, or 3,
and; Y is a phenyl or naphthyl group, or heteroaryl selected from a
group consisting of pyridyl, thienyl, furyl, pyridazinyl,
pyrimidinyl, pyrazinyl, thiazolyl, oxazolyl, imidazolyl and
pyrrazolyl, said phenyl and heteroaryl groups being optionally
substituted with one or two R.sub.2 groups, and; A is
(CH.sub.2).sub.q where q is 0-5, lower branched chain alkyl having
3-6 carbons, cycloalkyl having 3-6 carbons, alkenyl having 2-6
carbons and 1 or 2 double bonds, alkynyl having 2-6 carbons and 1
or 2 triple bonds, and; B is hydrogen, COOH or a pharmaceutically
acceptable salt thereof, COOR.sub.8, CONR.sub.9R.sub.10,
--CH.sub.2OH, CH.sub.2OR.sub.11, CH.sub.2OCOR.sub.11, CHO,
CH(OR.sub.12).sub.2, CHOR.sub.13O, --COR.sub.7,
CR.sub.7(OR.sub.12).sub.2, CR.sub.7OR.sub.13O, or tri-lower
alkylsilyl, where R.sub.7 is an alkyl, cycloalkyl or alkenyl group
containing 1 to 5 carbons, R.sub.8 is an alkyl group of 1 to 10
carbons or trimethylsilylalkyl where the alkyl group has 1 to 10
carbons, or a cycloalkyl group of 5 to 10 carbons, or R.sub.8 is
phenyl or lower alkylphenyl, R.sub.9 and R.sub.10 independently are
hydrogen, an alkyl group of 1 to 10 carbons, or a cycloalkyl group
of 5-10 carbons, or phenyl or lower alkylphenyl, R.sub.11 is lower
alkyl, phenyl or lower alkylphenyl, R.sub.12 is lower alkyl, and
R.sub.13 is divalent alkyl radical of 2-5 carbons, and; R.sub.14 is
(R.sub.15).sub.r-phenyl, (R.sub.15).sub.r-naphthyl, or
(R.sub.15).sub.r-heteroaryl where the heteroaryl group has 1 to 3
heteroatoms selected from the group consisting of O, S and N, r is
an integer having the values of 0, 1, 2, 3, 4 or 5, and; R.sub.15
is independently H, F, Cl, Br, I, NO.sub.2, N(R.sub.8).sub.2,
N(R.sub.8)COR.sub.8, NR.sub.8CON(R.sub.8).sub.2, OH, OCOR.sub.8,
OR.sub.8, CN, an alkyl group having 1 to 10 carbons, fluoro
substituted alkyl group having 1 to 10 carbons, an alkenyl group
having 1 to 10 carbons and 1 to 3 double bonds, alkynyl group
having 1 to 10 carbons and 1 to 3 triple bonds, or a trialkylsilyl
or trialkylsilyloxy group where the alkyl groups independently have
1 to 6 carbons, and; R.sub.16 is H, lower alkyl of 1 to 6 carbons,
and; R.sub.17 is H, lower alkyl of 1 to 6 carbons, OH or
OCOR.sub.1, and; p is zero or 1, with the proviso that when p is 1
then there is no R.sub.17 substituent group, and m is an integer
between, and including, 0 and 2.
27. The contraceptive of claim 24, wherein said RAR antagonist or
inverse agonist has the structure: 34where X is C(R.sub.1).sub.2 or
O, and; R.sub.1 is H or alkyl of 1 to 6 carbons, and; R.sub.2 is
independently lower alkyl of 1 to 6 carbons, F, Cl, Br, I,
CF.sub.3, fluoro substituted alkyl of 1 to 6 carbons, OH, SH,
alkoxy of 1 to 6 carbons, or alkylthio of 1 to 6 carbons, and; m is
an integer having the value of 0-3, and; R.sub.3 is independently
lower alkyl of 1 to 6 carbons or F, and; o is an integer having the
value of 0-3, and; s is an integer having the value of 1-3, and;
R.sub.8 is an alkyl group of 1 to 10 carbons or trimethylsilylalkyl
where the alkyl group has 1 to 10 carbons, or a cycloalkyl group of
5 to 10 carbons, or R.sub.8 is phenyl or lower alkylphenyl, and;
R.sub.15 is independently H, F, Cl, Br, I, NO.sub.2,
N(R.sub.8).sub.2, COR.sub.8, NR.sub.8CON(R.sub.8).sub.2,
OCOR.sub.8, OR.sub.8, CN, an alkyl group having 1 to 10 carbons,
fluoro substituted alkyl group having 1 to 10 carbons, an alkenyl
group having 1 to 10 carbons and 1 to 3 double bonds, an alkynyl
group having 1 to 10 carbons and 1 to 3 triple bonds, or a
trialkylsilyl or trialkylsilyloxy group where the alkyl groups
independently have 1 to 6 carbons, and; t is an integer having the
values of 0, 1, 2, 3, 4, or 5, and; the CONH group is in the 6 or 7
position of the benzopyran, and in the 2 or 3 position of the
dihydronaphthaline ring, or a pharmaceutically acceptable salt of
said compound.
28. The contraceptive of claim 24, wherein said RAR antagonist or
inverse agonist has the structure: 35where X is C(CH.sub.3).sub.2
or O, and; R.sub.2 is H or Br, and; R.sub.2' and R.sub.2"
independently are H or F, and; R.sub.3 is H or CH.sub.3, and;
R.sub.8 is H, lower alkyl of 1 to 6 carbons; and 36wherein X.sub.1
is: --C(R.sub.1).sub.2--, --C(R.sub.1).sub.2--C(R.sub.1).sub.2--,
--S--, --O--, --NR.sub.1--, --C(R.sub.1).sub.2--O--,
--C(R.sub.1).sub.2--S--, or C(R.sub.1)--NR.sub.1--; and R.sub.1 is
independently H or alkyl of 1 to 6 carbons; and R.sub.2 is optional
and is independently defined as lower alkyl of 1 to 6 carbons, F,
Cl, Br, I, CF.sub.3, fluoro substituted alkyl of 1 to 6 carbons, OH
SH, alkoxy of 1 to 6 carbons, or alkylthio of 1 to 6 carbons; and m
is an integer between, and including, 0 and 4; and n is an integer
between, and including, 0 and 2; and o is an integer between, and
including, 0 and 3; and R.sub.3 is H, lower alkyl of 1 to 6
carbons, F, Cl, Br or I; and R.sub.4 is (R.sub.5).sub.p-phenyl,
(R.sub.5).sub.p-naphthyl, (R.sub.5).sub.p-heteroaryl where the
heteroaryl group is five-membered or 6-membered and has 1 to 3
heteroatoms selected from the group consisting of O, S, and N; and
p is an integer between, and including, 0 and 5; and R.sub.5 is
optional and is defined as independently F, Cl, Br, I, NO.sub.2,
N(R.sub.8).sub.2, N(R.sub.8)COR.sub.8,
N(R.sub.8)CON(R.sub.8).sub.2, OH, OCOR.sub.8, OR.sub.8, CN, COOH,
COOR.sub.8, an alkyl group having from 1 to 10 carbons, an alkenyl
group having from 1 to 10 carbons and 1 to three double bonds,
alkynyl group having from 1 to 10 carbons and 1 to 3 triple bonds,
or a (trialkyl)silyl or (trialkyl)silyloxy group where the alkyl
groups independently have from 1 to 6 carbons; and Y is a phenyl or
naphthyl group, or a heteroaryl selected from the group consisting
of pyridyl, thienyl, furyl, pyridazinyl, pyrimidinyl, pyrazinyl,
thiazolyl, oxazolyl, imidazolyl and pyrrazolyl, said phenyl and
heteroaryl groups being optionally substituted with one or two
R.sub.2 groups, or Y is --(CR.sub.3.dbd.CR.sub.3).sub.r; and r is
an integer between, and including, 1 and 3; and A is
(CH.sub.2).sub.q where q is an integer from 0-5, lower branched
chain alkyl having from 3 to 6 carbons, cycloalkyl having from 3 to
6 carbons, alkenyl having from 2 to 6 carbons and 1 or 2 double
bonds, alkenyl having from 2 to 6 carbons and 1 or 2 triple bonds,
with the proviso that when Y is --(CR.sub.3.dbd.CR.sub.3).sub.r--
then A is (CH.sub.2).sub.q and q is 0; and B is H, COOH or a
pharmaceutically acceptable salt thereof, COOR.sub.8,
CONR.sub.9R.sub.10,--CH.sub.2OH, CH.sub.2OR.sub.11,
CH.sub.2OCOR.sub.11, CHO, CH(OR.sub.12).sub.2, CHOR.sub.13O,
--COR.sub.7, CR.sub.7(OR.sub.12).sub.2, CR.sub.7OR.sub.13O, or
Si(C.sub.1-6alkyl).sub.3, wherein R.sub.7 is an alkyl, cycloalkyl
or alkenyl group containing 1 to 5 carbons, R.sub.8 is an alkyl
group of 1 to 10 carbons or (trimethylsilyl)alkyl, where the alkyl
groups has 1 to 10 carbons, or a cycloalkyl group of 5 to 10
carbons, or R.sub.8 is phenyl or lower alkylphenyl, R.sub.8 and
R.sub.10 independently are H, a lower alkyl group of 1 to 10
carbons, or a cycloalkyl group of 5-10 carbons, or phenyl or lower
alkylphenyl, R.sub.11 is lower alkyl, phenyl or lower alkylphenyl,
R.sub.12 is lower alkyl, and R.sub.13 is a divalent alkyl radical
of 2-5 carbons;
29. The contraceptive of claim 24, wherein said RAR antagonist or
inverse agonist has the structure: 37where X.sub.1 is S or O;
X.sub.2 is CH or N; R.sub.2 is H, F, CF.sub.3 or alkoxy of 1 to 6
carbons; R.sub.2* is H, F, or CF.sub.3; R.sub.8 is H, or lower
alkyl of 1 to 6 carbons; R.sub.14 is unsubstituted phenyl, thienyl
or pyridyl, or phenyl, thienyl or pyridyl substituted with one to
three R.sub.15 groups, where R.sub.15 is lower alkyl of 1 to 6
carbons, chlorine, CF.sub.3, or alkoxy of 1 to 6 carbons, or a
pharmaceutically acceptable salt of said compound; and 38wherein
X.sub.2 is CH or N, and; R.sub.2 is H, F, or OCH.sub.3, and;
R.sub.2* is H or F, and; R.sub.8 is H, or lower alkyl of 1 to 6
carbons, and; R.sub.14 is selected from the group consisting of
phenyl, 4-(lower-alkyl)phenyl, 5-(lower alkyl)-2-thienyl, and
6-(lower alkyl)-3-pyridyl where lower alkyl has 1 to 6 carbons; and
39where R.sub.2* is H or F; R.sub.8 is H, or lower alkyl of 1 to 6
carbons, and R.sub.14 is selected from the group consisting of
phenyl, and 4-(lower-alkyl)phenyl, where lower alkyl has 1 to 6
carbons, and pharmaceutically acceptable salts thereof.
30. The contraceptive of claim 24, wherein said RAR antagonist or
inverse agonist has the structure: 40where R.sub.8 is H, lower
alkyl of 1 to 6 carbons, or a pharmaceutically acceptable salt of
said compound.
31. The contraceptive of claim 24, wherein said RAR antagonist or
inverse agonist has the structure: 41where R.sub.8 is H, lower
alkyl of 1 to 6 carbons, or a pharmaceutically acceptable salt of
said compound.
32. The contraceptive of claim 24, wherein said RAR antagonist or
inverse agonist has the structure:
Y.sub.3(R.sub.4)--X--Y.sub.1(R.sub.1R.sub.2)-Z-
-Y.sub.2(R.sub.2)-A-B Where Y.sub.1 is phenyl, naphthyl, or
heteroaryl selected from the group consisting of pyridyl, thienyl,
furyl, pyridazinyl, pyrimidinyl, pyrazinyl, thiazonyl, ozazolyl,
imidazolyl, and pyrrazolyl, said phenyl, naphthyl, and heteroaryl
groups being substituted with an R.sub.1 group, and further
substituted or unsubstituted with one or two R.sub.2 groups;
R.sub.1 is C.sub.1-10 alkyl, 1-ademantyl, 2-tetrahydropyranoxy,
trialkylsilanyloxy where alkyl has up to 6 carbons, OH, alkoxy
where the alkyl group has up to 10 carbons, alkylthio where the
alkyl group has up to 10 carbons, or OCH.sub.2OC.sub.1-6 alkyl;
R.sub.2 is lower alkyl of 1 to 6 carbons, F, Cl, Br, I, CF.sub.3,
CF.sub.2CF.sub.3, OH, OR.sub.3, NO.sub.2, N(R.sub.3).sub.2, CN,
N.sub.3, COR.sub.3, NHCOR.sub.3, COOH, or COOR.sub.3; X is
(C(R.sub.3).sub.2, S, SO, SO.sub.2, O or NR.sub.3; Z is
--C.ident.C--, --N.dbd.N--, --N(O).dbd.N--, --N.dbd.N(O)--,
--N.dbd.CR.sub.3--, --CR.sub.3.dbd.N,
--(CR.sub.3.dbd.CR.sub.3).sub.n-- where n is an integer having the
value 0-5, --CO--NR.sub.3--, --CS--NR.sub.3--, --NR.sub.3--CO,
--NR.sub.3--CS, --COO--, --OCO--; --CSO--; --OCS--; or
--CO--CR.sub.3.dbd.R.sub.3--O. R.sub.3 is independently H or lower
alkyl of 1 to 6 carbons; Y.sub.2 is a phenyl or naphthyl group, or
heteroaryl selected from a group consisting of pyridyl, thienyl,
furyl, pyridazinyl, pyrimidinyl, pyrazinyl, thiazolyl, oxazolyl,
imidazolyl and pyrrazolyl, said phenyl, naphthyl and heteroaryl
groups being unsubstituted or substituted with one or two R.sub.2
groups, or when Z is --(CR.sub.3.dbd.CR.sub.3).sub.n-- and n is 3,
4 or 5 then Y.sub.2 represents a direct valence bond between said
--(CR.sub.3.dbd.CR.sub.3).sub.n group and B; Y.sub.3 is phenyl,
naphthyl, or heteroaryl selected from a group consisting of
pyridyl, thienyl, furyl, pyridazinyl, pyrimidinyl, pyrazinyl,
thiazolyl, oxazolyl, imidazolyl and pyrrazolyl, said phenyl,
naphthyl and heteroaryl groups being unsubstituted or substituted
with one to three R.sub.4 groups, where R.sub.4 is alkyl of 1 to 10
carbons, fluoro-substituted alkyl of 1 to 10 carbons, alkenyl of 2
to 10 carbons and having 1 to 3 triple bonds, F, Cl, Br, I,
NO.sub.2, CN, NR.sub.3, N.sub.3, COOH, COOC.sub.1-6 alkyl, OH, SH,
OC.sub.1-6 alkyl, and SC.sub.1-6 alkyl; A is (CH.sub.2).sub.q where
q is from 0-5, lower branched alkyl having 3-6 carbons, cycloalkyl
having 3-6 carbons, alkenyl, having 2-6 carbons and 1-2 double
bonds, alkynyl having 2-6 carbons and 1 to 2 triple bonds, and B is
hydrogen, COOH or a pharmaceutically acceptable salt thereof,
COOR.sub.8, CONR.sub.9R.sub.10, --CH.sub.2OH, CH.sub.2OR.sub.11,
CH.sub.2OCOR.sub.11, CHO, CH(OR.sub.12).sub.2, CHOR.sub.13O,
--COR.sub.7, CR.sub.7(OR.sub.12).sub.2, CR.sub.7OR.sub.13O, or
Si(C.sub.1-6 alkyl).sub.3, where R.sub.7 is an alkyl, cycloalkyl or
alkenyl group containing 1 to 5 carbons, R.sub.8 is an alkyl group
of 1 to 10 carbons or trimethylsilylalkyl where the alkyl group has
1 to 10 carbons, or a cycloalkyl group of 5 to 10 carbons, or
R.sub.8 is phenyl or lower alkylphenyl, R.sub.9 and R.sub.10
independently are hydrogen, an alkyl group of 1 to 10 carbons, or a
cycloalkyl group of 5-10 carbons, or phenyl or lower alkylphenyl,
R.sub.11 is lower alkyl, phenyl or lower alkylphenyl, R.sub.12 is
lower alkyl, and R.sub.13 is divalent alkyl radical of 2-5 carbons,
and pharmaceutically acceptable salts thereof.
33. The contraceptive of claim 24, wherein said RAR antagonist or
inverse agonist has the structure: 42where n is an integer from 1
to 10, and pharmaceutically accept6able salts thereof.
34. The contraceptive of claim 24, wherein said RAR antagonist or
inverse agonist has the structure: 43where n is an integer from 1
to 10, and pharmaceutically acceptable salts thereof.
35. The contraceptive of claim 24, wherein said RAR antagonist or
inverse agonist has the structure: 44
36. The contraceptive of claim 24, wherein said RAR antagonist or
inverse agonist has the structure: 45
37. The contraceptive of claim 24, wherein said RAR antagonist or
inverse agonist has the structure: 46
38. The contraceptive of claim 24 wherein said excipient is
optimized for epidermal delivery.
39. The contraceptive of claim 24 wherein said RAR antagonist or
inverse agonist is dissolved in a triglyceride preparation.
40. The contraceptive of claim 38 wherein said excipient comprises
an emulsion comprising benzyl alcohol, medium chain triglycerides,
Carbomer 1342, sorbitan monooleate, Carbomer 934P, and EDTA.
41. The contraceptive of claim 24 wherein said excipient is
optimized for systemic delivery.
42. The contraceptive of claim 24 wherein said excipient is
optimized for oral delivery.
Description
[0001] This application is a continuation in part of application
Ser. No. 09/405,748, filed Sep. 27, 1999, which claimed priority
under 35 USC 119(e) to provisional application Serial No.
60/103,507, filed Oct. 8, 1998. Both of these applications are
incorporated by reference herein.
FIELD OF THE INVENTION
[0002] The present invention concerns methods and compositions for
inhibiting or blocking fertility in a male mammal by the
administration of a retinoid or retinoid derivative that is able to
act as an antagonist or inverse agonist of a retinoic acid receptor
(RAR). The effect is reversible upon cessation of treatment with
the RAR antagonist or inverse agonist.
BACKGROUND OF THE INVENTION
[0003] The prevention of unplanned pregnancy in humans and other
mammals is of continuing concern for both the developing and the
developed world. A variety of methods and products have been
proposed or developed for the prevention of pregnancy; these
products include: surgical sterilization, condoms, birth control
pills containing progestin or a combination of progestin and
estrogen, subdermal implants containing delayed release forms of
progesterone, intrauterine devices, spermicidal creams or gels, and
intravaginal barriers such as sponges or diaphragms.
[0004] These various methods each have certain advantages and
certain drawbacks. The most common non-surgical birth control
method in the United States is the birth control pill ("the Pill"),
which contains synthetic progestin and estrogen; synthetic hormones
similar to those produced naturally in a woman's body. The Pill
works primarily by suppressing the release of eggs from a woman's
ovaries.
[0005] Within two years after its introduction in 1960,
approximately 1.2 million women were using oral birth control, and
by 1973, about 10 million women were using the Pill. However, in
recent years questions have arisen about the health risks involved
in continued long term use of contraceptive hormones. There have
been reports of increased risk of certain forms of cancer, such as
breast and cervical cancer, though the use of the Pill.
[0006] Surgical sterilization, whether through tubal ligation or
vasectomy, is nearly 100% effective, but is only sometimes
reversible. Reversal of surgical sterilization usually requires
further surgery.
[0007] Condoms, made of either synthetic polymer materials or
animal skin, are less effective than birth control pills and their
effectiveness is further subject to subversion through the
possibility that small breaks may be present, permitting leakage of
semen. Additionally, the use of a condom requires the affirmative
action of the male, usually immediately prior to the initiation of
sexual intercourse and some men report a loss of sensation through
the use of condoms. Hence, subject non-compliance is also an issue
in the use of condoms.
[0008] Subdermal implants, such as the NORPLANT.RTM. implant
device, are quite effective contraceptive means. The implant
comprises a set of silicone rods that are inserted under the skin
of the upper arm. The implant contains hormones, such as progestin,
levonorgestrel and progesterone, that are slowly released over a
period of time of up to five years. Side effects may be similar to
those involved in the use of birth control pills, and include a
risk of developing ovarian cysts. Additionally, while the implant
can be removed, the procedure is difficult even for skilled
surgeons due to the formation of scar tissue around the
implant.
[0009] Intrauterine devices (IUDs) are small devices that are
typically either made of copper or impregnated with progesterone.
These must be inserted (and removed) by a doctor. Depending on the
design, the devices appear to interfere with sperm motility or the
implantation of the fertilized egg in the uterine wall. Side
effects can include cramps, backache, spotting, or heavy periods,
and women may have an increased risk of ectopic pregnancy or
infertility. IUDs are usually not recommended for women who have
not had children or who think they will have children in the future
due to these latter risks. Normally, the contraceptive effects are
reversible upon removal of the device.
[0010] Barriers such as diaphragms and sponges are usually used in
conjunction with a spermicidal cream, foam, or gel. The
effectiveness of such devices is between about 90% and about 95%.
The user can insert them as long as a number of hours before sexual
intercourse, and the effects are temporary; if pregnancy is
subsequently desired, the woman can discontinue their use with a
concomitant return of fertility.
[0011] With the exception of surgical sterilization and the use of
condoms, all of the methods in common use affect female fertility
with no effect on male fertility. As mentioned above, the former of
these methods is irreversible and the latter is neither inherently
as effective as other methods, nor is compliance as high. A male
contraceptive that is not required to be applied immediately prior
to intercourse would provide a contraceptive alternative to the
traditional methods of contraception.
[0012] A number of compositions have been proposed for use as a
male contraceptive. Thus, U.S. Pat. No. 5,501,855, to Talwar et
al., describes application of neem (Azadirachta indica) oil by
injection to the vas deferens in an amount effective to block the
fertility of the male by spermatogenic arrest. A single injection
was reported to be effective to block fertility over the 9 month
period of observation reported in the '855 patent.
[0013] U.S. Pat. No. 4,677,193 and International Patent Publication
No. WO 94/19370, both to Rivier et al., describe a hypothalamic
peptide hormone (termed GnRH) that functions to trigger the release
of gonadotropic hormones such a luteinizing hormone (LH) and
follicle-stimulating hormone (FSH) in the female. These references
also mention that antagonists of GnRH are effective to arrest
spermatogenesis in male mammals. This treatment apparently requires
supplemental testosterone to be provided with the treatment in
order to maintain libido.
[0014] U.S. Pat. No. 5,744,448, to Kelton et al., describes the
cloning, expression, and purification of human FSH receptor, or
mutants or fragments thereof that retain the ability to bind FSH.
One possible use of the FSH receptor is described as a method for
preventing spermatogenesis in a male patient.
[0015] U.S. Pat. Nos. 4,182,891, to Metcalf et al., and 4,134,918,
to Bey et al. describe compounds said to be useful in inhibiting
spermatogenesis. The '891 patent describes acetylenic derivatives
of amino acids, and the '918 patent describes halomethyl
derivatives of amines.
[0016] International Patent Publication No. WO 97/24901, to Bandman
et al., describes the amino acid sequence of a polypeptide termed
Lung Growth Factor Variant (LGFV), which is said to play a role in
various physiological processes, including spermatogenesis.
[0017] U.S. Pat. No. 5,753,231, to Herr, et al., describes a female
contraceptive vaccine prepared from antibodies raised to a
recombinant primate acrosomal sperm antigen. The vaccine elicits an
anti-sperm immune response, resulting in inhibition of
fertilization. Also described are contraceptive compositions
containing such an antibody in a carrier for vaginal
application.
[0018] None of the references cited herein are admitted in any
manner to be prior art against the present application.
SUMMARY OF THE INVENTION
[0019] The present invention concerns the discovery that certain
agents that are able to block the binding of retinoic acid (RA) or
other RAR ligands to RAR receptors, and thereby prevent activation
of RARs, are also able to inhibit spermatogenesis in a male
mammal.
[0020] It has been known for some time that among the various
results of a severe vitamin A (retinol) deficiency in mammals is
sterility and blindness. See Eskild, W. & Hansson, V., Vitamin
A Functions in the Reproductive Organs in Vitamin A in Health and
Disease 531 (Blomhoff, R. ed., 1994) (hereinafter Eskild). A
complete deficiency in retinoids is fatal. Administration of
retinoic acid in the absence of retinol can alleviate many of the
symptoms of vitamin A deficiency, giving rise to blind and sterile
animals that remain otherwise healthy.
[0021] Researchers have also noted that treatment of vitamin
A-deficient rats (in which there was a complete spermatogenic
arrest) with vitamin A replacement results in restoration of normal
spermatogenesis; reinitiation of spermatogenesis occurs in rats
within 24-48 hours following vitamin A replacement. Huang, et al.,
112 Endocrinology 1163-71 (1983), incorporated by reference
herein.
[0022] A vast array of specific metabolic, developmental, and
catabolic processes appear to be directly or indirectly regulated
in vivo by comparatively small molecules such as steroids,
retinoids and thyroid hormones. The mechanism whereby a single such
compound can contribute to the regulation of numerous different
cellular events was the subject of much speculation until
relatively recently, when it was discovered that these compounds
each share the ability to bind to transcriptionally active
proteinaceous receptors. These protein receptors, in turn, are able
to bind specific cis-acting nucleic acid regulatory sequence
regions, termed response elements or RE's, located upstream of the
coding sequence of certain genes and to activate the transcription
of these genes. Thus, these proteinaceous receptors can serve as
specific, ligand-dependent regulators of gene transcription and
expression.
[0023] The amino acid sequences of these various receptors were
quickly found to share regions of homology, thus making each such
receptor a member of a family of ligand-modulated receptor
molecules. This family has been termed the steroid superfamily of
nuclear hormone receptors; nuclear, because the receptors are
usually found in high concentration in the nucleus of the cell,
although it is not clear that these are always the only relevant
locations in which these receptors are found, or that
transcriptional activation is the only activity that the receptors
possess.
[0024] Further study of the structural and functional relationship
between the nuclear hormone receptors has shown certain
characteristics in common between them in addition to sequence
homology. See e.g., Evans et al. Science 240:889-895 (1988). As
stated above, the nuclear hormone receptors are able to bind to
cis-acting regulatory elements present in the promoters of the
target genes. The glucocorticoid, estrogen, androgen, progestin,
and mineralcorticoid receptors have been found to bind as
homodimers to specific response elements organized as inverted
repeats.
[0025] Another class of nuclear hormone receptors, which includes
the retinoid receptor RAR (retinoic acid receptor), the thyroid
receptor, the vitamin D receptor, the peroxisome proliferator
receptor, and the insect ecdysone receptor bind their response
element as a heterodimer in conjunction with the retinoid X
receptor (RXR), which in turn is positively activated by 9-cis
retinoic acid. See Mangelsdorf, et al., The Retinoid Receptors in
The Retinoids: Biology, Chemistry and Medicine Ch.8 (Sporn et al.,
eds. 2d ed., Raven Press Ltd. 1994); Nagpal and Chandraratna,
Current Pharm. Design 2:295-316 (1996), which are both incorporated
by reference herein. The retinoid receptors RAR and RXR, like many
nuclear receptors, exist as a number of subtypes (RAR.alpha.,
RAR.beta., RAR.gamma., and RXR.alpha., RXR.beta., and RXR.gamma.).
Additionally, each subtype may exist in different isoforms.
[0026] The present Applicants have surprisingly discovered that
administration of an RAR antagonist or RAR inverse agonist results
in the arrest of spermatogenesis in male mammals. By "antagonist"
is meant that an agent is able to bind to the retinoic acid binding
site of an RAR, thereby blocking the binding of retinoic acid to,
and activation of the RAR. By "inverse agonist" is meant an agent
able to suppress the basal level of RAR activity (homo- or
heterodimerization and trans-acting transcriptional control of
various genes whose regulation is normally responsive to RAR
modulation). A compound will normally be an RAR antagonist if it is
an inverse agonist, but the converse is not necessarily true.
[0027] The spermatogenetic arrest resulting from treatment of a
male mammal with an effective amount of an RAR antagonist or
inverse agonist is not accompanied by most other symptoms of
hypovitaminosis A, such as blindness, abnormal growth or
susceptibility to infectious disease. Testosterone levels appear to
remain normal; thus the preferred agents do not significantly
affect male libido and sexuality.
[0028] This, these compositions have applicability as agents for
veterinary or therapeutic application as a male contraceptive.
[0029] Some examples of structures and methods of making and using
preferred RAR antagonists and inverse agonists are provided in U.S.
Pat. No. 5,776,699 and U.S. patent application Ser. No. 08/998,319,
08/880,823, and 08/840,040 which are all incorporated by reference
herein in their entirety. Many of the following compounds are
included in one or more of these applications.
[0030] A class of preferred compounds has the structure: 1
[0031] wherein
[0032] X is S, O, NR' where R' is H or alkyl of 1 to 6 carbons,
or
[0033] X is [C(R.sub.1).sub.2].sub.n where R.sub.1 is independently
H or alkyl of 1 to 6 carbons, and n is an integer between, and
including, 0 and 2, and;
[0034] R.sub.2 is hydrogen, lower alkyl of 1 to 6 carbons, F, Cl,
Br, I, CF.sub.3, fluoro substituted alkyl of 1 to 6 carbons, OH,
SH, alkoxy of 1 to 6 carbons, or alkylthio of 1 to 6 carbons,
and;
[0035] R.sub.3 is hydrogen, lower alkyl of 1 to 6 carbons or F,
and;
[0036] m is an integer having the value of 0-3, and;
[0037] o is an integer having the value of 0-3, and;
[0038] Z is --C.ident.C--,
[0039] --N.dbd.N--,
[0040] --N.dbd.CR.sub.1--,
[0041] --CR.sub.1.dbd.N,
[0042] --(CR.sub.1 .dbd.CR.sub.1).sub.n'-- where n' is an integer
having the value 0-5,
[0043] --CO--NR.sub.1--,
[0044] --CS--NR.sub.1--,
[0045] --NR.sub.1--CO,
[0046] --NR.sub.1--CS,
[0047] --COO--,
[0048] --OCO--;
[0049] --CSO--;
[0050] --OCS--;
[0051] Y is a phenyl or naphthyl group, or heteroaryl selected from
a group consisting of pyridyl, thienyl, furyl, pyridazinyl,
pyrimidinyl, pyrazinyl, thiazolyl, oxazolyl, imidazolyl and
pyrrazolyl, said phenyl and heteroaryl groups being optionally
substituted with one or two R.sub.2 groups, or
[0052] when Z is --(CR.sub.1.dbd.CR.sub.1).sub.n'-- and n' is 3, 4
or 5 then Y represents a direct valence bond between said
(CR.sub.2.dbd.CR.sub.2).sub.n group and B;
[0053] A is (CH.sub.2).sub.q where q is 0-5, lower branched chain
alkyl having 3-6 carbons, cycloalkyl having 3-6 carbons, alkenyl
having 2-6 carbons and 1 or 2 double bonds, alkynyl having 2-6
carbons and 1 or 2 triple bonds;
[0054] B is hydrogen, COOH or a pharmaceutically acceptable salt
thereof, COOR.sub.8, CONR.sub.9R.sub.10, --CH.sub.2OH,
CH.sub.2OR.sub.11, CH.sub.2OCOR.sub.11, CHO, CH(OR.sub.12).sub.2,
CHOR.sub.13O, --COR.sub.7, CR.sub.7(OR.sub.12).sub.2,
CR.sub.7OR.sub.13O, or tri-lower alkylsilyl, where R.sub.7 is an
alkyl, cycloalkyl or alkenyl group containing 1 to 5 carbons,
R.sub.8 is an alkyl group of 1 to 10 carbons or trimethylsilylalkyl
where the alkyl group has 1 to 10 carbons, or a cycloalkyl group of
5 to 10 carbons, or R.sub.8 is phenyl or lower alkylphenyl, R.sub.9
and R.sub.10 independently are hydrogen, an alkyl group of 1 to 10
carbons, or a cycloalkyl group of 5-10 carbons, or phenyl or lower
alkylphenyl, R.sub.11 is lower alkyl, phenyl or lower alkylphenyl,
R.sub.12 is lower alkyl, and R.sub.13 is divalent alkyl radical of
2-5 carbons, and
[0055] R.sub.14 is (R.sub.15).sub.r-phenyl,
(R.sub.15).sub.r-naphthyl, or (R.sub.15).sub.r-heteroaryl where the
heteroaryl group has 1 to 3 heteroatoms selected from the group
consisting of O, S and N, r is an integer having the values of 0-5,
and
[0056] R.sub.15 is independently H, F, Cl, Br, I, NO.sub.2,
N(R.sub.8).sub.2, N(R.sub.8)COR.sub.8, NR.sub.8CON(R.sub.8).sub.2,
OH, OCOR.sub.8, OR.sub.8, CN, an alkyl group having 1 to 10
carbons, fluoro substituted alkyl group having 1 to 10 carbons, an
alkenyl group having 1 to 10 carbons and 1 to 3 double bonds,
alkynyl group having 1 to 10 carbons and 1 to 3 triple bonds, or a
trialkylsilyl or trialkylsilyloxy group where the alkyl groups
independently have 1 to 6 carbons.
[0057] Another preferred class of compounds has the structure:
2
[0058] wherein
[0059] X is S, O, NR' where R' is H or alkyl of 1 to 6 carbons,
or
[0060] X is [C(R.sub.1).sub.2].sub.n where R.sub.1 is independently
H or alkyl of 1 to 6 carbons, and n is an integer between, and
including, 0 and 2, and;
[0061] R.sub.2 is hydrogen, lower alkyl of 1 to 6 carbons, F, Cl,
Br, I, CF.sub.3, fluoro substituted alkyl of 1 to 6 carbons, OH,
SH, alkoxy of 1 to 6 carbons, or alkylthio of 1 to 6 carbons,
and;
[0062] R.sub.3 is hydrogen, lower alkyl of 1 to 6 carbons or F,
and;
[0063] m is an integer having the value of 0, 1, 2, or 3, and;
[0064] o is an integer having the value of 0, 1, 2, or 3, and;
[0065] Y is a phenyl or naphthyl group, or heteroaryl selected from
a group consisting of pyridyl, thienyl, furyl, pyridazinyl,
pyrimidinyl, pyrazinyl, thiazolyl, oxazolyl, imidazolyl and
pyrrazolyl, said phenyl and heteroaryl groups being optionally
substituted with one or two R.sub.2 groups, and;
[0066] A is (CH.sub.2).sub.q where q is 0-5, lower branched chain
alkyl having 3-6 carbons, cycloalkyl having 3-6 carbons, alkenyl
having 2-6 carbons and 1 or 2 double bonds, alkynyl having 2-6
carbons and 1 or 2 triple bonds, and;
[0067] B is hydrogen, COOH or a pharmaceutically acceptable salt
thereof, COOR.sub.8, CONR.sub.9R.sub.10, --CH.sub.2OH,
CH.sub.2OR.sub.11, CH.sub.2OCOR.sub.11, CHO, CH(OR.sub.12).sub.2,
CHOR.sub.13O, --COR.sub.7, CR.sub.7(OR.sub.12).sub.2,
CR.sub.7OR.sub.13O, or tri-lower alkylsilyl, where R.sub.7 is an
alkyl, cycloalkyl or alkenyl group containing 1 to 5 carbons,
R.sub.8 is an alkyl group of 1 to 10 carbons or trimethylsilylalkyl
where the alkyl group has 1 to 10 carbons, or a cycloalkyl group of
5 to 10 carbons, or R.sub.8 is phenyl or lower alkylphenyl, R.sub.9
and R.sub.10 independently are hydrogen, an alkyl group of 1 to 10
carbons, or a cycloalkyl group of 5-10 carbons, or phenyl or lower
alkylphenyl, R.sub.11 is lower alkyl, phenyl or lower alkylphenyl,
R.sub.12 is lower alkyl, and R.sub.13 is divalent alkyl radical of
2-5 carbons, and;
[0068] R.sub.14 is (R.sub.15).sub.r-phenyl,
(R.sub.15).sub.r-naphthyl, or (R.sub.15).sub.r-heteroaryl where the
heteroaryl group has 1 to 3 heteroatoms selected from the group
consisting of O, S and N, r is an integer having the values of 0,
1, 2, 3, 4 or 5, and;
[0069] R.sub.15 is independently H, F, Cl, Br, I, NO.sub.2,
N(R.sub.8).sub.2, N(R.sub.8)COR.sub.8, NR.sub.8CON(R.sub.8).sub.2,
OH, OCOR.sub.8, OR.sub.8, CN, an alkyl group having 1 to 10
carbons, fluoro substituted alkyl group having 1 to 10 carbons, an
alkenyl group having 1 to 10 carbons and 1 to 3 double bonds,
alkynyl group having 1 to 10 carbons and 1 to 3 triple bonds, or a
trialkylsilyl or trialkylsilyloxy group where the alkyl groups
independently have 1 to 6 carbons, and;
[0070] R.sub.16 is H, lower alkyl of 1 to 6 carbons, and;
[0071] R.sub.17 is H, lower alkyl of 1 to 6 carbons, OH or
OCOR.sub.11, and;
[0072] p is 0 or 1, with the proviso that when p is 1 then there is
no R17 substituent group, and m is an integer between, and
including, 0 and 2.
[0073] A further preferred class of compounds is the class of the
structure: 3
[0074] where
[0075] X is C(R.sub.1).sub.2 or O, and;
[0076] R.sub.1 is H or alkyl of 1 to 6 carbons, and;
[0077] R.sub.2 is lower alkyl of 1 to 6 carbons, F, Cl, Br, I,
CF.sub.3, fluoro substituted alkyl of 1 to 6 carbons, OH, SH,
alkoxy of 1 to 6 carbons, or alkylthio of 1 to 6 carbons, and;
[0078] m is an integer having the value of 0-3, and;
[0079] R.sub.3 is lower alkyl of 1 to 6 carbons of F, and;
[0080] o is an integer having the value of 0-3, and;
[0081] s is an integer having the value of 1-3, and;
[0082] R.sub.8 is an alkyl group of 1 to 10 carbons or
trimethylsilylalkyl where the alkyl group has 1 to 10 carbons, or a
cycloalkyl group of 5 to 10 carbons, or R.sub.8 is phenyl or lower
alkylphenyl, and;
[0083] R.sub.15 is independently H, F, Cl, Br, I, NO.sub.2,
N(R.sub.8).sub.2, COR.sub.8, NR.sub.8CON(R.sub.8).sub.2,
OCOR.sub.8, OR.sub.8, CN, an alkyl group having 1 to 10 carbons,
fluoro substituted alkyl group having 1 to 10 carbons, an alkenyl
group having 1 to 10 carbons and 1 to 3 double bonds, an alkynyl
group having 1 to 10 carbons and 1 to 3 triple bonds, or a
trialkylsilyl or trialkylsilyloxy group where the alkyl groups
independently have 1 to 6 carbons, and;
[0084] t is an integer having the values of 0, 1, 2, 3, 4, or 5,
and; the CONH group is in the 6 or 7 position of the benzopyran,
and in the 2 or 3 position of the dihydronaphthaline ring, or a
pharmaceutically acceptable salt of said compound.
[0085] Another preferred class of compounds is that of the
structure: 4
[0086] where
[0087] X is C(CH.sub.3).sub.2 or O, and;
[0088] R.sub.2 is H or Br, and;
[0089] R.sub.2' and R.sub.2" independently are H or F, and;
[0090] R.sub.3 is H or CH.sub.3, and;
[0091] R.sub.8 is H, lower alkyl of 1 to 6 carbons, or a
pharmaceutically acceptable salt of said compound.
[0092] A further preferred class of such compounds has the
structure: 5
[0093] where
[0094] X.sub.1 is S or O;
[0095] X.sub.2 is CH or N;
[0096] R.sub.2 is H, F, CF.sub.3 or alkoxy of 1 to 6 carbons;
[0097] R.sub.2* H, F, or CF.sub.3;
[0098] R.sub.8 is H, or lower alkyl of 1 to 6 carbons;
[0099] R.sub.14 is unsubstituted phenyl, thienyl or pyridyl, or
phenyl, thienyl or pyridyl substituted with one to three R.sub.15
groups, where R.sub.15 is lower alkyl of 1 to 6 carbons, chlorine,
CF.sub.3, or alkoxy of 1 to 6 carbons, or a pharmaceutically
acceptable salt of said compound.
[0100] In yet another preferred embodiment of the invention, the
compound has the structure: 6
[0101] wherein
[0102] X.sub.2 is CH or N, and;
[0103] R.sub.2 is H, F, or OCH.sub.3, and;
[0104] R.sub.2* H or F, and;
[0105] R.sub.8 is H, or lower alkyl of 1 to 6 carbons, and;
[0106] R.sub.14 is selected from the group consisting of phenyl,
4-(lower-alkyl)phenyl, 5-(lower alkyl)-2-thienyl, and 6-(lower
alkyl)-3-pyridyl where lower alkyl has 1 to 6 carbons, or a
pharmaceutically acceptable salt of said compound.
[0107] A further preferred class of such compounds has the
structure: 7
[0108] where
[0109] X.sub.1 is S or O;
[0110] X.sub.2 is CH or N;
[0111] R.sub.2 is H, F, CF.sub.3 or alkoxy of 1 to 6 carbons;
[0112] R.sub.2* H, F, or CF.sub.3;
[0113] R.sub.8 is H, or lower alkyl of 1 to 6 carbons;
[0114] R.sub.14 is unsubstituted phenyl, thienyl or pyridyl, or
phenyl, thienyl or pyridyl substituted with one to three R.sub.15
groups, where R.sub.15 is lower alkyl of 1 to 6 carbons, chlorine,
CF.sub.3, or alkoxy of 1 to 6 carbons, or a pharmaceutically
acceptable salt of said compound.
[0115] In an even more preferred embodiment of the invention, the
compound has the structure: 8
[0116] wherein
[0117] X.sub.2 is CH or N, and;
[0118] R.sub.2 is H, F, or OCH.sub.3, and;
[0119] R.sub.2* H or F, and;
[0120] R.sub.8 is H, or lower alkyl of 1 to 6 carbons, and;
[0121] R.sub.14 is selected from the group consisting of phenyl,
4-(lower-alkyl)phenyl, 5-(lower alkyl)-2-thienyl, and 6-(lower
alkyl)-3-pyridyl where lower alkyl has 1 to 6 carbons, or a
pharmaceutically acceptable salt of said compound.
[0122] Another class of compounds for use in a preferred embodiment
of the present invention has the following structure: 9
[0123] where
[0124] R.sub.2* is H or F;
[0125] R.sub.8 is H, or lower alkyl of 1 to 6 carbons, and
[0126] R.sub.14 is selected from the group consisting of phenyl,
and 4-(lower-alkyl)phenyl, where lower alkyl has 1 to 6 carbons, or
a pharmaceutically acceptable salt of said compound.
[0127] Another preferred compound class has the following
structure: 10
[0128] where R.sub.8 is H, lower alkyl of 1 to 6 carbons, or a
pharmaceutically acceptable salt of said compound.
[0129] Yet another preferred compound is one having the following
structure: 11
[0130] where R.sub.8 is H, lower alkyl of 1 to 6 carbons, or a
pharmaceutically acceptable salt of said compound. When R.sub.8 is
H, this compound is termed AGN 193109.
[0131] Yet another class of compounds contemplated for use in the
present invention is that having the structure: 12
[0132] wherein
[0133] X.sub.1 is: --C(R.sub.1).sub.2--, --C(R.sub.1).sub.2--,
--C(R.sub.1).sub.2--, --S--, --O--, --NR.sub.1--,
--C(R.sub.1).sub.2--O--- , --C(R.sub.1).sub.2--S--, or
C(R.sub.1).sub.2--NR.sub.1--; and
[0134] R.sub.1 is independently H or alkyl of 1 to 6 carbons;
and
[0135] R.sub.2 is optional and is defined as lower alkyl of 1 to 6
carbons, F, Cl, Br, I, CF.sub.3, fluoro substituted alkyl of 1 to 6
carbons, OH SH, alkoxy of 1 to 6 carbons, or alkylthio of 1 to 6
carbons; and
[0136] m is an integer between, and including, 0 and 4; and
[0137] n is an integer between, and including, 0 and 2; and
[0138] o is an integer between, and including, 0 and 3; and
[0139] R.sub.3 is H, lower alkyl of 1 to 6 carbons, F, Cl, Br or I;
and
[0140] R.sub.4 is (R.sub.5).sub.p-phenyl, (R.sub.5).sub.p-naphthyl,
(R.sub.5).sub.p-heteroaryl where the heteroaryl group is
five-membered or 6-membered and has 1 to 3 heteroatoms selected
from the group consisting of O, S, and N; and
[0141] p is an integer between, and including, 0 and 5; and
[0142] R.sub.5 is optional and is defined as independently F, Cl,
Br, I, NO.sub.2, N(R.sub.8).sub.2, N(R.sub.8)COR.sub.8,
N(R.sub.8)CON(R.sub.8).s- ub.2, OH, OCOR.sub.8, OR.sub.8, CN, COOH,
COOR.sub.8, an alkyl group having from 1 to 10 carbons, an alkenyl
group having from 1 to 10 carbons and 1 to three double bonds,
alkynyl group having from 1 to 10 carbons and 1 to 3 triple bonds,
or a (trialkyl)silyl or (trialkyl)silyloxy group where the alkyl
groups independently have from 1 to 6 carbons; and
[0143] Y is a phenyl or naphthyl group, or a heteroaryl selected
from the group consisting of pyridyl, thienyl, furyl, pyridazinyl,
pyrimidinyl, pyrazinyl, thiazolyl, oxazolyl, imidazolyl and
pyrrazolyl, said phenyl and heteroaryl groups being optionally
substituted with one or two R.sub.2 groups, or Y is
--(CR.sub.3.dbd.CR.sub.3).sub.r--; and
[0144] r is an integer between, and including, 1 and 3; and
[0145] A is (CH.sub.2).sub.q where q is an integer from 0-5, lower
branched chain alkyl having from 3 to 6 carbons, cycloalkyl having
from 3 to 6 carbons, alkenyl having from 2 to 6 carbons and 1 or 2
double bonds, alkenyl having from 2 to 6 carbons and 1 or 2 triple
bonds, with the proviso that when Y is
--(CR.sub.3.dbd.CR.sub.3).sub.r--, then A is (CH.sub.2).sub.q and q
is O; and
[0146] B is H, COOH or a pharmaceutically acceptable salt thereof,
COOR.sub.8, CONR.sub.9R.sub.10,--CH.sub.2OH, CH.sub.2OR.sub.11,
CH.sub.2OCOR.sub.11, CHO, CH(OR.sub.12).sub.2,
CHOR.sub.13O,--COR.sub.7, CR.sub.7(OR.sub.12).sub.2,
CR.sub.7OR.sub.13O, or Si(C.sub.1-6alkyl).sub.- 3, wherein R.sub.7
is an alkyl, cycloalkyl or alkenyl group containing 1 to 5 carbons,
R.sub.8 is an alkyl group of 1 to 10 carbons or
(trimethylsilyl)alkyl, where the alkyl groups has 1 to 10 carbons,
or a cycloalkyl group of 5 to 10 carbons, or R.sub.8 is phenyl or
lower alkylphenyl, R.sub.9 and R.sub.10 independently are H, a
lower alkyl group of 1 to 10 carbons, or a cycloalkyl group of 5-10
carbons, or phenyl or lower alkylphenyl, R.sub.11 is lower alkyl,
phenyl or lower alkylphenyl, R.sub.12 is lower alkyl, and R.sub.13
is a divalent alkyl radical of 2-5 carbons. A non-exclusive list of
compounds falling within this description, and methods for making
this class of compounds are disclosed in U.S. Pat. No. 5,728,846 to
Vuligonda et al., the disclosure of which is hereby incorporated by
reference as part of this application.
[0147] Also useful in the present invention are compounds of the
formula:
Y.sub.3(R.sub.4)--X--Y.sub.1(R.sub.1R.sub.2)-Z-Y.sub.2(R.sub.2)-A-B
[0148] Where
[0149] Y.sub.1 is phenyl, naphthyl, or heteroaryl selected from the
group consisting of pyridyl, thienyl, furyl, pyridazinyl,
pyrimidinyl, pyrazinyl, thiazonyl, ozazolyl, imidazolyl, and
pyrrazolyl, said phenyl, naphthyl, and heteroaryl groups being
substituted with an R.sub.1 group, and further substituted or
unsubstituted with one or two R.sub.2 groups;
[0150] R.sub.1 is C.sub.1-10alkyl, 1-ademantyl,
2-tetrahydropyranoxy, trialkylsilanyloxy where alkyl has up to 6
carbons, OH, alkoxy where the alkyl group has up to 10 carbons,
alkylthio where the alkyl group has up to 10 carbons, or
OCH.sub.2OC.sub.1-6 alkyl;
[0151] R.sub.2 is lower alkyl of 1 to 6 carbons, F, Cl, Br, I,
CF.sub.3, CF.sub.2CF.sub.3, OH, OR.sub.3, NO.sub.2,
N(R.sub.3).sub.2, CN, N.sub.3, COR.sub.3, NHCOR.sub.3, COOH, or
COOR.sub.3;
[0152] X is (C(R.sub.3).sub.2, S, SO, SO.sub.2, O or NR.sub.3;
[0153] Z is
[0154] --C.ident.C--,
[0155] --N.dbd.N--,
[0156] --N(O).dbd.N--,
[0157] --N.dbd.N(O)--,
[0158] --N.dbd.CR.sub.3--,
[0159] --CR.sub.3.dbd.N,
[0160] --(CR.sub.3.dbd.CR.sub.3).sub.n-- where n is an integer
having the value 0-5,
[0161] --CO--NR.sub.3--,
[0162] --CS--NR.sub.3--,
[0163] --NR.sub.3--CO,
[0164] --NR.sub.3--CS,
[0165] --COO--,
[0166] --OCO--;
[0167] --CSO--;
[0168] --OCS--; or
[0169] --CO--CR.sub.3.dbd.R.sub.3--O,
[0170] R.sub.3 is independently H or lower alkyl of 1 to 6
carbons;
[0171] Y.sub.2 is a phenyl or naphthyl group, or heteroaryl
selected from a group consisting of pyridyl, thienyl, furyl,
pyridazinyl, pyrimidinyl, pyrazinyl, thiazolyl, oxazolyl,
imidazolyl and pyrrazolyl, said phenyl, naphthyl and heteroaryl
groups being unsubstituted or substituted with one or two R.sub.2
groups, or
[0172] when Z is --(CR.sub.3.dbd.CR.sub.3).sub.n-- and n is 3, 4 or
5 then Y.sub.2 represents a direct valence bond between said
--(CR.sub.3.dbd.CR.sub.3).sub.n, group and B;
[0173] Y.sub.3 is phenyl, naphthyl, or heteroaryl selected from a
group consisting of pyridyl, thienyl, furyl, pyridazinyl,
pyrimidinyl, pyrazinyl, thiazolyl, oxazolyl, imidazolyl and
pyrrazolyl, said phenyl, naphthyl and heteroaryl groups being
unsubstituted or substituted with one to three R.sub.4 groups,
where R.sub.4 is alkyl of 1 to 10 carbons, fluoro-substituted alkyl
of 1 to 10 carbons, alkenyl of 2 to 10 carbons and having 1 to 3
triple bonds, F, Cl, Br, I, NO.sub.2, CN, NR.sub.3, N.sub.3, COOH,
COOC.sub.1-6 alkyl, OH, SH, OC.sub.1-6 alkyl, and SC.sub.1-6
alkyl;
[0174] A is (CH.sub.2).sub.q where q is from 0-5, lower branched
alkyl having 3-6 carbons, cycloalkyl having 3-6 carbons, alkenyl,
having 2-6 carbons and 1-2 double bonds, alkynyl having 2-6 carbons
and 1 to 2 triple bonds, and B is hydrogen, COOH or a
pharmaceutically acceptable salt thereof, COOR.sub.8,
CONR.sub.9R.sub.10, --CH.sub.2OH, CH.sub.2OR.sub.11,
CH.sub.2OCOR.sub.11, CHO, CH(OR.sub.12).sub.2, CHOR.sub.13O,
--COR.sub.7, CR.sub.7(OR.sub.12).sub.2, CR.sub.7OR.sub.13O, or
Si(C.sub.1-6 alkyl).sub.3, where R.sub.7 is an alkyl, cycloalkyl or
alkenyl group containing 1 to 5 carbons, R.sub.8 is an alkyl group
of 1 to 10 carbons or trimethylsilylalkyl where the alkyl group has
1 to 10 carbons, or a cycloalkyl group of 5 to 10 carbons, or
R.sub.8 is phenyl or lower alkylphenyl, R.sub.9 and R.sub.10
independently are hydrogen, an alkyl group of 1 to 10 carbons, or a
cycloalkyl group of 5-10 carbons, or phenyl or lower alkylphenyl,
R.sub.11 is lower alkyl, phenyl or lower alkylphenyl, R.sub.12 is
lower alkyl, and R.sub.13 is divalent alkyl radical of 2-5 carbons,
or a pharmaceutically acceptable salt of said compound. These
compounds are disclosed in U.S. patent application Ser. No.
08/840,040, to Song et al., which application shares common
ownership with the present application and is incorporated by
reference herein in its entirety.
[0175] Additional RAR antagonists or inverse agonists are described
in U.S. patent application Ser. No. 08/845,019, to Song and
Chandraratna, which is incorporated by reference herein in its
entirety; this application shares common ownership with the present
application. Also, compounds useful in the methods of the present
invention are disclosed in International Application Publication
No. WO 94/14777, to Yoshimura et al., which is also incorporated by
reference herein in its entirety. This latter application discloses
RAR antagonists. A non-exclusive list of the structures of some
preferred compounds disclosed therein can be found in FIG. 1
hereof.
[0176] Furthermore, the structures of additional compounds useful
in the present invention are disclosed below. A. 13
[0177] where n is an integer from 1 to 10. 14
[0178] where n is an integer from 1 to 10. 15
[0179] A particularly preferred subgroup of RAR antagonists or
inverse agonists is the set of those RAR antagonists or inverse
agonists that lack antagonist or inverse agonist activity at one or
more subclass of RARs, such as the RAR.alpha., RAR.beta., or
RAR.gamma. receptors; such "subclass-specific" activity may result
in the minimization of toxicity of the drug. Such compounds may
have activity only at the RAR.alpha., RAR.beta., or RAR.gamma.
receptors, or at any combination of these (other than at all of
them). Determination of whether a compound has subclass-specific
specific inverse agonist activity is done through translational
screening as disclosed in U.S. patent application Ser. No.
09/042,943, to Klein et al., and Ser. No. 09/108,298, to Nagpal et
al., both of which are incorporated by reference herein in their
entirety.
[0180] The compounds disclosed herein clearly suggest the synthesis
and use of other compounds structurally similar to these, for use
in the methods of the present invention. In addition to the
compounds referred to herein, other agents that have RAR antagonist
and/or inverse agonist activity are also anticipated to arrest
spermatogenesis in mammals and thus be useful as male contraceptive
agents in the invention of the present application.
[0181] The effective agents of the present invention may be
provided orally, as in a liquid, syrup, suspension, tablet,
capsule, gelatin-coated formulation or the like. Additionally, the
contraceptive agents of the present invention have been
demonstrated to be effective when applied topically. Topical
delivery means include creams, gels, lotions, emulsions,
suspensions, skin patches and the like. Additional delivery means
may include inhalants, suppositories, and nasal sprays.
Time-release formulations may be made for either oral or topical
delivery.
[0182] For therapeutic applications in accordance with the present
invention the antagonist compounds are incorporated into
pharmaceutical compositions, such as tablets, pills, capsules,
solutions, suspensions, creams, ointments, gels, salves, lotions
and the like, using such pharmaceutically acceptable excipients and
vehicles which per se are well known in the art. For example,
preparation of topical formulations are well described in
Remington's Pharmaceutical Science, Edition 17, Mack Publishing
Company, Easton, Pa; incorporated by reference herein. For topical
application, the RAR antagonist or inverse agonist compounds could
also be administered as a powder or spray, particularly in aerosol
form. If the drug is to be administered systemically, it may be
prepared as a powder, pill, tablet or the like or as a syrup or
elixir suitable for oral administration. For intravenous or
intraperitoneal administration, the drug compound will be prepared
as a solution or suspension capable of being administered by
injection. In certain cases, it may be useful to formulate the
antagonist compounds by injection. In certain cases, it may be
useful to formulate the antagonist compounds in suppository form or
as extended release formulation for deposit under the skin or
intramuscular injection.
[0183] The antagonist or inverse agonist compounds will be
administered in a therapeutically effective dose in accordance with
the invention. A therapeutic concentration will be that
concentration which is effective to cause diminution or cessation
of spermatogenesis in the testes of the male mammal. It is
currently thought that a formulation containing between about 0.5
and about 0.001 mg/kg of body weight, more preferably between about
0.3 mg/kg and 0.005 mg/kg, even more preferably about 0.075 mg/kg
of body weight and about 0.01 mg/kg of body weight will constitute
a therapeutically effective concentration for oral application,
with routine experimentation providing adjustments to these
concentrations for other routes of administration if necessary.
[0184] Accordingly, in one embodiment the present invention
comprises a method of inhibiting spermatogenesis in a mammal
comprising the administration of an effective amount of an RAR
antagonist or RAR inverse agonist at time intervals sufficient to
inhibit or arrest spermatogenesis. In a further embodiment, the
mammal is a human.
[0185] In a further preferred embodiment, the RAR antagonist or RAR
inverse agonist is administered orally through the use of a liquid,
syrup, suspension, tablet, capsule, or gelatin-coated formulation.
In another preferred embodiment, the RAR antagonist or RAR inverse
agonist is topically administered, through the use of means
including a patch, cream, lotion, emulsion, or gel. In yet another
embodiment, the RAR antagonist or RAR inverse agonist is formulated
in an inhalant, suppository or nasal spray.
DETAILED DESCRIPTION OF THE INVENTION
[0186] The present invention concerns compositions and methods for
the prophylactic prevention of pregnancy by the inhibition or
arrest of spermatogenesis in male mammals. Spermatogenesis occurs
in the seminiferous tubules of the testes of sexually mature male
mammals. These tubules consist of a basement membrane surrounding
an intra-tubule lumen. Specialized columnar cells termed Sertoli
cells lie against the basement membrane and protrude into the
lumen; the germ cells remain closely associated with the Sertoli
cells throughout spermatogenesis.
[0187] Spermatogonia, male gamete stem cells, lie between the
Sertoli cells and the basement membrane. Mitosis of a
spermatogonium gives rise to two daughter cells; one may remain
near the basement membrane as a spermatogonium and the other may
develop, through subsequent rounds of mitosis, into a primary
spermatocyte. As it develops the cells that become diploid primary
spermatocytes are crowded closer to the tubule lumen.
[0188] The primary spermatocyte then enters meiosis and gives rise
to haploid spermatids. These spermatids remain closely associated
with the Sertoli cell, now at a location close to the lumen, and
undergo a metamorphosis mediated partly by the Sertoli cell,
maturing into spermatozoa. These cells are then released into the
lumen of the seminiferous tubule.
[0189] The seminiferous tubules are closely packed together in the
testes, being separated by connective tissue containing fibrocytes
and vessels. An inhabitant of the spaces between the tubules is a
steroidogenic somatic cell termed the Leydig cell. These cells
synthesize the steroid hormone testosterone, which is an important
stimulus for the differentiation of germ cells; the hormone
diffuses into the seminiferous tubules where it stimulates
spermatogenesis.
[0190] The time course of complete spermatogenesis is long;
approximately 64 days in humans and 54 days in rats. This time
course can be divided into 4 stages. In the first stage,
spermatocytogenesis, the spermatogonia divide and give rise to
primary spermatocytes. In the second stage, the primary
spermatocytes undergo meosis and give rise to spermatids. In the
third stage, spermoigenesis, the spermatids metamorphize into
spermatozoa. In the final stage, maturation, the spermatozoa mature
and are released into the seminiferous tubule. The spermatozoa
undergo final maturation in the epiphysis. Cells in each of these
four stages can be seen as "layers" in normal seminiferous tubules,
with the least mature cells nearer the basement membrane, and the
most mature cells near the lumen. The absence of cells of one or
more stage is indicative of an event blocking or arresting a stage
in spermatogenesis.
[0191] Although the exact mechanism underlying hormonal and gene
regulation occurring in spermatogenesis is not precisely known, and
the scope of the present invention is not to be limited by theory,
it is believed that testosterone production is regulated by the
pituitary hormone, luteinizing hormone (LH). Another pituitary
hormone, follicle-stimulating hormone (FSH), is also involved in
the regulation of spermatogenesis, with primary hormone receptors
being present on the Sertoli cells. One effect of FSH on Sertoli
cells is to stimulate the production of androgen-binding protein
(ABP), which has a high binding affinity for testosterone and helps
retain the steroid within the seminiferous tubules and sustain its
effect on spermatogenesis.
[0192] Another peptide, termed inhibin, is thought to be secreted
by Sertoli cells in response to the binding of FSH. Inhibin, in
turn, appears to act on target cells within the pituitary to
inhibit FSH secretion. Thus, inhibin may operate to act as a
negative feedback regulator for the release of FSH and thus the
production of ABP, with one consequence being the prevention of
overstimulation by testosterone. Overproduction of inhibin could
serve to lower the concentration of testosterone within the
seminiferous tubules.
[0193] Thus, the regulation of spermatogenesis appears to include
the regulation of gene expression and synthesis of a number of
factors that either act as peptide hormones themselves or are
involved in the sequestration or regulation of hormones important
in spermatogenesis. Retinoid nuclear receptors (retinoic acid
receptors (RAR) and retinoid X receptors (RXR)) are known to be
involved in the ligand-mediated transcriptional regulation of
various genes, which may include some of these factors.
[0194] The following examples are intended to illustrate further
embodiments of the present invention and do not limit the scope of
the invention, which is defined solely by the claims concluding
this specification.
EXAMPLE 1
Oral Treatment of Spague-Dawley Rats with AGN 194310
[0195] Ninety-eight male and ninety-eight female Sprague-Dawley
(Crl:CD.RTM.(SD) IGS BR) Charles River, Hollister, Calif. 95023)
rats, approximately 8 to 10 weeks old, were used for the study. The
rats were divided into the following groups: non-treated control,
vehicle control, 0.005 mg/kg/day, 0.015 mg/kg/day and 0.15
mg/kg/day AGN 194310. AGN 194310 has the following chemical
structure: 16
[0196] This compound,
4-[[4-(4-ethylphenyl)-2,2-dimethyl-(2H)-thiochromen--
6-yl]-ethynyl]-benzoic acid, may be synthesized using conventional
organic synthetic means. The following reaction scheme is
Applicants' currently preferred method of making this compound.
[0197] Step 1: A heavy-walled screw cap tube was charged with
3-methyl-2-butenoic acid (13.86 g, 138.4 mmol), 4-methoxy
thiophenol (20.0 g, 138.4 mmol), and piperidine (3.45 g, 41.6
mmol). This mixture was heated to 105.degree. C. for 32 hours,
cooled to room temperature and dissolved in EtOAc (700 mL). The
resulting solution was washed with 1M aqueous HCl, H.sub.2O, and
saturated aqueous NaCl before being dried over Na.sub.2SO.sub.4.
Concentration of the dry solution under reduced pressure afforded
an oil which upon standing in the freezer provided a crystalline
solid. 3-(4-methoxy-phenylsulfanyl)-3-methyl-butyric acid was
isolated as pale-yellow crystals by washing the crystalline solid
with pentane. (27.33 g, 82%). .sup.1H NMR (300 MHz, CDCl.sub.3)
.delta.: 7.48 (2H, d, J=9.0 Hz), 6.89 (2H, d, J=8.9 Hz), 3.83 (3H,
s), 2.54 (2H, s), 1.40 (6H, s).
[0198] Step 2: To a solution of
3-(4-methoxy-phenylsulfanyl)-3-methyl-buty- ric acid (20.0 g, 83.2
mmol) in 250 mL of benzene at room temperature was added a solution
of oxalyl chloride (15.84 g, 124.8 mmol) in 10 mL of benzene over
30 minutes. After 4 hours the solution was washed with ice cold 5%
aqueous NaOH (CAUTION: a large volume of gas is released during
this procedure), followed by ice cold H.sub.2O, and finally
saturated aqueous NaCl. The solution was dried (Na.sub.2SO.sub.4)
and concentrated under reduced pressure to give a clear yellow oil.
This material was used without further purification in the next
step.
[0199] .sup.1H NMR (300 MHz, CDCl.sub.3) .delta.: 7.45 (2H, d,
J=8.8 Hz), 6.90 (2H, d, J=8.8 Hz), 3.84 (3H, s), 3.12 (2H, s), 1.41
(6H, s). Step 3: To a solution of the acyl chloride product of Step
2 (21.5 g, 83.2 mmol) in 250 mL of CH.sub.2Cl.sub.2 at 0.degree. C.
was added dropwise a solution of SnCl.sub.4 (21.7 g, 83.2 mmol) in
30 mL of CH.sub.2Cl.sub.2. After 2 hours the reaction was quenched
by slow addition of 150 mL H.sub.2O. The organic layer was washed
with 1M aqueous HCl, 5% aqueous NaOH, H.sub.2O, and finally
saturated aqueous NaCl before being dried over MgSO.sub.4.
Concentration under reduced pressure and vacuum distillation of the
residual oil (Bulb-to-bulb, 125-135.degree. C., 5 mm/Hg) afforded
14.48 g (78%) of 6-methoxy-2,2-dimethyl-thiochroman-4-one as a
pale-yellow oil. .sup.1H NMR (300 MHz, CDCl.sub.3) .delta.: 7.62
(1H, d, J=2.9 Hz), 7.14 (1H, d, J=8.6 Hz), 7.03 (1H, dd, J=2.8, 8.3
Hz), 3.83 (3H, s), 2.87 (2H, s), 1.46 (6H, s).
[0200] Step 4: To a solution of
6-methoxy-2,2-dimethyl-thiochroman-4-one (6.0 g, 27 mmol) in 50 mL
CH.sub.2Cl.sub.2 cooled to -23.degree. C. was added BBr.sub.3 (20.0
g, 80.0 mmol; 80.0 mL of a 1M solution in CH.sub.2Cl.sub.2) over a
20 minute period. After stirring for 5 hours at -23.degree. C. the
solution was cooled to -78.degree. C. and quenched by the slow
addition of 50 mL of H.sub.2O. Upon warming to room temperature the
aqueous layer was extracted with CH.sub.2Cl.sub.2 and the combined
organic layers were washed with saturated aqueous NaHCO.sub.3,
H.sub.2O, and saturated aqueous NaCl before being dried over
MgSO.sub.4 Removal of the solvents under reduced pressure gave a
green-brown solid which upon recrystalization (Et.sub.2O/hexanes)
afforded 2.25 g (40%) of 6-hydroxy-2,2-dimethylthiochroman-4-one as
a light brown solid. .sup.1H NMR (300 MHz, CDCl.sub.3) .delta.:7.63
(1H, d, J=2.8 Hz), 7.15 (1H, d, J=8.5 Hz), 7.01 (1H, dd, J=2.8, 8.5
Hz), 2.87 (2H, s), 1.46 (6H, s).
[0201] Step 5: To a solution of
6-hydroxy-2,2-dimethylthiochroman-4-one (165.0 mg, 0.79 mmol) in
5.0 mL of anhydrous pyridine at 0.degree. C. was added
trifluoromethanesulfonic anhydride (245.0 mg, 0.87 mmol). After 4
hours at 0.degree. C. the solution was concentrated and the
residual oil dissolved in Et.sub.2O, washed with H.sub.2O followed
by saturated aqueous NaCl, and dried over MgSO.sub.4. Removal of
the solvents under reduced pressure and column chromatography (5%
EtOAc/hexanes) afforded 126.0 mg (47%) of
2,2-Dimethyl-4-oxo-thiochroman-6-yl trifluoromethanesulfonate as a
colorless solid. .sup.1H NMR (300 MHz, CDCl.sub.3) .delta.:7.97
(1H, s), 7.32 (2H, s), 2.90 (2H, s), 1.49 (6H, s).
[0202] Step 6: A solution of 2,2-dimethyl4-oxo-thiochroman-6-yl
trifluoromethanesulfonate (2.88 g, 8.50 mmol) in 10 mL Et.sub.3N
and 20.0 mL DMF was sparged with argon for 10 minutes. To this
solution was added trimethylsilylacetylene (4.15 g, 42.0 mmol) and
bis(triphenylphosphine)-p- alladium(II) chloride (298.0 mg, 0.425
mmol). The solution was heated to 95.degree. C. for 5 hours, cooled
to room temperature, and diluted with H.sub.2O. Extraction with
EtOAc was followed by washing the combined organic layers with
H.sub.2O and saturated aqueous NaCl and drying over MgSO.sub.4.
Concentration of the dry solution under reduced pressure and
isolation of the product by column chromatography (3%
EtOAc/hexanes) afforded 2.23 g (91%) of the
2,2-dimethyl-6-trimethylsilanylethynyl-thioc- hroman-4-one as an
orange oil. .sup.1H NMR (300 MHz, CDCl.sub.3) .delta.: 8.18 (1H, d,
J=1.9 Hz), 7.34 (1H, dd, J=1.9, 8.1 Hz), 7.15 (1H, d, J=8.1 Hz),
2.85 (2H, s), 1.45 (6H, s), 0.23 (9H, s).
[0203] Step 7: A solution of
2,2-dimethyl-6-trimethylsilanylethynyl-thioch- roman-4-one (110.0
mg, 0.38 mmol) and K.sub.2CO.sub.3 (40.0 mg, 0.29 mmol) in 10.0 mL
MeOH was stirred overnight at room temperature. The solution was
diluted with H.sub.2O and extracted with Et.sub.2O. The combined
organic layers were washed with H.sub.2O and saturated aqueous NaCl
and dried over MgSO.sub.4. Removal of the solvent under reduced
pressure afforded 81 mg (99%) of the
6-ethynyl-2,2-dimethylthiochroman-4-one as an orange oil. .sup.1H
NMR (300 MHz, CDCl.sub.3) .delta.:8.20 (1H, d, J=1.9 Hz), 7.46 (1H,
dd, J=1.9, 8.1 Hz), 7.18 (1H, d, J=8.1 Hz), 3.08 (1H, s), 2.86 (2H,
s), 1.46 (6H, s).
[0204] Step 8: A solution of
6-ethynyl-2,2-dimethylthiochroman-4-one (82.0 mg, 0.38 mmol) and
ethyl 4-iodobenzoate (104.9 mg, 0.38 mmol) in 5.0 mL Et.sub.3N was
purged with argon for 10 minutes. To this solution were added
bis(triphenylphosphine)-palladium(II) chloride (88.0 mg, 0.12 mmol)
and copper(I) iodide (22.9 mg, 0.12 mmol). After sparging for an
additional 5 minutes with argon, the solution was stirred overnight
at room temperature. The reaction mixture was filtered through a
pad of Celite using an Et.sub.2O wash. Concentration of the
filtrate under reduced pressure, followed by column chromatography
of the residual solid, afforded 100 mg (72%) of ethyl
4-[(2,2-dimethyl-4-oxo-thiochroman-- 6-yl)ethynyl]-benzoate as a
yellow solid. .sup.1H NMR (300 MHz, CDCl.sub.3) .delta.: 8.25 (1H,
d, J=1.8 Hz), 8.00 (2H, d, J=8.4 Hz), 7.55 (2H, d, J=8.4 Hz), 7.53
(1H, dd, J=1.8, 8.2 Hz), 7.21 (1H, d, J=8.2 Hz), 4.37 (2H, q, J=7.1
Hz), 2.88 (2H, s), 1.47 (6H, s), 1.39 (3H, t, J=7.1 Hz).
[0205] Step 9: A solution of sodium bis(trimethylsilyl)amide (1.12
g, 6.13 mmol) in 16.2 mL of THF was cooled to -78.degree. C. and a
solution of ethyl
4-(2,2-dimethyl-4-oxo-thiochroman-6-ylethynyl)-benzoate (1.86 g,
5.10 mmol) in 15.0 mL was added slowly. After 30 minutes a solution
of 2-[N,N-bis(trifluoromethanesulfonyl)amino]-5-pyridine (2.40 g,
6.13 mmol) in 10 mL of THF was added. After 5 minutes the solution
was warmed to room temperature and stirred overnight. The reaction
was quenched by the addition of saturated aqueous NH.sub.4Cl and
extracted with EtOAc. The combined organic layers were washed with
5% aqueous NaOH and H.sub.2O before being dried (MgSO.sub.4) and
concentrated under reduced pressure. Ethyl
4-((2,2-dimethyl-4-trifluoromethanesulfonyloxy-(2H)-thiochromen-6-y-
l)ethynyl)-benzoate, 1.53 g (61%), was isolated by column
chromatography (2% EtOAc/hexanes) as a yellow solid. .sup.1H NMR
(300 MHz, CDCl.sub.3) .delta.: 8.03 (2H, d, J=8.4 Hz), 7.61 (1H, d,
J=1.8 Hz), 7.59 (2H, d, J=8.4 Hz), 7.41 (1H, dd, J=1.8, 8.1 Hz),
7.29 (1H, d, J=8.1 Hz), 5.91 (1H, s), 4.39 (2H, q, J=7.1 Hz), 1.53
(6H, s), 1.41 (3H, t, J=7.1 Hz).
[0206] Step 10: A solution of 4-ethylbromobenzene (670.9 mg, 3.63
mmol) in 4.0 mL of THF was cooled to -78.degree. C. and
tert-butyllithium (464.5 mg, 7.25 mmol, 4.26 mL of a 1.7M solution
in pentane) was added to give a yellow solution. After 30 minutes a
solution of ZnCl.sub.2 (658.7 mg, 4.83 mmol) in 8.0 mL THF was
slowly added via cannula. The resulting solution was warmed to room
temperature and transferred via cannula to a solution of ethyl
4-(2,2-dimethyl-4-trifluoromethanesulfonyloxy-(2H)-thio-
chromen-6-ylethynyl)-benzoate (1.20 g, 2.42 mmol) and
tetrakis(triphenylphosphine)palladium(0) (111.7 mg, 0.097 mmol) in
8.0 mL THF. This solution was heated to 50.degree. C. for 1 hour,
cooled to room temperature, and the reaction quenched by the
addition of saturated aqueous NH.sub.4Cl. The solution was
extracted with EtOAc and the combined organic layers were washed
with H.sub.2O and saturated aqueous NaCl before being dried
(MgSO.sub.4) and concentrated under reduced pressure. Ethyl
4-[[4-(4-ethylphenyl)-2,2-dimethyl-(2H)-thiochromen-6-yl]-
-ethynyl]-benzoate was isolated by column chromatography (5%
EtOAc/hexanes) as a colorless oil. .sup.1H NMR (300 MHz,
CDCl.sub.3) .delta.: 7.99 (2H, d, J=8.2 Hz), 7.52 (2H, d, J=8.4
Hz), 7.40 (5H, m), 7.35 (2H, m), 5.85 (1H, s), 4.38 (2H, q, J=7.1
Hz), 2.72 (2H, q, J=7.6 Hz), 1.48 (6H, s), 1.40 (3H, t, J=7.1 Hz),
1.30 (3H, t, J=7.6 Hz).
[0207] Step 11: To a solution of ethyl
4-[[4-(4-ethylphenyl)-2,2-dimethyl--
(2H)-thiochromen-6-yl]-ethynyl]-benzoate (940.0 mg, 2.08 mmol) in
10.0 mL THF and 5.0 mL EtOH was added NaOH (416.0 mg, 10.4 mmol,
5.2 mL of a 2M aqueous solution). The resulting solution was
stirred overnight at room temperature. The reaction mixture was
acidified with 10% aqueous HCl and extracted with EtOAc. The
combined organic layers were washed with H.sub.2O, saturated
aqueous NaCl, and dried (Na.sub.2SO.sub.4) before removing the
solvent under reduced pressure. The residual solid was
recrystallized from CH.sub.3CN to give 786.0 mg (89%) of
4-[[4-(4-ethylphenyl)-2,2-dimethyl-(2H)-thiochromen-6-yl]-ethynyl]-benzoi-
c acid as a colorless solid. .sup.1H NMR (300 MHz, d.sub.6-acetone)
.delta.: 8.01 (2H, d, J=8.3 Hz), 7.60 (2H, d, J=8.5 Hz), 7.42 (2H,
m), 7.29 (2H, m), 7.22 (3H, m), 5.94 (1H, s), 2.69 (2H, q, J=7.7
Hz), 1.47 (6H, s), 1.25 (3H, t, J=7.7 Hz). This compound, the final
desired product, was termed AGN 194310.
[0208] The AGN 194310 compound was provided as follows: the
compound was dissolved in capric/caprylic triglyceride (CCT) at a
variety of doses, either 0.001% (v/v) AGN 194310, 0.003% (v/v) AGN
194310, or 0.01% (v/v) AGN 194310. Control animals received the CCT
vehicle without the AGN 194310 active ingredient (AGN 194310
Vehicle). Although many retinoids and retinoid analogs are light
labile, this compound is relatively stable to normal light.
[0209] Newly arrived animals were quarantined for at least 7 days
prior to their use in the study. All animals used in the study
appeared to be in good health, with no evidence of disease or
physical abnormality.
[0210] One hundred ninety-six animals were distributed into
thirteen groups as follows: Groups 1 through 5 were Main Study
groups. Groups 6-9 were used for Toxicokinetic studies. Groups
10-13 were Main Study Recovery groups. The characteristics of each
group are shown in Table 1 below.
1TABLE 1 Total Daily Total Daily Amount of Amount of Test Prep.
Group Number Test AGN 194310 (ml/kg/ No. & Sex Material
(mg/kg/day) day) 1 10M/10F Non-Treated Control N/A N/A 2 10M/10F
AGN 194310 Vehicle N/A 1.5 3 10M/10F 0.001% AGN 194310 0.005 0.5 4
10M/10F 0.003% AGN 194310 0.015 0.5 5 10M/10F 0.01% AGN 194310 0.15
1.5 6 4M/4F AGN 194310 Vehicle N/A 1.5 7 8M/8F 0.001% AGN 194310
0.005 0.5 8 8M/8F 0.003% AGN 194310 0.015 0.5 9 8M/8F 0.01% AGN
194310 0.15 1.5 10 5M/5F AGN 194310 Vehicle N/A 1.5 11 5M/5F 0.001%
AGN 194310 0.005 0.5 12 5M/5F 0.003% AGN 194310 0.015 0.5 13 5M/5F
0.01% AGN 194310 0.15 1.5
[0211] The drug was administered using a graduated syringe and a
20.times.3 inch animal feeding needle. Drug was given to each
animal in a single dose per day. Animals were observed at lease
once daily during the course of the study for mortality, general
health, behavior and any apparent physical or pharmacological
abnormalities.
[0212] Animals were weighed on the first day of the study and once
per week thereafter, and the body weights recorded. The body
weights were used for the dosage calculations. For all the Main
Study and Recovery animals, food (Purina Certified Rodent Chow,
meal form) was placed into tared glass jars and left in the animal
cages. Jars were removed and weighed once weekly. Food was added to
the jars when necessary. Food consumption was not recorded for the
animals used in the toxicokinetic satellite studies.
[0213] Urine was collected from animals in the Main Study and
Recovery groups during week 4 of the treatment period, and from
Recovery group animals during week 4 of the recovery period. Urine
was analyzed for: blood (hemoglobin and erythrocytes), bilirubin,
color, glucose, ketones, leukocytes, microscopic evaluations of any
urine sediment, nitrate, pH, protein, specific gravity,
transparency, and urobilinogen.
[0214] Blood was collected from animals constituting the Main Study
and Recovery groups at the end of the treatment and recovery
periods, respectively. Before blood collection, the animals were
allowed to fast for 16 hours, then blood was collected from each
animal via cardiac puncture under anesthesia. The animals were
sacrificed thereafter.
[0215] The following tests were performed using the blood samples
collected: hematocrit (total blood cell volume), total hemoglobin,
mean cell volume, mean corpuscular hemoglobin (MCH), mean
corpuscular hemoglobin concentration (MCHC), platelet count, red
blood cell count (RBC), total white blood cell count (WBC), and a
differential WBC count for basophils, eosinophils, lymphocytes,
monocytes, neutrophils.
[0216] The concentration of drug in the blood was determined from
blood drawn from the retro-orbital sinus of the right eye on Day 7
of the study as follows: for rats in groups 7 through 9
(4/sex/group/timepoint, with each animal being bled no more than 3
times), blood (approximately 1 ml) was drawn prior to being given
the drug, and at approximately 2, 6, 8, 12 and 24 hours
post-dosing. The vehicle-treated rats (group 6) were bled at
approximately 8 and 24 hours post-dosing. The rats in groups 6
through 9 were similarly bled on Day 22 of the study, then
euthanized. All blood was drawn into tubes containing EDTA to
prevent coagulation, and placed on ice prior to analysis. The blood
was assayed for the presence of AGN 194310 by gas
chromatography/mass spectrometry.
[0217] Animals were euthanized by inhalation of carbon dioxide. A
complete necropsy was performed on all Main Study and Recovery
group animals that died, or were euthanized due to moribund
conditions, or were euthanized on scheduled sacrifice.
[0218] The following organs were weighed for necroscopized animals:
adrenal glands, ovaries, kidneys, pituitary gland, liver, spleen,
heart, testes, and brain. In the case of organ pairs, both organs
were weighed together.
[0219] The following tissues and organs were isolated, trimmed if
necessary, and preserved in 10% buffered formalin for
histopathological evaluation: adrenal glands, mammary gland (with
skin), aorta, ovaries, bone/bone marrow, pancreas, femur, pituitary
gland, tibia, prostate gland, knee joint, salivary glands, parotid,
brain, sub-maxillary, cervix sciatic nerve, diaphragm, seminal
vesicle, epididymides, skeletal muscle (thigh), eyes, spinal chord
(thoracic), spleen, esophagus, sternum, stomach, testes, duodenum,
thymus, jejunum, thyroid gland with parathyroids, ileum, any
tissues with lesion(s), cecum, tongue, colon, trachea, heart,
bladder, kidneys, uterus, liver, ureter, lungs, urethra, lymph
nodes (vaginal, cervical, mediastinal, mesenteric).
[0220] Target tissues and organs from the Vehicle (control) and
high-dose groups were imbedded in paraffin, and tissue sections
made. The sections were mounted and stained with hematoxylin and
eosin using standard histological techniques; such
histopathological evaluation was performed using techniques well
known in the art.
[0221] After review and comparison of the histological findings
obtained at the end of treatment period in the vehicle alone
control group (group 2) and Main Study high dose (0.15 mg/kg/day)
group (group 5), only those tissues determined to be affected by
the drug at the high dose were evaluated in the Main Study
intermediate (0.015 mg/kg/day) and low dose (0.005 mg/kg/day)
groups (groups 3 and 4, respectively). Similarly, only when
treatment-related histological effects were observed in a given
tissue or dosage group of animals were the affected tissues and
dosage groups evaluated in the Recovery group. In the Recovery
dosage groups that were so evaluated, the selected tissues were
prepared and evaluated as set forth above.
[0222] No treatment-related deaths of study animals occurred during
the course of the study. There were no statistically significant
treatment-related effects on body weight during the treatment or
recovery periods. The mean body weights of all study group animals
were comparable throughout the study period. Nor were there
treatment-related effects on food consumption between animals of
different groups.
[0223] There were no apparent treatment-related effects among
animals of different groups in any urinalysis parameters at the end
of the treatment period. By contrast, urinalysis of Recovery group
animals at the end of the recovery period revealed no spermatozoa
counts in the 0.15 mg/kg/day male rat urine samples. There were no
other treatment-related effects in any other groups at the end of
the recovery period.
[0224] AGN 194310 was systemically absorbed following oral
administration to rats and approached the peak concentration in
plasma (Cmax) at 2 or 6 hours post dosing (Tmax). A dose dependent
increase in systemic exposure to AGN 194310 was observed across the
concentrations of AGN 194310. Similar Cmax and AUC.sub.0-24hr
values (Area Under the Curve from 0 to 24 hours after dosage; this
measures the concentration of drug in the blood during this time
period monitored) were observed when rat blood was tested between
the two collection periods. Pharmacokinetic parameters are
presented in the following table:
2TABLE II 0.001% AGN 194310 0.003% AGN 194310 0.01% AGN 194310
Formulation (dosage) (0.005 mg/kg/day) (0.015 mg/kg/day) (0.15
mg/kg/day) Cmax.sup.a Day 7.sup.c 1.83 .+-. 0.55 4.73 .+-. 1.2 43.1
.+-. 7.2 (ng/ml) Day 22.sup.c 1.97 .+-. 0.75 5.32 .+-. 1.56 42.4
.+-. 9.3 Tmax Day 7.sup.c 2 2 6 (hr) Day 22.sup.c 2 2 6 AUC.sub.24
hr Day 7.sup.c 19.6 .+-. 1.1 57.6 .+-. 2.6 668 .+-. 24 (ng
.multidot. hr/ml).sup.b Day 22.sup.c 20.8 .+-. 1.1 63.6 .+-. 2.7
675 .+-. 25 .sup.aMean .+-. SD (N = 8/dose/time point). .sup.bMean
.+-. SEM (N = 8/dose/time point). .sup.cThe day 7 data were not
statistically different from the day 22 data.
[0225] There were no noticeable differences between study animals
observed during the postmortem pathological examination at the end
of the treatment period. At the end of the recovery period,
postmortem examinations revealed an apparent reduction of testes
size in all five male rats that had been treated with AGN 194310 at
a dosage level of 0.15 mg/kg/day. This finding was supported by a
reduction in testes weight in male rats give the high drug dose
(0.15 mg/kg/day) at the end of the treatment and recovery periods.
Male rats in the other dosage groups showed no statistically
significant reduction of testes weight.
[0226] Histological examination of thin sections of the testes
revealed that all (10/10) of the male rats given the high dose of
AGN 194310 underwent spermatogenic arrest at the end of treatment.
No such effect appeared in males given the intermediate (0.015
mg/kg/day or low (0.005 mg/kg/day) dosages of the drug. The
seminiferous tubules of the high dose males were lined with one to
two layers of germinal cells, rather than the usual four or more
layers seen in normal seminiferous tubules. This change reflects a
complete block of spermatogenesis.
[0227] Leydig cells appeared unaffected, nor was any evidence of an
atrophic change seen in the secondary sex glands, such as the
seminal vesicles and prostate, of the high dose males. In other
words, the drug appears to target the seminiferous epithelium.
Changes in the testes were not readily evident, either through
visual or microscopic inspection at the end of the treatment
period.
[0228] The rats in the Recovery group were permitted approximately
a one-month period without exposure to the drug. In the male rats
of the Recovery group, testicular atrophy was evident and
accompanied morphologically by continuing cessation of
spermatogenesis, monitored according to the criteria and methods
mentioned above. However, reversibility of such inhibition was also
evident, as could be seen by a focal increase in germ cell layers
in individual tubules. The extent of this recovery varied from
animal to animal and within a single testicular section.
[0229] None of the high dose male rats, either in the Main Study
Group or the Recovery group, displayed inflammation or damage to
stromal or vascular elements of the testis. Physiological effects
of drug treatment other than those associated with spermatogenic
arrest were not observed. The epididyrnis of the high dose rats
showed an increase in exfoliated cells at the end of treatment and
the absence of stored epididymal sperm at the end of recovery;
these changes are expected secondary effects of spermatogenic
arrest.
[0230] As the total time course of spermatogenesis is approximately
54 days in rats, the time period required to observe reversibility
of complete spermatogenic arrest would be at least this long. Also,
this time period would be expected to be additionally lengthened,
depending upon the time required for the drug to be clear from the
subject's system. In a separate experiment 88% of the drug was
shown to be excreted within 2 weeks following treatment. Thus, this
experiment provides evidence of reinitiation of spermatogenesis in
animals of the Recovery group.
[0231] Thus, this experiment shows that daily oral delivery of the
RAR antagonist AGN 194310 is sufficient to cause spermatogenic
arrest in mammals, and that the effects of spermatogenic arrest in
treated animals are reversed following cessation of AGN 194310
treatment. Although the exact mechanism of inhibition is not known,
and, while not wishing to be bound by theory, the Applicants
believe that the drug appears especially to affect, either directly
or indirectly, primary spermatocytes. Thus, germ cells that have
differentiated beyond the primary spermatocyte stage when treatment
with an RAR antagonist or inverse agonist is initiated will
continue to mature and differentiate into spermatozoa, while
spermatogonia do not appear to differentiate beyond the primary
spermatocytes stage. Since the 2.sup.nd, 3.sup.rd, and 4.sup.th
stages of spermatogenesis occur over an extended period before the
release of the spermatozoa into the epididymis, this is why
spermatozoa were still seen in the urine of the Main Study male
rats at the end of treatment (despite clear spermatogenic arrest
being visible in the testes tissue sections), while the male rats
of the Recovery group have no detected spermatozoa in their urine
(despite clear indications of renewed spermatogenesis in the testes
of these rats).
[0232] Thus, in this experiment daily oral dosage of an RAR
antagonist (inverse agonist), AGN 194310, at 0.15 mg/kg/day was
sufficient to cause reversible spermatogenic arrest. By presenting
these data the Applicants are not indicating that the experiment
demonstrates an optimal dose, delivery method, or frequency of
treatment. However, this experiment clearly shows the unanticipated
result that an RAR antagonist or inverse agonist may be used as an
effective male contraceptive, as claimed.
EXAMPLE 2
Topical Treatment of Spague-Dawley Rats with AGN 194310
[0233] An experiment was conducted in a manner substantially
similar to that described in Example 1, with the following
differences. Twenty-nine male and twenty-nine female Sprague-Dawley
rats, approximately 7 weeks old were used for the study. Five
rats/sex/group were designated as Main Study animals: (vehicle
control, 0.025 mg/kg/day AGN 194310, and 0.25 mg/kg/day AGN
194310), and 7/sex/group designated as toxicokinetic satellite
animals (0.025 mg/kg/day AGN 194310 and 0.25 mg/kg/day AGN 194310).
No "vehicle alone" control group was made for the toxicokinetic
satellite animals. In this study there was no Recovery group.
[0234] The animals' backs were maintained shaven during the course
of the study for application of the topical cream. The animals were
treated daily with a topical formulation containing either AGN
194310 vehicle cream alone, 0.01% (w/w) AGN 194310 in the same
vehicle cream, or 0.1% (w/w) AGN 194310 in the same vehicle cream.
The vehicle cream consisted of a mixture of the following
ingredients:
3 Benzyl Alcohol 1% (w/w) Medium Chain Triglycerides 25% (w/w)
Carbomer 1342 0.2% (w/w) Sorbitan Monooleate 0.2% (w/w) Carbomer
934P 1% (w/w) EDTA 0.05% (w/w) 5 N Sodium Hydroxide 2.72 (w/w)
Water q.s. to 100% (w/w)
[0235] The following Table shows the experimental design:
4TABLE 3 Total Daily Total Daily Amount of Amount of Group Number
AGN 194310 Test Prep. No. & Sex Test Material (mg/kg/day)
(gm/kg/day) 1 5M/5F Vehicle Cream N/A 0.25 2 5M/5F 0.01% AGN 194310
0.025 0.25 3 5M/5F 0.1% AGN 194310 0.25 0.25 4 7M/7F 0.01% AGN
194310 0.025 0.25 5 7M/7F 0.1% AGN 194310 0.25 0.25
[0236] Daily dosages were calculated using the most recently
obtained body weights, as shown below. The test or control creams
were applied for 28 consecutive days to the shaved back of each
animal in an area approximately equal to 35.5 cm.sup.2. Application
was made using a repeat pipettor, and the drug gently massaged into
the skin. An Elizabethan collar was affixed around each animal's
neck for a period of about 6 hours following treatment to prevent
removal or systemic ingestion of the drug.
[0237] Blood was drawn at day 29 via cardiac puncture, as described
in Example 1. The animals were first permitted to fast for
approximately 16 hours prior to blood collection. Satellite animals
were sacrificed on day 28.
[0238] Topical skin application of AGN 194310 did not result in any
evidence of treatment-related skin irritation. No treatment-related
clinical observations, differences in body weight, differences in
food consumption, or in gross pathology were observed.
[0239] Male rats in all groups displayed no statistically
significant hematological differences versus the control rats.
However, there is a dose-dependent reduction in triglycerides in
the male rats given the drug. Histopathological analysis reveals
atrophy of the seminiferous tubules, with concomitant spermatogenic
arrest in 0 out of 5 male rats in the 0.025 mg/kg/day group and 5
out of 5 male rats in the 0.25 mg/kg/day; spermatogenic arrest was
detected as described in Example 1. Additionally, there was a
notable reduction of germ cells in the head of the epididymis in
the majority of males displaying spermatogenic arrest.
EXAMPLE 3
Reversibility of Spermatogenic Arrest
[0240] This experiment was conducted in a manner substantially
similar to that of Example 1. Groups of male Sprague Dawley rats
were treated orally for 4 weeks with either 0, 0.075, or 0.150
mg/kg/day of AGN 194310. Three to six animals from each group were
sacrificed after 2 weeks of treatment, 6 animals from each group
were sacrificed following 4 weeks of treatment and 6 animals from
each group were sacrificed after 18-23 weeks of subsequent recovery
after cessation of treatment. Histological and pathological
examinations were done of the sacrificed animals, as in Example 1.
Additionally, the animals in the 23 week recovery group were mated
to normal, untreated female Sprague Dawley rats before being
sacrificed to assess the reproductive function.
[0241] As in the previous examples, the control group of rats (no
drug) displayed no abnormal histological or biochemical differences
during the time course of the experiment, except for a single
individual, which was found to have bilateral severe sperm
granulomas due to segmental aplasia of the epididymides (a
congenital defect).
[0242] All rats treated with 0.075 mg/kg of AGN 194310 displayed
evidence of spermatogenic arrest after 2 and 4 weeks of treatment.
No increase of round spermatidis were seen in the epididymal caput
and cauda of these animals. The weight of the testes and
epididymides of the treated animals was significantly reduced after
4 weeks of treatment, and this weight decrease persisted to some
degree in rats sacrificed after 18 weeks of recovery. Histological
analysis revealed that active spermatogenesis had resumed in the
treated animals, but no mature sperm were seen in the
epididymides.
[0243] After 23 weeks of recovery, 2 of the 3 rats had completely
recovered with normal testes weights, a complete spermatogenesis
cycle, and mature sperm in the epididymides. The remaining animals
had complete spermatogenesis in the left testis, incomplete
spermatogenesis in the right testis, and mature sperm in both
epididymides. Interestingly, the seminal vesicles, of all the
treated animals were normal; seminal vesicle weight is dependent on
serum testosterone. These data suggest that serum testosterone
function remains normal during treatment with AGN 194310. All
tested animals were fertile after 23 weeks of recovery and able to
reproduce healthy pups.
[0244] Among the animals treated with 0.150 mg/kg AGN 194310
similar results were seen. Spermatogenic arrest was observed in all
rats treated after 2 and 4 weeks of treatment. After 23 weeks of
recovery, 4 out of 6 rats appeared to have completely recovered,
with active and complete spermatogenesis seen, and normal testes
weight. These 4 rats were able to reproduce normally. The remaining
two animals had incomplete spermatogenesis no mature sperm seen in
the epididymides histologically.
[0245] These results indicate that the effects of the drug are
fully reversible when administration of AGN 194310 is halted.
Additionally, the results are expected to be substantially similar
whether the drug is applied orally or topically.
EXAMPLE 4
Topical Administration of AGN 193109
[0246] This experiment is conducted as indicated in Example 2,
except that the drug is 193109 rather than AGN 194310, and a
Recovery group is monitored for a period of time post-treatment as
in Example 3. Dosages of the '109 drug is the same as for the
topical treatment with the '310 drug.
[0247] The results are substantially similar to those reported in
Example 3 for AGN 194310. At the effective dose, spermatogenic
arrest can be seen within thirty days after initiation of treatment
by examination of the testes of the treated animals. A histological
analysis of the testes reveals the absence of primary
spermatocytes, spermatids and spermatozoa in the majority of
animals' seminiferous tubules. These effects are reversible; a
similar analysis conducted on the testes of males rats 12 weeks
after administration demonstrates the repopulation of the tubules
with males gametes in various stages of development.
[0248] In a preliminary test using a small population (5) male
cynomologus monkeys, treatment with AGN 194310 at a daily dosage of
1.25 mg/kg did not result in inhibition or arrest of
spermatogenesis. Those of skill in the art will recognize that
these are initial results. Assuming arguendo these results are
reproducible the results could be due to many factors, including,
without limitation, suboptimal dosage, delivery vehicles or modes
of treatment that are differentially effective in cynomologus
monkeys and rats, or the possibility that AGN 194310 has different
effects in monkeys as compared to rats. Those of skill in the art
will also recognize that both rats and monkeys are commonly used
and accepted animal models for drug efficacy in humans.
[0249] In light of the disclosure of this patent specification, the
person of ordinary skill in the art would expect that treatment of
a male human with an effective dosage of a RAR antagonist or
inverse agonist able to inhibit spermatogenesis in male non-human
mammals such as rats and/or monkeys, would have similar effects in
humans, both in terms of spermatogenic arrest as well as
reversibility. Depending upon the Kd of the antagonist or inverse
agonist, such drugs may have to be given at dosage levels, or
frequencies, other than those described above. By "Kd" is meant the
binding constant; defined as that concentration of the drug at
which 50% of the drug is bound to an RAR receptor. Additionally,
the Applicants intend to make no statement herein that should be
construed as a representation that the dosage levels and dosage
frequencies mentioned herein are necessarily optimal.
[0250] It will be recognized by the person of ordinary skill in the
art that the ability or failure of a given drug to stimulate a
specific response, such as spermatogenic arrest, in one species or
genus of male mammal is not necessarily indicative of the ability
or failure of the same drug to stimulate the same response in
another species or genus of mammals.
[0251] The invention is not to be seen as limited by the foregoing
examples, which merely set forth certain preferred embodiments of
the invention. Other embodiments can be found in the claims that
conclude this specification.
* * * * *