Gamendazole is a drug candidate for
male contraception
Male contraceptives, also known as male birth control, are methods of preventing pregnancy that solely involve the male physiology. The most common kinds of male contraception include condoms, outercourse, and vasectomy. In domestic animals, ca ...
. It is an
indazole
Indazole, also called isoindazole, is a heterocyclic aromatic organic compound. This bicyclic compound consists of the fusion of benzene and pyrazole.
Indazole is an amphoteric molecule which can be protonated to an indazolium cation or deproton ...
carboxylic acid
In organic chemistry, a carboxylic acid is an organic acid that contains a carboxyl group () attached to an R-group. The general formula of a carboxylic acid is or , with R referring to the alkyl, alkenyl, aryl, or other group. Carboxylic ...
derived from
lonidamine
Lonidamine is a derivative of indazole-3-carboxylic acid, which for a long time, has been known to inhibit aerobic glycolysis in cancer cells. It seems to enhance aerobic glycolysis in normal cells, but suppress glycolysis in cancer cells. This is ...
(LND). It has been shown to reduce fertility in male rats without affecting testosterone levels, but human clinical trials have not been started.
Rat studies
Gamendazole produced 100% antispermatogenic effects at 25 mg/kg
i.p. in rats, whereas 200 mg/kg was fatal for 60% of rats tested. Since gamendazole produced 100% efficacy, it was tested orally. At a dose of 6 mg/kg, 100% of rats were
infertile
Infertility is the inability of a person, animal or plant to reproduce by natural means. It is usually not the natural state of a healthy adult, except notably among certain eusocial species (mostly haplodiploid insects). It is the normal state ...
4 weeks after a single administration. Complete infertility was maintained for 2 weeks, followed by complete recovery in 4 of 7 rats. The other 3 never recovered fertility. Upon dosing 6 mg/kg orally for 7 days, it produced similar infertility results, but only 2 of 7 rats recovered fertility. There were no abnormalities in rates of
conception or abnormal conception in rats who recovered fertility.
Pathology
Pathology is the study of the causes and effects of disease or injury. The word ''pathology'' also refers to the study of disease in general, incorporating a wide range of biology research fields and medical practices. However, when used in ...
reports were conducted on gamendazole treated rats. At 25 mg/kg i.p., 6 mg/kg oral, and in animals that survived 200 mg/kg i.p., there were no remarkable findings, with no evidence of
inflammation
Inflammation (from la, wikt:en:inflammatio#Latin, inflammatio) is part of the complex biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or Irritation, irritants, and is a protective response involving im ...
,
necrosis
Necrosis () is a form of cell injury which results in the premature death of cells in living tissue by autolysis. Necrosis is caused by factors external to the cell or tissue, such as infection, or trauma which result in the unregulated dige ...
,
tumor
A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists ...
s, or
hemorrhage
Bleeding, hemorrhage, haemorrhage or blood loss, is blood escaping from the circulatory system from damaged blood vessels. Bleeding can occur internally, or externally either through a natural opening such as the mouth, nose, ear, urethra, vag ...
. There was also a lack of observable behavioral effects at 25 mg/kg i.p., 6 mg/kg oral, and in animals that survived 200 mg/kg i.p. Gamendazole treatment had no effect on
testosterone
Testosterone is the primary sex hormone and anabolic steroid in males. In humans, testosterone plays a key role in the development of Male reproductive system, male reproductive tissues such as testes and prostate, as well as promoting secondar ...
levels, and was reported to affect
Sertoli cell
Sertoli cells are a type of sustentacular "nurse" cell found in human testes which contribute to the process of spermatogenesis (the production of sperm) as a structural component of the seminiferous tubules. They are activated by follicle-stimul ...
function, leading to decreased levels of
inhibin B. Low levels of inhibin B were correlated to the infertility of the rat.
References
{{Reflist
Contraception for males
Experimental methods of birth control
Indazoles
Carboxylic acids
Trifluoromethyl compounds
Chlorobenzenes