Development of a vaginal microbicidal contraceptive gel (UniPron) for the prevention of sexually transmitted infections and unwanted pregnancies

Abstract

Globally, unplanned pregnancies and sexually transmitted infections infections including HIV and AIDS are huge challenges to women’s reproductive health. Development of a femalecontrolled vaginal preparation that has microbicidal and contraceptive properties has the potential to have widespread impact. Such a dual protection method could prevent unwanted pregnancies and reduce the risk of acquisition and transmission sexually transmitted infections. ‘UniPron’ is a candidate vaginal product that is undergoing testing and its potential applications include use as a personal lubricant, a vaginal contraceptive and/or a microbicidal product. As a result of research carried out at the Institute of Primate Research, a premier biomedical World Health Organization collaborating centre in collaboration with a local Pharmaceutical Company-Universal Pharmaceutical Corporation Limited, UniPron was formulated, developed and patented (Patent No. KE 218) as vaginal microbicidal contraceptive gel. Uniron is an acidifying agent with highly buffered low pH that works by lowering the vaginal pH to enhance normal vaginal defence mechanism. It is formulated as a gel with concentrations of 0.4g, 0.8g and 1.2g of citric acid which is the active component. Also formulated and developed is a vaginal lubricating gel (Smuggle) the lubricant in Uniron. These products have since received three Awards namely, the National Council for Science and Technology, Kenya Public Service Innovation and African Union Innovation Awards. This study aimed at determining the safety of Smuggle and Uniron gels as vaginal products; effectiveness of Uniron as a microbicide against sexually transmitted infection pathogens in vitro and as a contraceptive using the baboon model (Papio anubis). The effect of Smugel was compared with KY Jelly, the commonly used commercial vaginal lubricant worldwide manufactured by the American company Johnson and Johnson.Vaginal pH, blood chemistry, vaginal flora and vaginal and cervical histology were evaluated at baseline and after administration of 15 ml of the study gels intravaginally twice a week for eight weeks. Microbicidal effectiveness of UniPron was assessed against Neisseria gonorrhoea, Gardnerella vaginalis, Haemophylus ducreyi, Candida albicans and Escheriachia coli. Contraceptive effectiveness of UniPron was assessed by determining the duration the low pH was maintained in the baboon vagina following its administration, its effect on baboon sperm parameters in vitro and by time mating sexually active female baboons with males of proven fertility after intravaginal administration of the product. Repeated application of Smugel or UniPron into the baboon vagina did not cause any detectable changes in the safety profiles investigated. In addition, UniPron was found to be effective as a microbicide against N. gonnorhoea, G. vaginalis, H. ducryi, C. albicans, and E. coli in vitro and was effective as a nonhormonal vaginal contraceptive in the baboon model. Development of woman-controlled preventive methods that reduce the risk of sexually transmitted infections including HIV and unplanned pregnancies will not only improve human reproductive health which is a fundamental human right, but will also catalyse economic and social development for the realization of the Kenya government vision 2030 and the millennium development goals.