Kenya has become a global centre for the testing of new medical compounds that block HIV transmission in women.
More than five studies are either being planned or going on in the country.
Human trials of various products - microbicides - are going on in Kisumu, Nairobi and Mombasa. Some of the candidates have been found to be safe for use in studies done in other countries.
A microbicide is a substance that can be incorporated in a lubricant, gel or barrier such as a diaphragm that will stop HIV transmission during sex.
According to the International Partnership for Microbicides chief executive officer, Dr Zeda Rosenberg, there is a new impetus to find new weapons in the fight against HIV following recent disappointments in the search for either a vaccine or a microbicide.
In an interview in Nairobi at the weekend, Dr Rosenberg said the new urgency is because of the development of a new generation of very effective antiretroviral drugs that can also be used as microbicide gels.
The new drugs, already in use by infected people or to prevent mother-to-child transmission, include Tenofovir Truvada and Dapivirine.
Studies on Tenofovir, which is used before having sex to curb HIV transmission, are also going on in Kenya. HIV-negative people take anti-HIV drugs before sex to prevent transmission.
Several strategies are being studied on microbicide delivery, including a daily dose of the gel. A more innovative way is a vaginal ring that releases the microbicide slowly for as long as a month.
“This would be a powerful protection tool for women who may not be able to discuss and reach a decision on safe sex with their partners,” said Dr Rosenberg.