Giant American drug companies Merck and Bristol-Myers Squibb, have signed agreements to develop a treatment called a microbicide, a gel or a cream that women can use to protect themselves from AIDS.
The companies have signed separate license agreements with the International Partnership for Microbicides (IPM) to develop the product, long sought by doctors and advocates as a way for women, as well as some men, to prevent infection.
Although many such compounds are in development, as yet, all are experimental.
This is the first time that a giant drug manufacturer has signed up to help produce one.
Dr. Peter Piot, Executive Director of the United Nations AIDS organization UNAIDS, says the search for an effective microbicide is crucial to providing women with more options to protect themselves against HIV infection.
Dr. Zeda Rosenberg, Chief Executive Officer of IPM, has said that worldwide, nearly half of all HIV infections are in women, and in some parts of Africa, the region by far the worst hit by AIDS, half of all people infected with the AIDS virus are women and young girls.
Rosenberg says that despite HIV prevention strategies including sexual abstinence and the use of male and female condoms, many women are infected by husbands or through forced sex, and few have the power to demand the use of a condom.
More than 39 million people, most of them in Africa, are infected with the human immunodeficiency virus that causes AIDS, and to date more than 25 million have died.
Although as yet there is no cure for the infection, a combination of drugs can help control the virus and keep people healthy, but only if they can access the drugs.
Doctors believe that a vaccine is the best way to control AIDS, which is mostly transmitted sexually but also through blood, shared needles and from mother to child during birth and while breast-feeding.
It may take decades for a vaccine to be developed, meanwhile prevention is the best way to fight AIDS.
Many groups such as IPM have been lobbying for the development of a microbicide, but funding has been limited.
Merck and Bristol are separately licensing to IPM, the rights to develop a new class of drugs called entry inhibitors, to try to develop into a microbicide.