NEW DELHI: A vaginal gel can now protect women against HIV infection -- an innovation that scientists believe could be most crucial for reproductive health since the Pill.
On Tuesday, scientists announced at the International Aids Conference in Vienna that they have successfully tested a gel, containing antiretroviral drug Tenofovir, which is usually taken as a tablet by HIV patients. The drug can reduce a woman's chances of contracting HIV from an infected partner by 50% if used 12 hours before and after having sex.
Interestingly, the gel had undergone a safety and acceptability trial on 100 women at National Aids Research Institute (NARI) in Pune in 2007. It can also reduce the risk of genital herpes by 51%.
Being hailed as a major breakthrough globally, the CAPRISA trial followed 900 HIV-negative, sexually active South African women in the age group between 18 and 40.
Two-and-a-half-years on, researchers found the gel reduced chances of HIV infection by 50% after a year and 39% after 30 months. The study revealed that those women -- who used the drug consistently nearly 80% of the time before having sex -- would be 54% less prone to infection.
Health secretary K Sujatha Rao told TOI "This is a major breakthrough, and will especially benefit India's 300,000-strong sex worker community involved in multi-partner sex. It will also help women who usually do not have the power to insist on condom use and fidelity, or to abandon partnerships that put them at high risk."
K Chandramouli, director general of National Aids Control Organisation. added, "At present, India has 2.7 million HIV patients. We also record 1.7 lakh fresh cases of HIV every year, nearly 40% of which are women. Such a microbicide, once ready for implementation in our programme, will greatly benefit women."
According to NARI director Dr R S Paranjape, the gel underwent safety and acceptability study in India as well.
"The preparatory work for the CAPRISA trial was conducted here along with the Microbicide Trials Network. The overall safety profile of the gel was good and it was well accepted by women. Presently, it provides 40% protection. The scientific community will now look at increasing this percentage," he explained.
With a vaccine against HIV remaining elusive, scientists have for the past 20 years been looking for such an effective microbicide -- products such as gels, films, rings or creams that women could apply on their vagina to prevent HIV transmission.
Finally, the breakthrough has happened, thanks to the microbicide that contains 1% Tenofovir.
Tenofovir gel is an advanced second-generation HIV-specific microbicide that neither tries to kill the AIDS virus nor block it from entering the body as its predecessors. Instead, it is designed to prevent the virus from replicating when it comes in contact with an uninfected T-cell.
Naturally, the virus will fail to survive for long to cause systemic infection.
Women, who constitute 50% all new HIV cases globally, are also twice as likely as their male partners to contract HIV during unsafe sex. "Tenofovir gel could fill an important HIV prevention gap by empowering women who are unable to successfully negotiate mutual faithfulness or condom use with their male partners," said study co- principal investigator Dr Quarraisha Abdool Karim. "Eleven trials in the past 15 years have shown no change or even sometimes an increase in transmission rates. Tenofovir gel has a potential dual effect in preventing HIV. Since women with genital herpes are much more likely to become infected with HIV, the additional protection of tenofovir gel against herpes creates a second mechanism whereby the gel may have a bigger impact in preventing HIV," he explained.
The gel is undergoing another Microbicide Trials Networks VOICE -- Vaginal and Oral Interventions to Control the Epidemic -- study that will provide evidence about the safety and efficacy of tenofovir gel used daily, irrespective of when participants have sex.
Once this study is conducted, drug regulatory authorities will determine if the gel is safe and effective for HIV prevention. It may take another two years before public can use it.
Michel Sidibe, executive director of UNAIDS, said, "For the first time, we have seen results for a woman-initiated and controlled HIV prevention option." ( A times of India report)
Naturally, the virus will fail to survive for long to cause systemic infection.
Women, who constitute 50% all new HIV cases globally, are also twice as likely as their male partners to contract HIV during unsafe sex. "Tenofovir gel could fill an important HIV prevention gap by empowering women who are unable to successfully negotiate mutual faithfulness or condom use with their male partners," said study co- principal investigator Dr Quarraisha Abdool Karim. "Eleven trials in the past 15 years have shown no change or even sometimes an increase in transmission rates. Tenofovir gel has a potential dual effect in preventing HIV. Since women with genital herpes are much more likely to become infected with HIV, the additional protection of tenofovir gel against herpes creates a second mechanism whereby the gel may have a bigger impact in preventing HIV," he explained.
The gel is undergoing another Microbicide Trials Networks VOICE -- Vaginal and Oral Interventions to Control the Epidemic -- study that will provide evidence about the safety and efficacy of tenofovir gel used daily, irrespective of when participants have sex.
Once this study is conducted, drug regulatory authorities will determine if the gel is safe and effective for HIV prevention. It may take another two years before public can use it.
Michel Sidibe, executive director of UNAIDS, said, "For the first time, we have seen results for a woman-initiated and controlled HIV prevention option." ( A times of India report)
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