Malawi sex ring study to curb HIV
After successfully completing a study on a malarial vaccine, medical researchers in Malawi will by the end of the year be releasing results of another clinical trial to establish the safety and effectiveness of microbicides in the prevention of the transmission of HIV and AIDS in the country.
The study being conducted by the University of North of Carolina (UNC) in the capital city, Lilongwe and John Hopkins University in Blantyre city, is working at producing reliable evidence ascertaining the possibility of preventing HIV infection through applying microbicides to the surface of the vagina or rectum in order to prevent the virus being passed on during sex.
The two sites mainly conduct research in vaginal microbicides and Pre exposure prophylaxis studies for the prevention of sexual transmission of HIV among other studies.
Tchangani Tembo, UNC Microbicide Study Coordinator, said the research was initiated in response to observations that unprotected sexual intercourse is the number one mode of HIV transmission among women.
“Women are at high risk because of biological factors that make them more vulnerable. To add to this, condoms have been noted to be an inadequate prevention option for women as many women are unable to negotiate condom use with their partners,” he said explaining; “The introduction of microbicides would not require a partner’s cooperation, they would put the power to protect into women’s hands.”
Targeting consenting, sexually active, non-pregnant, HIV uninfected women aged between 18 – 45, the study on the efficacy of the vaginal matrix ring containing 25mg Dapivirine aims to explore and determine the effectiveness of preventing HIV-1 infection in women and to assess the safety of the dapivirine vaginal ring over the investigational product use period.
Dingaan Mithi, Programmes Manager at The Journalists Against AIDS (JournAIDS) explained that the ring is designed to deliver sustained-release of an ARV which would decrease the ability of a virus to be transmitted.
Mithi said the ring trials were launched in 2012 by IPM, ASPIRE, and the US National Institute of Health-funded Microbicide Trials Network.
He noted that the spread of HIV/AIDS continues to outpace the world’s response to the disease and in its wake left every three people starting treatment in 2010 with five people becoming newly infected.
“Unfortunately, women and girls continue to bear the burden of the epidemic, especially in sub- Saharan Africa where approximately 6 in 10 HIV-infected adults are women,” he said adding that current prevention strategies were not enough to stop the spread of HIV particularly among women.
“Abstinence is also not realistic for women who are married, who want children or who are at risk of violence,” the JournAIDS Manger said.
The Malawi trial, currently at a multi-centred, randomized, double-blind, placebo-controlled Phase III is expected to bring out its final findings after successfully enrolling 142 trial participants in Lilongwe and 130 in Blantyre.
In other countries, the total number of participants is 2 629 across the sites.
Microbicides are designed to destroy microbes (bacteria and viruses) or to reduce their ability to establish an infection. As rings, gel, cream or suppositories, they can be used to stop the virus from entering human cells, kill or inactivate HIV, enhance the body’s normal defence mechanisms against HIV or inhibit HIV replication.
Currently, no microbicide for HIV exists outside of clinical trials.
The active ingredients in microbicides are based on the same types of ARV drugs used to prolong the lives of HIV-positive individuals and to prevent mother-to-child transmission of the virus.
Microbicides trials undergo three phases before being judged effective and safe.
Phase I involves a small number of volunteers to test the safety of various doses.
Phase II involves hundreds of volunteers to further assess safety and, in some cases, positive responses while Phase III involves thousands of volunteers to test safety and effectiveness.
“But even if the microbicide trials were successful in HIV prevention, it would still take some time before it became available in the country because the product would also have to undergo review and licensing by regulatory agencies before becoming available to the public.
It would require working out the best formulation and dosage,” observed Tembo.
The use of microbicides would create some light towards the discovery of an HIV and AIDS vaccine.
Experts have also argued that in order to ensure microbicides were available to women in low- and middle-income countries like Malawi, profit margins would need to be brought down by pharmaceuticals.
The Malawi UNC Study Coordinator said decades of research into microbicides have proven ARV-based microbicides can offer women protection against HIV infection and potentially save millions of lives.
Tembo explained that In 2010, successful results of the CAPRISA 004 trials in South Africa to assess the safety and effectiveness of tenofovir gel in 900 HIV-negative, sexually active women between the ages of 18 and 40 years, were announced.
“The study reported that tenofovir gel reduced the risk of HIV infection by 39 percent overall and the protective effect increased to 54 percent among women with high gel adherence,” he said adding; “The CAPRISA 004 study which statistically showed that microbicides can prevent the sexual transmission of HIV, was the first to provide proof of concept for microbicides.
“The development of safe and effective HIV prevention technologies that can be made easily accessible to developing countries remains a public health priority, Tembo said.
The anti-HIV transmission vaginal microbicides, antiretroviral (ARV) based products, touted as a “women-initiated HIV infection reduction method” are being developed to assist women who find it difficult or undesirable to correctly and consistently use condoms.
However, Tembo hinted that challenges hindering progress of the trial include lack of adherence to the microbicides, unwillingness of husbands to allow spouses to participate in trials as well as inadequate information of the principles of research for community understanding.
A study of microbicide acceptability ancillary to a microbicide clinical trial in Malawi and Zimbabwe showed that though acceptability of microbicides was found to be high, sexual intercourse is accompanied by issues of power and gender norms that place women, particularly those in stable union, at a disadvantage for enactment of risk reduction strategies.
The study noted that though the success of microbicides hinged on women ability to initiate use, the need for men’s cooperation or agreement needed to be carefully considered.</p>
Another report on a follow up to an empirical study conducted in Malawi to assess trial participants’ understanding of 3 scientific concepts (randomisation, double-blinding and placebo use) and their personal implications suggested that studies can better be understood by low literacy populations using simple language and everyday local examples for the participants to positively understand trial procedures
The report noted that research participants failed to differentiate between research and routine care because of inadequate information.
“Trial concepts of randomization, double blinding and placebo are difficult to explain to study participants since they are part of the scientific language that low literacy populations are not familiar with,” said the report.
It added that: “Limited understanding of trial procedures suggests that what is often termed informed consent may not be adequately informed and goes against the principle of respect for persons which requires that individuals understand the information they are provided with before making decisions on participating in a trial.”
Journalists Association Against AIDS (JournAIDS) in Malawi is collaborating with the International Partnership for Microbicides (IPM) in raising awareness on the need to promote microbicides as an important HIV prevention technology especially towards women.
Microbicides have in recent times gained both status and funding as a way for women to protect themselves against HIV infection in situations where they have little negotiating power to persuade male partners to use condoms.