Tuesday, 13 May 2014 14:17

Reports indicate failed HIV trials had inaccurate adherence measures

Written by Laura Owning

A new analysis of an HIV prevention trial previously known to have poor outcomes has now revealed that

behavioural measures used for assessing adherence were inaccurate.

 

 

The Vaginal and Oral Interventions to Control the Epidemic (VOICE) trial assessed the effect of taking oral

tenofovir tablets, oral Truvada tablets or vaginal tenofovir gel antiretroviral medicines in preventing HIV.

The study involved 5,029 women in South Africa, Uganda and Zimbabwe from 2009 to 2012. Adherence rates

were determined based on self-reporting from participants and counts of unused applicators and pills.

The first result of the trial, which was presented last year, showed that none of the three medicines was

effective.

But the results of a new analysis based on blood samples, presented at the 21st Conference on Retroviruses and

Opportunistic Infections recently in Boston in the United States gives insight into the challenges of self-reporting

and treatment mechanisms for the sub-Saharan Africa population.

Analysis

The new analysis reveals that despite a 90 percent adherence rate reported by the women; only 25 percent

actually used the products.

“What we presented was an in-depth analysis of that divergence between behaviour and biological measure of

endurance based on drug detection in biological specimens,” says Ariane van der Straten, VOICE lead

researcher and a senior research scientist at the US-based RTI International.

Van der Straten attributes the poor adherence rates to factors that include the burden of taking a daily treatment

product and safety concerns among the women.

“There was concern about taking ARV drugs as prevention as they are conceived as treatment drugs. So, there was a worry of being ‘pegged’ as HIV positive,” she says.

According to Van der Straten two social and behavioural sub-studies, VOICE C and VOICE D, will explore the

reason high-risk women did not follow the study process. Results are expected later this year.

The current VOICE analysis, however, is already making an impact in the HIV research community, says

Deborah Baron, programme manager at South Africa’s Wits Reproductive Health.

“When those of us in the field initially heard the 2013 results, we were surprised and were discouraged.

However, we have learned a lot from the study,” Baron says.

The adherence protocol was enhanced with real-time batch testing.

“This is a tool researchers could use to intervene in real time, rather than at the end of a study, as we saw in

VOICE,” explains Baron. She adds: “But it must be done carefully to ensure you do not unblind the study.”

The new study sheds light on the mechanism for treatment of patients with HIV in Africa.

“Women do not want interventions that will require that they use them daily, but may prefer those to be taken

weekly,” says Gita Ramjee, director of the South African Medical Research Council’s HIV prevention programme.

The council is currently involved in two studies testing the efficacy of a vaginal ring that contains an antiretroviral

agent and is inserted for 30 days. Results are expected in late 2015.


 

 

 

Courtesy of SciDev.Net’s Sub-Saharan Africa desk

This article was also published in the Kenyan Woman Issue 46

Sign up

AWC maintains a constant flow of well-researched feature stories and publications

Read → Feature articles | Commentary Service | Newspapers | Reports | Books


Fill in your email address to get highlights from our publications

Publications

  • 1