By Dickens Wasonga.
A large HIV prevention study involving over 3000 women in Kenya and three other African other has suffered a huge set back after it was ordered stopped by an independent body which review trial data to ensure that participants are not being adversely affected by a daily dose of the study pill.
The revelation that has surprised the scientists involved in the trials was taken by the Independent Data Monitoring Committee which directed the researchers to bring to an early closure, the clinical trials of Truvada, an ARV which was under investigation to see whether it could be given to prevent HIV infections on HIV negative women who are at higher risk of getting virus.
scientists showing journalists around the clinical trial site offices in Bondo
According to the scientists, the trials had to end prematurely after preliminary review indicated the study pill was unlikely to prevent HIV infections amongst women as earlier expected even though huge amounts of money could have gone to waste.
The Female pre-exposure prophylaxis study whose preparation began in 2007 in Bondo district, the only study site in Kenya was scheduled to end in June next year and was designed to study whether HIV negative women of between the ages of 18 to 35 and at the higher risk of infection by the virus could safely use a daily dose of the pill called Truvada to prevent infection.
The study was underway in two other African countries namely Tanzania and South Africa. In Harare Zimbabwe, a site was to be established in collaboration with the University of Zimbabwe and it was scheduled to begin FEM-PrEP trials in mid 2011 but the site could not be initiated due to the premature closure and no participant was enrolled.
But the trials were on going in Bondo and Rarieda of Nyanza province where screening for the would be eligible participants started in 2009. A total of 1495 women in the targeted group were screened and 739 of them were enrolled into the clinical trial that had initially given hope to the researchers involved.
Out of the number that was screened 992 failed the tests and were excluded from the study. By the end of last month, 331 women enrolled had been in the study taking the trial pills for one year.
The study whose fate now appears to hang in the balance at least until the committee that monitors similar trials all over the world gives its verdict was being implemented by the Family Health Internationla in partnership with the Impact Research and Development Organization and other research centers in Africa and had intended to enroll 3900 women in all the study sites in the four African nations when completed..
It was being funded by the United States Agency for International Development [USAID], with early funding from the Bill and Melinda Gates Foundation and if it proceeded to its logical conclusion , the Kenyan site alone would have gobbled an estimated 4 million US dollars.
So what went wrong?
Dr. Kawango Agot, the director of Impact-RDO and FEM-PrEP site investigator for the Bondo study area said this preliminary result from the study does not eliminate Truvada as a potential HIV prevention method for women.” what we can say is that, at this time, it cannot be determined whether this drug works to prevent HIV infection in women in the FEM-PrEP trial.Other ongoing HIV prevention studies may be able to shed further light on the effectiveness of Truvada among women” she said.
HIV scientists in Kenya and other countries were surprised and disappointed by the interim results, especially because another recent study called iPrEx, found that the same drug, Truvada, could prevent HIV infections among men who have sex men at risk of the virus.
According to the Kenyan team, the reason for the surprising findings among women in the FEM-PrEP study is not clear at this time. They believe it could be the women who were on the study were not taking the study pill consistently very day and that the drug works differently in men and women.
The scientists have not yet finished analyzing all the FEM-PrEP data and they are currently investigating a number of possibilities. But Dr. Agot said the study will now be closed over the next few months as study participants complete their final study visits to the Bondo clinic. She said the preliminary results have already been shared with most of the participants ,the local communities are also being informed at this i moment . ”Once the final results are known, they will be shared with everyone” She added.
Is it possible then that the participants may have failed to adhere to the drug?
According to the researchers, socio behavioral information plays an important complementary role in HIV prevention clinical trials. The behavior of the participants , such as their regular attendance at the scheduled clinic visits and their adherence to the study pill is fundamental to success of clinical trials.
As part of FEM-PrEP, the study team said they developed and monitored procedures for reaching women who were at higher risk , implemented strategies to promote adherence to the study pill, examined aspects of clinical trial that were difficult for participants to understand and promoted community engagement in research. Data were also gathered on adherence to the study pill and on participants sexual behaviors while taking the study pill.
So who did not do what and why ?
Documents relating to the study confirms that during trial implementation , the study teams monitored and provided on going feedback about recruitment strategies, comprehension of the informed consent process, and counseling to improve adherence to the study pill, risk reduction and contraceptive counseling , as well as community education and outreach.
Data was also gathered to understand general issues of adherence and sexual behavior in the context of the clinical trial and they systematically engaged community stakeholders in the research process.
The claim therefore that participants failure to adhere to the drug stand very slim chances of raising a debate amongst observers. This is because in their own findings, 90 per cent of the participants in all the study sites in the participating countries made a come back for the follow up visits every month and were retained in the trials.
As at the 18th of February this year, preliminary findings indicated that 95 per cent of the study participants had adhere to the study product. 5 per cent of new HIV infections were noticed on participants although the scientists at the Bondo site had expected 4 per cent and 56 new infections occurred in all the sites.
The primary goal of the study in addition to assessing the effectiveness of Truvada in preventing HIV infection in women is to evaluate its safety when used daily by women who are not infected with the virus.
It is licensed as an HIV treatment by the drug regulatory agencies in a number of countries , including Kenya, Tanzania, South Africa, Zimbabwe and the United States. It has shown to be safe if taken by HIV positive people for the treatment of HIV.
Because the drug had not been assessed as a drug to prevent HIV, a primary goal of PrEP clinical trial is to evaluate its safety amongst its HIV negative people. The iPrEx clinical trial, which released its results in November 2010, found no substantial safety concerns when Truvada was taken by men who have sex with men to prevent HIV.
But following a scheduled interim review of the FEM-PrEP study data, the Independent Data monitoring Committee advised that the study will be highly unlikely to be able to demonstrate the drug’s effectiveness in preventing the HIV in the study population even if it continued to its originally planned conclusion.
And with that verdict of the committee the entire team in the trials were thrown into abrupt halt of the project that has gobbled millions of shillings from the sponsoring organizations.
ENDS.