East and Southern Africa Region (ESAR) houses the largest number of people living with HIV, with women being worst affected.
According to Avert, a United Kingdom-based charity that has been providing accurate and trusted information about HIV and sexual health worldwide for over 30 years, in 2018, HIV prevalence among young women (15-24 years) in the region was more than double that of young men (1,6 million young women living with HIV, compared to 660 000 young men), and in some countries the disparity between genders is even greater.
News that broke on Monday has provided renewed hope for women in Zimbabwe and ESAR.
A study HPTN 084, led by the HIV Prevention Trials Network (HPTN), found a pre-exposure prophylaxis (PrEP) regimen of long-acting cabotegravir (CAB LA) injections once every eight weeks was safe and superior to daily oral tenofovir/emtricitabine (FTC/TDF) for HIV prevention among cisgender women in sub-Saharan Africa.
Developed by ViiV Healthcare, cabotegravir proved 89 percent more effective than the standard oral pre exposure prophylaxis tenofovir/emtricitabine combination pills widely used for HIV prevention.
If approved, it is potentially a better method for those who may have challenges with adhering to daily pill treatment long-term.
A long-acting PrEP product could also offer a better choice for women at substantial HIV risk who either do not want to take or struggle with taking a daily tablet.
The HPTN 084 enrolled 3 223 women aged 18-45 years old who were at risk for acquiring HIV infection in 20 sites across seven countries in sub-Saharan Africa.
These are Botswana, Kenya, Malawi, South Africa, eSwatini, Uganda and Zimbabwe.
Taking into consideration the safety and efficacy on the long-acting injectable antiretroviral drug cabotegravir (CAB LA), the trial Data and Safety Monitoring Board (DSMB) stopped the study early as results showed CAB LA to be highly effective in preventing HIV acquisition.
The study was originally designed to continue through to 2022.
A total of 38 HIV infections occurred during follow-up, with four infections in the CAB LA arm (incidence rate 0.21 percent) and 34 infections in the FTC/TDF arm (incidence rate 1.79 percent). The hazard ratio in the CAB LA versus FTC/TDF arm was 0.11 (95 percent CI 0.04-0.32).
Approximately nine times more incident HIV infections occurred in the FTC/TDF arm than in the CAB arm.
“These results meet the statistical criteria for superiority of CAB LA compared to FTC/TDF in the HPTN 084 study population. The higher-than-expected level of adherence to FTC/TDF throughout the study and overall low incidence rate in both arms of the study clearly demonstrate both drugs were highly effective at preventing HIV acquisition,” the study revealed.
Implications of the results
According to HPTN, women in the countries where the trial was conducted and across East and southern Africa continue to experience high HIV incidence. More effective and acceptable HIV prevention choices for women are needed.
While oral PrEP is highly effective in preventing HIV in women when taken as prescribed, some women find it difficult to take a daily tablet, and inconsistent use of oral PrEP reduces the prevention effect.
A long-acting injectable formulation has the potential to improve the prevention effect without relying on adherence to a daily oral PrEP regimen, and to increase prevention choices and acceptability among women.
“These results do not contradict evidence showing that consistently using oral PrEP is highly effective as has been demonstrated in several trials.
“However, adhering to the daily dosing schedule is important. Even short lapses in taking oral PrEP can reduce the protection from HIV acquisition,” HPTN findings said.
Responding to HPTN 084 interim results, Chairperson of the Zimbabwe Women Living with HIV National Forum Catherine Murombedzi said: “It’s exciting, the pill burden compounded with ageing for us the over 50s is over, the injectable is a milestone.”
She said for the young people too, this means no more worries of carrying medication everywhere.
“It also melts away stigma, no more going out to a private space to take medication for many who found public disclosure restrictive.
“It is everyone’s right to privacy and the injectable has just weighed in superbly. I feel the joy in the HIV sector, it feels as if a weight has been taken off, unyoked,” added Murombedzi.
“I am looking forward to this freedom jab. No more defaulting for those who missed a dose, viral suppression is now a tangible reality.”
According to Murombedzi, 2020 has been a great year, making strides towards ending AIDS.
“In July it was the dapivirine ring, locking out the HIV virus as a prevention tool to achieve zero new HIV infections. Now, another ace in HIV prevention through adherence from the injectable to last a whole two months.
“Thanks to science, prevention remains the cornerstone to winning the battle,” added Murombedzi.
She said the jab lessens the pill burden for people with other chronic conditions like diabetes and hypertension.
“For discordant couples, this is sweet music, it will result in viral load suppression, undetectable is equal to untransmutable U=U,” she added.
HIV Research for Prevention (HIVR4P) Virtual Co-Chair Linda Gail Bekker said: “In sub-Saharan Africa, women bear a disproportionate burden of the HIV epidemic. Long-acting injectable forms of PrEP give them more choice and more control over their lives.”
“The results from HPTN 084 are incredibly important for women in Africa where lowering HIV incidence remains a priority,” Dr Sinead Delany-Moretlwe, HPTN 084 protocol chair, director of research at Wits Reproductive Health and HIV Institute, and research professor at the University of the Witwatersrand in Johannesburg, South Africa told FHI 360.
“We know that adherence to a daily pill continues to be challenging, and an effective injectable product such as long-acting CAB is a very important additional HIV prevention option for them.
“We are grateful to the women who volunteered for this study and the research staff, as this study would not have been possible without their commitment to HIV prevention.”
The study investigators will provide more detailed information about the study findings, including more comprehensive data, as soon as is feasible.
The HPTN 084 study is jointly-funded through a unique partnership between NIAID, the Bill & Melinda Gates Foundation, and ViiV Healthcare. Study drugs are provided by ViiV Healthcare and Gilead Sciences, Inc.