Photo: International Aids Society President and International Co-Chair of AIDS 2022, Dr Adeeba Kamarulzaman
By Mike Mwaniki I mikemwaniki2016@gmail.com
Oral PrEP was first approved by the US Food and Drug Administration a decade ago, but uptake and adherence have been limited, partly because some people have difficulty taking daily pills.
In recent years, studies have shown that cabotegravir-LA (CAB-LA), administered by injection once every two months, is a safe and effective alternative to oral PrEP.
CAB-LA is approved for PrEP only in the US, but its maker, ViiV Healthcare, has submitted marketing applications in additional countries.
Speaking during the 24th International Aids Conference held in Montreal, Canada, the International Aids Society President and International Co-Chair of AIDS 2022, Dr Adeeba Kamarulzaman said, “Long-acting PrEP could play a major role in ending the HIV pandemic, but right now, very few people can get it.
“Scaling up affordable access to this game-changing prevention tool must be a top global priority.”
During the conference, researchers presented new data confirming that CAB-LA is safe and effective for PrEP in trans and cisgender women. The World Health Organisation (WHO) also released its first guidelines for CAB-LA for PrEP, and ViiV Healthcare and the Medicines Patent Pool announced that they have signed a voluntary licensing agreement for patents relating to CAB-LA for PrEP.
Finally, WHO, Unitaid, UNAIDS and The Global Fund announced the launch of a global coalition to accelerate access to long-acting PrEP with AVAC as the secretariat.
Researchers announced the first trans-specific analysis of data from the landmark HPTN 083 study confirming that CAB-LA is a safe and highly effective HIV prevention option for transgender women.
HPTN 083 is a Phase 3 study comparing CAB-LA to daily oral TDF/FTC for HIV prevention in cisgender men and trans women who have sex with men.
In 2020, researchers announced that HPTN 083 had demonstrated a 66 per cent reduced risk of HIV acquisition for CAB-LA compared to TDF/FTC.
The new analysis, which was presented at AIDS 2022 by Beatriz Grinsztejn of the Evandro Chagas National Institute of Infectious Diseases – Fiocruz (Brazil), reports on the safety, prevention efficacy and pharmacokinetics of CAB-LA in trans women during the blinded phase of HPTN 083.
Of 4,566 study participants, 570 (12.5 per cent) were trans women, 330 (57.9 per cent) of whom reported use of gender-affirming hormonal therapy.
HIV incidence among trans women was lower in the CAB-LA group (0.54 per cent) than in the TDF/FTC group (1.80 per cent).
CAB-LA was well tolerated in trans women and, importantly, initial findings suggest there is no impact of gender-affirming hormonal therapy on CAB concentrations
New data from the HPTN 084 study shows that among individuals assigned female at birth, CAB-LA continues to be superior to daily oral TDF/FTC in preventing HIV infection.
HPTN 084 is an ongoing Phase 3 randomised controlled trial of CAB-LA for PrEP in individuals assigned female at birth.
In late 2020, a planned interim review found that CAB-LA was superior to daily oral TDF/FTC for HIV prevention in this population.
The blinded portion of the trial was then stopped; participants were subsequently unblinded and continued on their original randomised study regimen pending a protocol amendment to offer open-label CAB-LA.
This update, which was presented at AIDS 2022 by Sinead Delany-Moretiwe of the University of the Witwatersrand (South Africa), reports that 23 incident infections (3 CAB-LA, 20 TDF/FTC) were detected in the 12-month unblinded period.
Of these, two (1 CAB-LA, 1 TDF/FTC) occurred during the blinded phase, and only one of the CAB-LA cases had ever received an injection.