FDA approves first injectable treatment for HIV pre-exposure prevention

The US Food and Drug Administration (FDA) has approved Apretude (cabotegravir extended-release injectable suspension) for use in at-risk adults and adolescents weighing at least 35 kilograms (77 pounds) for pre-exposure prophylaxis (PrEP) to reduce the risk of sexually-acquired HIV. Apretude is given first as two initiation injections administered one month apart, and then every two months thereafter. Patients can either start their treatment with Apretude or take oral cabotegravir (Vocabria) for four weeks to assess how well they tolerate the drug, FDA said in a statement yesterday.

This approval adds an important tool in the effort to end the HIV epidemic by providing the first option to prevent HIV that does not involve taking a daily pill, said Debra Birnkrant, MD, Director, Division of Antivirals, Center for Drug Evaluation and Research, FDA.

Birnkrant also added, “This injection, given every two months, will be critical to address the HIV epidemic in the US, including helping high-risk individuals and certain groups where adherence to daily medication has been a major challenge or not a realistic option.”

The statement further said that the safety and efficacy of Apretude to reduce the risk of acquiring HIV were evaluated in two randomised, double-blind trials that compared Apretude to Truvada, a once-daily oral medication for HIV PrEP. Trial-I included HIV-uninfected men and transgender women who have sex with men and have high-risk behaviour for HIV infection. Trial-II included uninfected cisgender women at risk of acquiring HIV.

Participants who took Apretude started the trial with cabotegravir (oral, 30 mg tablet) and a placebo daily for up to five weeks, followed by Apretude 600mg injection at months one and two, then every two months thereafter and a daily placebo tablet. Participants who took Truvada started the trial taking oral Truvada and placebo daily for up to five weeks, followed by oral Truvada daily and placebo intramuscular injection at months one and two and every two months thereafter, it added.

The statement said that in trial-I, 4,566 cisgender men and transgender women who have sex with men received either Apretude or Truvada. The trial measured the rate of HIV infections among trial participants taking daily cabotegravir followed by Apretude injections every two months compared to daily oral Truvada. The trial showed participants who took Apretude had 69 per cent less risk of getting infected with HIV when compared to participants who took Truvada.

It further mentioned that in trial-II, 3,224 cisgender women received either Apretude or Truvada. The trial measured the rate of HIV infections in participants who took oral cabotegravir and injections of Apretude compared to those who took Truvada orally. The trial showed participants who took Apretude had 90 per cent less risk of getting infected with HIV when compared to participants who took Truvada.

Side effects occurring more frequently in participants who received Apretude compared to participants who received Truvada in either trial include injection site reactions, headache, pyrexia (fever), fatigue, back pain, myalgia and rash, informed the statement.

The statement also warned that Apretude includes a boxed warning to not use the drug unless a negative HIV test is confirmed. It must only be prescribed to individuals confirmed to be HIV-negative immediately prior to starting the drug and before each injection to reduce the risk of developing drug resistance. Drug-resistant HIV variants have been identified in people with undiagnosed HIV when they use Apretude for HIV PrEeP. Individuals who become infected with HIV while receiving Apretude for PrEP must transition to a complete HIV treatment regimen. The drug labelling also includes warnings and precautions regarding hypersensitivity reactions, hepatotoxicity (liver damage) and depressive disorders.

Apretude was granted a Priority Review and Breakthrough Therapy designation. The FDA granted the approval of Apretude to Viiv, it said.

According to the US Centers for Disease Control and Prevention, notable gains have been made in increasing PrEP use for HIV prevention in the US and preliminary data show that in 2020, about 25 per cent of the 1.2 million people for whom PrEP is recommended were prescribed it, compared to only about three per cent in 2015. However, there remains significant room for improvement. PrEP requires high levels of adherence to be effective and certain high-risk individuals and groups, such as young men who have sex with men, are less likely to adhere to daily medication. Other interpersonal factors, such as substance-use disorders, depression, poverty and efforts to conceal medication also can impact adherence. It is hoped that the availability of a long-acting injectable PrEP option will increase PrEP uptake and adherence in these groups.