HIV-positive people who took injectable cabotegravir + rilpivirine every four or eight weeks as antiretroviral therapy found it more convenient and discreet than daily pills, also feeling that it eliminated a “daily reminder of living with HIV”, Deanna Kerrigan and colleagues report in PLOS One.
Similarly, HIV-negative men who took injectable cabotegravir every 12 weeks as pre-exposure prophylaxis (PrEP) felt that it was probably more convenient and easier to adhere to than daily pills, according to a study from the same research team published in AIDS & Behavior.
Healthcare providers were also supportive, but did point out that the clinical management of long-acting injectable antiretrovirals (ARVs) is more complex. They noted that injectables will not necessarily eliminate the challenge of adherence, with regular attendance at clinic visits more crucial than ever.
Both studies involved in-depth interviews with subsets of people who had taken part in phase II clinical trials, as well as with healthcare providers at trial sites.
The LATTE-2 trial provided cabotegravir + rilpivirine to HIV-positive people who had not previously taken HIV treatment before, in the United States and Spain. Injections occurred every four or eight weeks, depending on which study arm a person was randomised to. For the follow-up qualitative study, 27 study participants and 12 healthcare providers were interviewed.
The ÉCLAIR trial provided cabotegravir to HIV-negative men, as PrEP, in the United States. Participants had injections every 12 weeks, although it has since become clear that an eight-week schedule is more likely to be effective. For the qualitative study, 26 participants and four healthcare providers were interviewed.
In both studies, most but not all of the trial participants interviewed were gay men in their thirties. As people who had volunteered to take part in these studies, they may be more motivated and enthusiastic about injections than other people who need ARVs. Also whereas by definition the HIV-positive participants all needed HIV treatment, most of the HIV-negative participants did not feel that they were at high enough risk to need to take PrEP for themselves.
Most trial participants had had some side-effects from the injections, typically soreness and minor bruising at the injection site for a day or two. A minority had more severe reactions such as fever or impaired mobility. Nonetheless, most felt that the side-effects were “worth it”, as this man taking cabotegravir + rilpivirine for HIV treatment explained:
“One day is nothing… It’s as if you have a day with a headache. You take ibuprofen and that’s it. You put up with it. It’s temporary.”
Injections were felt to be more convenient and easier to adhere to than daily pills by both sets of participants. Especially among those living with HIV, injections were felt to be more private, as other people would not inadvertently see their medication.
“It seems to me that it’s much better because you simply don’t have to worry about anything. If you go on a trip, you don’t have to bring your pills or take anything at all along. You follow your ‘normal life.’ You come once a month. You get the shot and it’s over. You don’t have to be thinking everyday… oh I forgot to take the pill. Or… when did I take it last… You just don’t worry about anything. In reality, taking the pill everyday keeps it [HIV] present… and the shot is just once a month… You remember it when you come in and the rest of the time you can basically forget it.”
Nonetheless, a few participants did express concern about the number of clinic visits required. Friends, family and work colleagues could ask why the person needed to see the doctor so often, potentially leading to unwanted disclosure of HIV status.
Participants agreed that the intramuscular injections (in the buttocks) needed to be provided by a skilled professional, such as a doctor or nurse. A number of possible clinical settings were suggested for providing the injections, but self-injection was not felt to be realistic.
Gay men taking part in the PrEP trial often felt that the injection could give ‘peace of mind’, especially given unanticipated risks.
“I’m thinking why not do injectable PrEP because there could be that one night where you’re not even planning for that, you’re like, oh wait, I have to take pills for a week before I even consider doing this. Because for men who have sex with men, being spontaneous is there. The hookup culture is so prevalent.”
When asked who are the ‘right people’ to use injectables – rather than daily pills – respondents often referred to people who find adherence challenging. Mention was made of people with unstable lives, homeless individuals, substance users and younger people. Potential users must also not have an aversion to needles.
But most of the people living with HIV said that they would recommend injectables to ‘anyone’ living with HIV. Several said that their friends were jealous when they learned of how they were taking their medication.
“90% of the people will prefer this method.”
However, the healthcare providers who were interviewed suggested that injections may not be right for everyone, with the choice of medication best decided on a case by case basis. While people who are less likely to adhere to daily pills might theoretically be good candidates for injectables, they noted that people still need to show up for appointments.
“My concern with injections is this: when you have someone who's just not compliant. If they're not compliant and they miss two or three oral doses, it's not the end of the world. If you're not compliant with every eight weeks, that could be an issue. So you've got to get people who understand the importance of adhering.”
One older man living with HIV noted that as he needed to take several other oral medications in addition to his HIV treatment, he was happy to stick with the pills.
Clinicians also noted that the clinical management of injectables was more complex than with daily pills. Patients need to begin with oral drugs, then switch to injectables, a process which needs to be actively managed. Injectables cannot be discontinued quickly in the event of adverse reaction. Moreover, cabotegravir persists in the body for a long time after discontinuation, potentially creating problems in relation to drug resistance.
To conclude, both injectable HIV treatment and injectable PrEP were highly acceptable and feasible for study participants, with the potential to allow for better adherence.