Long-Acting Injectable HIV Treatment Moves Closer to Reality
Long-acting injectable treatment takes another step closer to becoming a real-world option for people living with HIV. The latest 96-week data from the LATTE-2 study, which is investigating long-acting injectable maintenance therapy for people with HIV, were presented at the 2017 International Conference on HIV Science, in Paris.
While viral suppression rates were very high, another notable finding was how much participants appreciated not having to take pills every day -- another sign that long-acting treatment could translate well to the real world and become the future of medication adherence.
What Is Maintenance Therapy?
"Maintenance therapy" is the concept that, after people with HIV achieve and sustain an undetectable viral load through current conventional means (a treatment regimen of at least one pill once a day, containing three or four drugs) for an extended period, they can switch to a regimen containing fewer drugs (either one or two). The idea is that they can take fewer drugs, thereby being exposed to less toxicity while still maintaining an undetectable viral load.
This is not yet a standard practice in real-world settings, but it could eventually mean that, instead of taking a pill containing three or four drugs every day, you take a pill containing only two. However, the LATTE-2 study takes this idea even further and proposes that, instead of taking a pill every day, people could receive an injection of long-acting drugs lasting up to four or eight weeks.
LATTE-2 Study Background
Since the study started a couple of years ago, the results have continued to be very promising (particularly last year's 48-week data), and the current 96-week data are equally positive.
The study began with an "induction phase," during which all participants were put on a daily oral treatment regimen containing cabotegravir and Epzicom (Abacavir/3TC, Kivexa). After 20 weeks, those who achieved an undetectable viral load (286 participants) were then randomized to receive one of three options:
- A long-acting injectable regimen containing cabotegravir + Edurant (rilpivirine) every four weeks (the Q4W group).
- A long-acting injectable regimen containing cabotegravir + Edurant every eight weeks (the Q8W group).
- The previous daily oral regimen of cabotegravir and Epzicom (the control group).
LATTE-2 Study Results
After 96 weeks, 94% of those in the Q8W group maintained an undetectable viral load, compared with 87% in the Q4W group and 84% in the oral control group.
"Serious adverse events," meaning occurrences that are considered severe or damaging (but not necessarily a reaction or side effect), occurred in 10% of the Q8W group, 10% of the Q4W group and 13% of the control group, but the researchers noted that none were related to the drug.
Severe drug-related adverse events were reported in 2% of the Q4W group, 4% of the Q4W group and 2% of the control group. The most common drug-related adverse events were cold-like symptoms, headache and diarrhea.
Injection site reactions, meaning pain or discomfort felt afterward at the part of the body where the injection took place, were common (97% in the Q8W group and 96% in the Q4W group) but were mostly mild and moderate, with less than 1% being classified as severe.
In terms of "virologic failure," meaning the treatment wasn't able to keep the person's viral load undetectable, there were only two cases in the Q8W group, one in the control group and none in the Q4W group. Out of these, only one in the Q8W group was linked to drug resistance (when a person's HIV develops resistance against a drug that the person is taking). However, none of these occurred after week 48 and up to week 96.
Freedom From Daily Pills
Perhaps more important than viral suppression data was the overwhelming satisfaction felt by study participants about not having to take pills every day.
Based on a survey, 99% of the Q8W group and 97% of the Q4W group reported being very satisfied with their current treatment, compared with 91% of the control group. When asked how satisfied they would be to continue their current treatment, 99% of both the Q8W and Q4W groups expressed the desire to continue long-acting injectable treatment, compared with only 78% of the control group.
"It's surprising to me -- patients at our site that are on the study -- how much they appreciate not having to take pills. I think that's something that I really didn't calculate. There's this kind of feeling of freeness from being bound to oral therapy every day," said lead study author Joseph Eron Jr., M.D., at an IAS 2017 press conference.
For now, the injections have to be administered by health care professionals, but the drug manufacturers are looking at potential ways to make the regimen self-administered.
The injectable drug regimen will move on into phase-3 clinical trials, two of which are fully enrolled, according to Eron.