While new HIV prevention methods got the most attention at this year’s Conference on Retroviruses and Opportunistic Infections (CROI), which took place last week in Boston, researchers also presented studies of new drugs for HIV therapy. Two of these are being tested for both treatment and pre-exposure prophylaxis (PrEP).
Long-Acting Cabotegravir and Rilpivirine
The most exciting prospect are long-acting injectable antiretrovirals that can be taken once monthly or even quarterly. Long-acting medications could offer an attractive option for people with HIV facing a lifetime of treatment.
David Margolis, M.D., from ViiV Healthcare presented findings from the LATTE 2 trial, which tested a pair of long-acting injectables—cabotegravir and rilpivarine—for HIV maintenance therapy.
In preparation for testing the long-acting injectables, the original LATTE study previously showed that oral cabotegravir plus oral rilpivirine (Edurant) was safe and maintained viral suppression in people who achieved undetectable viral load using a standard three-drug regimen. Demonstrating the safety and effectiveness of an oral version of this regimen was important because the injectable versions cannot be removed from the body after administration.
The 309 previously untreated participants in LATTE 2 first started a three-drug regimen containing oral cabotegravir plus abacavir/lamivudine (the drugs in Epzicom). The 286 people who achieved viral suppression then went on to the maintenance phase, where they were randomly assigned to receive intramuscular injections of cabotegravir and rilpivirine every 4 weeks (Q4W), every 8 weeks (Q8W), or to stay on the same oral regimen.
During the maintenance phase, 94% of participants who received the injections every 4 weeks and 95% of those treated every 8 weeks maintained undetectable viral load at 32 weeks, as did 91% of those who stayed on the oral regimen.
Injectable cabotegravir and rilpivirine were generally safe and well tolerated with few serious adverse events. However, more than 90% of participants who received the shots reported injection site reactions such as pain or swelling. The regimen requires two separate 2-3 ml injections of cabotegravir and rilpivirine in the gluteal muscle (the butt), which is quite a large volume. Most of these reactions were mild or moderate and usually resolved in about three days. Only two people withdrew from the study for this reason.
Despite the injection problems, study participants reported a high level of satisfaction with their treatment. More than 90% of people taking the long-acting injectable said that they were satisfied, compared to about 70% of those on the oral regimen.
This excerpt was cross-posted with the permission of BETAblog.org. Read the full article.