More dual HIV regimens are coming

The pharmaceutical company ViiV Healthcare has been the leader in developing potent dual-drug HIV regimens, such as the following:

• Juluca – a pill containing dolutegravir + rilpivirine; this is meant to be taken once daily for maintenance therapy. That is, a person whose viral load has been stably suppressed on standard triple therapy can be considered for a switch to Juluca. As they are already virologically suppressed, it is not surprising that clinical trials have shown that Juluca continues to suppress HIV.

Dovato – a pill containing dolutegravir + 3TC; this is meant to be taken once daily either as initial or maintenance treatment for HIV.

ViiV is also developing a long-acting injectable regimen. This is how it works: First, patients are initiated on standard oral treatment that suppresses their viral load. After several months of oral treatment and the achievement of a suppressed viral load (less than 50 copies/mL), and provided no sustained or serious side effects occur, they can be switched to injectable treatment, likely given every two months. Injectable treatment consists of two drugs: cabotegravir and rilpivirine. Clinical trials have shown that such injectable treatment is well tolerated and works at suppressing HIV.

Other companies will test dual regimens

Another pharmaceutical company, Merck, is also entering the dual-regimen field. Merck plans to test a combination of a non-nuke called doravirine with a new drug called islatravir (formerly MK-8591) in people new to HIV treatment as well as a form of switch therapy in people who are using standard triple therapy. We will have more information about islatravir in the future.

Another leader in the field of HIV treatment and prevention is Gilead Sciences. It is said that Gilead plans to consider testing a dual-drug regimen. Details are not available at this time.

In the early 1990s, HIV treatment for some people consisted of dual-drug regimens, such as AZT + 3TC or AZT + ddI. Such regimens based on nucleoside analogues did not confer benefit for long and were toxic. Today, dual therapy has returned, with more powerful and safer therapies anchored by integrase inhibitors and possibly other classes of drugs in the future.

The next decade holds the promise of dual therapy for both initiating ART and as maintenance/switch therapy in virally suppressed patients.

—Sean R. Hosein