HIV / AIDS
A new drug could significantly improve the chances of treatment for HIV/AIDS patients, in whom conventional drugs used in antiretroviral therapy are only poorly effective. The active ingredient lenacapavir, developed by the US pharmaceutical company Gilead, showed an effect in just over 80 percent of those treated in an efficacy study.
The scientific investigation by Sorana Segal-Maurer of New York-Presbyterian Queens Hospital is now published in the New England Journal of Medicine. “Effective antiretroviral treatment can be found for most patients with HIV-1 infection. But some patients experience multiple treatment failures due to virus resistance or side effects of the therapy,” write the scientists.
With around 38 million HIV-infected people worldwide and around 28.2 million affected people with access to antiretroviral therapy at the end of June 2021, the number of those for whom conventional drugs can also fail is large. So far, there are four main classes of AIDS drugs that primarily block enzymes of the HI virus.
New point of attack
The new active ingredient lenacapavir apparently starts at a point in the HI virus that has not yet been targeted: when the AIDS pathogen has penetrated cells, the envelope (capsid) around the RNA genetic material must change in such a way that the RNA can be released. Capsid inhibitors – such as lenacapavir – are intended to prevent these processes.
With the new efficacy study, a treatment with the new drug was to be examined for effects and side effects. Participants had to be more than 12 years old and show signs of ineffective HIV/AIDS therapy. A total of 72 patients were included in the scientific study. In some of the subjects, a placebo was initially administered in addition to the other antiretroviral therapy. In the further course, however, all participants received the new drug as an injection under the skin.
Fewer virus copies in the blood
The success: Among the 24 patients who had received the new drug from the start, the number of virus copies in the blood dropped by more than 99 percent within two weeks, while this number remained roughly the same in the twelve patients on placebo. After 26 weeks, more than 80 percent of the participants – after all, everyone received the new drug during the course of the study – had fewer than 50 HIV virus copies per milliliter of blood. This means that the infection has been brought under control.
An advantage could also be that the new drug, which was administered in tablet form for the first two weeks of the study, usually only has to be administered as an injection under the skin every six months. This makes it easier for those affected to manage their treatment.