A once-a-week pill for treating HIV has shown promising results in a major international clinical trial, raising the possibility that Kenyans on antiretroviral treatment could eventually have an alternative to taking tablets every day.
The findings, presented at the ongoing International Aids Conference in Rio de Janeiro and published in the New England Journal of Medicine, come from a Phase 3 trial involving 607 adults in 12 countries.
Phase 3 trials are the final stage of testing before drug makers seek approval from regulators, meaning the weekly pill is still under evaluation and is unlikely to become widely available for at least another year or two if approved.
The new tablet combines two long-acting HIV medicines, islatravir and lenacapavir, into a single pill taken once every seven days instead of every day. Researchers say it could become an important new option for people whose HIV is already well controlled on treatment.
Kenya has about 1.4 million people living with HIV, with around 1.39 million currently receiving life-saving antiretroviral therapy. While daily medicines have transformed HIV into a manageable long-term condition, taking tablets every day for life can still be challenging for some people because of treatment fatigue, stigma or the burden of taking several medicines.
“Treatment needs to fit into people's lives, not the other way around,” incoming International Aids Society president Dr Kenneth Ngure of Jomo Kenyatta University of Agriculture and Technology said.
“People living with HIV need new treatment options that offer flexibility, and a weekly pill could broaden the choices available for adults with virological suppression.”
In the international trial, adults whose HIV had remained suppressed on standard daily treatment were randomly assigned either to switch to the weekly tablet or continue taking their existing daily medicines.
After 48 weeks, the weekly regimen proved just as effective as the standard daily treatment. More than 93 per cent of participants in both groups maintained viral suppression, while none of those taking the weekly pill experienced virological failure during the study.
Prof Chloe Orkin of Queen Mary University of London, the study's senior author, said the findings could make treatment easier for many people living with HIV.
"The first ever weekly oral therapy for the treatment of HIV could offer welcome relief from the burden of life-long daily pill-taking for people living with HIV. This is especially important for people that are experiencing stigma and people with other HIV-associated health conditions who are taking multiple other tablets," she said.
The researchers said the study addresses one of the remaining challenges in HIV care. Although modern medicines have dramatically improved survival, taking tablets every day can still be difficult for some patients.
“Once-daily, single-tablet regimens have transformed care for persons living with human immunodeficiency virus type 1 (HIV-1); however, challenges to adherence continue to limit effective treatment," the study notes.
It adds that long-acting oral-drug combinations could offer new options with less frequent dose administration.
The authors said daily treatment can lead to pill fatigue, describing it as mental, emotional, or behavioural weariness associated with taking medication on a regular basis. They noted that people living with HIV have shown interest in longer-acting treatments with either injectable or oral agents, with a preference for the latter.
The ISLEND-1 trial enrolled 607 adults across 106 clinical sites in 12 countries. Participants whose HIV had been suppressed for at least six months on a standard daily regimen either switched to the weekly tablet or remained on their existing treatment. Researchers then compared how well each group maintained viral suppression over 48 weeks.
The weekly treatment also showed a similar safety profile to the daily medicines. Serious adverse events occurred in about five per cent of participants in both groups, while around two per cent stopped treatment because of side effects. No deaths were reported during the trial.
The trial is continuing, with participants expected to be followed for a total of 96 weeks to assess longer-term safety and effectiveness before regulatory authorities decide whether to approve the treatment. Because this is a Phase 3 trial, researchers are collecting the final evidence needed to demonstrate that the medicine is safe and effective enough for routine clinical use.
In their discussion, the researchers said the findings suggest the weekly pill could become another treatment option for people living with HIV who prefer taking medicine less often.
"There remains a need for treatment options that can provide more flexibility and decrease pill fatigue. Once-weekly ISL/LEN represents a potential treatment option for a complete, single-tablet, oral regimen for the treatment of HIV-1,"the researchers said.
