The US FDA has approved a new once-daily version of Merck’s antiretroviral (ARV) Isentress, known as Isentress HD. Until now, Isentress (raltegravir) had been available only as a twice-daily treatment.
Treatment with Isentress HD entails taking two 600 mg tablets once a day, compared with taking 400 mg of Isentress twice daily. The new drug has been approved for use in combination with other ARVs to treat HIV in adults and pediatric individuals of at least 40 kilograms (88 pounds) who are new to treatment for the virus or who have an undetectable viral load thanks to treatment with twice-daily Isentress. Isentress HD can be taken with or without food.
The FDA approval was based on data from the ongoing multicenter double-blind, randomized, active comparator-controlled Phase III ONCEMRK trial, which showed comparable efficacy and tolerability between Isentress HD and Isentress. The participants, first-timers to HIV treatment with a viral load of at least 1,000, were randomized to receive Truvada (tenofovir disoproxil fumarate/emtricitabine) plus either Isentress HD or Isentress.
After 48 weeks of treatment, 89 percent of the 531 participants who received Isentress HD had a fully suppressed viral load, compared with 88 percent or the 266 participants who received Isentress.
Adverse health events occurring in at least 2 percent of participants receiving either version of Isentress, included abdominal pain, diarrhoea, vomiting and decreased appetite.
Less than 1 percent of those who received Isentress HD developed mutations in their virus that led to any drug resistance.
The two versions of Isentress will be priced the same. Isentress HD should be available in US pharmacies in about four weeks.
To read a press release about the FDA approval, click here.
It is currently unknown when this new once-daily formulation of Isentress HD may become available in Australia. Presently, in Australia, Isentress is taken twice daily.