(Reuters) - GlaxoSmithKline’s experimental HIV injection is as effective when given every other month as monthly, according to a study, a convenience that could help the British drugmaker in its battle against a rival drug from Gilead Sciences.GSK’s two-drug injection was as effective as a monthly dose of the same regimen in maintaining viral suppression at 48 weeks in a late-stage study, said ViiV Healthcare, GSK’s HIV unit.
Detailed results will be presented at an unspecified medical conference, the company added.
ViiV, in which Pfizer and Shionogi have small stakes, is working on two-drug combinations and will use the lower drug burden in comparison with three-drug cocktails such as Gilead’s Biktarvy as its main selling point to patients and physicians.
It is banking on longer-term studies to yield hard evidence of fewer side effects over time.
ViiV has taken a two-pronged approach.
While its once-a-day pill Dovato, also a two-drug combination, won U.S. market approval in April, the company is following up with a longer-acting injection combining the two active ingredients cabotegravir and Janssen’s rilpivirine.
The injection has previously proven to be as effective as standard daily pills with three active ingredients when administered monthly. Thursday’s results showed that doubling the time between injections does not compromise efficacy or safety.
Injections - targeted at patients unable to take, or not comfortable with, daily pills - are, however, seen as a smaller market opportunity than oral medicines.
“This is further progress in our efforts to reduce the number of medicines a person living with HIV must take while also reducing the frequency of treatments,” said Kimberly Smith, Head of Research & Development at ViiV.
The trial focused on the HIV-1 category of the AIDS virus, which has the most widespread strains. If not quelled, an HIV infection causes AIDS, a deadly condition that severely weakens the immune system.
U.S. drugmaker Gilead dominates the HIV market and it will keep up the pressure with fast-growing Biktarvy, which was approved early last year. Analysts on average expect sales from the product to reach $5 billion next year, according to Refinitiv data.
Editing by Mark Potter