(Corrects July 10 story to show patients switched from Gilead's Descovy, not Gilead's Vemlidy, in fifth paragraph)
July 10 (Reuters) - GlaxoSmithKline Plc's two-drug HIV regimen Dovato was successful in suppressing the AIDS-causing virus in patients over 48 weeks at the same level of a previous three-drug treatment in a late-stage trial, the drugmaker said on Wednesday.
Dovato, a combination of dolutegravir and lamivudine, was approved in the United States in April for newly-diagnosed patients, boosting the British drugmaker's prospects against Gilead Sciences Inc, which currently leads the HIV treatment market.
Liberium analyst Graham Doyle said the study results will add to the data package supporting Dovato as GSK aims to convince doctors that two drug therapies are just as effective as triple therapies.
GSK is betting that a shift to using two drugs rather than three will boost its sales by offering patients a therapy with fewer potentially toxic side effects.
The study evaluated the effectiveness of Dovato, a combination of dolutegravir and lamivudine, in adults with the HIV-1 virus who switched to the regimen from at least a triple combination containing Gilead Sciences' Descovy, the British company's HIV drugs division ViiV said.
ViiV also said adults who used Dovato did not develop any resistance to the treatment.
GSK already has a two-drug regimen Juluca on the market, but only for HIV patients that have received prior treatment.
Pfizer Inc and Shionogi & Co Ltd also have small stakes in ViiV, which accounted for about 39% of GSK's group operating profit last year, according to UBS analysts.
The HIV-1 category has the most widespread strains of the virus, which severely affects the body's immune system. (Reporting by Pushkala Aripaka in Bengaluru; Editing by Bernard Orr)