By Ben Hirschler
LONDON (Reuters) - GlaxoSmithKline is banking on new long-acting HIV medicines and simple two-drug regimens to close the gap on arch-rival Gilead Sciences (NASDAQ:GILD).
Dominique Limet, chief executive of GSK's majority-owned ViiV Healthcare unit, believes the line-up will help GSK rejuvenate its position in HIV treatment.
Although GSK used to dominate the HIV market, ViiV's 2014 sales of 1.5 billion pounds were less than a quarter the HIV revenue generated by market leader Gilead.
That is a gap Limet aims to close in the coming years, helped by the success of Tivicay, or dolutegravir, a so-called integrase inhibitor that blocks a key enzyme used by HIV to multiply.
The medicine is already a key component in Triumeq, a three-in-one combination approved by regulators last year, and it also forms the bedrock of new two-drug combinations in development.
"We have a growth rate that is very substantial and we have beaten the competition in many markets with the launch of Tivicay and Triumeq," Limet told Reuters in an interview. "With the dual regimens we now have a portfolio of new assets that will allow us to maintain that growth momentum."
ViiV is also developing another long-acting integrase inhibitor called cabotegravir for use in HIV drug cocktails.
Since the 1990s, drugmakers have relied on mixing at least three medicines together to fight HIV because of the ability of the virus that causes AIDS to mutate and become drug-resistant.
Dolutegravir, however, has a superior resistance profile to other approved HIV medicines, opening the door to two-drug combinations, which may be cheaper and have fewer interaction issues with other medications.
The latter point is important as more than half of HIV patients are expected to be over 50 by 2030 and will be on a variety of drugs for other common conditions associated with old age.
Final-stage Phase III studies on the first two-drug regimen, combining dolutegravir with Johnson & Johnson's rilpivirine, are now under way and other combinations are planned.
HIV is a rare bright spot in GSK's troubled pharmaceuticals business, where its market-leading respiratory medicine Advair is in decline and a successor product, Breo, recently suffered a setback.
GSK, which has a 78 percent stake in ViiV alongside Pfizer and Shionogi, scrapped plans in May for a partial initial public offering of the HIV business and reaffirmed its commitment to the unit.
"We represent a major growth contributor to GSK's future," Limet said.
By 2020, analysts believe that Tivicay and Triumeq together could have annual sales of $4.5 billion, according to consensus forecasts compiled by Thomson Reuters Cortellis.
Bank of America (NYSE:BAC) Merrill Lynch said in a report this month that Tivicay and Triumeq peak sales were likely to hit $7 billion in 2023.
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