Shionogi-ViiV to file HIV drug dolutegravir for approval

Shionogi-ViiV Healthcare has completed its phase III trials programme for new HIV drug dolutegravir and says it plans to file for approval before the end of the year.

The joint venture between Japan's Shionogi and HIV specialist ViiV - set up by GlaxoSmithKline and Pfizer in 2009 - said it now has data on the use of dolutegravir in HIV-positive individuals already treated with antiretroviral therapy to complement earlier studies in treatment-naïve patients.

Dolutegravir is an HIV integrase inhibitor in the same class as Merck & Co's $1.6bn blockbuster Isentress (raltegravir) and Gilead Sciences' elvitegravir, which was approved in the US in August as part of four-drug HIV therapy Stribild and has also been filed for approval as a single-agent product.

The drugs are designed to block HIV's entry into cells and are used in combination with other antiretroviral agents.

Shionogi-ViiV has data from two studies in treatment-experienced patients, both of which are still ongoing, with data due to be reported at medical conferences in the coming months.

The first of these is VIKING-3, which is examining dolutegravir at a twice-daily 50mg dose in treatment-experienced adults with HIV-1 who have shown resistance to raltegravir or elvitegravir.

Meanwhile, SAILING is comparing dolutegravir 50mg once-daily to raltegravir 400mg twice-daily in treatment-experienced, integrase inhibitor-naive adults with HIV-1.

Previously, Shionogi-ViiV reported data from two studies in treatment-naïve patients which indicated that dolutegravir was more effective than currently-used drug regimens.

The SINGLE study found dolutegravir plus ViiV's Kivexa/Epzicom (abacavir/lamivudine) was more effective than Gilead and Bristol-Myers Squibb's widely-used triple therapy for HIV Atripla (efavirenz/emtricitabine/tenofovir disoproxil fumarate), which achieved almost $2bn in sales in the first half of 2012.

Moreover, the SPRING-2 trial showed that once-daily dolutegravir was at least as effective as twice-daily raltegravir in treatment-naïve patients.

The favourable efficacy data and dosing frequency have prompted analysts to predict blockbuster sales for dolutegravir, with JPMorgan Chase & Co predicting $5bn in peak annual turnover.