Merck & Co's Isentress launched in UK

US drug major Merck & Co's HIV integrase inhibitor Isentress (raltegravir) has been launched in the UK. Available as 400mg tablets, the agent is approved for use in combination with other antiretrovirals for HIV-1 infection in treatment-experienced adult patients with evidence of replication despite ongoing antiretroviral therapy. 24-week outcomes from two pooled studies have shown that 75% of patients receiving Isentress plus optimized background therapy achieved HIV viral load reduction to less than 400 copies/ml compared to 40% on placebo plus OBT, while 63% versus 34% achieved load reduction to less than 50 copies/ml.