GlaxoSmithKline has received fast track designation for the HIV protease inhibitor (PI) 640385 (VX-385) from the United States Food and Drug Administration. GSK plans to initiate a Phase IIb study of 640385 in HIV-infected patients in the third quarter of 2005. 640385 is the third, orally active HIV protease inhibitor to be developed as part of the collaboration agreement between Vertex Pharmaceuticals and GSK.

“The Food and Drug Administration’s fast track designation for 640385 highlights the productive collaboration between Vertex and GlaxoSmithKline, which has generated three novel HIV protease inhibitor product candidates over the past 12 years, and has established both companies as leaders in the development of new drugs to treat HIV infection,” said Joshua Boger, chairman, president and CEO of Vertex.

Support of this fast track designation was based on positive Phase IIa data from a clinical study of 640385 in HIV-infected patients, as well as results from in vitro studies indicating 640385’s antiviral activity against HIV-1 strains resistant to a number of currently marketed protease inhibitors. Vertex expects that GSK will present preliminary Phase IIa results at a medical conference in the second half of 2005.