Gilead’s High Bar for AIDS Drugs Means New Development Withers

Gilead Sciences Inc., the world’s biggest AIDS-drug maker, revolutionized treatment and helped forge a $15 billion market with a single daily pill attacking the virus with three medicines at once.

Now, Foster City, California-based Gilead and rivals Merck & Co. and Bristol-Myers Squibb Co. are victims of that success. Three decades after the discovery of the virus that causes AIDS, there are 31 drugs on the market that have helped turn HIV from a death sentence into a manageable disease in the developed world. Only six were approved after 2004.