Bristol-Myers said Tuesday that U.S. government regulators will help speed up development for one of its experimental HIV drugs.

The Food and Drug Administration designated the BMS-663068 as a breakthrough treatment, so Bristol-Myers Squibb Co. will get extra meetings with the FDA and earlier communication with scientists as it studies the drug. BMS-663068 is intended to be used with other in adults who have already developed resistance to several other types of HIV treatments. Bristol-Myers is running late-stage clinical tests of the drug.

There are six classes of HIV drugs, according to the National Institutes of Health, and patients are typically treated with drugs from at least two different classes at any given time. After years of treatment patients sometimes develop resistance to those drugs, and if they develop resistance to several types of drugs, their doctors may not be able to assemble an effective treatment regimen.

Bristol-Myers is studying BMS-663068 in patients who have two or fewer drug classes left available to them. The drug is designed to stick to HIV cells and stop them from binding to a type of white blood cell. The company says BMS-663068 doesn't fit into the six current classes of HIV therapy.

Bristol-Myers sells the HIV drugs Reyataz, one of its top products by revenue, and Evotaz, which was approved in January, and it is studying several other treatments for the disease. However it announced in June that it will end early-stage research in HIV as well as hepatitis B so it could focus on other fields, including drugs that stimulate the immune system to fight cancer.

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