U.S. health officials on Thursday granted tentative approval for a generic liquid version of the AIDS drug AZT, allowing it to be used overseas under a U.S. program to fight HIV.

The generic oral version of GlaxoSmithKline Plc’s drug zidovudine or Retrovir, made by India-based drugmaker Aurobindo Pharma Ltd., is the latest in a string of approvals for the program.

However, the generic drug will not be available in the United States because of patent protections.

A five-year, $15 billion program launched by President George W. Bush in 2003 aims to pay for treatment for 2 million AIDS patients and provide care for 10 million others in 15 countries, mostly in Africa.

Aurobindo’s version of AZT meets the FDA’s standards, the agency said, making it eligible for purchase and use in other countries under the Emergency Plan for AIDS Relief.

The agency approved Indian drugmaker Ranbaxy Laboratories Ltd’s generic version of AZT in July as part of the U.S. program.