Merck & Co has added to its early-stage product pipeline by licensing worldwide rights to an HIV protease inhibitor programme in development at Canadian biotech Ambrilia Biopharma.

Under the terms of the agreement, Merck will pay $l7 million upfront along with up to $215 million upon successful completion of development, clinical, regulatory and sales milestones. It will also pay royalties on all future product sales.

Merck already has an HIV/AIDS therapeutic franchise with its Crixivan (indinavir) and Stocrin (efavirenz) products, and recently boosted this by securing co-promotion rights to a Gilead Sciences and Bristol-Myers Squibb’s new triple HIV therapy – Atripla (efavirenz, emtricitabine and tenofovir), in Europe. Ambrilia's lead compound, PPL-100, is currently in early-stage clinical trials.

Ambrilia said it intends to use the revenue from the Merck agreement to help fund the development of other technologies and product candidates in its portfolio.