Anacor Pharmaceuticals and GlaxoSmithKline PLC (GSK) announced that GSK has exercised its option to obtain an exclusive licence to develop and commercialise GSK2251052 (GSK '052), formerly known as AN3365. GSK '052 is a novel, systemic antibiotic derived from Anacor's boron chemistry platform.

In early stage studies, GSK '052 has shown robust activity against multi-resistant gram-negative bacteria with no cross resistance to existing classes of antibiotics. GSK '052 will be developed as a potential treatment for complicated urinary tract infection (cUTI), complicated intra-abdominal infections (cIAIs), and hospital/ventilator-associated pneumonia (HAP/VAP).

Under the terms of the agreement, Anacor will receive an option exercise fee of US$ 15 million and is eligible for further development and commercialisation milestone payments and royalties on any future product sales. GSK will now assume responsibility for further development of the compound and any resulting commercialisation.

"GSK '052 has an entirely novel mechanism of action with the potential to be the first new class antibacterial to treat serious hospital gram-negative infections in 30 years," said David Payne, vice president of GSK's, Anti-bacterial Drug Discovery Unit. "Our collaboration with Anacor has enabled the rapid progression of GSK '052, and we are excited about the opportunity to address the growing need for new treatments for serious hospital acquired infections."

"The increasing prevalence of gram-negative strains of bacteria that are resistant to current antibiotics has created a significant unmet medical need that GSK '052 appears well positioned to address," said David Perry, chief executive officer of Anacor. "GSK has been an excellent development partner and we are confident that their continued commitment will help ensure that this important compound can reach its fullest potential."

GSK '052 is a novel boron-based, small-molecule candidate that targets the bacterial enzyme leucyl tRNA synthetase.

In October 2007, GSK and Anacor entered into a worldwide strategic alliance for the discovery, development and commercialization of novel medicines for viral and bacterial diseases. The collaboration provides GSK access to Anacor's proprietary boron-based chemistry for use in four target-based project areas.

Anacor is a biopharmaceutical company focused on discovering, developing and commercializing novel small molecule therapeutics derived from its boron chemistry platform.