As it prepares to begin Phase I testing later this year with its lead compound aimed at methicillin-resistant Staphylococcus aureus, Affinium Pharmaceuticals Inc. brought in $18 million in an oversubscribed Series A round.

It's the Toronto-based firm's first financing since it restructured in 2005 to shift the focus from a research operation to a research and clinical business model aimed at developing anti-infective drugs targeting the bacterial fatty acid biosynthesis (Fab) pathway.

Affinium's lead candidate, API-1252, has shown promising early activity and helped the company "attract a lot of interest this year," said Owen Roberts, Affinium's chief financial officer.

Among the interested parties was San Diego-based Forward Ventures, which led the Series A round, with participation from Oxford Bioscience Partners, of Boston, and SV Life Sciences, of San Francisco, and existing investor Genesys Capital, of Toronto.

While a number of companies are working in the antibiotic space to counter the growing resistance problem seen with existing treatments, Affinium is only one of a few working "on a truly innovative approach," said Stuart Collinson, of Forward Ventures, who also serves as Affinium's chairman.

The company's work is not based on "a variation of existing antibiotics," Collinson told BioWorld Today, but "rather a brand new class of drugs." Aimed at hitting the Fab1 enzyme, API-1252 has shown activity when administered both orally and intravenously against infections caused by staph bacteria, including MRSA, and, so far, has indicated a low rate of resistance. Those data, combined with the "very high unmet need" for treating both hospital- and community-acquired staph infections, helped to capture investor attention, he added.

Funds from the recent round are expected to support upcoming clinical testing of API-1252 through Phase IIa, which should take less than three years, Roberts said. Affinium hopes to have Phase I completed "by the end of the year."

Beyond API-1252, the company has a library of 1,700 compounds, though, at this time, it has not selected any others for further development.

Initially founded in 2000 as Integrative Proteomics Inc., the company's early work centered on a proteomics and structure-guided drug discovery platform. It raised about $33 million in financings in 2000 and 2001. In February 2002, the company became Affinium and, a year later, acquired worldwide rights to its antibacterial program from London-based GlaxoSmithKline plc in exchange for an equity stake in the company. (See BioWorld Today, Feb. 27, 2003.)

That compound technology was "put into our research engine" and API-1252 emerged from that, Roberts said. After completing Phase II studies, Affinium likely would seek a partnership opportunity or an outright sale of the program.

The company recently was awarded a two-year $4.8 million research contract with the Defense Threat Reduction Agency, a unit of the Department of Defense, for preclinical work on selected Fab inhibitor compounds. In that biodefense capacity, the compounds will be evaluated against pathogens, such as Francisella tularensis, which could be potential biological warfare or bioterrorism agents.