Drug developer Targacept (Nasdaq: TRGT) lost $15.9 million in the fourth quarter of 2012 as the company grappled with reduced revenue and higher expenses from a corporate restructuring. 

The restructuring, which trimmed Targacept’s headcount nearly in half, followed the failure of the Winston-Salem company’s lead drug — a depression treatment — in phase III clinical trials. The company has refocused its efforts on its remaining compounds in phase II studies.

Targacept reported just $590,000 in fourth quarter revenue, down from $18.9 million a year ago. Although Targacept has no Food and Drug Administration-approved drugs, the company drew revenue from alliances with larger drug companies, who helped finance drug development work. The steep revenue drop is linked to Targacept’s loss of partnerships with GlaxoSmithKline (NYSE:GSK) and AstraZeneca (NYSE:AZN). The GSK partnership ended in 2011. AstraZeneca had collaborated with Targacept on the experimental depression treatment. But shortly after that compound failed in phase III  trials last winter, that partnership terminated as well. AstraZeneca remains a partner with Targacept on other compounds.

Targacept’s restructuring charges for the fourth quarter were $1.4 million. For the year the company reported $3.7 million in restructuring charges.