RXi Pharmaceuticals Corp. agreed to sell up to $15 million worth of its common shares to Chicago-based investor Lincoln Park Capital Fund LLC over a 30-month period.

RXi will control the timing of any future investment under the deal, and Lincoln Park Capital will be obligated to make purchases under the agreement.

The purchase price will be based on the market price of the shares at the time of each sale to Lincoln Park Capital, and there are no upper limits to the price Lincoln Park Capital may pay for the shares.

The company will use the proceeds for working capital and general corporate purposes, including advancing its immuno-oncology pipeline, RXi said in a news release.