Microcap M&A

Mast Therapeutics Inc. (NYSE-M:MSTX) doesn't view M&A as a surefire way to scale up, but the microcap hopes its second opportunistic deal in three years can add enough value to attract investors and improve its access to capital.

Mast began life as Adventrx Pharmaceuticals Inc., but in March 2009 the company discontinued development of all its assets and restructured. It had less than $15 million in cash and a market cap of $16 million...