Depomed buys rights to pain drug Zipsor for $26 million

Depomed Inc. bought the rights to the pain treatment Zipsor from Xanodyne Pharmaceuticals Inc. for $25.9 million in cash.

Menlo Park-based Depomed (NASDAQ: DEPO) also agreed to possible milestone payments based on how well the drug (diclofenac potassium) sells. It typically brings in $19 million a year.