Sorrento Therapeutics Inc. has announced a proposed offering of its common stock, but hasn’t disclosed the size of the offering.

Sorrento Therapeutics (Nasdaq: SRNE) develops pain medication and cancer drugs, and uplisted last year to the Nasdaq with a $35 million stock offering. In recent months, it has launched a new subsidiary called Ark Animal Therapeutics and acquired a small San Diego biotech called Concortis Biosystems Corp. for about $11.3 million.

Last year, it acquired companies including New York-based Sherrington Pharmaceuticals Inc. and Fountain Valley-based Igdrasol Inc. for undisclosed sums. Sorrento also transitioned to the Nasdaq and recently closed a $35 million stock offering.

Aegis Capital Corp. is acting as the sole book-running manager for the offering.