UK-based Indivior has filed patent lawsuits against Dr. Reddy's, Actavis, Par, Alvogen and Teva for infringement of United States Patent No. 9,931,305 (305) regarding their respective proposed generic versions of the company's Suboxone (buprenorphine and naloxone) sublingual film product, it was reported on Friday.

These lawsuits allege that the specified companies infringe the '305 patent that was issued on April 3 and which has been submitted for listing in the United States Food and Drug Administration's (FDA's) Orange Book.

The '305 patent claims film compositions having a substantially uniform distribution of active drug. Indivior has been involved in patent infringement litigation involving other, earlier issued patents covering SUBOXONE® Film with these same companies relating to their proposed generic products.