Johnson & Johnson said on Monday it had filed a lawsuit against Samsung Bioepis for breaching its contract agreement with the drugmaker over the launch of a biosimilar to Stelara, J&J's autoimmune drug.

Samsung Bioepis allegedly entered into an agreement with a third-party health company, allowing it to market its own private label of a Stelara biosimilar.

Johnson & Johnson (NYSE:JNJ) is reportedly suing Samsung Bioepis for breach of contract related to the launch of a biosimilar of J&J's blockbuster drug Stelara, also known as ustekinumab. In its suit,

As biosimilar versions of a big-selling Johnson & Johnson medicine reach the U.S. market, the health care giant accused one manufacturer of striking a