Sandoz International and its Switzerland-based subsidiary have been released from a patent infringement suit that aims to protect Genentech Inc.'s pulmonary fibrosis treatment from generic competition.

A Delaware federal judge on Thursday approved an agreement by San Francisco-based Genentech and Sandoz to dismiss the two entities, without prejudice, from the lawsuit, because neither had been involved in filing an abbreviated new drug application at the heart of the dispute.

Under the agreement, submitted to the court Wednesday, Sandoz International and Sandoz AG would still be bound by any decision that U.S. District Judge Richard G. Andrews of the District of Delaware may enter in the case, as if they were named defendants in the case.

The move leaves only Sandoz Inc., the company's U.S. subsidiary, to face claims in the suit that its planned generic infringes 16 patents covering Esbriet, Genentech's drug for slowing the progression of IPF, a fatal disease which causes scarring of the lungs and thus prevents the body's vital organs from receiving enough oxygen to function properly.

Genetech, a subsidiary of the Roche Group, said in a January court filing that Esbriet gained Food and Drug Administration approval in 2014, shortly after it acquired the biotechnology company InterMune Inc., which developed the drug and owns the patents. According to the complaint, the FDA accorded Esbriet status as a breakthrough therapy, and awarded it orphan drug exclusivity through October 15, 2021.

Genentech said its action arose when Sandoz sent the company a letter in December, notifying it that had filed its ANDA and planned to seek approval for a commercial launch before the exclusive patent rights expired.

“Sandoz now seeks to piggy-back on Plaintiffs' hard work by seeking FDA approval of the Sandoz ANDA that cross-references and relies upon Plaintiffs' clinical trial data,” Genentech's Loeb & Loeb and Morris, Nichols, Arsht & Tunnell attorneys wrote in the 45-page complaint.

“In so doing, Sandoz has not conducted any of the clinical trials needed to demonstrate effectiveness and safe conditions of use for its proposed Sandoz ANDA product. Rather, Sandoz asks that the FDA permit the Sandoz ANDA to rely on proprietary clinical data submitted by Plaintiffs InterMune and Genentech,” they said.

Sandoz is expected to file its response to the complaint Friday, according to the case docket.

Under the dismissal agreement, Sandoz has agreed not to contest personal jurisdiction, subject matter jurisdiction or venue in the case.

Roche reported earlier this year sales of Esbriet topped $1 billion in 2018. However, competitors have been lining up to challenge the drug's blockbuster status, leading Genentech to file at least 18 lawsuits to block generic versions of the drug, according to media reports.

Genentech is represented by Mark E. Waddell, Warren K. MacRae and Ryan Hagglund of Loeb & Loeb in New York and Jack B. Blumenfeld and Karen Jacobs of Morris Nichols in Wilmington.

Sandoz is represented by Elaine Herrmann Blais, Emily L. Rapalino and Srikanth K. Reddy of Goodwin Procter in Boston and Natasha E. Daughtrey from the firm's office in Los Angeles Stephen B. Brauerman of Bayard in Wilmington is acting as local counsel.

The case is captioned Genentech v. Sandoz.