A federal judge has paved the way for generic entry of Cubist’s antibiotic Cubicin by 2016 after nixing four out of five patents challenged by Hospira.

The Delaware federal district court judge ruled that the ’967, ’689, ’238, and ’342 patents protecting Cubicin (daptomycin for injection) were all invalid, either due to anticipation in prior scientific knowledge or because they were obvious for other drugmakers to try.

The only patent the judge upheld as valid was the RE’071, which is set to expire in June 2016 according to the Orange Book. The other challenged patents run until 2019 or 2020.

Hospira challenged Cubicin in 2012 with both a Paragraph IV ANDA against its 500 mg/vial dose and a 505(b)(2) NDA targeting its 350 mg/vial version, according to the ruling.

Cubicin’s voided patent protection means both Hospira and at least one other generic will likely launch in 2016. In 2011, Cubist settled a patent infringement lawsuit with Teva that allowed the Israeli firm to market its own version by 2018 or earlier if another company puts out its own Cubicin generic, as is likely the case here. Cubist is also currently battling a separate Paragraph IV patent challenge filed against Cubicin this spring by Fresenius Kabi.

Hospira is currently reviewing the decision and considering its options, the company said. That could include an appeal to invalidate the RE’071 and pave the way for launch sooner. Cubist has also said it would appeal the decision.  

   
Further complicating Cubicin’s fate is the recent purchase of Cubist by Merck in a $9.5 billion deal that is still subject to regulatory approval. Both companies said that the ruling would not affect the merger.  

Cubicin generated $908 million in sales last year, according to financial filings. — Bryan Koenig

Originally appeared in Drug Industry Daily, the pharmaceutical industry’s number one source for regulatory news and information. Click here for more information.