Merck will buy antibiotic maker Cubist for $9.5 billion as part of a move to develop products that target drug-resistant infections.

The deal would expand Merck’s antibiotic portfolio by gaining access to Sivextro (tedizolid phosphate) and Cubicin (daptomycin), which generated nearly $1 billion in sales last year. The products will complement Merck’s current antibiotics such as Primaxin IV (imipenem and cilastatin) and Invanz (ertapenem), the company said.

Merck added that its pursuit of Cubist is part of a 2013 initiative to focus on hospital acute care therapies that overcome resistance mechanisms, especially those associated with gram-negative pathogens.

One of the treatments in Cubist’s pipeline, Zerbaxa (ceftolozane/tazobactam for injection), treats gram-negative pathogens. The drug has a PDUFA action date of Dec. 21, and the European Medicines Agency is expected to decide on the product in the second half of 2015.

The proposed deal comes as Cubist continues to fend off generic challenges to Cubicin. The drugmaker reached a deal with Teva that paves the way for a generic in 2018. However, Cubist sued Fresenius Kabi earlier this year over its proposed generic version of Cubicin.

Sivextro could also be hurt by generic competition. The drug is similar to Pfizer’s Zyvox, (linezolid), which is expected to go generic next year. Sivextro could struggle after Zyvox goes generic as hospitals go for the cheapest stuff, Mark Schoenebaum, an analyst for the investment firm Evercore ISI, said in a note Monday.

The deal is still subject to regulatory approvals and is expected to close by early next year. — Robert King

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