Cubist Pharmaceuticals Inc. has acquired two San Diego antibiotics makers — Trius Therapeutics Inc. and Optimer Pharmaceuticals Inc. — in a deal that could be worth up to $1.62 billion.

Lexington, Mass.-based Cubist will pay approximately $707 million for Trius, but it could increase to $818 million over time for Trius shareholders. Cubist will pay $535 million for Optimer, a sum which could increase to $801 million.

Cubist said its prime interest in acquiring Optimer was for rights to its antidiarrheal drug, Dificid, which was approved by the U.S. Food and Drug Administration in 2011. The drug brought in $69 million in revenue in the past 12 months, and has been lauded for its impressive sales at launch.

Cubist said it targeted Trius because of its antibiotic called tedizolid phosphate which is still under development. The powerful drug can be administered orally or intravenously, and treats dangerous gram-positive infections like methicillin-resistant Staphylococus aureus (MRSA).

“Trius and Optimer are prime examples of the high caliber innovation in San Diego we have known and respected for many years,” Mike Bonney, CEO of Cubist, said in a statement. “We have the highest regard for the talented employees at both companies. We look forward to meeting with them, listening to them, and working with them to improve the lives of patients with difficult-to-treat infections.”

— SDBJ Staff Report