Cubist Pharmaceuticals, Inc. (NASDAQ: CBST) today announced that company management will present at four investor conferences during September to discuss the company’s business activities, financial outlook, and current news.

• Robert Perez, EVP and COO, will present on Wednesday, September 9, at 8:00 a.m. Eastern Time, at the Thomas Weisel Partners Healthcare Conference being held at the Four Seasons Hotel in Boston. (Live audio-only webcast.)
• Steven Gilman, SVP and CSO, will present on Wednesday, September 16, at 1:45 p.m. Pacific Time, at the 6^th Annual ThinkEquity Conference being held at the St. Regis Hotel in San Francisco. (Live audio with slides webcast.)
• Michael Bonney, President and CEO, will present on Monday, September 21, at 4 p.m. Eastern Time, at UBS Global Life Sciences Conference being held at the Grand Hyatt in New York City. (Live audio with slides webcast.)
• David McGirr, SVP and CFO, will present on Tuesday, September 22, at 8:50 a.m. Eastern Time, at the Banc of America Merrill Lynch Conference being held at the InterContinental Hotel in Boston. (Live audio with slides webcast.)

All of the presentations are accessible through Cubist’s website at www.cubist.com in the Investor Relations Conference Calendar section and will be available there for a period of 30 days after the presentations.

About Cubist

Cubist Pharmaceuticals, Inc. is a biopharmaceutical company focused on the research, development, and commercialization of pharmaceutical products that address unmet medical needs in the acute care environment. In the U.S., Cubist markets CUBICIN® (daptomycin for injection), the first antibiotic in a new class of anti-infectives called lipopeptides. In July 2008, Cubist entered into an agreement with AstraZeneca to promote their established antibiotic, MERREM® I.V. (meropenem for injection) in the U.S. The Cubist product pipeline includes ecallantide, a recombinant human protein in Phase 2 clinical trials — CONSERV™-1 and CONSERV™-2 — for the reduction of blood loss during cardiac surgery, and two Phase 1 programs that address unmet medical needs, one in CDAD (Clostridium difficile-associated diarrhea) and the other in multi-drug resistant (MDR) Gram-negative infections. In addition, the Company, in collaboration with Alnylam Pharmaceuticals, Inc. (Cambridge, MA), has a pre-IND and a Phase 2 program underway in novel treatments for respiratory syncytial virus infections using Alnylam’s RNA-interference technology. Cubist is headquartered in Lexington, MA. Additional information can be found at Cubist’s web site at www.cubist.com.

Cubist and CUBICIN are registered trademarks of Cubist Pharmaceuticals, Inc.

AstraZeneca and MERREM are registered trademarks of the AstraZeneca group of companies.