FDA Approves Cubicin
FDA Approves Cubicin, Previously Cidecin, an Antibiotic Developed by Cubist Pharmaceuticals


The Only Once-Daily, Rapidly Bactericidal Antibiotic Proven Effective Against Both MRSA and MSSA

LEXINGTON, Mass., Sep 12, 2003 (BUSINESS WIRE) -- Cubist Pharmaceuticals, Inc. (Nasdaq: CBST) today announced that the U.S. Food & Drug Administration (FDA) has approved Cubicin(TM) (daptomycin for injection; previously known as Cidecin(R)) for the treatment of complicated skin and skin structure (cSSS) infections caused by Gram-positive bacteria, including those caused by MRSA (methicillin-resistant Staphylococcus aureus) and MSSA (methicillin-susceptible S. aureus). Cubist anticipates the product to be available to physicians and hospitals by early November.

"The approval of CUBICIN is particularly important as we face the growing public health crisis of bacterial resistance," said Robert A. Weinstein, MD, Chairman of the Division of Infectious Diseases at Stroger Hospital of Cook County in Chicago and a Cubist scientific advisor. "There has been a frightening increase in MRSA infections over the past decade, and the tools currently available to combat this problem have become less effective. The approval of CUBICIN gives physicians a new weapon against cSSS infections, particularly to treat the estimated 600,000 U.S. patients who contract MRSA cSSS infections each year."

CUBICIN is an antibacterial agent from a new class of antibiotics called cyclic lipopeptides, and has clinical utility in the treatment of infections caused by aerobic Gram-positive bacteria. The in vitro spectrum of activity of CUBICIN encompasses most clinically relevant Gram-positive pathogenic bacteria, including bacterial isolates resistant to methicillin, vancomycin and linezolid. In the U.S., MRSA now accounts for nearly 60% of staphylococcus infections in hospitals, and the incidence of MRSA in the community is on the rise as well.

The New Drug Application (NDA) for CUBICIN included safety data from 1,409 subjects receiving drug in Cubist-sponsored studies, data on the in vitro activity spectrum of CUBICIN against approximately 21,000 global clinical bacterial isolates, and clinical efficacy data from two pivotal Phase 3 studies in cSSS infections. In these studies, CUBICIN met the prospective endpoint of demonstrating equivalency to the gold standard treatments (either vancomycin or a semi-synthetic penicillin such as oxacillin or nafcillin) in the treatment of cSSS infections. In the clinically evaluable population, the clinical success rate for daptomycin was 83.4% and for comparator was 84.2%. The clinical success rates by infecting pathogen in the microbiologically evaluable population were as follows:

                                                 Success Rate(1)
Pathogen                                      Cubicin    Comparator(2)
                                              n/N (%)       n/N (%)
Methicillin-susceptible S. aureus (MSSA)c 170/198 (85.9)180/207 (87.0)
Methicillin-resistant S. aureus (MRSA) c    21/28 (75.0)  25/36 (69.4)
Streptococcus pyogenes                      79/84 (94.0)  80/88 (90.9)
Streptococcus agalactiae                    23/27 (85.2)  22/29 (75.9)
Streptococcus dysgalactiae subsp.
 equisimilis                                   8/8 (100)   9/11 (81.8)
Enterococcus faecalis
(vancomycin-susceptible only)               27/37 (73.0)  40/53 (75.5)
(1) Success was defined as:  clinical resolution or improvement with
    no further antibiotic therapy required
(2) Comparator agents were either vancomycin or a semi-synthetic
    penicillin such as oxacillin or nafcillin

CUBICIN has been approved for intravenous administration at 4 mg/kg once-daily. U.S. Patent No. 6,468,967 provides U.S. market exclusivity for the once-daily administration of CUBICIN until 2019. Cubist licensed worldwide rights to CUBICIN from Eli Lilly and Company in 1997.

"With the approval of CUBICIN today, Cubist joins an elite group of biopharmaceutical companies that have transitioned from discovery-based start-ups to operating companies," said Michael W. Bonney, President & CEO of Cubist. "This approval not only brings a valuable new antibiotic treatment option to the medical community, but also represents years of dedicated effort by Cubist employees and collaborators. We are extremely proud of this accomplishment, which would not have been possible without the support of our many stakeholders. We would also like to acknowledge the FDA for completing their review of the NDA for CUBICIN within nine months of our December 2002 filing date." Mr. Bonney concluded, "With our sales force and commercial infrastructure now complete, we will soon begin educating physicians and pharmacists about CUBICIN, with product shipping targeted for early November."

To reduce the development of drug-resistant bacteria and maintain the effectiveness of CUBICIN and other antibacterial drugs, CUBICIN should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria. Patients receiving CUBICIN should be observed for the development of muscle pain or weakness and have creatine phosphokinase (CPK) levels monitored weekly. CUBICIN is not indicated for the treatment of pneumonia. The most commonly reported adverse events in the cSSS infection clinical trials in adults were constipation, nausea and headache.

CUBICIN is indicated for the treatment of complicated skin and skin structure infections caused by susceptible strains of the following Gram-positive microorganisms: Staphylococcus aureus (including methicillin-resistant strains), Streptococcus pyogenes, Streptococcus agalactiae, Streptococcus dysgalactiae subsp. equisimilis and Enterococcus faecalis (vancomycin-susceptible strains only).

For full prescribing information, visit www.cubist.com.

Cubicin(TM) was previously branded Cidecin(R). Cubicin is a trademark of Cubist Pharmaceuticals, Inc.

About Cubist

Cubist Pharmaceuticals, Inc. is a biopharmaceutical company focused on the research, development and commercialization of antiinfective drugs. In the U.S., Cubist markets Cubicin(TM) (daptomycin for injection), the first antibiotic in a new class of antiinfectives, for the indication of complicated skin and skin structure infections caused by Gram-positive bacteria. Cubist's pipeline includes CAB-175, a next-generation parenteral cephalosporin antibiotic in Phase 1 trials, and an oral version of ceftriaxone (OCTX), a broad-spectrum cephalosporin antibiotic in pre-clinical development. Cubist is headquartered in Lexington, MA.

Cubist Safe Harbor Statement

Statements contained herein that are not historical fact may be forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934, and such statements are subject to a variety of risks and uncertainties. There are a number of important factors that could cause actual results to differ materially from those projected or suggested in any forward-looking statements made by Cubist. These factors include, but are not limited to: (i) the level of acceptance of CUBICIN by physicians, patients, third-party payors, and the medical community generally; (ii) Cubist's ability to continue to develop, secure additional regulatory approvals for, and successfully market, CUBICIN; (iii) Cubist's ability to manufacture CUBICIN on a commercial scale; (iv) commercialization of products that are competitive with CUBICIN; (v) Cubist's ability to further identify, develop, and achieve commercial success for new products and technologies; (vi) Cubist's ability to establish and maintain successful manufacturing, sales and marketing, distribution, and development collaborations; (vii) legislative or regulatory changes adversely affecting Cubist or the biopharmaceutical industry; (viii) Cubist's ability to protect its intellectual property and proprietary technologies; (ix) Cubist's ability to finance its operations. Additional factors that could cause actual results to differ materially from those projected or suggested in any forward-looking statements are contained in Cubist's filings with the Securities and Exchange Commission, including those factors discussed under the caption "Risk Factors" in Cubist's recent SEC filings.

SOURCE: Cubist Pharmaceuticals, Inc.

Cubist Pharmaceuticals, Inc.
Jennifer LaVin, 781-860-8362
Euro RSCG Life NRP
Financial media:
Renee Connolly, 212-845-4254
Chamberlain Communications Group, Inc.
Product media:
Jonathan Potter, 212-884-0641