Data Suggest Optimer's DIFICID® Provides Economic Value in the Treatment of Clostridium difficile-associated Diarrhea

SAN DIEGO, Dec. 6, 2011 /PRNewswire/ -- Optimer Pharmaceuticals, Inc. (Nasdaq: OPTR) announced today that data being presented at the American Society of Health-System Pharmacists 46th Midyear Clinical Meeting demonstrate that the economic value of DIFICID® (fidaxomicin) tablets to the U.S. health system meets or exceeds the price per day to treat Clostridium difficile-associated diarrhea (CDAD) compared to vancomycin. Results showed that when data accounting for the cost and frequency of disease recurrence are factored into an economic equation weighing the value of DIFICID against three common regimens of vancomycin, the overall value provided by DIFICID, which ranged from 95% to 141% of the drug's wholesale acquisition cost (WAC), indicates it is cost saving in many treatment scenarios.

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"Clostridium difficile is the most common cause of infectious diarrhea in hospitalized patients in North America and Europe, and the incidence and severity of the disease have increased significantly over the past decade," said Dr. David A. Sclar, Boeing Distinguished Professor of Health Policy and Administration, Washington State University. "Fidaxomicin represents an advance in the treatment of CDAD. Our results indicate that from the perspective of the U.S. health system, use of fidaxomicin is financially prudent."

Study Results 

When accounting for a real-world mix of primary and secondary cases of CDAD in hospital and outpatient settings, the researchers found that compared to the cost of 125 mg injectable vancomycin administered orally four times daily, the daily price of DIFICID was warranted at 95% of the current wholesale acquisition cost (WAC).  When compared to more costly doses of branded vancomycin capsules, DIFICID provided a value of 111% (vs. vancomycin capsules 125 mg) and 141% (vs. vancomycin capsules 250 mg).

"The results of the analysis presented at ASHP suggest that, in addition to the clinical benefits that were demonstrated in two large, Phase 3 clinical studies, DIFICID can provide substantial economic benefits to the U.S. health system," said Hemal Shah, PharmD, Senior Vice President, Health Economics & Outcome Research (HEOR) and New Products Marketing, Optimer Pharmaceuticals. "We are especially encouraged by the data demonstrating that among a real-world case mix of patients with varying severity of CDAD and risk of recurrence, DIFICID exceeded the value currently being provided by two commonly used regimens of vancomycin and approached parity with the drug even when compared to vancomycin slurry."

About the Study

Study results were derived from a novel epidemiological model developed by researchers at Washington State University to determine the value of DIFICID in a real-world clinical setting based on the benefit the drug provides in producing sustained clinical response. In two large Phase 3 clinical studies, patients treated with DIFICID 200 mg administered twice daily had clinical response rates at the end of the 10-day treatment period that were non-inferior to oral vancomycin capsules 125 mg administered four times daily. In addition, DIFICID was superior to vancomycin in sustained clinical response, defined as clinical response at the end of treatment and survival without proven or suspected CDAD recurrence through 25 days beyond the end of treatment. This difference was due to lower rates of proven or suspected CDAD during the follow-up period in DIFICID-treated patients.

Based on the sustained clinical response rates for DIFICID, researchers determined that one CDAD patient would be spared a disease recurrence for every seven patients treated with DIFICID in the first-line setting (researchers called this the number needed to treat, or NNT). Disease recurrence is costly in both the outpatient and hospital settings, with average hospital costs exceeding $10,000 for primary cases, and approximately $14,000 for secondary cases.

Using the NNT as a baseline combined with aggregated data from the U.S. Healthcare Cost and Utilization Project (HCUP) on the incidence, cost and hospital mean length of stay (LOS) for primary and secondary cases of CDAD (i.e. the condition primarily responsible for the patient's admission to the hospital or conditions that coexist at the time of admission or that develop during the stay), the researchers built an equation to determine the warranted price of DIFICID per day, 200 mg twice daily,  compared to the cost of three regimens of vancomycin: injectable vancomycin used orally, 125 mg four times daily; vancomycin HCL capsules, 125 mg four times daily; and vancomycin HCL capsules, 250 mg four times daily for a 10-day course of therapy. The method for attribution of hospital LOS for secondary cases of CDAD was derived from a study by O'Brien, et al (2007).  The three comparative regimens were injectable vancomycin administered orally during hospitalization (7 days for primary and 3 days for secondary cases) followed by vancomycin 125 mg capsules after hospital discharge, or the respective doses of vancomycin 125 mg or 250 mg capsules for the entire course of therapy. The warranted price for the U.S. health system (which combined inpatient hospital use with outpatient use) was expressed as the percentage of WAC compared against the three vancomycin regimens.

The study was sponsored and funded by Optimer Pharmaceuticals.

About CDAD

Clostridium difficile-associated diarrhea (CDAD) has become a significant medical problem in hospitals, long-term care facilities and in the community. CDAD is a serious illness resulting from infection of the inner lining of the colon by C. difficile bacteria, which produce toxins that cause inflammation of the colon, severe diarrhea and, in the most serious cases, death. Patients typically develop CDAD from the use of broad-spectrum antibiotics that disrupt normal gastrointestinal (gut) flora, possibly allowing C. difficile bacteria to flourish. Older patients in particular are at risk for CDAD, potentially because of a weakened immune system or the presence of underlying disease. Approximately two-thirds of CDAD patients are 65 years of age or older. Historically, approximately 20% to 30% of CDAD patients who initially respond to treatment experience a clinical recurrence.

About DIFICID® (fidaxomicin) Tablets

DIFICID is the first antibacterial drug indicated for CDAD to be approved in more than 25 years. It is indicated for the treatment of CDAD in adults 18 years of age or older. DIFICID is administered in 200 mg tablets given orally twice daily.

Important Safety Information about DIFICID

DIFICID should not be used for systemic infections. Only use DIFICID for infection proven or strongly suspected to be caused by C. difficile. Prescribing DIFICID in the absence of a proven or strongly suspected C. difficile infection is unlikely to provide benefit to the patient and increases the risk of the development of drug resistant bacteria. The most common adverse reactions are nausea (11%), vomiting (7%), abdominal pain (6%), gastrointestinal hemorrhage (4%), anemia (2%) and neutropenia (2%).

For full prescribing information for DIFICID, please call 1-855-DIFICID (1-855-343-4243) or visit www.DIFICID.com.

About Optimer Pharmaceuticals

Optimer Pharmaceuticals, Inc. is a global biopharmaceutical company focused on discovering, developing and commercializing innovative hospital specialty products that have a positive impact on society. Optimer has developed and is commercializing DIFICID® (fidaxomicin) tablets, an FDA-approved antibacterial drug for the treatment of adult patients with Clostridium difficile-associated diarrhea (CDAD). Optimer is seeking marketing authorization for fidaxomicin in the European Union and Canada and is exploring marketing authorization in other parts of the world where C. difficile has emerged as a serious health problem, including Asia. Additional information can be found at http://www.optimerpharma.com.

Forward Looking Statements

Statements included in this press release that are not a description of historical facts are forward-looking statements, including without limitation statements related to the ability of DIFICID to provide economic benefits to the U.S. health system compared to other therapies and the incidence and costs of CDAD. Words such as "believes", "would", "anticipates", "plans", "expects", "may", "intend", "will", and similar expressions are intended to identify forward-looking statements. The inclusion of forward-looking statements should not be regarded as a representation by Optimer that any of its plans will be achieved. These forward-looking statements are based on management's expectations on the date of this release. Actual results may differ materially from those set forth in this release due to the risks and uncertainties inherent in Optimer's business including, without limitation, risks relating to: whether healthcare professionals will prescribe DIFICID, the extent to which DIFICID will be accepted on hospital formularies, the development of alternative means of preventing or treating CDAD, the future pricing of competitive treatments for CDAD and other risks detailed in Optimer's filings with the Securities and Exchange Commission.  Forward-looking statements speak only as of the date of this release, and Optimer undertakes no obligation to update or revise these statements, except as may be required by law.

Contacts

Optimer Pharmaceuticals, Inc.
David Walsey, Vice President, Investor Relations and Corporate Communications
858-909-0736

Canale Communications, Inc.
Jason I. Spark, Senior Vice President
619-849-6005

SOURCE Optimer Pharmaceuticals, Inc.