DIFICID^® (Fidaxomicin) Approved by Taiwan Department of Health for the Treatment of Clostridium Difficile Associated Diarrhea (CDAD)

TAIPEI, 20 July 2012
OBI Pharma, Inc. announced today that DIFICID^® (Fidaxomicin) has been approved by Taiwan’s Department of Health for the treatment of Clostridium Difficile Associated Diarrhea (CDAD). DIFICID^® is the first drug to be approved for the treatment of CDAD in Taiwan.

DIFICID^® was developed by Optimer Pharmaceuticals, Inc. Two large multicenter and multinational Phase 3 clinical trials have shown DIFICID^® to be as effective as Vancomycin at the initial clinical response and was superior in providing a sustained cure for 28 days post-treatment.

The new drug application of DIFICID^® received unanimous (13:0) approval by the US FDA in April 2011. It was approved by EMEA for the EU market in December 2011 and, subsequently, was approved by Health Canada earlier this month. In Taiwan, DIFICID^® gained priority review status by the Taiwan Food and Drug Administration in June 2011, which was followed by an exemption for a bridging clinical study in November 2011. OBI Pharma, Inc. received the Approval Letter on 20 July 2012. DIFICID^® will be available for CDAD patients in Taiwan after the grant of a Drug License, which is expected in August 2012.

Clostridium Difficile Associated Diarrhea (CDAD)
The infection and overgrowth caused by Clostridium Difficile leads to CDAD. Common venues of occurrence include hospitals, care centers, and communities. A significant increase of CDAD incidences has been observed in North America and the EU in recent years, raising concerns in those respective healthcare communities. The US Centers for Disease Control reported in March that the number of CDAD cases increased rapidly from 139,000 to 336,600 from 2000 to 2009. A hospital-acquired infection episode in Canada was known to have taken 89 lives. Since 2005, several CDAD outbreaks happened in EU countries, including the UK, France, Belgium, and the Netherlands. To contain the situation, health authorities across the EU and North America announced specific measures to monitor and strengthen the control of this disease.

CDAD is an intestine infection where the toxins generated by the Clostridium difficile bacterium lead to clinical symptoms, including pseudomembranous colitis, profuse watery diarrhea, and bowel perforation, including, egregious cases, death. In Taiwan, there is no antibiotic available that target the sporulation of Clostridium Difficile resulting in repeated the recurrence of CDAD. Moreover, because the use of broad spectrum antibiotics alters the intestinal micro flora, many caution on the outgrowth of Clostridium Difficile, especially in immune-compromised patients.

The common therapy for CDAD in Taiwan is off-label use of Metronidazole and the only FDA-approved treatment option is Vancomycin tablet. Both Metronidazole and Vancomycin are broad spectrum antibiotics which involve the common disadvantage of significant alteration of the normal gut flora, as well as increasing drug resistance in the general human population. On average, 25-30% of patients experience a recurrence of CDAD post-treatment. This recurrence rate is especially high in certain patient risk groups, including the elderly, cancer chemotherapy patients, long-term hospitalization, frequent exposure to antimicrobial agents, among others. An outbreak of CDAD has not been observed in Taiwan. However, an increasing trend of CDAD cases has been noticed. The increased incidence and the high recurrence rate of current treatment options has raised great concerns among healthcare professionals in Taiwan. The soon-to-be available DIFICID^® will bring a new solution to CDAD treatment.

DIFICID^® (Fidaxomicin)

DIFICID^® is a first-in-class macrocyclic, narrow spectrum antibiotic. It inhibits the RNA polymerase of Clostridium Difficile and kills the bacterium. This unique narrow-spectrum antibiotic selectively eliminates Clostridium Difficile and reduces the alteration of gut flora to the minimum. DIFICID^® is not absorbed into the system and is subsequently excreted directly to the feces. Therefore, it achieves high intestinal concentrations and has a great safety profile. In addition, DIFICID^® is the only antibiotic demonstrated to have effective inhibition and new spore formulation. This novel mechanism is suggested to contribute to an improved, sustained cure with DIFICID^® . Two large scale clinical studies have demonstrated that the recurrence rate of 28 days post-DIFICID^® treatment was reduced to nearly 50% of that of Vancomycin. The sustained cure (no recurrence 28 days post-treatment) was also significantly better than that of Vancomycin.