Dificid (fidaxomicin tablets; Optimer), a macrolide antibiotic, has been approved for the treatment of Clostridium difficile-associated diarrhea (CDAD) in patients ≥18 years old. This approval was based on data from two Phase 3, randomized, multicenter trials that compared Dificid (200mg orally twice daily for 10 days) with vancomycin (125mg orally four times daily for 10 days) in 1,164 patients with CDAD.

The clinical response was similar in the Dificid group compared with the vancomycin group in both studies. In the first trial, 88% of patients who received Dificid experienced a clinical response at the end of therapy (n=289) compared to 86% of vancomycin-treated patients (n=307) [95% CI]. Results for clinical response at the end of therapy were consistent in the second trial, 88% clinical response rate in Dificid-treated patients (n=253) compared to an 87% response rate in vancomycin-treated patients (n=256) [95% CI]. Additionally, sustained clinical response 25 days after the end of treatment was 70% for Dificid-treated patients in the first trial and 72% for Dificid-treated patients in the second trial [95% CI], compared to 57% in both trials for vancomycin-treated patients [95% CI].

Dificid will be available in July 2011 in a 200mg dosage strength tablet.

For more information call (855) DIFICID or visit www.dificid.com.