Vicuron Pharmaceuticals Inc. filed a new drug application for its lead product, anidulafungin, an antifungal agent for the treatment of esophageal candidiasis, an infection of the esophagus that commonly affects patients with compromised immune systems.
Vicuron Pharmaceuticals was formed when Versicor Inc., of King of Prussia, Pa., and Biosearch Italia SpA, of Milan, Italy, merged in a transaction valued at $225 million. The companies closed the deal three weeks ago, and as a single unit, Vicuron has 200 employees and two late-stage products. (See BioWorld Today, Aug. 1, 2002.)
Anidulafungin, in-licensed from Indianapolis-based Eli Lilly and Co. four years ago, is an echinocandins, meaning it works to kill rather than inhibit fungi, with a good safety profile, Dov Goldstein, Vicuron's chief financial officer, told BioWorld Today. Meanwhile, the Biosearch Italia acquisition consolidated the company's rights to a Phase III product, dalbavancin, an intravenous antibiotic for the treatment of serious Gram-positive infections. Data are expected on dalbavancin in the first half of 2004. (See BioWorld Today, Dec. 18, 2002.)
But Monday's news focused on the new drug application for anidulafungin, which has not received a trade name. Goldstein said Vicuron expects FDA action in 12 months.
In a statistically significant pivotal Phase III trial, intravenous anidulafungin was as effective as oral fluconazole, the current standard of care, Goldstein said. Anidulafungin was being studied to treat a fungal infection that coats the throat all the way down to the stomach, causing severe pain and sometimes anorexia.
"This was a head-to-head trial. What we showed was that these two products were equivalent products and that's important because there are certain subsets of patients with increasing resistance to fluconazole," said Goldstein, who noted the standard for approval in anti-infectives is equivalence rather than superiority.
In the pivotal trial, 97.2 percent of anidulafungin patients (242 of 249) and 98.8 percent of oral fluconazole patients (252 of 255) showed endoscopic success at the end of therapy. However, the secondary endpoint was missed. Data showed patients receiving anidulafungin demonstrated a 35.6 percent relapse rate (83 of 233), compared to 10.5 percent of fluconazole patients (24 of 229), 14 days following treatment. (See BioWorld Today, March 19, 2003.)
The company reported that esophageal candidiasis is commonly recurrent in an immunosuppressed population, as noted by the significant relapses in both arms.
Anidulafungin also was the subject of a Phase II study in invasive candidiasis. "This is important because it is a major part of the market and we feel these products have a potential to get used off label," Goldstein said. "The results for that trial were really outstanding, the best results we've seen for any antifungal, albeit, not head-to-head, so you can't say that statistically, but there were very promising results for the two high-dose groups in the 89 [percent] to 90 percent response rate."
The NDA includes safety and efficacy data from the Phase II in invasive candidiasis, as well as safety data from a Phase III studying anidulafungin in combination with a liposomal amphotericin for the treatment of invasive aspergillosis and a number of additional Phase I and Phase II clinical trials.
Vicuron has not partnered anidulafungin, believing the company can market and sell the product on its own in North America and Europe. However, Goldstein said, the company may seek a partner in Japan and Asia. Vicuron intends to file for regulatory approval in Europe by the end of 2003.
Vicuron's stock (NASDAQ:MICU) closed unchanged Monday at $11.80.