Axcan Pharma Inc has received an approvable letter from the U.S. Food and Drug Administration (FDA) for Photofrin in the treatment of High Grade Dysplasia associated with Barrett's Esophagus. An FDA approvable letter typically indicates that the agency intends to approve the New Drug Application (NDA). In the letter the FDA states that it has reviewed the Photofrin NDA and requests further clinical information mostly relating to 24-month follow-up data. The additional information pertaining to long-term data has been submitted to the FDA and additional information will by submitted by the end of the month. Final approval is expected to be issued in the next few months.
"This is a very important milestone for the Company and we are pleased that the approval process for Photofrin is coming to a close," commented Dr. François Martin, Senior Vice President, Scientific Affairs of Axcan. "We look forward to the approval of our product in the United States and we are excited about moving one step closer to launching this product for a condition that remains untreated and for which the only alternative is esophagectomy. In addition, long-term study results confirm that Photofrin photodynamic therapy (PDT) significantly reduces the likelihood for patients suffering from High Grade Dysplasia related to Barrett's Esophagus to see their condition progress to cancer and that Photofrin PDT can potentially be used as a means to prevent esophageal cancer," he added.
The NDA filing was based on a 208-patient study conducted in North America. 138 patients in the Photofrin PDT group and 70 patients in the comparative group were followed for a minimum 2-year period (median 3.5-year). Esophageal cancer occurred in only 13 per cent of patients treated with Photofrin PDT compared to 27 per cent of patients treated with omeprazole alone, a 52 per cent reduction that is highly statistically significant (p<0.02).
Barrett's Esophagus is a condition in which the normal lining of the lower part of the esophagus is replaced over time by another type of lining, normally present in the stomach. Barrett's Esophagus is clearly recognizable at endoscopy. Usually Barrett's Esophagus develops during the process of healing after a chronic injury to the esophageal mucosa such as caused by reflux of gastric juice in the esophagus. Continued reflux may cause dysplastic changes progressing from low-grade to high-grade dysplasia. Such dysplasia may lead to esophageal adenocarcinoma, which is a life-threatening condition.
It is estimated that 25,000 to 35,000 people are suffering from high-grade dysplasia associated with Barrett's Esophagus in North America and approximately 5,000 to 7,000 new patients are diagnosed each year. Axcan has also submitted this drug for approval in Canada and Europe and has been granted orphan drug status in both regions.