The FDA issued an approvable letter for Glumetza, a once-daily, extended-release version of the diabetes drug metformin, driving up Depomed Inc.'s stock value by 11 percent.
"This is going to be a great year," Depomed Chairman, President and CEO John Fara told BioWorld Today, noting that in a few months the company expects another FDA decision on an additional product still under regulatory review.
Though Glumetza is not yet cleared for marketing, Depomed and its commercialization partner, Biovail Corp., expect to quickly address issues raised by the agency. The letter indicated that Glumetza is approvable pending discussions related to finalizing a single manufacturing specification, and Biovail plans to submit a response in the coming weeks. Fara said that Biovail, which owns the new drug application per terms of its relationship with Menlo Park, Calif.-based Depomed, has been "the chief source of communication" with the FDA.
Notably, no clinical or labeling issues were identified by the agency.
Filed almost a year ago, the new drug application was for 500-mg and 1,000-mg tablets, and the companies said that Glumetza would offer several advantages over metformin. Treatment with Glumetza can be started at 1,000 mg, while metformin initially is dosed at lower amounts to help patients avoid nausea and diarrhea before gradual increases. Also, immediate-release metformin is administered two to three times a day, whereas Glumetza's once-daily tolerability allows for faster and better control of blood sugar levels.
"Our objective was to develop a product that's conveniently dosed, with fewer gastrointestinal side effects," Fara said, adding that Glumetza was tested in two large pivotal Phase III studies. "In the trials, we looked at ways to differentiate the product further."
Both trials showed that Glumetza was not inferior to Glucophage (metformin, from Bristol-Myers Squibb Co.), demonstrating comparable efficacy between the products. The partners added that Glumetza can be paired well in combination therapy, as shown in a Phase III study with glyburide, a sulfonylurea drug often prescribed in combination with metformin for diabetes.
The 500-mg strength was developed using Depomed's Gastric Retention (GR) drug delivery technology, which encloses an ingredient in a pill that swells in the stomach to allow slow release of the medication while the pill moves through the upper intestine. Once enlarged - to about the size of a small coin - it keeps the drug out of the lower intestine to avoid gastrointestinal side effects. The 1,000-mg dose was developed using Biovail's Smartcoat delivery technology.
The approval would be Depomed's first, and would trigger a $25 million milestone payment from Biovail. The Toronto-based company also would pay royalties to Depomed on sales of Glumetza, which, if approved, would enter a $6 billion market. But in exchange for $35 million, Biovail could opt to cut its royalty rate owed Depomed, which would get a tiered royalty beginning in the high single-digits and ending in the low double-digits.
Biovail, which eventually also would assume manufacturing responsibility, has said that it expects the drug could generate sales between $800 million and $1 billion, though Fara said the market could be fragmented by generic competition. Diabetes affects an estimated 20 million Americans, and more than 150 million people worldwide. About 90 percent of diabetics suffer from Type II diabetes.
Biovail is expected to sublicense its U.S. rights to another partner in the first half of this year.
"We anticipated that this might be the case," Fara said, noting that Biovail has shifted its focus to cardiovascular areas and central nervous system indications. "The product will probably do better in another partner's hands."
Biovail expects to retain rights in Canada, where Glumetza remains under regulatory review. Elsewhere, Depomed has an agreement with LG Life Sciences in Korea for Glumetza's commercialization and distribution in that territory, and the company is in negotiations with potential partners regarding other regions.
Beyond Glumetza, Depomed's other GR system drug under FDA review is Proquin XR, a once-daily, extended-release formulation of the antibiotic ciproflaxocin to treat urinary tract infections. It is not partnered, though the company is entertaining such discussions. Fara said Depomed also is considering an internal marketing effort. Proquin XR's PDUFA date is May 19.
Two other GR drugs are in Phase II development, the diuretic Furosemide GR and the seizure and pain drug Gabapentin GR.
"It's very broad technology, and very versatile," he said. "We can deliver very soluble drugs and very insoluble drugs."
On Tuesday, Depomed's shares (NASDAQ:DEPO) gained 47 cents, or 11.5 percent, to close at $4.55.