Metformin extended release [Glumetza, metformin hydrochloride, metformin gastric retention, metformin GR] is a proprietary once-a-day formulation of metformin hydrochloride under development with Depomed for the treatment of diabetes mellitus. In May 2002, Depomed licensed manufacturing and marketing rights for its proprietary formulation of metformin extended release (500mg dose) to Biovail Corporation for the US (including Puerto Rico) and Canada. Under the terms of the agreement, Biovail will pay DepoMed a 25 million dollars milestone fee upon approval of the 500mg dosage and also customary royalties on the net sales in the US and Canada. Biovail also agreed to acquire approximately 2.4 million of additionally issued Depomed shares for 12.3 million dollars. Biovail has subsequently developed a 1000mg dose of metformin extended release [metformin XR] using its proprietary Smartcoat delivery technology allowing a graduated release of the active drug from the tablet. In April 2004, Depomed and Biovail amended their original license agreement of May 2002. Under the terms of the amended agreement, Depomed will receive royalties on sales of Biovail's 1000mg tablet in the US and Canada. In turn, Biovail acquired access to Depomed's clinical data for the metformin 500mg tablet that will be used to accelerate regulatory filings for Biovail's 1000mg tablet and establish equivalence between the two dosages. Biovail is seeking marketing partners for metformin extended release (Glumetza) in the US. The company anticipates signing an agreement for the US during the second half of 2005. In Canada, Biovail Corporation will market Glumetzatrade mark through its Canadian division, Bioval Pharmaceuticals Canada. Depomed has an agreement with LG Life Sciences for the commercialisation and distribution of metformin extended release in Korea. Metformin GR is available for partnership in Europe and Asia. Biovail Corporation and Depomed announced in June 2005 that the US FDA has approved metformin extended release (Glumetza) 500mg and 1000mg tablets for the treatment of type 2 diabetes mellitus. Biovail plans launching the product in the fourth quarter of 2005. In July 2005, Biovail paid Depomed a 25 million dollars milestone payment following approval of metformin extended release in the US for type 2 diabetes. In March 2005, Biovail Corporation and Depomed announced that they have received an approvable letter from the FDA for the once-daily, extended-release formulation of metformin extended release (Glumetza) 500mg and 1000mg tablets. The letter specified an issue related to finalising one manufacturing specification. There were no clinical labeling issues identified in the letter. Both companies filed a response to a specified issue at the FDA on 8 April 2005. The companies believed that the response will be classified as a Class I response with a 60-day review period. The 500mg dosage was developed by Depomed using its patented drug delivery GR technology, while Biovail developed metformin 1000mg dose using its proprietary Smartcoat delivery technology. Biovail's NDA for a once-daily, extended-release formulation of metformin HCl for the treatment of type II diabetes was filed in April 2004 and accepted for review in June 2004 by the FDA. Depomed completed two double-blind, pivotal, phase III clinical trials with metformin extended release 500mg at 60 sites in the US in more than 1000 patients with type 2 diabetes. In three different dosing regimens, metformin extended release significantly decreased the glycosylated haemoglobin level similarly to that of metformin immediate-release. Biovail successfully compared metformin extended release 1000mg dose with Depomed's 500mg dose in multiple equivalence studies. In these studies, metformin extended release was well tolerated and demonstrated an excellent safety profile in terms of gastrointestinal adverse events. On 1 June 2005, Depomed and Biovail Comporation, the licensee, announced that the Therapeutic Products Directorate in Canada issued a Notice of Compliance for metformin extended release (Glumetza) 500mg and 1000mg for the treatment of type 2 diabetes. Biovail Pharmaceuticals Canada plans to launch the product in the fourth quarter of 2005. Biovail has submitted an application for metformin extended release with the Therapeutic Products Directorate in Canada. and received notification of acceptance for review in August 2004. Bristol-Myers Squibb is marketing a proprietary, once-daily extended-release formulation of metformin (Glucophage XR). Several companies are developing controlled-release and extended-release formulations of metformin.