On July 27, 2015 the District Court Of Delaware stated that Glenmark’s ANDA for generic azelaic acid hydrogel infringes Bayer’s US ‘070 patent and the claims of the US ‘070 are valid. The order can be find here.
The above action was arises by the filing of ANDA by Glenmark seeking to market a generic azelaic acid hydrogel, wherein Bayer is the holder of approved New Drug Application 21470 for Finacea® Gel, 15%, indicated for topical treatment of inflammatory papules and pustules of mild to moderate rosacea.
Azelaic acid is a saturated dicarboxylic acid which is being used as topical treatments for various skin disorders, including acne vulgaris, melisma, and rosacea. FDA approved Allergan’s NDA N020428 for 20% Cream; Topical form of Azelaic acid and it is marketed under the brand name AZELEX. Further, FDA also approved Bayer’s N021470 for Finacea® Gel, 15%.
US 6,534,070 is an OB listed patent for Finacea (azelaic acid). which claims composition of azelaic acid and it is set to expire on Nov 18, 2018.
The claim of US ‘070 is
A composition that comprises:
(i) azelaic acid as a therapeutically active ingredient in a concentration of 5 to 20% by weight;
(iii) at least one triacylglyceride in a concentration of 0.5 to 5% by weight;
(iv) propylene glycol; and
(v) at least one polysorbate, in an aqueous phase that further comprises water and salts, and the composition further comprises
(ii) at least one polyacrylic acid; and
wherein the composition is in the form of a hydrogel.
About Glenmark and its ANDA:
Glenmark Pharmaceuticals is a pharmaceutical company headquartered in Mumbai, India. It manufactures and markets generic formulation products and active pharmaceutical ingredients (API), both in the domestic and international markets. In the formulation business, its business spans segments such as Dermatology, Internal Medicine, Paediatrics, Gynaecology, ENT and Diabetes.
On July 27, 2012, pursuant to 21 U.S.C. § 355(j), Glenmark submitted ANDA No. 204637, seeking approval to commercially manufacture, use, sell, offer for sale and/or import a generic Azelaic Acid Gel, 15% formulation with a paragraph IV certification stating that the ‘070 patent is not infringed and is invalid.
The ANDA product of Glenmark is a composition for topical administration to treat rosacea that contains azelaic acid as the therapeutically active ingredient and the original ANDA seems to be interchanged triglyceride and lecithin with alternate excipients to match with the reference listed drug Finacea® Gel.
Glenmark tried to develop a composition of azelaic acid which doesn’t fall with in the scope of US 070′ claims. And it further showed that the batch 540/03-08/036 (“batch 036”) and batch 540/03-08/041 (“batch 041”) were satisfactory formulations. In batch 036, PPG-20-Methyl glucose ether distearate was substituted for triglyceride and lecithin. In batch 041 – which would later become the accused formulation – isopropyl myristate was substituted for triglyceride and lecithin “to improve the penetration.
Further, Glenmark also argued that the claims of US ‘070 patent are not valid under U.S.C 103 (Obviousness), as the claims of US ‘070 are nothing but a mere optimization of the prior art formulation.
Plaintiffs (Bayer) argue that the patented composition is non-obvious and Glenmark’s ANDA infringes the claims of US ‘070.
Finally the court concluded that defendants (Glenmark) have not met their burden to prove, by clear and convincing evidence, that claims 1-12 of the ‘070 patent are invalid for obviousness and defendants infringe the asserted claims of the ‘070 patent.