Patent Suit Alleges MSN Laboratories Skipped Royalties on Generic Drug

On Thursday a complaint was filed in the District of Delaware. The case, filed by Amgen Inc. and Kai Pharmaceuticals, Inc. against MSN Laboratories, regarding possible violation of 6 patents owned by or assigned to the plaintiffs. Specifically, the case alleges that MSN Laboratories seeks to introduce a competing generic product without paying royalties regarding the patents.

The patents concern the treatment of secondary hyperparathyroidism in adult patients with chronic kidney disease on hemodialysis causing hypercalcemia. Specifically, the patents concern the creation of Parsabiv, which activates cells to notice the extra calcium in the bloodstream and causing the body to decrease the amount of parathyroid hormone that is created. This especially improves the fatigue and muscle pain associated with this condition.

MSN Laboratories has filed an ANDA Notice letter with the FDA and with Amgen regarding the creation of a generic version of Parabiv for the domestic market. Review of the notice and of the proposed packaging that has been submitted by MSN Laboratories has lead the plaintiffs to note claims and product specifications that directly violate the patents. The plaintiffs are suing for infringement of each of the 6 patents and seeking for the effective date for approval of the generic to be delayed until the expiration of the patents, as well as seeking an injunction regarding the manufacture or sale of the generic. The plaintiffs are represented by Jack B. Blumenfeld and Karen Jacobs of Morris, Nichols, Arsht & Tunnell.