Megestrol acetate NCD oral suspension--Par Pharmaceutical: megestrol acetate nanocrystal dispersion oral suspension, PAR 100.2, PAR-100.2

Abstract

Par Pharmaceutical has developed megestrol acetate (Megace ES) oral suspension for the treatment of anorexia, cachexia and a significant weight loss associated with AIDS. Par Pharmaceutical used Elan Corporation's NanoCrystal Dispersion (NCD) technology to develop an advanced, concentrated formulation of megestrol acetate with improved bioavailability, more rapid onset of action, more convenient dosing and a lower dosing regimen compared with the original marketed formulation of megestrol acetate oral suspension. Patients are administered a teaspoon (5mL) of the new NCD formulation once daily, compared with a daily 20mL dosage cup of the original formulation. The new megestrol acetate NCD formulation represents a line-extension of Par's megestrol acetate oral suspension (800mg/20mL, Megace O/S) that has been marketed for anorexia, cachexia and AIDS-related weight loss since July 2001. Par's megestrol acetate is the generic version of Bristol-Myers Squibb's Megace Oral Suspension. NanoCrystal Dispersion (NCD) is a trademark of Elan Corporation. Par Pharmaceutical will market megestol acetate NCD oral suspension under the Megace brand name. The company licensed the Megace name from Bristol-Myers Squib in August 2003. The US FDA approved megestrol acetate oral suspension (625 mg/mL) in July 2005 for the treatment of anorexia, cachexia or a significant, unexplained weight loss in patients with AIDS. The NDA for the product was accepted for review by the agency in September 2004, following its submission in June of that year.Par Pharmaceutical commenced the first of two phase III clinical trials of megestrol acetate oral suspension (PAR 100.2) in cancer-induced anorexia in the first quarter of 2006. However, this trial was discontinued in September 2006 because of slow patient enrolment. The company intends to discuss future development options in this indication with the FDA.New formulations or dosage forms of megestrol acetate concentrated suspension are also in development; Par Pharmaceutical believes these may be available sometime after 2008. The US Patent and Trademark office issued Patent No. 7 101 576 to Elan Pharma International, relating to megestrol acetate 625mg/5mL oral suspension, in September 2006. The patent covers more than 30 additional claims in connection with Par Pharmaceutical's novel formulation of megestrol acetate, and includes claims relating to the advanced formulation of megestrol acetate, specifically to the reduction of the food effect seen with previous formulations of megestrol acetate. The patent expires on 22 April 2024. In August 2003, Teva USA filed a lawsuit again Par Pharmaceutical in the US District Court for the District of Delaware after receiving approval to launch in the US a generic version of Bristol-Myers Squibb's Megace. In the lawsuit, Teva declared that its product did not infringe any of Par's four patents related to megestrol acetate oral suspension. In the countersuit filed in August 2003, Par stated that Teva willfully infringed one of Par's four patents in the lawsuit, US patent No. 6,593,318. Both companies settled the lawsuit in July 2004 with Par granting a licence to Teva USA for a limited number of units and Par receiving royalties on Teva USA's net sales of megestrol acetate oral suspension.