Ever since the recall of Pfizer’s smoking cessation medication, Chantix, in 2021, Par Pharmaceuticals, a subsidiary of Endo Pharmaceuticals, has been the exclusive distributor of the product. However, Par Pharmaceuticals now finds itself in a legal tussle with other generic drug manufacturers seeking entry into the Chantix market.
Endo’s Allegations Against Zydus Regarding Chantix Generic
- Legal battle involves Endo’s claims against Zydus.
- Zydus introduced generic Chantix after FDA approval in June, as stated in complaint.
- Endo alleges Zydus acted based on Endo’s new patent information.
- Patent pertains to Chantix production method without impurities from Pfizer’s formulation failure.
Chantix initially gained approval in 2006 and enjoyed significant success with peak sales reaching $1.1 billion. However, issues arising from impurities present in the product led to its decline. In September 2021, Pfizer took the decision to recall all batches of Chantix. Interestingly, the FDA had already cleared Endo’s generic version of the drug ahead of schedule, a month prior to Pfizer’s recall.
Presently, the FDA imposes strict criteria for drug submissions based on the active ingredient of Chantix, varenicline tartrate. Specifically, the drugs must adhere to acceptable limits of nitrosamine impurities. Endo succeeded in meeting this criterion, a feat that Pfizer and other companies could not achieve, as outlined in the lawsuit filed on August 8th in a Delaware federal court.
The legal claim emphasizes the intricacy involved in manufacturing varenicline tartrate tablets while maintaining the necessary minimal levels of nitrosamine. It points out Pfizer’s inability to reformulate its Chantix product to meet these standards, despite the significant motivation to do so. Endo contends that Zydus employed the methodologies described in its recent patent, as they are the sole commercially viable methods known for ensuring minimal nitrosamine impurities.
Zydus, however, chose to launch its version of the drug rather than respond to notices from Endo. This action left Endo unable to confirm whether both companies employed the same manufacturing approach. Despite the lack of verification, the complaint deems it highly probable that they share the same method.
Endo’s financial situation adds an additional layer of complexity to the case. Having declared bankruptcy in August of the previous year, Endo faced the weight of substantial settlements related to opioid litigation and a staggering $8 billion debt. The company had planned to sell itself to a group of senior lenders who would then finance the opioid settlements. However, the U.S. Department of Justice rejected this plan on the grounds that it violated bankruptcy laws by prioritizing certain creditors over others, including government entities.
