The US Food and Drug Administration has dealt a significant blow to Teva and Celltrion's plans to enter the lucrative US cancer and inflammatory disease market by rejecting their biosimilar versions of two blockbuster drugs. The rejection comes after manufacturing concerns were identified at Celltrion's South Korean facility.
The regulatory setback affects the companies' biosimilar versions of Roche's Rituxan (rituximab), used for inflammatory diseases and blood cancers, and Herceptin (trastuzumab), indicated for breast and gastrointestinal cancer. Following an inspection of Celltrion's manufacturing facility, the FDA issued a warning letter citing issues including inadequate aseptic practices during batch filling and delayed responses to complaints about defective batches.
Manufacturing Concerns and Regulatory Response
The FDA's complete response letters rejecting the biosimilars stem directly from the manufacturing issues identified during the inspection. Celltrion has responded proactively to the situation, with company representatives expressing confidence in resolving these issues promptly. "Celltrion is making progress addressing the concerns raised by the FDA and is committed to working with the agency to fully resolve all outstanding issues with the highest priority and urgency," a company spokesperson stated.
European Market Progress
Despite the US setback, the companies have seen more success in Europe. Celltrion's rituximab biosimilar received European approval last year, and their Herceptin biosimilar is positioned for likely approval following a positive opinion from the European Medicines Agency's CHMP regulatory committee in February.
Impact on Business Strategy
The rejection particularly impacts Teva's business recovery plans. The Israel-based pharmaceutical company, already managing significant debt from its $40.5 billion acquisition of Allergan's generics business, had been counting on these biosimilars to strengthen its market position. The partnership between Teva and Celltrion, established in 2016, involved a $160 million upfront payment from Teva, with $60 million refundable under certain conditions.
Market Potential and Future Outlook
The US market represents a substantial opportunity, with Rituxan generating approximately $4.3 billion in sales last year, while Herceptin contributed $2.8 billion. While biosimilars typically sell at a discount compared to original drugs, they maintain higher pricing than generic medications, potentially generating significant revenue once established in the market.
Additional Concerns
The manufacturing issues also raise concerns about Teva's promising asthma drug, fremanezumab, which is produced at the same facility. This CGRP-class drug, submitted for FDA review late last year following successful phase 3 trials, is considered one of the most promising in its class by analysts.
Celltrion remains optimistic about resolving the FDA's concerns, projecting a timeline of six months for approval following resubmission. The company aims to align these resolutions with the patent expirations of Herceptin in June next year and Rituxan later this year.
