Including Zymfentra, Which Is Sold As A New Drug And Not Biosimilar As the US pharma tariff drama reached its culmination, Celltrion aims to lock down its domestic manufacturing capabilities as a future-proof strategy. Meanwhile, the Korean firm expands biosimilar prescription bases in the US and Europe. (Shutterstock) Key Takeaways Celltrion said the latest announcement on US pharma tariffs has resolved any lingering uncertainties on the potential business impact.