Postmarketing Safety of Biosimilars: Current Status, Challenges, and Opportunities in the Spontaneous Reporting System

Recombinant drug products successfully treat many life-threatening and chronic diseases. The high cost of these drugs makes them inaccessible to the patients particularly in developing countries. Patent expiration of innovator recombinant drug products has led to the development of biosimilars or similar biologics by several manufacturers. Unlike generics, these are not identical to their innovator products because of the differences in the manufacturing process; however, they are similar in quality characteristics, biological activity, safety, and efficacy. The regulatory procedures used for generic drugs cannot be applied for biosimilars as they are large complex structures produced from living cells and can produce potential risk of immune-based adverse reactions. Out of several safety issues related to biosimilars, two main safety concerns are variable potency and immunogenicity, for which a robust long-term pharmacovigilance system is needed. Various guidelines have been issued for the regulatory approval and pharmacovigilance of biosimilars by USFDA, EU, and pharma-emerging countries like China and India. The article includes the pharmacovigilance plan of biosimilars in these countries, discusses the challenges and opportunities in pharmacovigilance through spontaneous reporting systems, and suggests amendments in the existing suspected adverse event reporting form of the Pharmacovigilance Programme of India.