A coalition of patient and provider groups sent an open letter to Leah Christl, FDA’s associate director for therapeutic biologics and biosimilars, urging FDA to use meaningful names for biosimilars instead of random ones. The letter follows the recent approval of the second U.S. biosimilar, Celltrion and Pfizer’s Inflectra (infliximab-dyyb), on April 5. Despite widespread criticism of FDA’s naming approach by innovators and biosimilar makers alike, the nonproprietary name for Inflectra uses the naming convention proposed in FDA’s August 2015 draft guidance, which combines the nonproprietary name of the innovator biologic with a random four-letter suffix “devoid of meaning.” The coalition urged FDA to return to its naming convention for the first U.S. biosimilar, Sandoz’s Zarxio (filgrastim-sndz), which combined the nonproprietary name of the innovator product, filgrastim, with a four-letter suffix “sndz” abbreviating the name of the manufacturer, Sandoz.
The letter, organized by the Alliance for Safe Biologic Medicines (ASBM), was signed by a diverse group of patient and provider organizations. Among the patient advocacy organizations signing the letter were the Lupus and Allied Diseases Association, the United Spinal association, and Gay Men’s Health Crisis. Provider organizations included the American College of Rheumatology, the American Academy of Dermatology, and the Alliance for Patient Access.
ASBM’s letter applauded FDA for creating a system of distinguishable names for biological medicines by assigning distinct four-letter suffixes to the nonproprietary names of approved reference biologics. ASBM pointed out that, unlike small molecule generics, biosimilars are not exact copies of their reference products. The letter stressed the importance of distinct names in ensuring that a patient receives the intended medication and tracking adverse events by product for purposes of pharmacovigilance and manufacturer accountability.
But the coalition criticized FDA’s decision to adopt meaningless suffixes. The letter stated that meaningful suffixes identifying the manufacturer of the biosimilar, as used for Zarxio, are easier for patients, providers and pharmacists to recognize and remember, thereby “facilitating accurate association between adverse events and specific products.” The coalition noted that a suffix based on the manufacturer’s name also promotes manufacturer accountability. ASBM also cited two surveys showing strong preference for meaningful names by healthcare professionals: (1) a survey of 400 prescribers of biologics showing that they preferred meaningful suffixes over random ones by a six-to-one margin and (2) a survey of 401 pharmacists showing that 77% prefer manufacturer-based suffixes over random ones.
Although FDA stuck to its proposal for meaningless suffixes in assigning a nonproprietary name to Inflectra despite almost universal criticism of its August 2015 draft guidance, FDA has not yet issued its final naming guidance. It remains to be seen whether FDA will change course.