Eiger BioPharmaceuticals, Inc.’s peginterferon lambda, Gilead Sciences, Inc.’s magrolimab, Takeda Pharmaceutical Co. Ltd.’s TAK-994 and Bavarian Nordic A/S’s RSV vaccine are the latest entrants to the small group of products that received breakthrough therapy designations but went on to struggle with clinical failure, changing strategic priorities, and regulatory missteps.
Breakdowns In The Breakthrough Lane: When Recipients Of FDA Expedited Designation Fall Short
Safety signals were the most common cause of discontinued candidates in the breakthrough therapy designation program in 2023.

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Organizational turmoil has not yet affected reviews of novel agent applications, with Q1 2025 approvals coming in low, but the first quarter share of the entire year is variable.
Sanofi’s Dupixent, Amgen’s Uplizna, and Bristol’s Opdivo seek new indications, while J&J hopes to start a franchise with nipocalimab and Stealth’s day of reckoning approaches.
March features nearly 20 user fee goal dates, including a crowd of novel candidates for crowded areas like hemophilia, heart disease and urinary tract infections, as well as the potentially first therapies for a rare eye disease and hyperphagia of Prader-Willi syndrome.
The US FDA approval of new meningococcal and chikungunya vaccines arrived in time for the 26-28 February meeting of the CDC’s Advisory Committee On Immunization Practices, if political developments allow.