FDA Center for Drug Evaluation and Research

Federal agency responsible for protecting public health by ensuring safety and efficacy of drugs and biologics. - Reversed position on ALLELE trial adequacy, requesting new study despite no safety concerns

The FDA rejected tabelecleucel for the second time on January 9, 2026—one day before its scheduled approval decision. The agency reversed its position after five years of dialogue, now claiming the previously accepted ALLELE trial no longer provides sufficient evidence of efficacy due to problems with study design, conduct, and analysis. The companies resolved all manufacturing issues and the FDA raised no safety concerns, but regulators demanded a new study for the first therapy targeting EBV+ post-transplant lymphoproliferative disease.

Updated Jan 13

The gatekeeper for new drug approvals, currently scrutinizing BTK inhibitor liver toxicity. - Reviewing BTK inhibitor safety across multiple programs

The FDA just rejected Sanofi's tolebrutinib for progressive multiple sclerosis on December 28, 2025—a crushing blow for a drug that had won Breakthrough Therapy status and became the first BTK inhibitor approved anywhere in the world. Meanwhile, Roche's rival drug fenebrutinib is racing toward approval after stunning Phase 3 victories, and Merck's evobrutinib crashed out entirely. Three pharma giants bet billions that brain-penetrating BTK inhibitors could finally slow the relentless neurodegeneration that leaves MS patients in wheelchairs. Only one looks likely to reach the finish line first.

Updated Dec 28, 2025