Bristol Myers Squibb's targeted AML drug Idhifa fails to extend patients' lives

Back in 2017, the FDA cleared Celgene's acute myeloid leukemia therapy Idhifa based on complete remission data. But fast forward to today, and the drug has chalked up a clinical failure that shows it doesn't actually extend lives.

Idhifa, which bears an FDA nod in relapsed or refractory AML with an IDH2 mutation, failed to show it could improve survival within that same patient population when used alongside best supportive care in a late-stage study, new owner Bristol Myers Squibb said Tuesday.

The phase 3 Idhentify trial flop doesn’t affect Idhifa’s original green light, though; that's a full approval not reliant on any confirmatory studies.

Idhifa is the only FDA-approved therapy for previously treated patients with IDH2-mutated AML, which according to BMS make up 19% of all AML cases. Before it snagged an FDA nod, conventional treatment options for these patients included best supportive care, or a combination of best supportive care and either Celgene’s Vidaza (azacitidine) or cytarabine.

Previously, in a single-arm study of 199 patients, 19% of patients experienced no signs of disease and full blood-count recovery for a median 8.2 months after treatment with Idhifa. The drug also helped some patients avoid transfusions of blood or platelets.

Still, Celgene—now part of BMS after a 2019 megamerger—launched the phase 3 Idhentify trial in hopes of showing an overall survival benefit, which is considered the gold standard for evaluating cancer drugs. But things didn’t play out as the company had planned, and Bristol said it would complete a full evaluation of the data and present them at a future medical meeting.

AML in general is an increasingly competitive field. Agios, which partners with Celgene on Idhifa, also has Tibsovo for previously treated AML patients with an IDH1 mutation, and the Massachusetts biotech recently sold its sales-based royalty rights to Idhifa to Royalty Pharma for $255 million. Both Tibsovo and Idhifa are being evaluated alongside azacitidine in newly diagnosed AML.

RELATED: EHA: AbbVie, Roche cement Venclexta's place in AML with survival win

AbbVie and Roche, meanwhile, recently showed that adding their Venclexta to azacitidine cut the risk of death by 34% in previously untreated patients. Celgene and AbbVie are marked as collaborators in an investigator-sponsored phase 1b/2 trial combining Venclexta with Idhifa in previously treated IDH2-mutated AML.

Astellas, for its part, markets Xospata in previously treated AML with an FLT3 mutation. That drug also showed it can significantly prolong the lives of those patients.

Bristol Myers Squibb, through its Celgene acquisition, boasts a strong portfolio in blood cancers, led by Revlimid, which brought in $5.8 billion in sales in the first six months of 2020. The New York pharma didn’t specify Idhifa sales figures in its half-year securities filing.