Merck, Daiichi Sankyo Withdraw I-DXd Application for Small Cell Lung Cancer

Merck and Daiichi Sankyo have withdrawn their request for accelerated FDA approval of ifinatamab deruxtecan, or I-DXd, for adults with extensive-stage small cell lung cancer that has worsened after platinum chemotherapy.

The companies said on September 25 that discussions with the FDA indicated the supporting data did not meet the requirements for accelerated approval.

The Phase 2 trial showed a confirmed response rate of 48.2% in patients who received the 12 mg/kg dose, with responses lasting a median of 5.3 months and an estimated 59.1% of patients alive at nine months.

However, without a control group, it is harder to know how much longer patients live because of the drug, which may explain why confirmatory data matter.

The companies will now focus on the Phase 3 IDeate-Lung02 trial, which compares I-DXd with a doctor's choice of chemotherapy in people whose cancer returned after one prior platinum-based treatment.