FDA cuts IMDELLTRA first-dose monitoring window to 6 to 8 hours from 22 to 24 hours

The FDA approved a label update on September 14, 2026 that shortens the observation period after the first two IMDELLTRA infusions to 6 to 8 hours, down from 22 to 24 hours. The change covers adults with extensive-stage small cell lung cancer whose disease progressed on or after platinum-based chemotherapy. Amgen says the shorter window reduces time in clinic and simplifies treatment for community oncology practices.

• Previous monitoring window: 22 to 24 hours after the first two doses
• New monitoring window: 6 to 8 hours from the start of the first two infusions
• Covers Cycle 1 Day 1 and Cycle 1 Day 8 doses
• Monitoring for later doses is not changed