Summary
The FDA has fully approved the drug tarlatamab (Imdelltra) for small-cell lung cancer, after a trial showed it reduces death risk by ~40% compared with chemo.
On November 19, 2025, the U.S. Food and Drug Administration (FDA) gave full approval to the drug tarlatamab (brand name Imdelltra) for adults with advanced small cell lung cancer (SCLC) that returned after platinum-based chemotherapy.
This decision came after a global phase 3 study led by researcher Charles M. Rudin from Memorial Sloan Kettering Cancer Center (MSK). The trial included 509 patients whose cancer had come back. Each participant was randomly assigned to receive either tarlatamab or standard chemotherapy.
People treated with tarlatamab lived longer. The drug reduced the risk of death by about 40% compared to chemotherapy. Even patients whose cancer had spread to the brain, which is usually a sign of aggressive disease, benefited from tarlamatab.
Also, tarlatamab caused fewer severe side effects. Less than one-fifth of people on tarlatamab had to stop or lower their dose because of side effects, while more than half of those on chemotherapy did. Patients receiving tarlatamab also reported fewer symptoms like cough and trouble breathing compared with chemo.
Tarlatamab belongs to a group of medicines called bispecific T-cell engagers (BiTE). It connects a patient’s immune cells with cancer cells so the immune cells can attack the cancer directly.
The full FDA approval of tarlatamab offers a new, more effective and gentler treatment option for many people with relapsed small-cell lung cancer.
