Tambotatug Pelitecan: Interim Survival Benefit in Relapsed SCLC

September 14, 2026 at 12:30

Tambotatug pelitecan (Tam-Peli) significantly improved overall survival compared with topotecan in Chinese patients with relapsed small-cell lung cancer (SCLC), according to interim results from the phase 3 TAISHAN-302 trial announced by Roche. The investigational antibody-drug conjugate targets B7-H3 and carries a topoisomerase 1 inhibitor payload.

The randomized, open-label trial enrolled 451 patients at 85 sites in China whose disease progressed after one prior line of platinum-based chemotherapy, with or without a PD-L1 inhibitor. Patients were assigned to tambotatug pelitecan (225 patients) or topotecan (226 patients). Tambotatug pelitecan was administered intravenously at 2.0mg/kg on day 1 of each 21-day cycle, capped at 200mg. Overall survival was the primary endpoint.

Median overall survival was 13.3 months with tambotatug pelitecan versus 9.4 months with topotecan (stratified hazard ratio, 0.46; 95% CI, 0.35–0.62). Investigator-assessed median progression-free survival (PFS) was 7.4 versus 2.8 months, and confirmed objective response rates were 59.1% versus 9.7%. Among patients with baseline brain metastases, median intracranial PFS was 6.1 versus 4.2 months, with intracranial response rates of 32.4% versus 2.9%.

Grade ≥3 treatment-related adverse events occurred in 46.4% of patients receiving tambotatug pelitecan versus 74.7% receiving topotecan; serious treatment-related events occurred in 25.9% versus 36.4%. Any-grade treatment-emergent interstitial lung disease/pneumonitis occurred in 4.9% versus 1.4%. Grade 3 interstitial lung disease/pneumonitis occurred in 0.9% of each group, with no grade 4 or 5 cases reported.

According to Roche, the results were presented at the 2026 World Conference on Lung Cancer in Seoul with simultaneous publication in NEJM. The release states that the FDA granted Breakthrough Therapy designation for relapsed SCLC and that China’s drug regulator accepted the new drug application for filing. Tambotatug pelitecan remains investigational; Roche plans global phase 3 trials in its licensed territories outside mainland China, Hong Kong, and Macau.