Sigvotatug Vedotin Misses OS Endpoint

Sigvotatug vedotin did not show a statistically significant improvement in overall survival (OS) versus docetaxel in the overall population of the Phase 3 SigVie-002 study (NCT06012435). - - Safety was “manageable” and consistent with prior studies. - - In patients who received only one prior line of systemic therapy (two-thirds of the study population), a stronger trend was observed for OS and progression-free survival (PFS) for sigvotatug vedotin over docetaxel. - - Exploratory analysis found no clear IB6 expression-response relationship. - - Detailed SigVie-002 results will be submitted for presentation at a future medical congress. - - SigVie-002 enrolled 703 participants; patients received sigvotatug vedotin IV on Days 1 and 15 of a 28-day cycle or docetaxel IV on Day 1 of each 21-day cycle. - - Note: The second-line signal is explicitly a subgroup trend in roughly two-thirds of the trial, but Pfizer gives no HR, p-value, median OS, or multiplicity protection, leaving the ongoing first-line pembrolizumab combo as the real salvage path rather than a clear registrational rescue.

The open-label design makes blinded central PFS less vulnerable, but the primary OS miss against docetaxel raises the bar for proving the ADC adds clinically meaningful benefit when moved earlier and layered onto immunotherapy.