Pfizer announced on June 23 that its investigational antibody-drug conjugate, sigvotatug vedotin, did not significantly improve overall survival in a Phase 3 study of non-small cell lung cancer. The company said the trial, known as SigVie-002, focused on patients with unresectable or metastatic non-squamous non-small cell lung cancer who had received one or more prior lines of treatment.
In a statement released Monday, Pfizer said it would continue to test sigvotatug vedotin in this indication and for other solid tumors despite the lack of statistically significant results. The drug was acquired through Pfizer's $43 billion purchase of Seagen in 2023.
While specific data were not disclosed, Pfizer reported that among patients who had only one previous line of systemic therapy, there was a “stronger trend” favoring the antibody-drug conjugate over chemotherapy with docetaxel for both overall survival and progression-free survival. Leerink Partners said the subgroup analysis results are “promising,” adding that sigvotatug vedotin “still has a chance to succeed in combination with pembrolizumab”—Merck’s PD-1 inhibitor sold as Keytruda—in an ongoing first-line NSCLC study.
Pfizer confirmed it will proceed with additional studies involving sigvotatug vedotin. These include trials testing the drug alongside Keytruda and others exploring combinations such as pairing it with a PD-1/VEGF bispecific antibody. According to Pfizer, sigvotatug vedotin targets integrin beta-6 protein expressed in approximately 90% of NSCLC tumors and is designed to deliver its payload specifically to cancer cells.
Guggenheim Securities analysts said they were “disappointed but not surprised by the result given how difficult it has been for other agents to show an OS benefit over docetaxel.” In earlier commentary previewing these results, Guggenheim referenced AstraZeneca’s datopotamab deruxtecan (now called Datroway), which also failed to show significant overall survival improvement over docetaxel but later gained approval based on progression-free survival data.
