Exelixis: STELLAR-303 NLM OS endpoint not statistically significant

The final NLM-subgroup OS analysis showed a non-significant trend favoring zanzalintinib + atezolizumab (HR 0.83, P=0.1185). The ITT population had already met its dual-primary OS endpoint with statistical significance. The NDA for the combination remains under FDA review with a December 3, 2026 PDUFA date.

Key facts

Filed: Jun 22, 2026, 12:00 PM
Event: Topline results
Direction: Neutral
Company: EXELExelixis
Asset: zanzalintinib
Source: Company press release
Confidence: Sourced
Calendar: FDA decision (PDUFA) · Dec 3, 2026 · Positive
95 CI: 0.66–1.05
p value: 0.1185
stratified HR: 0.83
median OS regorafenib: 12.7 months
median OS zanza atezo: 15.9 months

Source excerpt

Exelixis Provides Update on the Phase 3 STELLAR-303 Trial Evaluating Zanzalintinib in Combination with an Immune Checkpoint Inhibitor in Patients with Metastatic Colorectal Cancer Exelixis Provides Update on the Phase 3 STELLAR-303 Trial Evaluating Zanzalintinib in Combination with an Immune Checkpoint Inhibitor in Patients with Metastatic Colorectal Cancer Exelixis Provides Update on the Phase 3 STELLAR-303 Trial Evaluating Zanzalintinib in Combination with an Immune Checkpoint Inhibitor in Patients with Metastatic Colorectal Cancer Exelixis, Inc. (Nasdaq: EXEL) today announced results from the final analysis of the dual primary endpoint of overall survival (OS) in the subset of patients without active liver metastases (non-liver metastases, NLM) in the phase 3 STELLAR-303 pivotal trial evaluating zanzalintinib in combination with atezolizumab (Tecentriq ® ) versus regorafenib in previously treated non-microsatellite instability (MSI)-high metastatic colorectal cancer (mCRC). The results showed a non-statistically significant trend in OS favoring the combination in the NLM subpopulation (stratified hazard ratio: 0.83; 95% confidence interval: 0.66–1.05; P=0.1185), with median OS values of 15.9 months with zanzalintinib in combination with atezolizumab, and 12.7 months with regorafenib. The safety profile of zanzalintinib in combination with atezolizumab in the NLM subgroup was consistent with that previously reported in the intention-to-treat (ITT) population, and no

Company press release