Swiss pharmaceutical giant Roche (OTC: RHHBY) unveiled promising new data for its investigational lung cancer therapy divarasib, reporting a significant improvement in median overall survival compared to approved KRAS-targeting drugs. The results, released on October 25, 2026, from a late-stage clinical trial, showed that patients treated with divarasib lived a median of 17.7 months, versus 12.0 months for those receiving existing KRAS inhibitors, marking a 5.7-month survival benefit.
The Phase 3 study, which enrolled 338 patients across 151 centers in 26 countries, directly compared divarasib against a control group receiving either sotorasib or adagrasib, both approved KRAS G12C inhibitors. This head-to-head design provides stronger evidence than cross-trial comparisons, as it pits the newer molecular inhibitor against established therapies in a randomized setting.
However, the control arm's composition raises some caveats. Of the 171 patients in the control group, 156 (91.2%) received Amgen's sotorasib, while only 15 received Bristol Myers Squibb's adagrasib. This imbalance means the pooled comparison offers less precise insights into divarasib's performance relative to adagrasib specifically.
Key Efficacy Data
Beyond the overall survival benefit, divarasib also demonstrated superior progression-free survival (PFS). Patients on divarasib experienced a median PFS of 9.8 months versus 5.7 months for the control group, a 4.1-month improvement. The one-year PFS rate was 44% for divarasib compared to 24% for controls. The death hazard ratio stood at 0.56 (95% CI: 0.41–0.78), indicating a 44% reduction in the risk of death during follow-up, though this does not translate to a guaranteed 44% extension in life for every patient.
These findings, presented at the European Society for Medical Oncology (ESMO) congress and simultaneously published in the New England Journal of Medicine, underscore divarasib's potential as a new standard of care in this molecularly defined patient population. All participants had previously treated advanced or metastatic non-small cell lung cancer (NSCLC) harboring the KRAS G12C mutation.
Safety and Tolerability
The safety profile of divarasib appeared favorable compared to the control arm. Treatment-related grade 3 or 4 adverse events occurred in 24.6% of divarasib-treated patients versus 34.5% in the control group. Serious treatment-related events were also lower (7.8% vs. 15.2%), and fewer patients discontinued therapy due to side effects (4.8% vs. 11.7%). Median treatment duration was longer with divarasib (11.3 months vs. 5.0 months), reflecting better tolerability and disease control.
Gastrointestinal side effects were more common with divarasib, though mostly mild in severity. The lower severe-event rates do not imply fewer symptoms across all categories, but the overall tolerability profile supports its continued development.
Regulatory and Future Outlook
Roche's Chief Medical Officer Levi Garraway expressed optimism, stating, "We are working closely with health authorities to bring this new treatment option to the people who need it." The company is pursuing regulatory review, and additional Phase 3 programs—Krascendo 2 (divarasib plus pembrolizumab in untreated advanced disease) and Krascendo 3 (adjuvant setting in stage II-IIIB)—are ongoing.
Investigator Ferdinandos Skoulidis of MD Anderson, who presented the findings, noted that "divarasib significantly improved both measures compared with currently available KRAS inhibitors." However, the study's limitations include its open-label design and the small number of adagrasib patients, which may affect the precision of drug-specific comparisons. Patients with untreated brain metastases were excluded, and longer follow-up is needed to confirm the interim survival benefit.
For investors, these results could strengthen Roche's oncology pipeline and competitive positioning in the KRAS G12C space, where Amgen's Lumakras (sotorasib) and Bristol Myers Squibb's Krazati (adagrasib) are currently the only approved options. The market will watch for regulatory filings and potential label expansions, which could reshape treatment paradigms for this challenging disease.
