EQRx Announces Presentation of Phase 3 Data Demonstrating a Progression-Free Survival Benefit with Sugemalimab Consolidation Therapy in Patients with Stage III NSCLC at ESMO Congress 2021

EQRx, a new type of pharmaceutical company committed to developing and delivering important new medicines to patients at radically lower prices, today announced a late-breaking mini oral presentation of data from its partner CStone Pharmaceuticals’ Phase 3 GEMSTONE-301 study at the European Society for Medical Oncology (ESMO) Congress 2021. GEMSTONE-301 is a placebo-controlled Phase 3 trial evaluating the efficacy and safety of the anti-PD-L1 antibody sugemalimab as consolidation therapy in patients with locally advanced/unresectable Stage III non-small cell lung cancer (NSCLC) without disease progression after concurrent or sequential chemoradiotherapy. GEMSTONE-301 is the first positive Phase 3 trial of a PD-(L)1 agent in this broad Stage III NSCLC patient population setting.

In May 2021, EQRx, along with its partner CStone Pharmaceuticals, announced that the GEMSTONE-301 study met its primary endpoint of prolonged progression-free survival (PFS). Detailed results of the study to be presented at ESMO 2021 on Saturday, September 18, are as follows:

• Sugemalimab, as a consolidation therapy, demonstrated statistically significant and clinically meaningful improvement in PFS vs. placebo as assessed by blinded independent central review (BICR).
  • Median PFS was 9.0 months vs. 5.8 months (HR=0.64, P=0.0026).
• Clinical benefits were observed in patients who received either concurrent or sequential chemoradiotherapy prior to sugemalimab.
  • For patients who received prior concurrent chemoradiotherapy (cCRT), median PFS was 10.5 months vs. 6.4 months (HR=0.66).
  • For patients who received prior sequential chemoradiotherapy (sCRT), median PFS was 8.1 months vs. 4.1 months (HR=0.59).
• Overall survival (OS) data were immature, but an encouraging trend for a survival benefit with sugemalimab vs. placebo was observed with follow-up of patients ongoing.
  • Median OS was not reached for sugemalimab vs. 24.1 months for placebo (HR=0.44).
• Sugemalimab had a well-tolerated safety profile and no new safety signals were observed.

“GEMSTONE-301 is a unique trial in that it enrolled a highly heterogenous population of patients with Stage III NSCLC reflective of everyday practice across a range of tumor pathologic subtypes, performance status and those treated with either sequential or concurrent chemoradiotherapy,” said Vincent Miller, MD, physician-in-chief at EQRx. “Sequential chemoradiotherapy is a widely used alternative for those who cannot tolerate or access concurrent chemoradiotherapy and there remains a high unmet need to improve outcomes for these patients. These data suggest sugemalimab may have the potential to treat a broad population of patients with Stage III NSCLC.”