Relay Therapeutics (RLAY) investor relations material

Key clinical program updates

• Zovegalisib demonstrated 11 months PFS in second-line HR+/HER2- breast cancer, outperforming current standards like capivasertib and alpelisib, with improved tolerability and lower toxicity rates.

• A pivotal global phase III trial is underway, comparing zovegalisib plus fulvestrant to capivasertib plus fulvestrant, with enrollment progressing well and updates on full enrollment expected by year-end.

• In first-line HR+/HER2- breast cancer, a triplet regimen of zovegalisib, atirmociclib, and endocrine therapy is being advanced, aiming for broad tolerability and efficacy in PIK3CA-mutant patients; phase III is planned for early 2027.

• Vascular anomalies data showed a 60% volumetric response rate, significantly higher than alpelisib, with better tolerability; dose expansion and regulatory updates are expected by year-end.

• The NRAS program (RLY-8161) entered clinical trials in 2026, targeting NRAS-driven tumors with promising preclinical efficacy and safety.

Market opportunity and commercial strategy

• The second-line PI3K pathway inhibitor market is approaching a $1 billion run rate, with potential for rapid market share growth if phase III results are positive.

• The addressable market for vascular anomalies is estimated at $6–8 billion, with about 25,000 patients in the U.S. potentially eligible for chronic systemic therapy.

• Pricing precedent exists with alpelisib: $25,000/month for breast cancer and $36,000/month for vascular anomalies, suggesting differentiated pricing is feasible.

• Only a small fraction of the vascular anomalies population needs to be captured to achieve blockbuster sales, given high per-patient pricing.

• Early data in vascular anomalies supports a strong commercial profile, with plans to expand the eligible patient pool over time.

Regulatory and development outlook

• Accelerated approval for zovegalisib in vascular anomalies is being pursued, leveraging precedent from alpelisib’s approval pathway; discussions with the FDA are planned before year-end.

• The regulatory strategy includes pooling PROS and lymphatic malformation patients for accelerated approval, with a single-arm confirmatory study proposed for full approval.

• The first-line breast cancer phase III trial is targeted to start in early 2027, pending regulatory feedback and site readiness.

• Ongoing trials are designed to provide optionality for physicians to use zovegalisib in both first- and second-line settings, depending on patient profile and tolerability.

• Updates on trial enrollment, data, and regulatory milestones are expected throughout the next 12 months.