Revolution Medicines recently announced updated Phase 1 data for zoldonrasib in patients with previously treated KRAS G12D-mutated non-small cell lung cancer (NSCLC), presented at the AACR Annual Meeting 2026. As a selective inhibitor targeting one of the most historically “undruggable” KRAS mutations, these early findings provide an initial look at safety and early antitumor activity in a heavily pretreated population. While still preliminary, the data highlight emerging progress in targeting KRAS G12D, a space with significant unmet clinical need.

Clinical Takeaway

Early Phase 1 data for zoldonrasib demonstrate preliminary antitumor activity with a manageable safety profile in patients with previously treated KRAS G12D-mutated NSCLC. While these findings are encouraging, they remain early and dose-escalation-based, with additional data needed to define durability, optimal dosing, and broader clinical applicability. Importantly, this represents continued progress in targeting KRAS G12D, an area that has historically lacked effective targeted therapies.

Drug Profile & Mechanism

  • Agent:
    • Zoldonrasib – Selective KRAS G12D inhibitor
  • Class & Mechanism of action:
    • Directly targets KRAS G12D-mutant protein and inhibits oncogenic signaling pathways driving tumor growth
  • Route of administration & Dosing Schedule:
    • Oral agent, evaluated across dose-escalation cohorts in Phase 1 setting

Target Population

  • Patients with previously treated advanced or metastatic KRAS G12D-mutated NSCLC

Phase I Study Design (NCT06162221)

  • Study Type: Phase 1, open-label, dose-escalation and expansion study
  • Population: Patients with advanced solid tumors harboring KRAS G12D mutations
  • Treatment Regimen: Zoldonrasib administered orally across escalating dose cohorts

Endpoints

  • Primary Endpoint:
    • Safety and tolerability
    • Determination of dose-limiting toxicities (DLTs)
  • Key Secondary Endpoints:
    • Objective response rate (ORR)
    • Disease control rate (DCR)
    • Duration of response (DoR)
    • Pharmacokinetics and pharmacodynamics

Efficacy Outcomes

  • Primary Endpoint Results:
    • Early responses observed in patients with KRAS G12D-mutated NSCLC
    • Evidence of tumor reduction in select patients
  • Additional Signals:
    • Disease control observed across multiple dose levels
    • Duration of response remains immature given early follow-up

Safety

  • Overall Safety Profile:
    • Zoldonrasib demonstrated a manageable safety profile in early-phase evaluation
  • Common Adverse Events:
    • Primarily low-grade treatment-related adverse events (specifics dependent on dataset reporting)
  • Grade ≥3 Events:
    • Limited high-grade toxicities reported to date
  • Treatment-Related Discontinuations:
    • Low rates observed in early analysis

Key Clinical Implications

✔ KRAS G12D remains a historically difficult target, with limited effective therapies available

✔ Early data suggest proof-of-concept activity for direct KRAS G12D inhibition

✔ Findings are preliminary and not practice-changing, requiring further validation in expansion cohorts and later-phase trials

✔ Safety profile appears manageable, supporting continued dose optimization and development

✔ Highlights the importance of molecular testing and clinical trial enrollment for patients with KRAS-mutated NSCLC

Bottom Line

Zoldonrasib demonstrates encouraging early-phase activity in KRAS G12D-mutated NSCLC, with a manageable safety profile in a heavily pretreated population. While these findings represent an important step forward in targeting a previously elusive mutation, the data remain early and exploratory, with additional follow-up needed to confirm durability and clinical benefit.

Sources:

  • American Association for Cancer Research. (2026). AACR Annual Meeting 2026. https://www.aacr.org/meeting/aacr-annual-meeting-2026/
  • ClinicalTrials.gov. (2026). A study of zoldonrasib in patients with advanced solid tumors harboring a KRAS G12D mutation (NCT06162221). National Library of Medicine. https://clinicaltrials.gov/study/NCT06162221
  • Revolution Medicines. (2026, April 19). Revolution Medicines to present updated Phase 1 clinical data for zoldonrasib in patients with previously treated KRAS G12D non-small cell lung cancer at the 2026 AACR Annual Meeting. GlobeNewswire. https://www.globenewswire.com/news-release/2026/04/19/3276666/0/en/revolution-medicines-to-present-updated-phase-1-clinical-data-for-zoldonrasib-in-patients-with-previously-treated-kras-g12d-non-small-cell-lung-cancer-at-the-2026-aacr-annual-mee