CSPC’s Becotatug Plus Osimertinib Shows Positive Results in EGFR Exon 20 Insertion NSCLC

CSPC’s becotatug (JMT101) in combination with osimertinib met the primary endpoint in a Phase III trial of patients with locally advanced or metastatic non-small cell lung cancer (NSCLC) harboring EGFR exon 20 insertion mutations (EGFR ex20ins). At a prespecified interim analysis, the chemotherapy-free regimen significantly prolonged progression-free survival (PFS) compared with platinum-based chemotherapy plus pemetrexed and showed a trend toward improved overall survival (OS).

Dual targeting of EGFR signaling

Becotatug is a high-affinity, humanized monoclonal antibody targeting EGFR. When combined with osimertinib, an EGFR tyrosine kinase inhibitor, the regimen targets EGFR signaling at both the extracellular and intracellular levels. This provides a chemotherapy-free, dual-targeted treatment approach for patients with EGFR ex20ins NSCLC.

EGFR mutations account for a substantial proportion of NSCLC in China, while EGFR ex20ins is an important subtype beyond classical EGFR mutations. These tumors show substantial molecular heterogeneity and a high proportion of brain metastases and often present with a higher tumor burden. Patients with locally advanced or metastatic disease continue to face clinical challenges in achieving durable disease control, improving long-term survival, and maintaining treatment tolerability.

Phase III trial meets prespecified superiority boundary

The randomized, open-label, parallel-controlled Phase III study compared becotatug plus osimertinib with platinum-based chemotherapy plus pemetrexed as first-line treatment. The primary endpoint was PFS assessed by an Independent Review Committee according to RECIST 1.1 criteria.

At the prespecified interim analysis, reviewed by the Independent Data Monitoring Committee, the becotatug-osimertinib combination crossed the predefined statistical superiority boundary for PFS and demonstrated a clinically significant benefit. The combination also showed a trend toward improved OS. CSPC reported a favorable safety profile for the regimen.

The announcement does not provide numerical PFS or OS estimates, hazard ratios, confidence intervals, or detailed adverse-event rates. The full dataset will therefore be important for assessing the magnitude, durability, and safety profile of the observed benefit.

Additional Phase III programs underway

CSPC is also evaluating becotatug in other clinical settings:

• Classical EGFR-mutated NSCLC: First-line treatment of locally advanced or metastatic nonsquamous NSCLC with classical EGFR mutations.
• Advanced metastatic colorectal cancer: Treatment after failure of at least two lines of standard therapies.

The company plans to present the EGFR ex20ins Phase III findings at upcoming academic conferences.

The positive interim result provides pivotal Phase III evidence for a chemotherapy-free dual-targeted approach in EGFR ex20ins NSCLC. Further clinical data and subsequent regulatory discussions will help define the regimen’s potential role in first-line treatment.

Reference

Phase Iii Clinical Trial of Becotatug (Jmt101) In Combination with Osimertinib for The First-Line Treatment of Locally Advanced or Metastatic NSCLC Harbouring EGFR Exon 20 Insertion Mutations Achieves Positive Topline Results, CSPC PHARMACEUTICAL, 24 September 2026

JMT101 in Combination With Osimertinib, Versus Cisplatin-pemetrexed in Participants With Locally Advanced or Metastatic Non-small Cell Lung Cancer (NSCLC) Characterized by Epithermal Growth Factor Receptor (EGFR) Exon 20ins Mutations, ClinicalTrials.gov ID NCT06380348