Zipalertinib Plus Chemotherapy Cuts Progression Risk 50% in First-Line EGFR Exon 20 Insertion NSCLC
核心洞察
The Phase 3 REZILIENT3 trial met its primary endpoint, showing zipalertinib plus platinum-based chemotherapy extended median progression-free survival to 14.5 months versus 8.5 months with chemotherapy alone.
The combination reduced the risk of disease progression or death by 50% (HR 0.50; 95% CI, 0.34-0.73; P=0.00015) in previously untreated advanced EGFR (搜索) exon 20 insertion NSCLC.
Objective response rate rose to 65.0% with the combination versus 40.3% with chemotherapy alone, with median duration of response of 14.2 versus 9.9 months.
Adding zipalertinib to platinum-based chemotherapy significantly improved progression-free survival (PFS) in patients receiving first-line treatment for advanced non-small cell lung cancer (搜索) (NSCLC) harboring EGFR (搜索) exon 20 insertion (ex20ins) mutations, according to results from the Phase 3 REZILIENT3 trial presented at the International Association for the Study of Lung Cancer's (IASLC) 2026 World Conference on Lung Cancer (WCLC) in Seoul, South Korea.
The late-breaking data from a planned interim analysis were featured in Presidential Symposium 2, a plenary session reserved for advances with the potential to change clinical practice. Taiho Oncology (搜索), Inc., Taiho Pharmaceutical (搜索) Co., Ltd., and Cullinan Therapeutics, Inc. (Nasdaq: CGEM) announced the findings on September 13, 2026.
Primary Endpoint Met With Six-Month PFS Gain
At the pre-planned interim efficacy analysis after 122 PFS events, median PFS assessed by blinded independent central review was 14.5 months with zipalertinib plus chemotherapy compared with 8.5 months with chemotherapy alone — a 6.0-month improvement representing a 50% reduction in the risk of disease progression or death (HR=0.50; 95% CI, 0.34-0.73; P=0.00015).
"The combination of zipalertinib plus platinum-based chemotherapy in the REZILIENT3 trial demonstrated a statistically significant and clinically meaningful improvement in progression-free survival for patients with advanced non-small cell lung cancer (搜索) harboring EGFR (搜索) exon 20 insertion mutations," said Helena A. Yu, MD, Thoracic Medical Oncologist at Memorial Sloan Kettering Cancer Center and study investigator. "The combination also produced significantly higher response rates compared with chemotherapy alone."
The PFS benefit was consistent across subgroups, including patients with brain metastases, in whom the hazard ratio was 0.38.
Response Rates and Duration of Response
Objective response rate was significantly higher with the combination therapy at 65.0% versus 40.3% with chemotherapy alone (P<0.0001). Median duration of response was also longer with the combination, at 14.2 months compared with 9.9 months.
"The magnitude of progression-free survival benefit, together with improvements in response rates and duration of response seen in REZILIENT3, reinforce the potential for zipalertinib plus chemotherapy to play an important role in the first-line treatment of patients with EGFR exon 20 insertion mutation (搜索) NSCLC," said Jeffrey Jones, MD, MBA, Chief Medical Officer, Cullinan Therapeutics.
Overall Survival Data Remain Immature
At the interim overall survival (OS) analysis, which had reached 30% event maturity, the hazard ratio for death with zipalertinib plus chemotherapy versus chemotherapy alone was 0.72 (95% CI, 0.42-1.23). Continued follow-up of REZILIENT3 is ongoing to further characterize the OS benefit and exploratory endpoints (ClinicalTrials.gov number NCT05973773).
Trial Design and Patient Population
REZILIENT3 is a multicenter, randomized, controlled, open-label global trial that enrolled 285 adults with previously untreated, locally advanced or metastatic non-squamous NSCLC with EGFR (搜索) exon 20 insertion mutations. Following a six-patient safety lead-in, 279 patients were randomly assigned 1:1 to receive zipalertinib 100 mg twice daily plus platinum-pemetrexed chemotherapy (搜索) (n=140) or chemotherapy alone (n=139). The primary objective was to assess PFS in the combination arm versus the chemotherapy arm.
Baseline characteristics were balanced between the combination and control arms, including age (66.5 vs. 64 years), sex (65.7% vs. 63.3% female), and brain metastases (31.4% vs. 31.7%). Patients with untreated, asymptomatic brain metastases up to 2 cm were eligible, and patients assigned to chemotherapy alone could cross over to zipalertinib after disease progression.
"REZILIENT 3 demonstrated that adding zipalertinib to platinum-based chemotherapy produced a statistically significant and clinically meaningful six-month improvement in progression-free survival for patients with advanced NSCLC and EGFR (搜索) exon 20 insertion mutations," said Professor Daniel Tan, of National Cancer Centre Singapore and Duke-NUS Medical School, Singapore, who presented the data.
Safety Profile Consistent With Individual Agents
The observed adverse event (AE) profile of zipalertinib plus chemotherapy was generally consistent with the known safety profiles of the individual agents, and no new safety signals were observed. Grade ≥3 AEs occurred more frequently with the combination (87.1% vs. 54.4%), but these were primarily manageable hematologic AEs (58.6% vs. 28.7%).
Grade ≥3 EGFR (搜索)-related toxicities were infrequent and occurred only in the combination arm, including rash (10.7%), stomatitis (5.0%), pneumonitis (2.1%), and diarrhea (1.4%).
An Orally Available, Irreversible EGFR Inhibitor
Zipalertinib (development code: CLN-081/TAS6417) is an orally available small molecule designed to target activating mutations in EGFR (搜索). The molecule was selected for its ability to inhibit EGFR variants with exon 20 insertion mutations and is designed as a next-generation, irreversible EGFR inhibitor for a genetically defined subset of NSCLC patients. Zipalertinib is investigational and has not been approved by any health authority.
The agent is being developed by Taiho Oncology (搜索), Inc., its parent company Taiho Pharmaceutical (搜索) Co., Ltd., and in collaboration with Cullinan Therapeutics, Inc. in the U.S.
A Genetically Defined Population With Limited Options
NSCLC is a common form of lung cancer, and up to 4% of all cases globally have EGFR (搜索) ex20ins. In the United States, approximately 16% of patients with NSCLC harbor EGFR mutations, with insertions at exon 20 accounting for up to 12% of these mutations. These mutations are associated with limited treatment options and poorer outcomes compared with more common EGFR mutations.
"The findings presented add to previously presented single agent zipalertinib data and support the potential of zipalertinib across multiple treatment settings," said Harold Keer, MD, PhD, Chief Medical Officer of Taiho Oncology (搜索). "We are excited to discuss these results further with health authorities and collaborate to make zipalertinib available to patients in a timely manner."
"We believe these results mark a potentially important step forward in the treatment of EGFR exon 20 insertion mutation (搜索)-positive non-small cell lung cancer (搜索)," said Fabio Benedetti, MD, Global Chief Medical Officer, Taiho Pharmaceutical (搜索).