BeyondSpring Presents the Latest Update of a Phase 2 Study Demonstrating Durable Clinical Benefit of Pembrolizumab Plus Plinabulin/Docetaxel in Metastatic NSCLC After Progression on First-Line Immune Checkpoint Inhibitor Therapy at ASCO 2026

Meaningful clinical benefit: Median PFS at 7.0 months, median DoR is 9.3 months with DCR of 79.5% in metastatic NSCLC patients with acquired resistance to immune checkpoint inhibitors

Durable survival benefit: 12-month OS rate of 78.1% and 24-month OS rate of 58.0% in a patient population with limited treatment options

Good tolerability and immune activation: Along with increased frequencies of activated CD4+/CD8+ T cells post-treatment, hematology test also showed safety benefit with significantly higher levels of WBCs, neutrophils and platelets.

FLORHAM PARK, N.J., June 02, 2026 (GLOBE NEWSWIRE) -- BeyondSpring Inc. (NASDAQ: BYSI) (“BeyondSpring” or the “Company”), a clinical-stage company developing transformative therapies for the treatment of cancer and other diseases, today announced updated efficacy and safety data from the investigator-initiated Phase 2 303 Study evaluating pembrolizumab plus Plinabulin and docetaxel in patients with metastatic non-small cell lung cancer (“NSCLC”) after progression on first-line immune checkpoint inhibitor (“ICI”) therapy, either alone or in combination with chemotherapy. The data were presented at the 2026 American Society of Clinical Oncology (“ASCO”) Annual Meeting by Dr. Mengzhao Wang and Dr. Yan Xu, principal investigators from Peking Union Hospital.

First-in-class small molecule agent Plinabulin is a brain-penetrant, uniquely reversible tubulin binder with immunomodulatory properties that promote dendritic cell maturation, M1 polarization and anti-tumor T-cell responses. As a GEF-H1 agonist, Plinabulin is designed to strengthen the cancer-immunity cycle, support immune activation, and help address chemotherapy-induced neutropenia, providing a potential differentiated approach in the post-ICI treatment setting.

The open-label Phase 2 study enrolled 47 patients with metastatic NSCLC who had progressed following prior ICI therapy, including 6 patients previously treated with ICI alone and 41 patients previously treated with ICI plus platinum-doublet chemotherapy. All patients had secondary resistance, defined as prior ICI treatment with progression-free survival of at least six months. Pembrolizumab (200 mg), Plinabulin (30 mg/m 2 ) and docetaxel (75 mg/m 2 ) were all dosed intravenously on day 1 of a 21-day cycle.

As of the February 28, 2026 data cutoff, the median follow-up was 28.8 months. Three patients remained on treatment, and 24 patients remained alive in survival follow-up. Among the 47 enrolled patients, the median age was 67 years; 80.9% were male and 19.1% were female; 72.3% were current or former smokers; and histology included 63.8% non-squamous and 36.2% squamous NSCLC. The key results at the database lock are summarized below.

Median Progression-Free Survival (PFS): 7.0 months — compared favorably with historical docetaxel data in similar post-ICI patient populations, including TROPION-Lung01 and EVOKE-01, which reported median PFS of 3.7 months and 3.9 months, respectively

Median Duration of Response (DoR): 9.3 months – indicating durable response

Disease Control Rate (DCR: PR + SD > 4 months): 79.5% — indicating clinical benefit in the majority of patients who progressed on prior PD-1/L1 inhibitor-based therapy

Confirmed Objective Response Rate (ORR): 18.2% — compared favorably with historical 5-12% ORR for docetaxel, demonstrating anti-tumor activity in metastatic NSCLC patients with secondary resistance to prior ICI

12-Month Overall Survival (OS) Rate: 78.1%; 24-Month OS Rate: 58.0%, with median OS not reached — compared favorably with historical docetaxel data in similar patient populations, including TROPION-Lung01 and EVOKE-01, which reported median OS of 11.8 months and 9.8 months, respectively

The combination demonstrated a generally manageable safety profile. 53.2% of patients experienced grade 3 or higher treatment-related adverse events, including hypertension in 17.0%, gastrointestinal disorders in 14.9%, neutrophil decrease in 17.0%, decreased white blood cell count in 6.4%, and febrile neutropenia in 2.1%

“These updates continue to support Plinabulin’s potential to address one of the most significant unmet needs in lung cancer: treatment options for patients whose disease has progressed after ICI therapy,” said Dr. Mengzhao Wang, principal investigator from Peking Union Hospital in China. “With 24-month OS rate of 58%, together with 80% of disease control and encouraging immune activation and hematologic benefit, we believe Plinabulin may offer a differentiated approach to re-sensitizing tumors to immunotherapy with durable long-term benefit while improving the therapeutic profile of docetaxel-based regimens.”

BeyondSpring’s ASCO 2026 Presentation

Title: A Phase 2 Study of Plinabulin (Plin)/Docetaxel (Doc) plus Pembrolizumab (Pemb) in Metastatic NSCLC (mNSCLC) After Acquired Resistance (AR) to Anti-PD-1/L1 Alone or in Chemotherapy Combination: Efficacy and Immunophenotyping

Presenter/Authors: Yan Xu, Minjiang Chen, Xiaoxing Gao, Huiyu Huang, Yue Chang, Xiaoyan Liu, Wei Zhong, Jing Zhao, RuiLi Pan, Taisheng Li, Mengzhao Wang

Session : Lung Cancer – Non-Small Cell Metastatic (Track)

Abstract Number: 8567

About BeyondSpring

BeyondSpring (NASDAQ: BYSI) is a clinical-stage biopharmaceutical company developing first-in-class therapies for cancers with high unmet need. Its lead asset, Plinabulin, has been studied in over 700 cancer patients and is in late-stage development across multiple cancer indications, with results published in The Lancet Respiratory Medicine. Plinabulin’s novel mechanism as a GEF-H1 agonist with dendritic cell maturation benefit supports both anti-cancer activity and immune modulation, offering a unique approach to re-sensitizing tumors resistant to checkpoint inhibitors. In addition, it has the potential to synergize with chemotherapy, antibody drug conjugates (ADC), radiation, and checkpoint inhibitors. Learn more at beyondspringpharma.com.

About the 303 Study

The 303 Study is an open-label, single-arm Phase 2 study of Plinabulin plus docetaxel and pembrolizumab for previously treated patients with metastatic NSCLC and progressive disease after anti-PD-(L)1 inhibitor alone or in combination with platinum-doublet chemotherapy. This study evaluates the efficacy and safety of this triple combination and is being conducted at Peking Union Medical College Hospital in Beijing, China, with Dr. Mengzhao Wang, Chief of the Department of Respiratory and Critical Care Medicine, as the principal investigator, with support from Merck. The study enrolled 47 patients. The primary endpoint is investigator-based ORR (RECIST 1.1). The secondary endpoints include PFS, OS, DoR, and safety. The regimen includes pembrolizumab 200 mg IV every three weeks (Q3W) on Day 1, docetaxel 75 mg/m 2 IV Q3W on Day 1, and plinabulin 30 mg/m 2 IV Q3W on Day 1 in a 21-day cycle. The study is funded by Merck’s Investigator Studies Program and BeyondSpring with provision of study drug and financial support. The study is registered on ClinicalTrials.gov under NCT05599789.

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