BeyondSpring Announces Poster Presentation at 2026 ASCO Annual Meeting

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 an upcoming poster presentation of Study 303, an investigator-initiated study supported by Merck, known as MSD outside of the United States and Canada, and BeyondSpring, in patients with 2L/3L NSCLC who progressed on PD-1/PD-L1 inhibitors , at the 2026 American Society of Clinical Oncology (ASCO) Annual Meeting , taking place May 29 through June 2 in Chicago, IL.

Presentation details are as follows:

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, Xiao-Yian Liu, Wei Zhong, Jing Zhao, RuiLi Pan, Taisheng Li, Mengzhao Wang

Presentation Time: Sunday, May 31, 2026, from 9:00 a.m. to 12:00 p.m. CDT

Location: McCormick Place, Chicago, IL

Session: Lung Cancer – Non-Small Cell Metastatic

Abstract Number: 8567

Poster Board Number: 357

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 . Learn more at beyondspringpharma.com.

About Study 303

Study 303 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, Beijing, China with Dr. Mengzhao Wang, Chief of the Department of Respiratory and Critical Care Medicine, as the principal investigator, with support from MSD. 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.

Forward-Looking Statements

This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. These statements involve known and unknown risks and uncertainties that may cause BeyondSpring’s actual results to differ materially from those stated or implied. BeyondSpring undertakes no obligation to update forward-looking statements.

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