New Stem Cell-Based Application for BeyondSpring’s Plinabulin Presented at ISSCR Annual Meeting

June 30, 2020

Data Presented Shows Plinabulin Mobilizes Bone Marrow CD34+ Progenitor Cells through a Mechanism of Action Independent from G-CSFs and CXCR4

NEW YORK, June 30, 2020 (GLOBE NEWSWIRE) — BeyondSpring Inc. (the “Company” or “BeyondSpring”) (NASDAQ: BYSI), a global biopharmaceutical company focused on the development of innovative immuno-oncology cancer therapies, today announced that the Company presented clinical data on BeyondSpring’s first-in-class, late-stage asset, Plinabulin, showing potent CD34+ progenitor cell mobilization from bone marrow, which has broad applications for stem cell-based therapies, gene therapy and regenerative medicine. These findings potentially add another indication to Plinabulin, which is known as a “pipeline in a drug.” Dr. Ramon Mohanlal, BeyondSpring’s Chief Medical Officer and Executive Vice President, Research and Development, presented this new data as a poster at this year’s ISSCR Annual Meeting.

Current approved agents for CD34+ progenitor cell mobilization, such as G-CSFs or Plerixafor (CXCR4-antagonist), have many limitations. While G-CSFs are highly effective in preventing chemotherapy-induced neutropenia (CIN), they come with severe side effects, such as bone pain and thrombocytopenia. To add, multiple doses of short-acting G-CSFs (up to six or seven) are often needed for the therapy to be effective. Plerixafor is also given by daily injections for four to five days and is a very expensive process and not as effective for CD34+ cells (American Health and Drug Benefits, 2012).

Additionally, G-CSFs are contra-indicated in Sickle Cell Disorder (SCD) patients undergoing gene therapy. This results in high rates of adverse events requiring hospitalization, including vaso-occlusive crises, multi-organ failure and even death (Chien, Haematologica 2018). Lastly, when side effects such as bone pain, leukocytosis (high white blood cell count) and / or myalgia (muscle pain) occur, a G-CSF dose is often reduced to 50 percent, which is less effective for CD34+ cell mobilization.

Plinabulin is a novel and potent agent for the prevention of CIN and does not cause bone pain or thrombocytopenia. Plinabulin is given as a single fixed dose (40mg) – as a 30-minute intravenous infusion – and has a mechanism of action independent from G-CSF of CXCR4.

In BeyondSpring’s PROTECTIVE-2 Phase 2 study, the team evaluated the effects of CD34+ cell mobilization through combining Plinabulin with the full dose of Pegfilgrastim (Peg) at 6mg and at lower doses of 3mg and 1.5mg in breast cancer patients receiving taxotere, doxorubicin and cyclophosphamide (TAC).

The data shows that combining Plinabulin with a low dose of Pegfilgrastim produces statistically significant CD34+ cell counts (p<0.03) and increases to values that are comparable to, or numerically higher than, the full dose of Pegfilgrastim alone under severe myelosuppressive conditions.
In BeyondSpring’s PROTECTIVE-1 Phase 2 study, the Company previously reported that lung cancer patients receiving docetaxel who received a single dose of Plinabulin saw an increase of CD34+ counts to clinically and statistically significant (p<0.001) levels under myelosuppressive conditions (Blayney, ASH 2018).

The above data presentation is available on the “Posters” page of BeyondSpring’s website. Please click here for more information.

“Plinabulin’s mechanism of action for CD34+ cell mobilization, which is independent from G-CSFs or CXCR4, offers an important alternative to patients who do not adequately respond to these agents, including patients where G-CSFs are contra-indicated,” said Dr. Mohanlal. “Stem cell-based applications, such as gene therapy, is bound to become the standard of care for SCD, for which Plinabulin is well-positioned for CD34+ cell mobilization, given that G-CSFs are contra-indicated for SCD patients. With more than 100,000 SCD patients in the U.S. alone, this represents a near-term opportunity for Plinabulin, along with other CD34+ progenitor cell applications.”

About BeyondSpring
Headquartered in New York, BeyondSpring is a global, clinical-stage biopharmaceutical company focused on developing innovative immuno-oncology cancer therapies to improve clinical outcomes for patients with high unmet medical needs. BeyondSpring’s first-in-class lead immune asset, Plinabulin, is a potent antigen-presenting cell (APC) inducer. It is currently in two Phase 3 clinical trials for two severely unmet medical needs indications: one is for the prevention of chemotherapy-induced neutropenia (CIN), the most frequent cause for a chemotherapy regimen dose’s decrease, delay, downgrade or discontinuation, which can lead to suboptimal clinical outcomes. The other is for non-small cell lung cancer (NSCLC) treatment in EGFR wild-type patients. As a “pipeline drug,” Plinabulin is in various I/O combination studies to boost PD-1 / PD-L1 antibody anti-cancer effects. In addition to Plinabulin, BeyondSpring’s extensive pipeline includes three pre-clinical immuno-oncology assets and a drug discovery platform dubbed “molecular glue” that uses the protein degradation pathway.

About Plinabulin
Plinabulin, BeyondSpring’s lead asset, is a differentiated immune and stem cell modulator. Plinabulin is currently in late-stage clinical development to increase overall survival in cancer patients, as well as to alleviate chemotherapy-induced neutropenia (CIN). The durable anticancer benefits of Plinabulin have been associated with its effect as a potent antigen-presenting cell (APC) inducer (through dendritic cell maturation) and T-cell activation (Chem and Cell Reports, 2019). Plinabulin’s CIN data highlights the ability to boost the number of hematopoietic stem / progenitor cells (HSPCs), or lineage-/cKit+/Sca1+ (LSK) cells in mice. Effects on HSPCs could explain the ability of Plinabulin to not only treat CIN but also to reduce chemotherapy-induced thrombocytopenia and increase circulating CD34+ cells in patients.

Cautionary Note Regarding Forward-Looking Statements
This press release includes forward-looking statements that are not historical facts. Words such as “will,” “expect,” “anticipate,” “plan,” “believe,” “design,” “may,” “future,” “estimate,” “predict,” “objective,” “goal,” or variations thereof and variations of such words and similar expressions are intended to identify such forward-looking statements. Forward-looking statements are based on BeyondSpring’s current knowledge and its present beliefs and expectations regarding possible future events and are subject to risks, uncertainties and assumptions. Actual results and the timing of events could differ materially from those anticipated in these forward-looking statements as a result of several factors including, but not limited to, difficulties raising the anticipated amount needed to finance the Company’s future operations on terms acceptable to the Company, if at all, unexpected results of clinical trials, delays or denial in regulatory approval process, results that do not meet our expectations regarding the potential safety, the ultimate efficacy or clinical utility of our product candidates, increased competition in the market, and other risks described in BeyondSpring’s most recent Form 20-F on file with the U.S. Securities and Exchange Commission. All forward-looking statements made herein speak only as of the date of this release and BeyondSpring undertakes no obligation to update publicly such forward-looking statements to reflect subsequent events or circumstances, except as otherwise required by law.