August 25, 2020
SymBio Pharmaceuticals Limited
Fuminori Yoshida
Representative Director
President and Chief Executive Officer(Securities Code: 4582)

Onconova Therapeutics Announces Topline Results from the Pivotal Phase 3 INSPIRE Trial
for Higher-Risk Myelodysplastic Syndromes (HR-MDS)TOKYO, Japan, August 25, 2020 -- SymBio Pharmaceuticals Limited (Headquarters: Tokyo,"SymBio") today announced that its U.S. licensor of rigosertib, Onconova Therapeutics, Inc.
(Headquarters: Newtown, PA, “Onconova”), a Phase 3 stage biopharmaceutical company focused on
discovering and developing novel products to treat cancer, announced on August 24, 2020 (EST) thatINSPIRE, the pivotal Phase 3 study assessing the efficacy and safety of IV rigosertib in higher-risk
MDS (HR-MDS) patients, did not meet its primary endpoint of improved survival.
The primary endpoint of the trial was overall survival, comparing IV rigosertib plus best supportive
care to physician's choice (PC) plus best supportive care in patients who had progressed on, failed torespond to, or relapsed after previous treatment with a hypomethylating agent (HMA) within ninecycles over the course of one year after initiation of HMA treatment. A pre-specified analysis in thevery high risk (VHR-MDS) patient subgroup was also conducted.
Results of INSPIRE demonstrated that in the intent-to-treat analysis patients randomized to IV
rigosertib achieved overall survival of 6.4 months, versus 6.3 months for PC (p=0.33) in the overall
HR-MDS population. Overall survival in the pre-specified VHR-MDS subgroup of patients was also
not significantly different between the two study arms. There was an increase in overall survival inthe PC arm post-interim analysis that was unexpected. Onconova is conducting additional analyses.
Safety analysis indicates that IV rigosertib was generally well tolerated, with reported adverse events
similar to those observed in previous clinical studies with IV rigosertib in MDS. Serious adverse
events (SAEs) were uncommon, with a similar profile of SAEs in both study arms.
Statement from Fuminori Yoshida, President and Chief Executive Officer of SymBio: "While theresults of the INSPIRE study are disappointing, we believe that rigosertib as a RAS pathway
inhibitor has potential applications in many other oncological areas beyond hematological diseases,
and we look forward to using the findings from the genomic analysis of the INSPIRE study in the1future development of rigosertib. In addition to the ongoing Phase 1/2a trial in KRAS+ lungadenocarcinoma, we look forward to continuing to expand the study to other solid tumors."
SymBio does not expect the information presented herein to have any material impact on its financial
outlook for the fiscal year ending December 2020.

About Rigosertib
Rigosertib is a small molecule inhibitor that has a new mechanism of action: it inhibits the activationof RAS as an oncogene-related product, thereby blocking the action of multikinases, including PI3K,and inhibits cellular signaling in cancer cells necessary for their survival and proliferation, thus
killing cancer cells. SymBio obtained the development and commercialization licensing rights for
Rigosertib from Onconova in July 2011 for Japan and Korea.
About Onconova Therapeutics, Inc.
Onconova Therapeutics, Inc. is a Phase 3-stage biopharmaceutical company focused on discoveringand developing novel drugs to treat cancer. Onconova has a pipeline of proprietary targeted agents
designed to work against specific cellular pathways that are important in cancer cells. Clinical trials
with Onconova’s compound rigosertib are aimed at what Onconova believes are unmet medical needsof patients with cancer. For more information, please visit https://www.onconova.com.
About SymBio Pharmaceuticals Limited
SymBio Pharmaceuticals Limited was established in March 2005 by Fuminori Yoshida who
previously served concurrently as Corporate VP of Amgen Inc. and founding President of Amgen
Japan. In May 2016, the Company incorporated its wholly-owned subsidiary in the U.S., SymBioPharma USA, Inc. (Headquarters: Menlo Park, California, President: Mr. Fuminori Yoshida).
The Company’s underlying corporate mission is to “deliver hope to patients in need” as it aspires to bea leading global specialty biopharmaceutical company dedicated to addressing underserved medicalneeds.

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