December 10, 2019
SymBio Pharmaceuticals Limited
Fuminori Yoshida
Representative Director
President and Chief Executive Officer(Securities Code: 4582)

Onconova Announces Data from the INSPIRE Trial and Updated Oral Rigosertib Data
at the American Society of Hematology (ASH) 2019 Annual Meeting
TOKYO, Japan, December 10, 2019 -- SymBio Pharmaceuticals Limited (Headquarters: Tokyo,"SymBio") today announced that its U.S. licensor for Rigosertib, Onconova Therapeutics, Inc.,(Headquarters: Newtown, PA, “Onconova”) announced on December 9, 2019 (EST) that Onconova
presented genomics data from the INSPIRE Trial (the international trial of Phase 3 IV Rigosertib) at
the 61st American Society of Hematology (ASH) Annual Meeting. In addition, updated data from thePhase 2 Trial of Oral Rigosertib + Azacitidine (AZA) Versus Single Agent AZA in Treatment-Naive
Patients with HR-MDS was presented in an oral presentation. The updated data from the Phase 2Trial informs the design of a planned adaptive clinical trial in HMA naïve HR-MDS.
Key topics covered in Onconova’s announcement:
Genomic Profiling at Study Entry in Patients with Higher Risk Myelodysplastic Syndrome(HR-MDS) Following Hypomethylating (HMA) Failure: Results From the INSPIRE Trial,including RAS and other Mutations

New Data Presented at the ASH 2019 Annual Meeting Provides Insights for Potential Future
Development Plans for Oral Rigosertib

Oral Presentation of Updated Data on the Novel Combination of Oral Rigosertib + Azacitidine(AZA) Versus Single Agent AZA in Treatment-Naive Patients with HR-MDS

3 Additional Abstract Presentations at ASH 2019 Annual Meeting

For more information, please see Onconova’s website:
investor.onconova.com/press-releases
Patients with high-risk MDS who are refractory to HMAs have limited treatment options, and there
is an extremely high unmet medical need for patients who respond inadequately to existing therapies.
In collaboration with Onconova, SymBio has been conducting the international Phase 3 INSPIRE
Trial designed to assess the efficacy and safety of intravenous rigosertib and steadily advancing theenrollment of patients in Japan. SymBio also plans to participate with respect to Japan in an1

Onconova planned international clinical trial for oral rigosertib in combination with azacitidine inHMA naïve HR-MDS patients.
About myelodysplastic syndromes (MDS)MDS patients often require frequent blood transfusions due to the development of severe anemia(decrease in the number of red blood cells), with a high rate of progression to acute myelogenous
leukemia (AML). The number of MDS cases is expected to increase as the population ages. MDS andAML are widely recognized as two blood disorders that are difficult to manage given the limited
therapeutic options available for patients. A high unmet medical need clearly exists for theestablishment of new effective therapies to treat both lower-risk and higher-risk MDS. The number ofdrug-treated MDS patients is estimated to be approximately 11,000 in Japan at male to female ratioof 2 to 1. The majority of the patients are elderly.
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 licensed the development and commercialization rights for Rigosertib
from Onconova in July, 2011 for Japan and Korea.
About Onconova Therapeutics, Inc.
Onconova Therapeutics, Inc. is a clinical-stage biopharmaceutical company focused on discoveringand developing novel products to treat cancer. Onconova's clinical and pre-clinical stage drug
development candidates are derived from its extensive chemical library and are designed to work
against specific cellular pathways that are important in cancer cells, while causing minimal damage
to normal cells. In addition to Rigosertib, Onconova's most advanced drug candidate underdevelopment, two other drug candidates are in clinical trials and several other compounds are in thepre-clinical stage of development. For more information, please visit Onconova’s website at: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., called
SymBio Pharma 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 medical
needs.

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