November 8, 2019
SymBio Pharmaceuticals Limited
Fuminori Yoshida
Representative Director
President and Chief Executive Officer(Securities Code: 4582)

Onconova Announces Presentations on Rigosertib inMyelodysplastic Syndromes at the ASH 2019 Annual Meeting & Exposition
TOKYO, Japan, November 8, 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 November 7, 2019 (EST) that the below
abstract relating to Rigosertib was accepted for oral presentation at the 61st American Society ofHematology (ASH) Annual Meeting & Exposition in Orlando, Florida, which takes place December 710, 2019.
Oral Presentation: Phase Ⅱ Study of Oral Rigosertib Combined with Azacitidine (AZA) As First Line

Therapy in Patients (Pts) with Higher-Risk Myelodysplastic Syndromes (HR-MDS)
The presenter will be Shyamala C. Navada, MD, Division of Hematology/Oncology, Icahn School ofMedicine at Mount Sinai, New York, NY. The session will be held on December 9th, 2019.
SymBio plans to participate in an Onconova-initiated global clinical trial for the continued
development of oral rigosertib in combination with azacitidine in first-line HR-MDS patients.
In addition to the above oral presentation, four poster presentations on rigosertib in
Myelodysplastic Syndromes were also accepted.
For more information, please see Onconova’s website:
investor.onconova.com/press-releases

1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 myelogenousleukemia (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 RigosertibRigosertib 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 the
pre-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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