May 25, 2021
SymBio Pharmaceuticals Limited
Fuminori Yoshida
Representative Director
President and Chief Executive Officer(Securities Code: 4582)

New Patent Issued in Japan for Antiviral Agent Brincidofovir
TOKYO, Japan, May 25, 2021 -- SymBio Pharmaceuticals Limited (Headquarters: Tokyo, "SymBio")
today announced that an additional patent has been issued in Japan for antiviral agent brincidofovir.
Pursuant to a license agreement entered into between SymBio and Chimerix Inc. (Headquarters:Durham, NC, "Chimerix") on September 30, 2019, SymBio obtained the exclusive worldwide rights todevelop, manufacture, and commercialize BCV in all human indications, excluding the prevention
and treatment of orthopox infections.
[Title of the invention] Formulations of brincidofovir[Patent No.] No. 6878473[Patentee] Chimerix Inc.
[Filing date] June 28, 2017
[Registration Date] May 6, 2021
[Term] Expiring on June 28, 2037
[Summary] Pharmaceutical compositions of brincidofovir for intravenous administration.
The Company does not expect the information presented herein to have any material impact on its
financial outlook for the fiscal year ending December 31, 2021.
[Contact]
Investor Relations
Tel: +81 (0)3 5472 1125

1About Anti-viral Drug Brincidofovir
Brincidofovir (BCV) is a lipid-conjugate of cidofovir (an antiviral drug already approved and marketedin the U.S. and Europe, but unapproved in Japan; “CDV”). In addition to its antiviral effect, BCV wasintended to be designed to have improved safety profile as compared to CDV. Therefore, BCV isexpected to be an effective treatment for a wide range of DNA viruses (e.g., herpesviruses such as
cytomegalovirus (CMV), adenovirus (AdV), BK virus, papillomavirus, etc.).
Moreover, BCV is an easy-to-use and novel highly active antimultiviral agent that can reduce the riskof nephrotoxicity, which is a serious side effect of CDV.
SymBio entered into an exclusive global license agreement with Chimerix for brincidofovir (BCV) on
September 30, 2019. Under the terms of the agreement, Chimerix grants SymBio exclusive worldwide
rights to develop, manufacture, and commercialize BCV in all human indications, excluding theprevention and treatment of orthopox infections (which includes smallpox and monkeypox).
SymBio aims to further globalize business, establish an integrated system for the supply of highquality pharmaceutical products, and grow as a specialty pharmaceutical company through theexclusive global license for BCV. To develop global operations, the Company is considering
partnerships that will utilize regional characteristics of the target diseases and striving to maximize
the business value of the products and to deliver to patients who need our products as soon as
possible. The Company aims to serve the patients not only in Japan but also in Europe and the U.S.
market where the market size for organ transplantation is large, and Asia, including the Chinesemarket.
For further information, please see the SymBio’s press release dated October 1, 2019,https://www.symbiopharma.com/news/20191001.pdf
About Chimerix
Chimerix is a development-stage biopharmaceutical company dedicated to accelerating theadvancement of innovative medicines that make a meaningful impact in the lives of patients livingwith cancer and other serious diseases. Its three most advanced clinical-stage development programs
are BCV, ONC201 and DSTAT. BCV is an antiviral drug candidate developed as a potential medical
countermeasure for smallpox and is currently under review for regulatory approval in the UnitedStates. ONC201 is currently in a registrational clinical program for recurrent H3 K27M-mutant
glioma and a confirmatory response rate assessment is expected later this year. DSTAT is indevelopment as a potential first-line therapy in acute myeloid leukemia. For further information,please visit the Chimerix website, www.chimerix.com.

2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 medicalneeds.

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