June 14, 2022
SymBio Pharmaceuticals Limited
Fuminori Yoshida
Representative Director
President and Chief Executive Officer(Securities Code: 4582)

SymBio submits clinical trial notification to PMDA forPhase 2 clinical trial of anti-viral drug brincidofovir IV for patients with
BK virus infection after renal transplantation
TOKYO, Japan, June 14, 2022 -- SymBio Pharmaceuticals Limited (Headquarters: Tokyo, “theCompany”) today announced that it has submitted a clinical trial notification (CTN) to thePharmaceuticals and Medical Devices Agency (PMDA) to commence an international phase 2 clinicaltrial (the "Study") of an intravenous formulation of its anti-viral drug brincidofovir ("BCV IV") for
patients with BK virus infection after renal transplantation in Japan.
The Study will evaluate the safety, tolerability, and efficacy of BCV IV in patients with BK virus
infection after renal transplantation1, for whom there is currently no effective treatment, and will
determine the appropriate dosage and administration for the subsequent clinical trial.
Given brincidofovir's broad antiviral activity in vitro against various dsDNA viruses2, BCV IV isexpected to demonstrate efficacy in the treatment and prevention of viral infections following
hematopoietic stem cell transplantation and organ transplantation. The Company is prioritizing
development for BK virus infection in patients after renal transplantation, which can be fatal due todecreased renal function and loss of the transplanted kidney (graft loss), and for which there is a highlevel of unmet medical need worldwide due to lack of effective treatment. For this international
clinical trial, the Company is preparing clinical trials for BK virus infection after renaltransplantation in Australia and other regions as well as in Japan.
The Company does not expect the information presented herein to have any material impact on its
financial outlook for the fiscal year ended December 31, 2022.

[Contact]
Investor Relations
Tel: +81 (0)3 5472 1125

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(Note 1) Renal transplantation and infection
Renal transplantation is a procedure in which a new kidney is surgically transplanted to restore
kidney function for patients suffer from decreased renal function. However, the immune system of thetransplant recipient may recognize the transplanted organ as a foreign body and attempt to destroy it(organ rejection). Fever, malaise, irritation of the peritoneum, and pain in the wound may cause
damage to the transplanted kidney and may destroy the transplanted organ within approximately aweek. Immunosuppressants should be used before surgery to reduce organ rejection and protect thetransplanted kidney.
Immune recovery after transplantation takes a long time. However, because immunity is severelycompromised, especially immediately after transplantation, the transplant recipient becomessusceptible to various infectious diseases against which it is important to take effective measures
early. The prognosis of transplanted kidneys with BK virus nephropathy is poor, and about half aresaid to move toward loss of the transplanted kidney (graft loss).
There is no established effective therapy for the various infections after renal transplantation, andhealthcare providers have long sought an effective and safe treatment.
(Note 2) Double-stranded DNA (dsDNA) viruses
Double-stranded DNA (dsDNA) viruses includes Herpesviridae (e.g., CMV, HHV-6), adenoviridae(AdVs), polyomaviridae (e.g., BK virus and JC virus), papillomaviridae (HPVs), and poxviridae.

About the Anti-viral Drug Brincidofovir
Brincidofovir (BCV) is a lipid conjugate of cidofovir (CDV). CDV is an antiviral drug already approved
and marketed in the United States and the European Union, but unapproved in Japan. As BCV
exhibits not only higher anti-viral activity, but also a superior safety profile in comparison with CDV,
BCV is expected to be an effective treatment against a wide spectrum of dsDNA viruses such as
herpesviruses such as cytomegalovirus (CMV), adenovirus (AdV), Epstein-Barr virus (EBV) and BKvirus, papillomavirus. Moreover, BCV is an easy-to-use and novel highly active antimultiviral agent
that can reduce the risk of nephrotoxicity, which is a serious side effect of CDV. SymBio entered into
an exclusive global license agreement with Chimerix Inc. (Headquarters: Durham, NC, "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 humanindications, excluding the prevention and treatment of orthopox infections (which includes smallpox
and monkeypox). 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 ofthe 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 sizefor organ transplantation is large, and Asia, including the Chinese market.

2About SymBio Pharmaceuticals Limited
SymBio Pharmaceuticals Limited was established in March 2005 by Fuminori Yoshida whopreviously 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., SymBio
Pharma USA, Inc. (Headquarters: Durham, North Carolina, 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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