September 24, 2021

BrightPath’s abstract on a CD73 antagonist antibody
wins Best Poster Award at ESMO 2021

Tokyo, Japan - September 24, 2021/ -- BrightPath Biotherapeutics (TSE Mothers: 4594.T,“BrightPath”), a clinical-stage biotech company dedicated to the discovery and development ofnovel immunotherapies, today announced its data presentations “A novel therapeutic antibody
against CD73 that ameliorates the tumor microenvironment and improves the efficacy of cancer
immunotherapy” won the Best Poster Award at the European Society for Medical Oncology(ESMO) 2021 Congress, Sept. 16-21, 2021.
ESMO 2021 has offered massive international visibility for scientific research, while involving
all key oncology stakeholders: researchers, clinicians, cancer nurses, industry partners, patientadvocates and media. We are encouraged by achieving the award from approximately 1,800
presentations and obtaining an endorsement of potentiality of BP1200 as a novel best-in-classimmunotherapy antibody to proceed with further development.
ESMO Congress 2021, Sept. 16-21, has also prompted the oncology community to look atCD73 as a promising target of immunotherapy. AstraZeneca is leading the development of antiCD73 antibody, oleclumab (MEDI9447), and announced an interim analysis of the Phase II
Coast trial showing the addition of oleclumab to Imfinzi, AstraZeneca’s own anti-PD-L1 antibody,
boosted response rates and progression-free survival.
Our new data presentation includes BP1200 inhibited tumor growth in combination with antiPD-L1 or anti-PD-1 antibody in murine models. BP1200 is a humanized, high affinity
antagonistic antibody for CD73. BP1200 suppresses CD73 function in tumor by inhibiting
enzymatic activity of CD73 as well as by inducting internalization of cell surface CD73. Thereby
BP1200 exhibits high efficacy in T cell proliferation and cytotoxicity on tumor cells. BP1200 in
combination with other complementary immune pathways such as PD-1/PD-L1, is a key
strategy to enhance the anti-tumor cytotoxic potential of immunotherapy.
This award supports BrightPath’s focus on developing antibodies that target the immunosuppressive tumor microenvironment. We are committed to advancing the science to addressongoing and unmet therapeutic needs.

BrightPath’s abstract is as follows:1

Title: A novel therapeutic antibody against CD73 that ameliorates the tumor
microenvironment and improves the efficacy of cancer immunotherapy. (987P)
Toshifumi Obonai, Ph.D., Senior Scientist, Translational Research at BrightPath Biotherapeutics
The abstract for this presentation is available on the ESMO website.
The ESMO Congress 2021 presentation and press release are available on the Company’s
website.

About BrightPath:
BrightPath Biotherapeutics is an immuno-oncology focused biotech company dedicated toimproving treatment and clinical outcomes for patients through cancer vaccine, therapeutic
antibodies, and cell therapy that harness the immune system to fight cancer.
BrightPath’s clinical-stage product, GRN-1201 is a new cancer vaccine in phase 2 trial inpatients with melanoma and lung cancer in US. BP2201 in-collaboration with RIKEN, Japan is
an iPS (induced pluripotent stem cell)-derived NKT therapy and the phase 1 trial is currently
ongoing in Japan.
BrightPath’s broad pipeline of immunotherapy includes several potentially first-in-class and bestin-class clinical and preclinical candidates in cancers with high unmet medical need.
BrightPath has been a pioneer in immunotherapy by cancer vaccine and has expanded its
expertise in the tumor microenvironment and immune cell development as well as antibodyengineering. This innovative approach has resulted in a diversified proprietary portfolio ofcancer vaccine, therapeutic antibody, and immune-cell therapy.
Based in Tokyo, Japan, BrightPath is listed on Tokyo Stock Exchange in Japan. For more
information, visit www.brightpathbio.com.
Forward-Looking Statements:
This news release contains forward-looking statements that are based on the current
expectations and beliefs of BrightPath. All statements, other than statements of historical fact,
are statements that could be deemed forward-looking statements. BrightPath cautions thatthese forward-looking statements do not guarantee our future financial results but involve risks
and uncertainties that could cause actual results to differ materially from those discussed in theforward-looking statements. These forward-looking statements speak only as of the date of thispress release and BrightPath assumes no duty to update forward-looking statements, except as
may be required by law.
Investor and Media Contact:
Takashi Hamamoto
Director of Corporate Management+81-3-5840-7697
irpr@brightpathbio.com
www.brightpathbio.com

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