September 16, 2021

BrightPath Presents Preclinical Data on a CD73 antagonist antibody
at ESMO 2021
-New data from pre-clinical development of CD73 antagonist antibody, BP1200
that ameliorates tumor microenvironment.

Tokyo, Japan - September 16, 2021/ -- BrightPath Biotherapeutics (TSE Mothers: 4594.T,“BrightPath”), a clinical-stage biotech company dedicated to the discovery and development ofnovel immunotherapies, today announced data presentations from its immuno-oncology
pipeline at the European Society for Medical Oncology (ESMO) 2021 Congress, Sept. 16-21,
2021. The abstract featuring data on a CD73 antagonist therapeutic antibody, BP1200 will beshared in a virtual poster viewing session.
BrightPath’s abstract is as follows:
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.
BP1200 is a humanized antibody that is a potentially best-in-class immune checkpoint inhibitor
targeting CD73 expressed on tumor and immune cells. CD73 is a cell surface enzyme that isexpressed on tumor cells and converts extracellular adenosine monophosphate (AMP) into
immunosuppressive adenosine. Adenosine production inhibits T cell and NK cell cytotoxicity,
cytokine production, and proliferation as well as suppression of antigen presenting cells andmacrophage M2 polarization, which enables tumor growth and disease progression. BP1200
ameliorates the suppressive tumor microenvironment by attenuating adenosine production andreestablishes a broad anti-tumor response mediated by tumor infiltrating T cells which includes
enhancement of proliferation, cytokine production, and cytotoxicity of T cells. BP1200 incombination with other complementary immune pathways such as PD-1/PD-L1, is a key
strategy to enhance the anti-tumor cytotoxic potential of immunotherapy.
Kenichi Nagai, CEO of BrightPath, said: “We are very excited to the data showing that BP1200
is a potentially best-in-class immunotherapy antibody. This presentation supports theCompany’s focus on developing antibodies that target the immuno-suppressive tumor
microenvironment. The mechanism of immunosuppression remains largely unknown, and weare committed to advancing the science to address ongoing and unmet therapeutic needs.”
More detailed results will be shared as a poster presentation once the conference begins on
September 16 at 8:30 a.m. CEST.

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About BrightPath:
BrightPath Biotherapeutics is an immuno-oncology focused biotech company dedicated to
improving 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 isan 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 antibody
engineering. 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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