September 16, 2021

BrightPath Presents New Data on Personalized Neoantigen
Vaccine Platform at ESMO 2021
-New data highlighting scientific advancements in immune-checkpoint antibody-directed
personalized neoantigen vaccine, BP1209.

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 new platform for personalized neoantigen vaccine,
BP1209 will be shared in a virtual poster viewing session.
BrightPath’s abstract is as follows:
Title: A new platform of personalized neoantigen cancer vaccines directed by checkpoint
inhibitor antibodies to improve cancer immunity. (1005P)
Yuji Mishima, Ph.D., Principal Scientist, Discovery Pharmacology at BrightPath Biotherapeutics
The abstract for this presentation is available on the ESMO website.
BP1209 is a proprietary, advanced cancer vaccine which targets tumor-specific neoantigens forthe personalized treatment of cancer patients. The BP1209 vaccine is delivered as a molecularcomplex of patient-specific neoantigen peptides and immune-checkpoint inhibitor antibody suchas anti-PD-L1 and anti-CD40 antibodies. The antibody directs the vaccine complex to dendritic
cells (DCs), and enhances the cellular uptake of vaccine as well as the antigen-specific T cellpriming by suppressing PD-1/PD-L1 signaling or CD40 activation. The neoantigen peptides
consists of three modules: HLA-class I and -class II neoantigen epitopes, and an IgG-binding
motif. The peptides non-covalently bind Fc domain of IgG, and self-assemble the antibodyvaccine complex without any chemical reaction which enables individual synthesis andmanufacturing fully personalized neoantigen vaccine. In this poster, authors demonstrate
BP1209 strongly enhances antigen-specific immune responses and improves antitumor efficacy
using cancer neoantigen. BrightPath has developed in-house bioinformatic algorithms to identify
highly immunogenic neoantigens from cancer patients. The new vaccine platform of BP1209 incombination with BrightPath’s algorism to identify high quality neoantigens provides an idealoption to improve neoantigen vaccine therapy.
Kenichi Nagai, CEO of BrightPath, said: “To date, we have developed new platform forpersonalized neoantigen vaccine that is potentially best-in-class immunotherapy agent. We arevery encouraged by these preclinical results that confirms our hypothesis that BP1209 vaccine,which effectively induces potent T cell responses, synergizes with immune-checkpoint inhibitors
such as anti-PD-L1. The concept of the new vaccine platform is realized by our unique1technology to bind an off-the-shelf antibody and fully personalized vaccines.”More detailed results will be shared as a poster presentation once the conference begins on
September 16 at 8:30 a.m. CEST.
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 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 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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