November 10, 2022

BrightPath to Update the Pre-clinical Data of BP1202
at SITC 2022
Tokyo, Japan - November 10, 2022/ -- BrightPath Biotherapeutics (TSE Growth 4954), aclinical- stage biopharmaceutical company focused on developing novel cancer
immunotherapeutics, today announced a presentation of pre-clinical data on a novel antiCD39 antibody (BP1202) at the Society for Immunotherapy of Cancer Annual Meeting (SITC2022, November 8-12, Boston).
The presentation is available on the websites of BrightPath

BrightPath’s abstract is as follows:
Title: BP1202-NF2, a novel ADCC-enhancing CD39 antibody, induces destruction ofregulatory T cells and enhances cytotoxic T lymphocytes induction（Abstract number:1221）
The presentation describes:• BrightPath has developed BP1202-NF2, a novel functional antibody targeting CD39,
with enhanced antibody-dependent cellular cytotoxicity (ADCC) in addition to CD39
enzyme inhibition activity• CD39 was highly expressed by regulatory T cells (Treg) and exhausted T cells intumor tissues of the patients with non-small cell lung cancer• BP1202-NF2 highly promoted the induction of antigen-specific cytotoxic T cells(induction of acquired immunity) by eliminating Tregs via ADCC activity• Peripheral blood lymphocytes with acquired immunity induced by BP1202-NF2strongly suppressed the proliferation of lung cancer cells
CD39 is an enzyme involved in extracellular adenosine triphosphate (eATP) metabolism, andadenosine produced by eATP metabolism is known to cause immunosuppressive conditionsin the tumor microenvironment (TME). CD39 is highly expressed on not only tumor cells but
immune cells such as exhausted T cells and regulatory T cells (Treg) in the tumor
microenvironment (TME). It has been reported that high CD39 expression in the TME isassociated with poor prognosis in many hematologic and solid tumors.
BP1202-NF2 is a humanized therapeutic antibody that inhibits CD39 enzymatic activity withhigh specificity and binding affinity to CD39 and selectively eliminates CD39-highlyexpressing immunosuppressive cells through an enhanced ADCC activity. The novel tumorimmunoregulatory antibody suppresses adenosine production and simultaneously eliminates
immunosuppressive cells in TME, which leads to abolish the immunosuppression of TME andenhance anti-tumor immunity. In this presentation, we experimentally demonstrated that
BP1202-NF2 potently eliminates immune-suppressive Tregs and exhibits anti-tumor activity

by enhancing the cytotoxic activity of lymphocytes.
Tregs are known to suppress the immune response and tumor-infiltrating Tregs have beenreported to be a poor prognostic factor in many cancers and considered to be a key target toovercome the cancer immune escape in TME. In this presentation, we have shown that
BP1202-NF2 potently eliminated Tregs to abolish immunosuppression of TME, and it isexpected that BP1202-NF2 will be a promising treatment option for clinical practice.
About BrightPath:
BrightPath is a clinical stage biopharmaceutical company focused on the development ofnovel cancer immuno-therapies to transform cancer treatment for refractory or progressive
cancers that cannot be treated with conventional standard therapies. BrightPath is actively
involved in developing cell therapies currently in clinical trials, immunomodulatory antibodies
and new drug targeted at cancer specific neoantigens.
For more information, visit www.brightpathbio.com/english/index.html.
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 historicalfact, are statements that could be deemed forward-looking statements. BrightPath cautions
that these 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 the forward-looking statements. These forward-looking statements speak onlyas of the date of this press release and BrightPath assumes no duty to update forwardlooking statements, except as may be required by law.
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www.brightpathbio.com/english/index.html