November 10, 2022

BrightPath to Update the Pre-clinical Data of BP1210 and BP1212
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 the pre-clinical data on a novel
Bispecific antibodies that block TIM-3 (BP1210) and a novel Bispecific antibodies that blockTIM-3 and CD39 (BP1212) at the Society for Immunotherapy of Cancer Annual Meeting(SITC 2022, November 8-12, Boston).
The presentation is available on the websites of BrightPath
BrightPath’s abstract is as follows:
Title: Bispecific antibodies that block TIM-3 and CD39 induce anti-tumor efficacy and immune
response by blocking multiple suppressive mechanisms.
(Abstract number:1364)
The presentation describes:•
BP1210 and BP1212 are bispecific antibodies developed using next-generation
antibody engineering technology and exert their antitumor effects bysimultaneously recognizing and inhibiting immunosuppressive molecules, TIM-3and CD39.
•BP1210 strongly activates cytotoxic T cells that attack cancer cells, and enhances
its anti-tumor effects. By the bispecificity, significantly higher anti-tumor activity
was achieved than other anti-TIM-3 antibodies (monospecific antibodies) underclinical development.

•BP1212 exerts anti-tumor effects by targeting CD39 and TIM-3-positive cells andblocking the immunosuppressive functions of CD39 and TIM-3. By the dual binding
to targets, BP1212 strongly inhibits target molecules with higher specificity inrecognition of target cells. Simultaneous dual binding and inhibition enhances andmaintains high antitumor activity of cytotoxic T cells more than either monoclonal
antibody alone.

TIM-3, an immune checkpoint molecule, is expressed on activated T cells and dendritic cells
that play a central role in anti-tumor immunity. TIM-3 attenuates the function of immune cellsby responding with multiple molecules including phosphatidylserine, galectin-9, HMGB1,CEACAM1, etc. released by cancer cells for immunosuppression and escape. Although theinnate function of TIM-3 is to control excessive immune responses that causes inflammationand tissue damages, it also suppresses anti-tumor immune response in cancer patients. TIM3 antibodies in clinical development to date have limited anti-tumor efficacy due to their monospecificity, which does not sufficiently block the immunosuppressive function of TIM-3 triggeredby multiple ligands. Using bispecific antibody technology, we have developed a biparatopic
antibody, BP1210, which strongly inhibits immune-suppressive signals by TIM-3
BP1212 is a bispecific antibody that simultaneously inhibits TIM-3 and CD39. TIM-3 and CD39

are induced for self-suppression in cytotoxic T cells that attack cancer cells, but cancer cells
abuse these molecules for immune escape and proliferation. BP1212 robustly enhances thecytotoxic activity of intra-tumoral T cells against cancer cells by inhibiting the function of these
two molecules and releasing the brake of tumor immunity. In addition, BP1212 is a highly
engineered bispecific antibody with enhanced target specificity and inhibiting potential througha precise molecular design that allows simultaneous recognition of two target molecules.
About BrightPath:
BrightPath is a clinical stage biopharmaceutical company focused on the development of novel
cancer immuno-therapies to transform cancer treatment for refractory or progressive cancers
that cannot be treated with conventional standard therapies. BrightPath is actively involved indeveloping 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 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 involverisks and uncertainties that could cause actual results to differ materially from those
discussed in the forward-looking statements. These forward-looking statements speak only
as of the date of this press release and BrightPath assumes no duty to update forward-looking
statements, except as may be required by law.
Investor and Media Contact:+81-3-5840-7697
irpr@brightpathbio.com
www.brightpathbio.com/english/index.html