PeproMene Bio, Inc. Announced Complete Response of The First Patient Treated in Its B-cell Non-Hodgkin Lymphoma (B-NHL) Phase 1 Clinical Trial of PMB-CT01 (BAFFR-CAR T Cells) at City of Hope

IRVINE,Calif.,Dec. 21,2022 -- PeproMene Bio,Inc.,a clinical-stage biotech company developing novel therapies to treat cancers and immune disorders,today announced that the first patient treated in its phase 1 relapsed or refractory B-cell Non-Hodgkin Lymphoma (r/r B-NHL) clinical trial of PMB-CT01 (BAFFR-CAR T Cells) has reached Complete Response at 1-month post treatment. The trial is taking place at City of Hope,one of the largest cancer research and treatment organizations in the United States.

During the first month of treatment,the patient only experienced low grade treatment emergent toxicities,including grade 1 cytokine release syndrome ("CRS") with full recovery and no immune effector cell-associated neurotoxicity syndrome ("ICANS"). "This mantle cell lymphoma patient has been refractory to several prior lines of treatment including chemoimmunotherapy,BTK inhibitor,Venetoclax,and CD19-CAR T therapy. We are pleased to see a deep complete remission which is minimal residual disease negative," said Elizabeth Budde,M.D.,Ph.D.,City of Hope associate professor,Division of Lymphoma,Department of Hematology & Hematopoietic Cell Transplantation and the principal investigator of this single-center,dose escalation trial (NCT05370430).

"Despite high initial efficacy of CD19-CAR T cell treatment for B-cell lymphoma and leukemia,there is a significant unmet medical need for those patients who unfortunately relapse," said Larry W. Kwak,vice president and deputy director of City of Hope's Comprehensive Cancer Center and PeproMene's scientific founder and compensated chair of its Scientific Advisory Board. Kwak has an equity interest in PeproMene. "As BAFF-R is a novel tumor target for B-cell malignancies,I am hoping BAFFR-CAR T therapy will offer a clinically meaningful,new option for those patients."

"The acceptable safety profile and early complete response of our first B-NHL patient treated PMB-CT01 is an unprecedented milestone in the development and evaluation of PMB-CT01. These initial clinical outcomes are supported by City of Hope preclinical research data published in Science Translational Medicine in 2019,which showed that PMB-CT01 (BAFFR-CAR T Cells) can overcome CD19 antigen loss in B-cell malignancies," said Hazel Cheng,COO of PeproMene.

About PMB-CT01

PMB-CT01 is a first-in-class BAFFR-targeted,autologous CAR T cell therapy. BAFF-R (B Cell Activating Factor Receptor),a tumor necrosis factor (TNF) receptor superfamily member,is the main receptor for BAFF expressing almost exclusively on B cells. Since BAFF-R signaling promotes normal B-cell proliferation and appears to be required for B-cell survival,it is unlikely tumor cells could escape immune responses via loss of BAFF-R antigen. This unique characteristic makes BAFF-R CAR T therapy a great potential treatment of B cell malignancies. BAFF-R CAR-T was constructed using the anti-BAFF-R scFv (single-chain fragment variable) antibodies with the 2nd generation signaling domains containing CD3ζ and 4-1BB. Our research has found that BAFFR-CAR T cells kill human lymphomas and leukemias in vitro as well as in animal models. PeproMene has licensed intellectual property relating to PMB-CT01,from City of Hope.

About PeproMene

PeproMene is a clinical-stage biotech company in Irvine,California developing novel therapies to treat cancers and immune disorders. PeproMene's lead candidate,PMB-CT01 (BAFFR-CAR T Cells) is currently being investigated to treat relapsed and refractory B-cell acute lymphoblastic leukemia (B-ALL; NCT04690595) and B-cell Non-Hodgkin's lymphoma (B-NHL; NCT05370430) in phase 1 clinical trials. PeproMene is also developing BAFFR Bispecific T Cell Engager and BAFFR-CAR NK cells. For more information,contact Hazel Cheng,Ph.D. of PeproMene Bio Inc. at hazel.cheng@pepromenebio.com or visit www.pepromenebio.com.