PeproMene Bio, Inc. Announces Complete Remission of the Cohort 1 First Patient Treated for Relapsed and Refractory B-cell Acute Lymphoblastic Leukemia (B-ALL) in the Phase 1 Clinical Trial of PMB-CT01 (BAFFR-CAR T Cells) at City of Hope

IRVINE, Calif.Jan. 18, 2024 /PRNewswire/ — PeproMene Bio, Inc., a clinical-stage biotech company developing novel therapies to treat cancers and immune disorders, today announced that the cohort 1 first patient treated in its Phase 1 relapsed or refractory B-cell acute lymphoblastic leukemia (r/r B-ALL) clinical trial of PMB-CT01 (BAFFR-CAR T Cells) has reached complete remission at one-month post treatment.

This result adds to the presentation of PeproMene Bio’s clinical trial of PMB-CT01 in relapsed/refractory non-Hodgkin’s lymphoma at last month’s American Society of Hematology annual meeting in San Diego. The trial results, presented by Elizabeth Budde, M.D., Ph.D., City of Hope associate professor, Division of Lymphoma, Department of Hematology & Hematopoietic Cell Transplantation, generated considerable excitement because all three patients achieved durable complete remissions with minimal toxicity (https://ash.confex.com/ash/2023/webprogram/Paper183032.html).

The trials are taking place at City of Hope, one of the largest cancer research and treatment organizations in the United States, which also developed the therapy.

During the first month of treatment, the patient only experienced low grade treatment emergent toxicities, including grade 1 cytokine release syndrome (“CRS”) resolved without intervention, and no immune effector cell-associated neurotoxicity syndrome (“ICANS”).

“We are excited about the treatment outcomes as this patient had a relapsed B-cell ALL after prior treatment with chemotherapy and blinatumomab. His relapsed disease was both CD19- and CD22-negative, implying very limited available therapeutic options for him,” said Ibrahim T. Aldoss, M.D., City of Hope associate professor, Department of Hematology & Hematopoietic Cell Transplantation and the principal investigator of this single-center, dose escalation with expansion trial (NCT04690595).

“He tolerated the treatment of BAFFR-CAR T Cells really well with only minimal and anticipated toxicities.  Additionally, he achieved complete remission and clearance of minimal residual disease (MRD), indicating an excellent response to this effective therapy.”

“PeproMene has achieved an exceptional milestone in the development and evaluation of PMB-CT01 with the observation of the acceptable safety profile and complete response in this PMB-CT01 treated B-ALL patient. These initial clinical outcomes are supported by City of Hope preclinical research data published in Science Translational Medicine in 2019, which shows BAFFR-CAR T Cells can effectively eliminate various B-cell malignancies including B-ALL and different subtypes of B-lymphomas,” said Hazel Cheng, Ph.D., COO of PeproMene.

PMB-CT01 was invented by the laboratory of Larry W. Kwak, M.D., Ph.D., 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.

City of Hope holds an interest in the investigational compound ‘BAFFR(EQ)BBζ/EGFRt+ CAR T Cells’, the compound being studied in this research.

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 BAFFR-CAR T therapy a great potential treatment of B-cell malignancies. BAFFR-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.