PeproMene Bio has completed the first dose cohort of its Phase I clinical trial of PMB-CT01, a BAFFR-targeted, autologous CAR T cell therapy, to treat relapsed or refractory B-cell Non-Hodgkin Lymphoma (r/r B-NHL).

The study is being carried out at the City of Hope, which is claimed to be one of the largest cancer research and treatment organisations in the US.

Administration of 50x10⁶ PMB-CT01 was well tolerated in the first cohort, with no dose-limiting toxicity.

Out of the three treated patients, all of them experienced grade 1 cytokine release syndrome and two experienced grade 1 immune effector cell-associated neurotoxicity syndrome, with complete recovery.

Prior to enrolment in the PMB-CT01 trial, two subjects showed progression in mantle cell lymphoma following treatment with conventional CD19 CAR T-cell therapy.

One month after the treatment, the overall response rate was 100%, with two complete response and one partial response.

PeproMene Bio COO Hazel Cheng said: “Although still in the early stage, we are encouraged by the initial observation of acceptable safety and preliminary efficacy in the first dose cohort of PMB-CT01 treated B-NHL patients.

“All three treated patients (two progressed after CD19 CAR T therapy and one with CD19/CD20 negative lymphoma) responded to PMB-CT01 treatment.

“These clinical outcomes are consistent with City of Hope preclinical research data published in Science Translational Medicine in 2019, which showed that PMB-CT01 (BAFFR-CAR T Cells) could overcome CD19 antigen loss in B-cell malignancies.”

With the completion of the first dose cohort, the company plans to initiate the second cohort.

PeproMene has licensed intellectual property relating to the cell therapy from the City of Hope.

The company is also engaged in developing BAFFR-CAR natural killer cells and BAFFR Bispecific T Cell Engager cells.