US-based biotechnology company ImmPACT Bio has dosed the first patient in its Phase I/II clinical trial of IMPT-314 for relapsed or refractory (R/R) aggressive B-cell lymphoma.

IMPT-314 is a bispecific CD19/CD20 chimeric antigen receptor (CAR) T-cell therapy that makes use of a potent bispecific CAR and 4-1BB costimulatory domain.

The multicentre, open-label trial will assess the drug's efficacy and safety in patients with R/R aggressive B-cell lymphoma.

Its first phase will include both CAR T-experienced and CAR T-naïve patients.

ImmPACT Bio expects to report Phase I safety and preliminary efficacy findings from the trial in the first half of next year.

The US Food and Drug Administration (FDA) previously granted fast track designation to the CAR T-cell therapy to treat R/R aggressive B-cell lymphoma.

ImmPACT Bio chief medical officer Jonathan Benjamin said: “We are pleased to have treated the first patient with IMPT-314 and build on the clinical evidence from the ongoing investigator-led study of this dual-targeted CD19/CD20 CAR T-cell therapy.

“We believe IMPT-314 may improve tolerability and durability of responses in patients with B-cell lymphomas and therefore has best-in-class potential.

“Safety and efficacy data from this Phase I/II study will determine the recommended Phase II dose for IMPT-314 and inform on potential cohort expansion opportunities.”

In a Phase I study led by an investigator from the University of California, the bispecific CAR construct underlying IMPT-314 was shown to provide an overall response rate of 91% in R/R non-Hodgkin lymphoma patients.

A median progression-free survival of 18.2 months was also reported in that trial.

Based in Los Angeles, California, ImmPACT Bio aims to discover 'transformative' CAR-T cell therapies to treat cancer and autoimmune diseases.

The company’s logic gate-based CAR T-cell platforms are designed to prevent antigen escape, overcome the immunosuppressive tumour microenvironment and deplete pathogenic B cells.