Beam Doses First Patient in Phase 1/2 Trial of Base Edited CAR-T Cell Therapy

Rare Daily Staff

Beam Therapeutics, which is developing precision genetic medicines through base editing, said that the first patient in August was treated with BEAM-201, a quadruplex-edited allogeneic CAR-T cell investigational therapy.

BEAM-201 is being evaluated in a phase 1/2 clinical study for the treatment of relapsed/refractory T-cell acute lymphoblastic leukemia/T-cell lymphoblastic lymphoma (T-ALL/T-LL), a severe disease affecting children and adults.

It is a major milestone for the company as the first patient in the United States to receive a base editing therapeutic.

“We believe that the full therapeutic potential of CAR-T therapies, including the ability to utilize an allogeneic source of T cells, will only be unlocked through higher levels of cellular engineering enabled by multiple simultaneous genetic edits,” said John Evans, CEO of Beam.

Beam believes base editing is especially well-suited to the challenge, as it is designed to deliver highly efficient multiplex edits in cells without the double stranded breaks that can lead to frequent chromosomal rearrangements and loss of cell viability.

“BEAM-201, to our knowledge the first quadruplex-edited cell therapy candidate in clinical development, is an allogeneic CAR-T cell investigational therapy with the potential to make a substantial impact for patients diagnosed with challenging T-cell cancers who have limited treatment options,” said Evans.

The ongoing phase 1/2 trial of BEAM-201 is a multicenter, open-label study evaluating safety and efficacy in patients with relapsed/refractory T-ALL/T-LL. T-ALL/T-LL is a highly aggressive blood cancer arising from malignant transformation of T cell precursors that has few treatment options.

The primary objectives of the phase 1 portion of the trial are the assessment of safety, tolerability, and identification of the recommended phase 2 dose and lymphodepletion regimen. Key safety endpoints for the trial include treatment-emergent and treatment-related adverse events, and key efficacy endpoints include proportion of patients with complete or partial responses, proportion eligible for hematopoietic stem cell transplant, and proportion achieving minimal residual disease negative status.

BEAM-201 is a quadruplex base-edited, anti-CD7 allogeneic chimeric antigen receptor T cell (CAR-T) under clinical investigation for the treatment of CD7+ relapsed/refractory T-cell acute lymphoblastic leukemia/T-cell lymphoblastic lymphoma. Multiplexed base editing is designed to eliminate expression of the CD7, TRAC, PDCD1 and CD52 genes. This approach has the potential to reduce fratricide, graft-versus-host disease, and CAR-T cell exhaustion and to enable BEAM-201 cells to evade anti-CD52 lymphodepleting agents and enable use of an allogeneic cell source.

Photo: John Evans, CEO of Beam