Beam Therapeutics Inc. outlined anticipated 2022 milestones across its ex vivo programs targeting editing of hematopoietic stem cells (HSCs) and T cells and in vivo programs targeting editing of liver cells leveraging lipid nanoparticles (LNPs) for delivery. Updates include that the company has selected its fourth development candidate and first in vivo base editing candidate, BEAM-301, which aims to correct the R83C mutation for the potential treatment of patients with glycogen storage disorder Ia (GSDIa). BEAM-101 is a patient-specific, autologous HSC investigational therapy, which incorporates base edits that are designed to mimic single nucleotide polymorphisms seen in individuals with hereditary persistence of fetal hemoglobin.

BEAM-101 aims to potentially alleviate the effects of mutations causing sickle cell disease (SCD) or beta-thalassemia by leading to increases in fetal hemoglobin, which inhibits hemoglobin S (HbS) polymerization. The BEACON-101 trial is a Phase 1/2 clinical trial designed to assess the safety and efficacy of BEAM-101 for the treatment of SCD. The trial is expected to include an initial “sentinel” cohort of three patients, treated one at a time to confirm successful engraftment, followed by dosing in up to a total of 45 patients.

Beam has begun site selection and the institutional review board approval processes for the BEACON-101 trial and plans to enroll the first subject in the second half of 2022. BEAM-102 is designed to treat SCD by directly editing the causative HbS point mutation to recreate a naturally occurring normal human hemoglobin variant, HbG-Makassar. The Makassar variant has been reported to have the same function as the more common HbA variant and does not cause SCD.

Beam plans to submit an investigational new drug (IND) application for BEAM-102 in the second half of 2022.