Beam Therapeutics Announces Clearance of Clinical Trial Authorisation Application for BEAM-302 for the Treatment of Alpha-1 Antitrypsin Deficiency (AATD)

Initiation of Phase 1/2 Trial of BEAM-302 in AATD Expected in First Half of 2024

CAMBRIDGE, Mass., March 26, 2024 (GLOBE NEWSWIRE) -- Beam Therapeutics Inc. (Nasdaq: BEAM), a biotechnology company developing precision genetic medicines through base editing, today announced the clearance of its clinical trial authorisation (CTA) application by the United Kingdom (UK) Medicines and Healthcare Products Regulatory Agency for BEAM-302, an in vivo base editor, as a potential treatment for patients with alpha-1 antitrypsin deficiency (AATD).

“The clearance of our first CTA is an important step in the advancement of our global Phase 1/2 study of BEAM-302, a potentially best-in-class, liver-targeting in vivo base editor designed to correct the PiZ mutation, which is the most common gene variant associated with severe AATD,” said Giuseppe Ciaramella, Ph.D., president of Beam. “AATD is an inherited genetic condition that can cause serious lung and liver disease, which can lead to significant debility and reduced life expectancy for patients. Preclinical data demonstrated the ability of BEAM-302 to significantly increase levels of corrected and functional alpha-1 antitrypsin (AAT) and reduce the mutant PiZ AAT protein in in vivo rodent disease models at clinically relevant doses. These findings support the potential of BEAM-302 to efficiently correct the disease-causal PiZ mutation after a single dose and potentially address both the liver and lung disease associated with AATD.”

The Phase 1/2 clinical trial is an open-label, dose-escalation study that will evaluate the safety, pharmacodynamics, pharmacokinetics and efficacy of BEAM-302 initially in patients with AATD-associated lung disease. The study design includes a dose exploration portion followed by a dose expansion portion to identify the optimal dose to take forward in a pivotal study. The company expects to initiate the Phase 1/2 trial of BEAM-302 in the UK in the first half of 2024.

About BEAM-302
BEAM-302 is a liver-targeting lipid-nanoparticle (LNP) formulation of base editing reagents designed to precisely correct the PiZ mutation, a single-letter genetic error found in the majority of severe homozygous patients (PiZZ) living with AATD. A one-time A-to-G correction of the PiZ mutation with Beam’s adenine base editor has the potential to simultaneously reduce the aggregation of mutant, misfolded AAT protein that causes toxicity to the liver and increase circulating levels of corrected and functional AAT protein, thus addressing the underlying pathophysiology of both the lung and liver disease. In addition, the reduction in circulating PiZ aggregates (i.e., polymers) has the potential to further minimize lung inflammation and dysfunction. Importantly, because the native AAT gene would be corrected in its normal genetic location, AAT levels are anticipated to increase physiologically in response to inflammation or infection, a critical aspect of AAT’s normal function to regulate the body’s inflammatory response, which would not occur with currently approved protein replacement therapies. Correction of the PiZ mutation is expected to be durable based on preclinical evidence to date.