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RecruitingNCT06735755Updated Dec 15, 2025

A Phase 1/2, Dose-Exploration Study to Evaluate the Safety and Efficacy of BEAM-301 in Patients With Glycogen Storage Disease Type Ia (GSDIa)

A Phase 1/2 interventional study of BEAM-301: Single dose of BEAM-301 administered by IV in Glycogen Storage Disease Type Ia, sponsored by Beam Therapeutics Inc.. Recruiting at 3 sites in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-12-15.

Sponsored by Beam Therapeutics Inc. · Phase 1/2, Interventional, and Treatment

Phase
Phase 1/2
Study type
Interventional
Enrollment
36
Allocation
Not applicable
Ages
18 Years and older
Sex
All
01

Study summary

This is a Phase 1/2, multicenter, open-label, single-ascending-dose study to evaluate the safety, tolerability, and efficacy of BEAM-301 in adult patients with GSDIa homozygous or compound heterozygous for the G6PC1 c.247C>T (p.R83C) variant and to determine the optimal biological dose.

02

Conditions studied

  • Glycogen Storage Disease Type Ia

Keywords

  • GSDIa
  • GSD1a
03

Who can participate

Ages eligible
18 Years and older
Sexes eligible
All
Accepts healthy volunteers
No

Inclusion criteria

  1. Males or females age ≥18 years of age at the time of consent.
  2. Diagnosis of GSDIa and homozygous or compound heterozygous for the G6PC1 c.247C>T (p.R83C) variant (confirmed by genetic testing).
  3. History of at least 1 episode of hypoglycemia \<60 mg/dL within the 2 years prior to signing the ICF.

Exclusion criteria

Exclusion Criteria:

  1. Liver transplant recipient/on waiting list for liver transplant or known history of liver cirrhosis.
  2. Presence of liver adenoma >5 cm in size based on liver MRI or liver ultrasound performed at screening or within 6 months prior to screening.
  3. Presence of liver adenoma >3 cm and ≤5 cm with a documented annual growth rate of ≥0.5 cm per year.
  4. Have aspartate transaminase or alanine transaminase >upper limit of normal (ULN).
  5. Total bilirubin levels >ULN; if documented Gilbert's Syndrome, total bilirubin >2 × ULN.
  6. Previous treatment with any cell-, gene-, or viral vector-derived therapy Hospitalization for management of hypoglycemia within 4 weeks prior to signing the ICF.
  7. Have triglycerides >1000 mg/dL or a history of pancreatitis or a history of acute pancreatitis within 5 years that does not have a known and corrected etiology (eg, cholecystectomy for gallstone pancreatitis).
04

Study design

Phase
Phase 1 / Phase 2
Primary purpose
Treatment
Allocation
Not applicable
Intervention model
Sequential assignment
Masking
None (open label)
Enrollment
36 participants (estimated)

Study arms

  • Experimental
    BEAM-301

    BEAM-301 consists of adenine base editor messenger ribonucleic acid (mRNA) and single guide ribonucleic acid (gRNA) formulated in lipid nanoparticles (LNPs) for intravenous (IV) administration.

    Drug: BEAM-301: Single dose of BEAM-301 administered by IV

Interventions

  • DrugBEAM-301: Single dose of BEAM-301 administered by IV

    BEAM-301 is designed to correct the G6PC1 c.247C\>T allele via an A:T-to-G:C base-pair substitution, resulting in restoration of G6Pase-α catalytic activity.

05

What researchers measure

Primary outcomes

  1. To evaluate the safety and tolerability of BEAM-301 in patients with GSDIa with a G6PC1 c.247C>T (p.R83C) variant by measuring incidence of treatment-emergent adverse events (TEAEs) including serious adverse events (SAEs) and dose-limiting toxicities (DL

    Time frame: BEAM-301 administration through month 24

Secondary outcomes

  1. Absolute and change from baseline in time to hypoglycemia or metabolic decompensation during a controlled fasting challenge

    Time frame: Baseline to month 24

  2. Changes from baseline in starch supplementation dose

    Time frame: Baseline to month 24

  3. Level of serum glucose and metabolic parameters (lipid profile and uric acid) over time

    Time frame: Baseline to month 24

  4. BEAM-301 PK parameters (Cmax)

    Time frame: Baseline to month 24

  5. BEAM-301 PK parameters (AUC)

    Time frame: Baseline to month 24

  6. BEAM-301 PK parameters (half-life)

    Time frame: Baseline to month 24

06

Study locations

3 of 3 sites recruiting
  • Clinical Study Site
    Orange, California 92868, United States
    Recruiting
  • Clinical Study Site
    Farmington, Connecticut 06030, United States
    Recruiting
  • Clinical Study Site
    Houston, Texas 77030, United States
    Recruiting
07

Registry details

Key details

Study ID
NCT06735755
Lead sponsor
Beam Therapeutics Inc.
Responsible party
Sponsor
First posted
Dec 16, 2024
Start date
Dec 6, 2024
Primary completion
Dec 30, 2027 (estimated)
Completion
Dec 30, 2027 (estimated)
Last update
Dec 15, 2025

Study contacts

Medical Information
Contact
clinicalinfo@beamtx.com
857-327-8641

Oversight

FDA-regulated drug
Yes
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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