BeCoMe-9: A Clinical Study of BE-101 for the Treatment of Adults With Moderately Severe or Severe Hemophilia B

The BeCoMe-9 Study (BE-101-01) is a Phase 1/2, first in human, multi-center, open-label, dose-escalation study to evaluate the safety and clinical activity of a single intravenous (IV) dose of BE-101 in adults with moderately severe or severe Hemophilia B. Once infused, BE-101 is designed to engraft and continuously secrete FIX into the circulation to restore clinically meaningful levels of active FIX. BE-101 is an autologous (person's own cells) B Cell Medicine (BCM) which uses CRISPR/Cas9 gene editing to precisely insert human FIX gene into those cells.

The study includes 2 distinct parts: Part 1 and Part 2. In Part 1, an ascending-dose design will be utilized to enable evaluation of increasing doses in a stepwise manner. The objective for this dose escalation is to identify the dose of BE-101 required to achieve desired FIX activity 28 days after infusion. Upon identification of a safe and efficacious dose in Part 1, an expansion phase (Part 2) will initiate. The initial cohort in the Part 2 expansion (Part 2a) phase will include up to 6 adult participants to further characterize the safety and activity of BE-101 at the selected dose. Additional cohorts for adolescents and redosing for participants in Part 1 of the study will occur following data availability of Part 1.

Up to 24 participants will be enrolled across Part 1 (up to 18) and Part 2a (up to 6). Consented participants will complete a screening period to assess eligibility and upon enrollment will undergo leukapheresis collection to support BE-101 manufacturing. Following administration, participants will be monitored for safety and clinical activity. The total duration of study participation is approximately 52 weeks post IV administration of BE-101.