Phase 1 study to evaluate safety, tolerability, PK and PD of single ascending dose of REGN7508

  • Research type

    Research Study

  • Full title

    A PHASE 1, RANDOMIZED, DOUBLE-BLIND, PLACEBO-CONTROLLED, SINGLE-CENTER STUDY TO EVALUATE THE SAFETY, TOLERABILITY, PHARMACOKINETICS, ANDPHARMACODYNAMICS OF SINGLE ASCENDING DOSES OF REGN7508, A MONOCLONAL ANTIBODY AGAINST FACTOR XI, IN HEALTHY ADULT SUBJECTS

  • IRAS ID

    1006431

  • Contact name

    Muriel O'Byrne

  • Contact email

    muriel.obyrne@regeneron.com

  • Sponsor organisation

    Regeneron Pharmaceuticals, Inc.

  • Eudract number

    2022-002001-20

  • Clinicaltrials.gov Identifier

    NCT05603195

  • Research summary

    This is a phase 1, randomized, double-blind, placebo-controlled, single-site first-in-human (FIH) study of REGN7508. The objective of this study is to evaluate the safety, tolerability, drug levels in the body and drug effects of REGN7508, a monoclonal (synthetic) antibody (mAb) that binds FXI/FXIa and prevents activation of Factor IX (FIX) by Factor XIa (FXIa), in healthy adults. This study uses a single ascending dose design. Participants are randomized in a 3:1 ratio of REGN7508:placebo in up to 9 dose cohorts: 5 intravenous (IV) dose administration, 2 subcutaneous (SC) dose administration, and 2 optional cohorts.

    The first two participants in each cohort (sentinel participants) are dosed at least 48 hours prior to the remaining participants in the cohort and are randomized in a 1:1 manner (REGN7508:placebo). Maximal drug effects with IV doses are expected within 48 hours based on results of pre-clinical studies. The remaining participants in the cohort are dosed only after both sentinel participants in the cohort have completed at least 48 hours of safety assessments and the data have been reviewed by the investigator and Sponsor with the decision documented by the investigator and the Sponsor. Subcutaneously dosed cohorts may be initiated once all participants enrolled in an equivalent or higher IV dosed cohort have been observed for at least 7 days post-study drug administration and have completed day 8 (visit 6) safety assessments and after the data have been reviewed at a Dose Escalation Review meeting.

    The minimum study duration for each participant is approximately 36 days of clinic visits, including the 3 day Inpatient Treatment Period and 33 day Outpatient clinic Follow-Up Period. The length of the outpatient clinic follow up period may be extended to accommodate prolonged drug effects. Participant who complete the clinic visits before day 100 will have a day 100 telephone call to ensure compliance with contraception rules.

  • REC name

    London - London Bridge Research Ethics Committee

  • REC reference

    22/LO/0789

  • Date of REC Opinion

    29 Nov 2022

  • REC opinion

    Further Information Favourable Opinion