Actively Recruiting
A Two-Part Open-Label Study of REGV131-LNP1265, a CRISPR/Cas9-Based Coagulation Factor IX Gene Insertion Therapy in Participants With Hemophilia B
Led by Regeneron Pharmaceuticals · Updated on 2026-05-19
130
Participants Needed
42
Research Sites
678 weeks
Total Duration
On this page
Sponsors
R
Regeneron Pharmaceuticals
Lead Sponsor
I
Intellia Therapeutics
Collaborating Sponsor
AI-Summary
What this Trial Is About
This research aims to evaluate an experimental gene insertion therapy called REGV131-LNP1265 in male participants with severe or moderately severe hemophilia B caused by a genetic mutation in the Factor 9 gene. The therapy seeks to help the body produce clotting factor long-term without the need for regular factor replacement. The main goal is to find a safe and well-tolerated dose by monitoring side effects over time and studying how the body responds to the therapy. The study has two parts: Part 1 involves dose escalation and confirmation in adult males aged 18 years and older to determine the recommended dose for expansion (RDE). Part 2 includes dose expansion cohorts where adults, adolescents aged 12 to under 18, and pediatric participants aged 2 to under 12 receive weight-adjusted doses based on the RDE. Participants receive the study drugs REGV131 and LNP1265 according to the protocol, with dosing adjusted by age group and weight. Participants will be monitored for side effects, clotting factor activity in the blood, antibody responses to the therapy and clotting factor, and bleeding rates. Various biological samples, including blood, saliva, urine, and semen, will be tested for the presence of the therapy components and antibodies. Safety and effectiveness outcomes will be tracked for up to 15 years to assess long-term effects. The study involves regular assessments of bleeding rates and clotting factor levels to evaluate the therapy's impact.
CONDITIONS
Brief Title
A Study to Investigate the Safety and Effectiveness of a Coagulation Factor IX Gene Insertion Therapy (REGV131-LNP1265) in Pediatric, Adolescent and Adult Participants With Hemophilia B
Who Can Participate
Eligibility Criteria
You may qualify if you...
- Confirmed diagnosis of severe or moderately severe hemophilia B with FIX functional activity ≤2% or documented genotype producing severe hemophilia B
- Currently receiving FIX prophylaxis and have previous experience with FIX therapy
- Participation in the lead-in period of this study or a separate lead-in study for at least 6 months for bleeding rate data while on FIX prophylaxis
- Male participants aged 2 years or older
You will not qualify if you...
- History of FIX inhibitor on two or more occasions
- Bethesda inhibitor titer above the upper limit of normal at screening
- Detectable pre-existing antibodies to the AAV8 capsid at prescreening
- Significant underlying liver diseases such as cholestatic liver disease, cirrhosis, portal hypertension, splenomegaly, or hepatic encephalopathy
- Evidence of advanced liver fibrosis or significant fatty liver
- Evidence of cirrhosis or portal hypertension assessed within 6 months prior to screening
- History of arterial or venous thrombo-embolic events
- History of hypersensitivity to corticosteroids or conditions requiring chronic corticosteroid use
- Previous receipt of any AAV gene-based therapy other than REGV131-LNP1265 or planned receipt during the study period
AI-Screening
AI-Powered Screening
Complete this quick 3-step screening to check your eligibility
Your Study Journey
Duration - 2 to 4 weeks
Participants are screened for eligibility to participate in the trial.
1 visit (in-person)
Duration - Up to 2 years
Participants receive the REGV131-LNP1265 gene insertion therapy at the recommended dose for expansion (RDE) or weight-adjusted RDE depending on age group.
Initial dosing visit followed by regular visits to monitor safety and effectiveness
Duration - Up to 15 years
Participants are followed for up to 15 years to monitor long-term safety and lasting effects of the gene therapy.
Periodic visits over the long-term follow-up period
Trial Site Locations
Total: 42 locations
1
Orthopaedic Hemophilia Treatment Center
Los Angeles, California, United States, 90007
Actively Recruiting
2
David Geffen School of Medicine at UCLA
Los Angeles, California, United States, 90024
Actively Recruiting
3
Children's Hospital Los Angeles
Los Angeles, California, United States, 90027
Actively Recruiting
4
University of California Davis
Sacramento, California, United States, 95817
Actively Recruiting
5
University California San Francisco
San Francisco, California, United States, 94143
Actively Recruiting
6
University of Colorado Hemophilia and Thrombosis Center
Aurora, Colorado, United States, 80045
Actively Recruiting
7
Yale HTC
New Haven, Connecticut, United States, 06510
Actively Recruiting
8
University of Florida
Gainesville, Florida, United States, 32610
Actively Recruiting
9
Indiana Hemophilia and Thrombosis Center
Indianapolis, Indiana, United States, 46260
Actively Recruiting
10
Tulane University School of Medicine, Louisiana Center for Bleeding and Clotting Disorders
New Orleans, Louisiana, United States, 70112
Actively Recruiting
11
University of Michigan
Ann Arbor, Michigan, United States, 48109
Actively Recruiting
12
Nationwide Children's Hospital
Columbus, Ohio, United States, 43205
Actively Recruiting
13
Children's Hospital of Philadelphia (CHOP)
Philadelphia, Pennsylvania, United States, 19104
Actively Recruiting
14
Vanderbilt University Medical Center
Nashville, Tennessee, United States, 37232
Actively Recruiting
15
Royal Prince Alfred Hospital, Haemophilia Treatment Centre
Camperdown, New South Wales, Australia, 2050
Actively Recruiting
16
University of Alberta Hospital
Edmonton, Alberta, Canada, T6G 2B7
Actively Recruiting
17
McMaster University Medical Centre - Hamilton Health Sciences
Hamilton, Ontario, Canada, L8N 3Z5
Actively Recruiting
18
McGill University Health Center (MUHC)
Montreal, Quebec, Canada, H4J 3A1
Actively Recruiting
19
Hospices Civils de Lyon
Bron, Lyon, France, 69677
Actively Recruiting
20
Hemostase Clinique, Institut Coeur Poumon
Lille, Nord, France, 59037
Actively Recruiting
21
Hopital Necker
Paris, Île-de-France Region, France, 75015
Actively Recruiting
22
University Hospital Frankfurt
Frankfurt am Main, Hesse, Germany, 60590
Actively Recruiting
23
University Hospital Hamburg Eppendorf
Hamburg, Germany, 20246
Actively Recruiting
24
Careggi University Hospital
Florence, Firenze, Italy, 50134
Actively Recruiting
25
Fondazione Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Ca Granda Ospedale Maggiore Policlinico
Milan, Lombardy, Italy, 20122
Actively Recruiting
26
Irccs Humanitas Research Hospital
Rozzano, Lombardy, Italy, 20089
Actively Recruiting
27
Ospedale san Bortolo
Vicenza, Italy, 36100
Actively Recruiting
28
Hospital Universitario Virgen del Rocio
Seville, Andalusia, Spain, 41013
Actively Recruiting
29
Complejo Hospitalario Universitario de A Coruña (Edificio Teresa Herrera-Materno Infantil)
A Coruña, Galicia, Spain, 15006
Actively Recruiting
30
Hospital Clinico Universitario Virgen De La Arrixaca
El Palmar, Murcia, Spain, 30120
Actively Recruiting
31
Hospital Universitario Central de Asturias
Oviedo, Principality of Asturias, Spain, 33011
Actively Recruiting
32
Hospital Universitario Vall d'Hebron
Barcelona, Spain, 08035
Actively Recruiting
33
Hospital Universitario La Paz
Madrid, Spain, 28046
Actively Recruiting
34
Haemostasis and Thrombosis Unit, Hospital La Fe
Valencia, Spain, 46026
Actively Recruiting
35
Hospital Universitario Miguel Servet
Zaragoza, Spain, 50009
Actively Recruiting
36
Glasgow Royal Infirmary - Clinical Research Facility
Glasgow, Scotland, United Kingdom, G31 2ER
Actively Recruiting
37
Queen Elizabeth Hospital Birmingham
Birmingham, West Midlands, United Kingdom, B15 2TH
Actively Recruiting
38
Addenbrooke's Hospital, Cambridge University Hospitals NHS FT
Cambridge, United Kingdom, CB2 0QQ
Actively Recruiting
39
Pathology and Pharmacy Building, The Royal London Hospital
London, United Kingdom, E1 2ES
Actively Recruiting
40
Royal Free London NHS Foundation Trust
London, United Kingdom, NW3 2QG
Actively Recruiting
41
St. Thomas' Hospital
London, United Kingdom, SE1 7EH
Actively Recruiting
42
Hammersmith Hospital Comprehensive Care Centre
London, United Kingdom, W12 0HS
Actively Recruiting
Research Team
C
Clinical Trials Administrator
How is the study designed?
Study Type
INTERVENTIONAL
Masking
NONE
Allocation
NON_RANDOMIZED
Model
SEQUENTIAL
Primary Purpose
TREATMENT
Number of Arms
7
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