A Long-Term Follow-Up Study of Haemophilia B Patients Who Have Undergone Gene Therapy

An Open-Label, Multicentre, Long-Term Follow-Up Study to Investigate the Safety and Durability of Response Following Dosing of a Novel Adeno-Associated Viral Vector (FLT180a) in Patients with Haemophilia B

Status

Not yet recruiting

Phases

Phase 2Phase 3

Study type

Interventional

Source

EU CTR

Registry ID

EUCTR2017-005080-40-GB

Enrollment

Registered

2018-02-19

Start date

2018-05-15

Completion date

Unknown

Last updated

2020-05-04

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Haemophilia B MedDRA version: 20.0 Level: LLT Classification code 10018939 Term: Haemophilia B (Factor IX) System Organ Class: 100000004850

Interventions

Product Name: FLT180a Product Code: FLT180a Pharmaceutical Form: Concentrate for solution for infusion INN or Proposed INN: N/A CAS Number: N/A Current Sponsor code: FLT180A Other descriptive name: FL

Eligibility

Sex/Gender

Male

Inclusion criteria

Inclusion criteria: 1. Patients who have previously received FLT180a within a clinical study. 2. Able to give full informed consent and able to comply with all requirements of the study including long-term follow-up for the timeframe the study requires. 3. Willing to practice barrier contraception until at least 3 consecutive semen samples after vector administration are negative for vector sequence*. *only applicable if vector genome shedding in semen sample persists at end of study in the preceding clinical study where FLT180a is administered. Are the trial subjects under 18? no Number of subjects for this age range: F.1.2 Adults (18-64 years) yes F.1.2.1 Number of subjects for this age range 35 F.1.3 Elderly (>=65 years) yes F.1.3.1 Number of subjects for this age range 15

Exclusion criteria

Exclusion criteria: None, if both inclusion criteria are met

Design outcomes

Primary

Measure	Time frame
Main Objective: Safety -To assess the long-term safety following systemic administration of FLT180a in patients with haemophilia B. -To investigate the durability of endogenous Factor IX (FIX) activity following systemic administration of FLT180a.;Secondary Objective: To investigate the long-term effectiveness of FLT180a on annualized bleeding rate and exogenous FIX consumption. To investigate the effectiveness of FLT180a related to surgical or dental procedures. To describe the immune responses to the human FIX (hFIX) transgene product following systematic administration of FLT180a. To assess viral shedding in various body fluids after systematic administration of FLT180a.;Primary end point(s): Primary Safety Endpoint • Safety as assessed by the reporting of adverse events (AEs)/adverse reactions (ARs) according to Common Terminology Criteria for Adverse Events (CTCAE) version 5.0 or later. Primary Efficacy Endpoint • The durability of response will be estimated from the rate of decline of the FIX activity observed.;Timepoint(s) of evaluation of this end point: Primary Safety Endpoint at Day 1, at Month 3,6,12,18, than Annually until EoS Primary Efficacy Endpoint at Day 1, at Month 3,6,12,18, than Annually at Year 2,3,4,5	—

Measure

Time frame

Main Objective: Safety -To assess the long-term safety following systemic administration of FLT180a in patients with haemophilia B. -To investigate the durability of endogenous Factor IX (FIX) activity following systemic administration of FLT180a.;Secondary Objective: To investigate the long-term effectiveness of FLT180a on annualized bleeding rate and exogenous FIX consumption. To investigate the effectiveness of FLT180a related to surgical or dental procedures. To describe the immune responses to the human FIX (hFIX) transgene product following systematic administration of FLT180a. To assess viral shedding in various body fluids after systematic administration of FLT180a.;Primary end point(s): Primary Safety Endpoint • Safety as assessed by the reporting of adverse events (AEs)/adverse reactions (ARs) according to Common Terminology Criteria for Adverse Events (CTCAE) version 5.0 or later. Primary Efficacy Endpoint • The durability of response will be estimated from the rate of decline of the FIX activity observed.;Timepoint(s) of evaluation of this end point: Primary Safety Endpoint at Day 1, at Month 3,6,12,18, than Annually until EoS Primary Efficacy Endpoint at Day 1, at Month 3,6,12,18, than Annually at Year 2,3,4,5

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Secondary

Measure	Time frame
Secondary end point(s): Endogenous hFIX Production Haemostatic Effectiveness Immune Response Safety Shedding;Timepoint(s) of evaluation of this end point: Endogenous hFIX Production: at Day 1, at Month 3,6,12,18, than Annually at Year 2,3,4,5 Haemostatic Effectiveness: at Day 1, at Month 3,6,12,18, than Annually at Year 2,3,4,5 Immune Response: at Day 1, at Month 3,6,12,18, than Annually at Year 2,3,4,5	—

Measure

Time frame

Secondary end point(s): Endogenous hFIX Production Haemostatic Effectiveness Immune Response Safety Shedding;Timepoint(s) of evaluation of this end point: Endogenous hFIX Production: at Day 1, at Month 3,6,12,18, than Annually at Year 2,3,4,5 Haemostatic Effectiveness: at Day 1, at Month 3,6,12,18, than Annually at Year 2,3,4,5 Immune Response: at Day 1, at Month 3,6,12,18, than Annually at Year 2,3,4,5

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Countries

Germany, Ireland, Italy, South Africa, Sweden, United Kingdom, United States

Contacts

Public ContactClinical Operations

Freeline Therapeutics Limited

contact@freeline.life

Outcome results

None listed

Source: EU CTR (via WHO ICTRP) · Data processed: Feb 4, 2026