A Study to Test the Safety, Tolerability, and Efficacy of an Antibody, REGN7999, Injected Under the Skin for the Treatment of Iron Overload in Adult Participants with Non-Transfusion Dependent β-thalassemia, Using MRI Scans to Measure Iron Levels in the Body.

Overview

Sponsor-declared trial summary

Key facts

Sponsor

Regeneron Pharmaceuticals Inc.

Participant type

Patients

Age range

18-64 years

Gender

Male and Female

Therapeutic area

Diseases [C] - Musculoskeletal Diseases [C05]

Decision date (initial)

2025-04-15

Transition trial

No

Low-intervention

No

Rare-disease indication

Yes

Vulnerable population

No

External identifiers

EU CT number

2023-508604-37-00

ClinicalTrials.gov

NCT06421636

Trial design

CTIS Part I — objectives, methods, condition coding

Main objective

Scope: Pharmacokinetic, Safety, Pharmacodynamic, Efficacy, Others, Pharmacogenomic

To evaluate the effect of REGN7999 on LIC.
To evaluate the safety and tolerability of at least 2 different SC doses of REGN7999.

Secondary objectives 9

1. To evaluate the proportion of participants responding to REGN7999 with improvement in IOL.
2. To assess changes in hemoglobin concentration in response to REGN7999.
3. To evaluate the long-term effect of REGN7999 on LIC.
4. To evaluate further the effect of REGN7999 on LIC relative to baseline.
5. To assess further the changes in hemoglobin concentration in response to REGN7999.
6. To determine if REGN7999 impacts transfusion requirements.
7. To assess changes in RBC counts in response to REGN7999.
8. To characterize the pharmacokinetics of REGN7999.
9. To assess the immunogenicity of REGN7999.

Conditions and MedDRA coding

Non-transfusion dependent beta-thalassemia (NTDT), Beta-thalassemia Resultant Iron overload (IOL)

Eligibility criteria

Principal inclusion / exclusion criteria as submitted by sponsor

Inclusion criteria 4

1. Clinical diagnosis of NTDT as described in the protocol .
2. IOL, defined as LIC ≥ 5 mg Fe/g DW as measured by R2* MRI at screening.
3. Serum ferritin ≥ 300 ng/mL as described in the protocol.
4. Other protocol defined inclusion criteria apply.

Exclusion criteria 9

1. Hemoglobin ≤ 8 g/dL at screening.
2. Any RBC transfusion within 12 weeks of visit 3.
3. For Part A only: Any Iron Chelation Therapy (ICT) use in approximately 12 weeks prior to screening as described in the protocol.
4. For Part B only: If on ICT, any change in ICT dose in approximately 12 weeks prior to screening as described in the protocol.
5. Any use of luspatercept or mitapivat in 6 months prior to screening as described in the protocol.
6. Absolute contraindication to MRI.
7. Diagnosis of cirrhosis of the liver.
8. Diagnosis of Chronic kidney disease (CKD) stage 4 or higher.
9. Other protocol defined exclusion criteria apply.

Endpoints

Primary and secondary outcome measures (English text)

Primary endpoints 3

1. Change from baseline in Liver iron concentration (LIC) by R2* magnetic resonance imaging (MRI).
2. Incidence of Treatment-emergent adverse events (TEAEs).
3. Severity of Treatment-emergent adverse events (TEAEs).

Secondary endpoints 13

1. Achievement of ≥20% reduction in LIC by R2* MRI.
2. Change from baseline in hemoglobin.
3. Change from baseline in LIC by R2* MRI.
4. Percent change from baseline in LIC by R2* MRI.
5. Achievement of ≥20% reduction from baseline LIC by R2*.
6. Change in hemoglobin over time.
7. Achievement of ≥1.5 g/dL increase in hemoglobin for two consecutive assessments in the absence of red blood cell (RBC) transfusions.
8. Number of RBC transfusions required.
9. Achievement of transfusion independence.
10. Change in RBC counts over time.
11. Concentrations of REGN7999 in serum over time.
12. Incidence of anti-drug antibody (ADA) to REGN7999 over time.
13. Magnitude of ADA to REGN7999 over time.

Investigational products

Investigational medicinal products (IMPs), comparators, placebo, auxiliary

Test 1

Placebo 1

Sponsors and contacts

Sponsor organisations, regulatory contacts, third parties

Regeneron Pharmaceuticals Inc.

Sponsor organisation

Regeneron Pharmaceuticals Inc.

Address

777 Old Saw Mill River Road

City

Tarrytown

Postcode

10591-6717

Country

United States

Scientific contact point

Organisation

Regeneron Pharmaceuticals Inc.

Contact name

Medical Affairs

Public contact point

Organisation

Regeneron Pharmaceuticals Inc.

Contact name

Medical Affairs

Third parties 7

Locations

2 EU/EEA countries · 7 investigational sites

By country

Investigational sites

Results and documents

Annex IV summary of results, Annex V layperson summary, and all documents registered in CTIS for this trial

Documents 23 files

Public protocol annexes, IB summaries, regulatory submissions and post-authorisation documents registered in CTIS.

Application history

4 submissions — initial application plus substantial / non-substantial modifications