MedPath

A Study to Evaluate How Pozelimab + Cemdisiran Combination Therapy Works in Adult Patients With Paroxysmal Nocturnal Hemoglobinuria (PNH) Whose Current Treatment is Not Working Efficiently

Not Applicable
Not yet recruiting
Conditions
Paroxysmal Nocturnal Hemoglobinuria
Interventions
Registration Number
NCT07154745
Lead Sponsor
Regeneron Pharmaceuticals
Brief Summary

This study is researching a treatment combination with two experimental drugs called pozelimab and cemdisiran referred to as "study drugs". Researchers are looking for a better way to treat Paroxysmal Nocturnal Hemoglobinuria (PNH).

The aim of the study is to see how well the pozelimab and cemdisiran combination works to lower hemolysis in participants whose PNH has not gotten better even after taking other complement component 5 (C5) inhibitors, eculizumab/eculizumab biosimilar, ravulizumab or crovalimab.

The study is looking at several other research questions, including:

* What side effects may happen from taking the study drugs?

* How much of the study drugs are in the blood at different times?

* Whether the body makes antibodies against the study drug (which could make the study drugs not work as well or could lead to side effects)

Detailed Description

The treatment period has two parts, a Treatment Period (TP, 28 weeks) and an Extension treatment Period (EP, 52 weeks).

Recruitment & Eligibility

Status
NOT_YET_RECRUITING
Sex
All
Target Recruitment
35
Inclusion Criteria
  1. Diagnosis of PNH confirmed by a history of high-sensitivity flow cytometry from prior testing
  2. Currently treated with marketed eculizumab, ravulizumab, or crovalimab at the labeled dose for at least 6 months
  3. LDH persistently > 1.5 × Upper limit of normal (ULN) in the previous 6 months that the Principal Investigator (PI) attributes is due to intravascular hemolysis
  4. At least 2 screening LDH values from different visits as described in the protocol
  5. Willing and able to comply with clinic/remote visits and study-related procedures, including completion of the full series of meningococcal vaccinations required per protocol and agreement to continue to remain up to date with these vaccinations during the study

Key

Exclusion Criteria
  1. Receipt of an organ transplant, history of bone marrow transplantation or other hematologic transplants
  2. Body weight <40 kilograms at screening visit
  3. Patients with a known or suspected C5 mutation that is refractory to their current C5i treatment as described in the protocol
  4. Any active or ongoing infection within 2 weeks of screening or during the screening period or any recent infection as described in the protocol
  5. Known hereditary complement deficiency

Note: Other protocol-defined Inclusion/ Exclusion Criteria apply

Study & Design

Study Type
INTERVENTIONAL
Study Design
SINGLE_GROUP
Arm && Interventions
GroupInterventionDescription
Pozelimab + Cemdisiran ComboPozelimab-
Pozelimab + Cemdisiran ComboCemdisiran-
Primary Outcome Measures
NameTimeMethod
Percent change in Lactate Dehydrogenase (LDH) during TPFrom baseline to week 28
Secondary Outcome Measures
NameTimeMethod
Normalization of LDHThrough week 52
Change in fatigueThrough week 52

As measured by the Functional Assessment of Chronic Illness Therapy (FACIT)-Fatigue Scale.

The FACIT-Fatigue assesses the level of fatigue using a 5-point Likert scale ranging from 0 (not at all) to 4 (very much). Scores range from 0 to 52, with higher scores indicating a higher quality of life

Occurrence of all Adverse events (AEs)Through week 52
Adequate control of hemolysis (LDH ≤1.5 × ULN)Through week 52
Transfusion avoidanceThrough week 52

Not requiring a Red Blood Cell (RBC) transfusion as per protocol algorithm based on hemoglobin values

Change in hemoglobin from baselineThrough week 52
Concentrations of total C5Through week 52
Hemoglobin stabilizationThrough week 52

Patients who do not receive an RBC transfusion and have no decrease in hemoglobin level of ≥2 g/dL

Concentrations of total pozelimabThrough week 52
Concentrations of cemdisiranThrough week 52
Incidence of anti-drug antibody (ADA) to pozelimabThrough week 52
Titer of ADA to pozelimabThrough week 52
Incidence of ADA to cemdisiranThrough week 52
Titer of ADA to cemdisiranThrough week 52
Percent change in LDH during EPFrom baseline to week 24 and week 52
Severity of all AEsThrough week 52
Occurrence of all Treatment-Emergent Adverse Events (TEAEs)Through week 52
Severity of all TEAEsThrough week 52
Change from baseline in Total Complement Hemolytic Activity Assay (CH50)Through week 52

MedPath

Empowering clinical research with data-driven insights and AI-powered tools.

© 2025 MedPath, Inc. All rights reserved.