NCT07187401RecruitingPhase 1/2
A First-in-Human Safety and Efficacy Study of ALN-CFB, a Small Interfering RNA (siRNA) Targeting Complement Factor B, in Adult Participants With Paroxysmal Nocturnal Hemoglobinuria With Persistent Anemia on a C5 Inhibitor
A Randomized, Double-Blind, Placebo-Controlled, First-In-Human Study of the Safety, Tolerability, Pharmacokinetics, and Preliminary Efficacy of ALN-CFB, an Investigational siRNA Therapeutic Against Complement Factor B, in Participants With Paroxysmal Nocturnal Hemoglobinuria and Persistent Anemia on Approved C5-Inhibitor Therapy
Source: ClinicalTrials.gov · Last updated 9 Jul 2026
Brief summary (registry, in English)
This study is researching an experimental drug called ALN-CFB. The study is focused on people with Paroxysmal Nocturnal Hemoglobinuria (PNH) who are currently taking a complement component C5 inhibitor ("C5-inhibitor") and continue to have anemia (low red blood cell count). The aim of the study is to see how tolerable ALN-CFB is compared to placebo. A placebo looks like the study drug but does not contain any drug. The study is looking at several other research questions, including: * What side effects may happen from taking ALN-CFB * How much ALN-CFB is in the blood at different times * How much Complement Factor B (CFB) protein levels in the blood are affected by ALN-CFB
- Status (registry)
- Recruiting
- Phase (registry)
- Phase 1/2
- Study type
- Interventional
- Enrollment
- 24 (estimated)
- First submitted
- 18 Sept 2025
- Start date
- 11 Feb 2026
- Primary completion date
- 29 Nov 2029
- Lead sponsor
- Regeneron Pharmaceuticals
- NCT number
- NCT07187401
- EU CT number
- 2024-519806-11-00
What you commit to
- Study type: Interventional · Phase 1/2
- Planned participants: 24
- From 11 Feb 2026 to the primary completion date, 29 Nov 2029
- 8 sites in 3 countries
- Visits and tests: ask the trial team, the registry does not list them
Built from the registry fields of ClinicalTrials.gov. It describes the study, not your situation.
Who cannot take part
Copied verbatim from ClinicalTrials.gov and grouped by topic. Only the trial team decides who can take part.
Prior treatment
- Has any active, ongoing infection or a recent infection requiring ongoing systemic treatment with antibiotics, antivirals, or antifungals within 2 weeks of screening or during the screening period
Other illness
- Has history of bone marrow transplantation or receipt of an organ transplant
- Has history of meningococcal infection or similar recurrent infections by other encapsulated bacterial organisms
- Have recent, unstable medical conditions, not related to PNH or PNH-related complications, as described in the protocol
- NOTE: Other Protocol Defined Inclusion / Exclusion Criteria Apply
Lab values
- Has laboratory evidence of bone marrow failure, as described in the protocol
Who the study is looking for
- Has been diagnosed with PNH confirmed by a history of high flow cytometry from prior testing
- Treated with a stable dose of C5 inhibitor (eculizumab or approved eculizumab biosimilar, ravulizumab, or crovalimab) for at least 24 weeks prior to screening visit, as described in the protocol
- Has hemoglobin ≤10.5 g/dL at screening visit 1, with evidence of anemia prior to this visit, as described in the protocol
- Has peripheral blood reticulocyte count of ≥100 x 10\^9/L at screening visit 1
Age in the registry: 18 years to - · Sex: All · Does not accept healthy volunteers
Sites (8)
Sites in registry order. Pick your city on the disease page to sort them by distance.
| Site | City | Country | Site status |
|---|---|---|---|
| Toronto General Hospital Coordinator of this site? Confirm its status | Toronto | Canada | Recruiting |
| St James's University Hospital Coordinator of this site? Confirm its status | Leeds | United Kingdom | Recruiting |
| Kings College Hospital NHS Foundation Trust Coordinator of this site? Confirm its status | London | United Kingdom | Recruiting |
| The Catholic University of Korea, Seoul ST. Mary's Hospital Coordinator of this site? Confirm its status | Seoul | South Korea | Recruiting |
| Severance hospital Coordinator of this site? Confirm its status | Seoul | South Korea | Recruiting |
| Seoul National University Hospital Coordinator of this site? Confirm its status | Seoul | South Korea | Recruiting |
| Samsung Medical Center Coordinator of this site? Confirm its status | Seoul | South Korea | Recruiting |
| St. Vincent Hospital - The Catholic University of Korea Coordinator of this site? Confirm its status | Suwon | South Korea | Recruiting |
This page is information, not medical advice. Discuss any trial with your doctor.