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NCT03188666 · ClinicalTrials.gov registry record · Phase 2
A Study to Examine the Safety, Tolerability and Effects on Abnormal Bone Formation of REGN2477 in Patients With Fibrodysplasia Ossificans Progressiva
A Phase 2 study, sponsored by Regeneron Pharmaceuticals.
- Completed
- Registry status
- Phase 2
- Development phase
- 44
- Enrollment target
NCT03188666: Completed Phase 2 study, sponsored by Regeneron Pharmaceuticals.
NCT03188666 is a Phase 2 study that has completed, run by Regeneron Pharmaceuticals. The registered enrollment target is 44 participants, below the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (67% lower). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT03188666, a Phase 2 study, has completed, sponsored by Regeneron Pharmaceuticals.
- COMPLETED
- Registry status
- Phase 2
- Development phase
- 44 participants
- Enrollment target
Study Summary
This is a three period study design consisting of a 6-month, randomized, double-blind placebo-controlled treatment (period 1) followed by a 6-month, open-label treatment (period 2) and a follow-up treatment period (period 3). Primary safety objective of the study is to assess the safety and tolerability of REGN2477 in male and female patients with fibrodysplasia ossificans progressiva (FOP). Primary efficacy objective of the study is to assess the effect of REGN2477 versus placebo on the change from baseline in heterotopic ossification (HO) in patients with FOP, as determined by 18-NaF uptake in HO lesions by positron emission tomography (PET) and in total volume of HO lesions by computed tomography (CT). Key Secondary objectives are: * To compare the effect of REGN2477 versus placebo on pain due to FOP, as measured by the area under the curve (AUC) for pain based on daily pain numeric rating scale (NRS) scores * To assess the effect of REGN2477 versus placebo on the change from baseline in HO, as determined by the number of new HO lesions identified by 18F-NaF PET or by CT * To assess the effect of REGN2477 versus placebo on the change from baseline in 18F-NaF standardized uptake value maximum (SUVmax) of individual active HO site(s) by PET * To assess the effect of REGN2477, between week 28 and week 56, on the number, activity, and volume of HO lesions identified by 18F-NaF PET or by CT in patients who switch from placebo to REGN2477 at week 28 versus the same patients between baseline and week 28 * To assess the effect of REGN2477 versus placebo on the change from baseline in biochemical markers of bone formation * To characterize the concentrations of total activin A at baseline and over time following the first dose of study drug * To characterize the concentration-time profile (pharmacokinetics \[PK\]) of REGN2477 in patients with FOP * To assess the immunogenicity of REGN2477
Primary Outcome
Treatment-emergent adverse events (TEAEs) are adverse events not present at baseline or represent the exacerbation of a pre-existing condition during the on-treatment period. A serious TEAE was defined as any untoward medical occurrence that resulted in any of following outcomes not present at baseline or represent the exacerbation of a pre-existing condition during the on-treatment period: death, life-threatening, required initial/prolonged in-participant hospitalization, persistent/significant
Interventions
- DRUG Matching placebo
- DRUG REGN2477
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 44 participants |
| Start Date | 2018-02-26 |
| Est. Completion | 2021-09-16 |
| Phase | Phase 2 |
What the finished NCT03188666 record still lists
NCT03188666 is an interventional study that assigns participants to a tested intervention. The registry caps enrollment at 44 participants, a relatively small participant target, below the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (67% lower).
The record links to 0 conditions, and to 2 interventions - of which Matching placebo is the first listed.
NCT03188666 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT03188666 about?
NCT03188666 is a clinical study titled "A Study to Examine the Safety, Tolerability and Effects on Abnormal Bone Formation of REGN2477 in Patients With Fibrodysplasia Ossificans Progressiva". This is a three period study design consisting of a 6-month, randomized, double-blind placebo-controlled treatment (period 1) followed by a 6-month, open-label treatment (period 2) and a follow-up treatment period (period 3). Primary safety objective of the study is to assess the safety and tolerab...
What is the current status of trial NCT03188666?
This trial is currently completed. It is a Phase 2 study. The enrollment target is 44 participants. The study started on 2018-02-26. Estimated completion is 2021-09-16.
What interventions are being tested in trial NCT03188666?
The interventions under investigation include: Matching placebo (DRUG), REGN2477 (DRUG).
Who is sponsoring clinical trial NCT03188666?
This trial is sponsored by Regeneron Pharmaceuticals, which has 280 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT03188666's enrollment target sits among peer trials
44 1322nd of 2000 higher than 669 of 2,000 other Phase 2 trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other Phase 2 trials. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source ClinicalTrials.gov registry export · 2026-08-08
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