CClinicalTrials.gg
CompletedNCT06669234Updated Sep 30, 2026

Phase 1 Safety and Tolerability Study of ALN-F1202 in Healthy Adults

A Phase 1 interventional study of ALN-F1202 and Matching Placebo in Healthy Volunteer, sponsored by Regeneron Pharmaceuticals. Completed at 1 site in Belgium. Open to participants aged 18 Years to 55 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-09-30.

Sponsored by Regeneron Pharmaceuticals · Phase 1, Interventional, and Treatment

Updated Sep 30, 2026Now CompletedStudy completion movedGo to Updates ↓
Phase
Phase 1
Study type
Interventional
Enrollment
56
Allocation
Randomized
Ages
18 Years to 55 Years
Sex
All
01

Study summary

This clinical research trial will evaluate the safety and tolerability of an experimental drug, ALN-F1202, in healthy participants.

The purpose of this trial is to learn about how safe and tolerable the experimental drug is. The trial is looking at several other research questions, including:

  • What side effects may happen from taking the experimental drug?
  • How much experimental drug is in the blood at different times?
  • Whether the body makes antibodies against the experimental drug (which could make the drug less effective or could lead to side effects).
  • What is the best dose of the experimental drug?
02

Conditions studied

  • Healthy Volunteer
03

In context

Lead sponsor

Regeneron Pharmaceuticals is the lead sponsor of 400 studies on the registry; 91 are open to participants now.

Of its 120 completed or terminated interventional studies of FDA-regulated products, 77 (64%) have results posted.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years to 55 Years
Sexes eligible
All
Accepts healthy volunteers
Yes

Eligibility criteria

Key Inclusion Criteria:

  1. Has a body mass index between 18 and 32 kg/m2, inclusive
  2. Is judged by the investigator to be in good health based on medical history, physical examination, vital sign measurements, and electrocardiograms (ECGs) performed at screening and/or prior to administration of initial dose of study drug
  3. Is in good health based on laboratory safety testing obtained at the screening visit, as described in the protocol
  4. Normal aPTT, normal PT, and normal platelet counts at screening period and at day -1 as defined by the local laboratory
  5. Hemoglobin values at screening period and at day -1 as described in the protocol

Key Exclusion Criteria:

  1. History of any major surgical procedure or clinically significant physical trauma, in the opinion of the investigator, that may pose a risk to the participant by study participation
  2. Whole blood donation within the previous 56 days or plasma donation within the previous 7 days prior to screening
  3. History of clinically significant bleeding, requiring hospitalization or blood products, that in the opinion of the investigator may pose a risk to the participant by study participation
  4. History of bleeding diathesis as described in the protocol
  5. Members of the clinical site study team and/or his/her immediate family, unless prior approval granted by the sponsor
  6. Presents any concern to the study investigator that might confound the results of the study or poses an additional risk to the participant by their participation in the study

NOTE: Other protocol-defined inclusion/exclusion criteria apply

05

Study design

Phase
Phase 1
Primary purpose
Treatment
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Quadruple (Participant, Care provider, Investigator, Outcomes assessor)
Enrollment
56 participants (actual)

Study arms

  • Experimental
    ALN-F1202

    Randomized as described in the protocol Escalating Cohorts including Optional Cohorts

    Drug: ALN-F1202

  • Experimental
    Placebo

    Randomized as described in the protocol

    Drug: Matching Placebo

Interventions

  • DrugALN-F1202

    Administered per the protocol

  • DrugMatching Placebo

    Administered per the protocol

06

What researchers measure

Primary outcomes

  1. Incidence of Treatment Emergent Adverse Events (TEAEs)

    Time frame: Up to 190 Days

  2. Severity of TEAEs

    Time frame: Up to 190 Days

Secondary outcomes

  1. Change in activated Partial Thromboplastin Time (aPTT)

    Time frame: Baseline up to 190 Days

  2. Change in Prothrombin Time (PT)

    Time frame: Baseline up to 190 Days

  3. Concentration of combined ALN-F1202 and metabolites in plasma

    Time frame: Up to 190 Days

  4. Extent of urinary excretion of combined ALN-F1202 and metabolites

    Time frame: Within 24 hours of treatment

07

Study locations

1 site
  • Center for Clinical Pharmacology University Hospitals Leuven (UZ Leuven)
    Leuven, Vlaams-Brabant 3000, Belgium
08

References and documents

Individual participant data

Plan to share: Yes — All Individual Patient Data (IPD) that underlie publicly available results will be considered for sharing.

Supporting information: Study protocol, Sap, Icf, Csr, Analytic code

No publications or documents are linked to this record.

09

Updates

1 registry update since Sep 25, 2026
Status
Active, not recruiting→Completed
changed Sep 30, 2026
Study completion
Jul 30, 2026→Aug 4, 2026 (actual)
Sep 30, 2026
Show all 1 update
  1. Sep 30, 2026
    Active, not recruiting→Completed
    Study completion Jul 30, 2026→Aug 4, 2026 (now actual)
    + 1 other change: verification date

From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗

10

Registry details

Key details

Study ID
NCT06669234
Lead sponsor
Regeneron Pharmaceuticals
Responsible party
Sponsor
First posted
Nov 1, 2024
Start date
Mar 6, 2025
Primary completion
Jul 30, 2026
Completion
Aug 4, 2026
Last update
Sep 30, 2026

Study contacts

Clinical Trial Management
study director · Regeneron Pharmaceuticals

Oversight

Data monitoring committee
No
FDA-regulated drug
Yes
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is completed, as verified in Sep 2026. You cannot join it, but the record below documents what was studied.

Follow this study

Get an email when the registry record changes — status, dates, results — or when someone posts here.

Sign in to follow

Discussion

Questions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.

Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.

Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.

Start the discussion