CClinicalTrials.gg
Sign In
RecruitingNCT07444294Updated Mar 2, 2026

A Single- and Multiple-Ascending Dose Study of SRK-439 in Healthy Adults

A Phase 1 interventional study of Placebo and SRK-439 in Healthy, sponsored by Scholar Rock, Inc.. Recruiting at 1 site in United States. Open to participants aged 18 Years to 55 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-03-02.

Sponsored by Scholar Rock, Inc. · Phase 1, Interventional, and Treatment

Phase
Phase 1
Study type
Interventional
Enrollment
76
Allocation
Randomized
Ages
18 Years to 55 Years
Sex
All
01

Study summary

A phase 1 study to assess the safety, tolerability, pharmacokinetics, and pharmacodynamics of SRK-439 in healthy adults

02

Conditions studied

  • Healthy
03

Who can participate

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

Eligibility criteria

Key Inclusion Criteria:

  1. Male or female participants, ≥18 to ≤55 years of age, at the time of informed consent
  2. BMI of ≥18 kg/m2 to ≤35 kg/m2 (inclusive) at screening

Exclusion Criteria:

  1. Previous treatment with SRK-439 or apitegromab, or with other anti-myostatin therapies, including ACTR antagonists.
  2. History of immunosuppressive, chemotherapeutic, or radiation treatment within 12 months prior to screening.
  3. Current or prior use of anabolic steroids, growth hormones, or other substances with known effects on muscle.
  4. Use of therapies with potentially significant muscle effects (eg, insulin-like growth factor, systemic beta-agonist, neurotoxins, or muscle relaxants or muscle-enhancing supplements) in any form within 3 months prior to screening or during the study.
  5. Any history of exposure to a mAb or Fc domain-bearing recombinant protein within 5 years prior to screening with any prior history of hypersensitivity reactions from exposure
  6. Treatment with other investigational drugs or devices in a clinical study or exposure to a biologic therapeutic within 3 months or 5 half-lives, whichever is longer, prior to screening.
04

Study design

Phase
Phase 1
Primary purpose
Treatment
Allocation
Randomized
Intervention model
Sequential assignment
Masking
Quadruple (Participant, Care provider, Investigator, Outcomes assessor)
Enrollment
76 participants (estimated)

Study arms

  • Experimental
    Part A

    Participants will be treated with a single dose of SRK-439 or matching placebo.

    Drug: Placebo · Drug: SRK-439

  • Experimental
    Part B

    Participants will be treated with multiple doses of SRK-439 or matching placebo.

    Drug: Placebo · Drug: SRK-439

Interventions

  • DrugPlacebo

    Matching placebo to SRK-439, subcutaneous administration

  • DrugSRK-439

    Single ascending dose, subcutaneous administration

  • DrugSRK-439

    Multiple ascending dose, subcutaneous administration

05

What researchers measure

Primary outcomes

  1. Evaluate the safety and tolerability of single and multiple SRK-439 SC dose administration in healthy adult participants

    • Incidence of AEs

    Time frame: Up to 32 weeks

  2. Evaluate the safety and tolerability of single and multiple SRK-439 SC dose administration in healthy adult participants

    • Incidence of SAEs

    Time frame: Up to 32 weeks

  3. Evaluate the safety and tolerability of single and multiple SRK-439 SC dose administration in healthy adult participants

    Changes from baseline in clinical safety laboratory tests (serum chemistry)

    Time frame: Up to 32 weeks

  4. Evaluate the safety and tolerability of single and multiple SRK-439 SC dose administration in healthy adult participants

    Changes from baseline in clinical safety laboratory tests (hematology)

    Time frame: Up to 32 weeks

  5. Evaluate the safety and tolerability of single and multiple SRK-439 SC dose administration in healthy adult participants

    Changes from baseline in clinical safety laboratory tests (urinalysis)

    Time frame: Up to 32 weeks

  6. Evaluate the safety and tolerability of single and multiple SRK-439 SC dose administration in healthy adult participants

    Changes from baseline in clinical safety laboratory tests (coagulation assessments)

    Time frame: Up to 32 weeks

  7. Evaluate the safety and tolerability of single and multiple SRK-439 SC dose administration in healthy adult participants

    Changes from baseline in vital signs (heart rate) measured in bpm

    Time frame: Up to 32 weeks

  8. Evaluate the safety and tolerability of single and multiple SRK-439 SC dose administration in healthy adult participants

    Changes from baseline in vital signs (blood pressure) measured in mmHg

    Time frame: Up to 32 weeks

  9. Evaluate the safety and tolerability of single and multiple SRK-439 SC dose administration in healthy adult participants

    Changes from baseline in vital signs (respiratory rate) measured in rpm

    Time frame: Up to 32 weeks

  10. Evaluate the safety and tolerability of single and multiple SRK-439 SC dose administration in healthy adult participants

    Changes from baseline in vital signs (body temperature) measured in Celsius

    Time frame: Up to 32 weeks

  11. Evaluate the safety and tolerability of single and multiple SRK-439 SC dose administration in healthy adult participants

    Changes from baseline in ECG measurements

    Time frame: Up to 32 weeks

Secondary outcomes

  1. Evaluate the PK of single and multiple SRK-439 SC dose administration in healthy adult participants

    • Maximum observed serum concentration \[Cmax\]

    Time frame: Up to 32 weeks

  2. Evaluate the PK of single and multiple SRK-439 SC dose administration in healthy adult participants

    • Time to maximum observed concentration in serum \[Tmax\]

    Time frame: Up to 32 weeks

  3. Evaluate the PK of single and multiple SRK-439 SC dose administration in healthy adult participants

    • Area under the serum concentration-time curve \[AUC\]

    Time frame: Up to 32 weeks

  4. Evaluate the PK of single and multiple SRK-439 SC dose administration in healthy adult participants

    • Terminal elimination half-life in serum \[t1/2\]

    Time frame: Up to 32 weeks

  5. Evaluate the PD of single and multiple SRK-439 SC dose administration in healthy adult participants

    Serum concentrations of total latent myostatin and changes over time

    Time frame: Up to 32 weeks

  6. Evaluate the immunogenicity of single and multiple SRK-439 SC dose administration in healthy adult participants

    Incidence of ADAs against SRK-439 in serum

    Time frame: Up to 32 weeks

06

Study locations

1 of 1 sites recruiting
  • Medpace CPU
    Cincinnati, Ohio 45227, United States
    Recruiting
07

Registry details

Key details

Study ID
NCT07444294
Lead sponsor
Scholar Rock, Inc.
Responsible party
Sponsor
First posted
Mar 2, 2026
Start date
Nov 21, 2025
Primary completion
Dec 17, 2026 (estimated)
Completion
Jun 9, 2027 (estimated)
Last update
Mar 2, 2026

Study contacts

Scholar Rock, Inc. Clinical Trials Administration
Contact
MedicalInformation@scholarrock.com
857-259-3860

Oversight

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

Interested in this study?

Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.

Contact study team

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.

Other studies from this sponsor

Scholar Rock, Inc.

Start the discussion