Overweight and ObesityPhase 2EMBRAZENCT06445075
Efficacy and Safety of Apitegromab for the Treatment of Adults Who Are Overweight or Obese
A Phase 2 study testing Apitegromab and Tirzepatide in people with Overweight and Obesity, run by Scholar Rock, Inc. at 7 sites in United States.
Trial summary
A phase 2 study to evaluate the effects of apitegromab as an adjunctive therapy to GLP-1 receptor agonist therapy in subjects with overweight or obesity Read more about this study
- Who is it for?
- Ages 18 to 65 yearsHealthy volunteers can take part
- Conditions the study is for
- Overweight and Obesity
- What is being tested?
- Apitegromab and Tirzepatide
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 102 participants
- Where
- 7 sitesUnited States
- Study dates
- 21 May 2024to 17 Jun 2025
- Phase
- Phase 2
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 65 years
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- Able to comprehend the informed consent process and provide written informed consent prior to study enrollment and the conduct of any study-related assessments to study enrollment and the conduct of any study-related assessments
- Male or female, age ≥ 18 and ≤ 65 years at the time of informed consent
- Stable body weight (±5 kg) within 90 days of Screening
- At Screening, a BMI of:
- ≥30.0 kg/m2 to ≤45.0 kg/m2 or
- ≥27.0 kg/m2 to <30.0 kg/m2 with the presence of 1 or more weight-related comorbid condition(s). Note: See exclusion criteria for specific organ class disease parameters
Who cannot join
- History of or active cardiovascular, neurovascular, peripheral vascular, pulmonary, hepatic, pancreatic, neuromuscular, and/or psychiatric disease
- Active malignancy, other than local subcutaneous squamous cell and basal cell carcinomas
- History of immunosuppressive, chemotherapeutic, or radiation treatment within 12 months prior to Screening
- History of Type 1 diabetes or active Type 2 diabetes (T2D). If there was a history of T2D and it resolved, then the resolution must have occurred >12 months prior to Screening. Prediabetes managed with nonpharmacologic approaches (exercise and diet) is not an exclusion
Trial locations and contacts
7 sites in 1 country.
7 sites in 1 country
United States7 sites
Apex Mobile Clinical Research
Bellaire, Texas, 77401
Great Lakes Clinical Trials, LLC d/b/a Flourish Research
Chicago, Illinois, 60640
ProSciento CRU
Chula Vista, California, 91911
Tandem Clinical Research GI, LLC
Marrero, Louisiana, 70072
Alliance for Multispecialty Research, LLC
Norman, Oklahoma, 73069
AdventHealth Translational Research Institute
Orlando, Florida, 32804
Clinical Trials of Texas, LLC dba Flourish Research
San Antonio, Texas, 78229
About this study
Official title: A Phase 2 Randomized, Double-blind, Placebo-controlled, Multicenter Study to Evaluate the Efficacy, Safety and Pharmacokinetics of Apitegromab in Overweight and Obese Adult Subjects
A phase 2 study to evaluate the effects of apitegromab as an adjunctive therapy to GLP-1 receptor agonist therapy in subjects with overweight or obesity
Read the detailed description
This phase 2 randomized, double-blind, placebo-controlled, multicenter study assessed the safety, efficacy, and pharmacokinetics (PK) of apitegromab when used as an adjunctive therapy to GLP-1 receptor agonist therapy in subjects with overweight and obesity and without diabetes. Each subject received tirzepatide throughout the treatment period. In addition, all subjects were randomized 1:1 to receive either apitegromab or placebo during the treatment period.
- Conditions
- Overweight and Obesity
- Being tested
- Apitegromab, Placebo, Tirzepatide
- Keywords
- Overweight, Obesity
- Medical subject headings
- Overweight, Obesity
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
ApitegromabDrug
Also called SRK-015
Apitegromab (SRK-015) is a fully human anti-proMyostatin monoclonal antibody (mAb) that specifically binds to human pro/latent myostatin, inhibiting myostatin activation. Apitegromab was administered every 4 weeks by intravenous (IV) infusion.
PlaceboDrug
Same appearance and composition as apitegromab drug product but does not contain the active ingredient. Placebo was administered every 4 weeks by intravenous (IV) infusion.
TirzepatideDrug
Also called ZEPBOUND
Glucose-dependent insulinotropic polypeptide (GIP) receptor and glucagon-like peptide-1 (GLP-1) receptor agonist. Tirzepatide was administered every week by subcutaneous injection.
| Study group | Role | What they receive |
|---|---|---|
| Cohort 1 | Experimental | Apitegromab + incretin mimetic Receives: Drug: Apitegromab; Drug: Tirzepatide |
| Cohort 2 | Placebo comparator | Placebo + incretin mimetic Receives: Drug: Placebo; Drug: Tirzepatide |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change from Baseline in total Lean Body Mass (kg) at 24 weeks
Dual-energy X-ray absorptiometry was used to evaluate body composition
Measured: Baseline and 24 weeks
Secondary outcomes (10)
Change from Baseline in body weight
Total body weight was assessed via a calibrated scale
Measured: Baseline and 24 weeks
Change from Baseline in percent lean body mass (%)
Dual-energy X-ray absorptiometry was used to evaluate body composition
Measured: Baseline and 24 weeks
Change from Baseline in fat body mass (kg and %)
Dual-energy X-ray absorptiometry was used to evaluate body composition
Measured: Baseline and 24 weeks
Change from Baseline in visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), and trunk fat body mass (kg and %)
Dual-energy X-ray absorptiometry was used to evaluate body composition
Measured: Baseline and 24 weeks
Percent (%) of weight loss from baseline due to fat body mass loss
Dual-energy X-ray absorptiometry was used to evaluate body composition
Measured: Baseline and 24 weeks
Percent (%) of weight loss from baseline due to lean body mass loss
Dual-energy X-ray absorptiometry was used to evaluate body composition
Measured: Baseline and 24 weeks
Concentration of apitegromab in circulation over time
Blood samples were assessed for circulating concentration of apitegromab
Measured: Baseline up to 40 weeks
Concentration of latent myostatin in circulation over time
Blood samples were assessed for circulating concentration of latent myostatin
Measured: Baseline up to 24 weeks
Treatment emergent adverse events (TEAEs) and serious adverse events (SAEs)
Incidence and severity of TEAEs and SAEs
Measured: Baseline up to 40 weeks
Presence of anti-drug antibodies (ADA) against apitegromab over time
Measured in serum blood samples
Measured: Baseline up to 40 weeks
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted6 Jun 2024
- Study start21 May 2024
- Primary completion4 Mar 2025
- Study completion17 Jun 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Overweight and ObesityStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 2
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- Parallel Assignment
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 102 participants (actual)
Sponsor and investigators
- Lead sponsor
- Scholar Rock, Inc.
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06445075
- Sponsor's protocol ID
- SRK-015-006
- Acronym
- EMBRAZE
- Status last verified
- Jan 2026
- First submitted
- 22 May 2024
- Last updated
- 23 Jan 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- Yes
Publications
Pratley RE, Denham DS, Trivedi R, Watkins E, Connery L, Barnes J, Yu D, Hong J, Simard C, Umans K, Liu L, Tirucherai GS, Marantz JL. Apitegromab for lean mass preservation during tirzepatide-induced weight loss: a randomized, double-blind, placebo-controlled phase 2 trial. Nat Med. 2026 Jul;32(7):2673-2678. doi: 10.1038/s41591-026-04440-4. Epub 2026 Jun 8.
PubMed 42260100
Study at a glance
From the registry record, last updated by the sponsor on 23 Jan 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Phase 2 Randomized, Double-blind, Placebo-controlled, Multicenter Study to Evaluate the Efficacy, Safety and Pharmacokinetics of Apitegromab in Overweight and Obese Adult Subjects
- ClinicalTrials.gov ID
- NCT06445075
- Acronym / sponsor ID
- EMBRAZE / SRK-015-006
- Conditions
- Overweight and Obesity
- Keywords
- Overweight, Obesity
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 102 participants (actual)
- Lead sponsor
- Scholar Rock, Inc.Industry (pharma, biotech, devices)
- Study start
- 21 May 2024 (actual)
- Primary completion
- 4 Mar 2025 (actual)
- Study completion
- 17 Jun 2025 (actual)
- First posted
- 6 Jun 2024 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
A phase 2 study to evaluate the effects of apitegromab as an adjunctive therapy to GLP-1 receptor agonist therapy in subjects with overweight or obesity
Detailed description
This phase 2 randomized, double-blind, placebo-controlled, multicenter study assessed the safety, efficacy, and pharmacokinetics (PK) of apitegromab when used as an adjunctive therapy to GLP-1 receptor agonist therapy in subjects with overweight and obesity and without diabetes. Each subject received tirzepatide throughout the treatment period. In addition, all subjects were randomized 1:1 to receive either apitegromab or placebo during the treatment period.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind (participant, care provider, investigator, outcomes assessor)
- Number of arms
- 2
- Model description
- Parallel Assignment
| Arm | Type | Receives |
|---|---|---|
| Cohort 1 | Experimental | Drug: Apitegromab, Drug: TirzepatideApitegromab + incretin mimetic |
| Cohort 2 | Placebo comparator | Drug: Placebo, Drug: TirzepatidePlacebo + incretin mimetic |
Who may qualify
- Ages
- 18 to 65 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (6 listed)
- Able to comprehend the informed consent process and provide written informed consent prior to study enrollment and the conduct of any study-related assessments to study enrollment and the conduct of any study-related assessments
- Male or female, age ≥ 18 and ≤ 65 years at the time of informed consent
- Stable body weight (±5 kg) within 90 days of Screening
- At Screening, a BMI of:
Key exclusion criteria (4 listed)
- History of or active cardiovascular, neurovascular, peripheral vascular, pulmonary, hepatic, pancreatic, neuromuscular, and/or psychiatric disease
- Active malignancy, other than local subcutaneous squamous cell and basal cell carcinomas
- History of immunosuppressive, chemotherapeutic, or radiation treatment within 12 months prior to Screening
- History of Type 1 diabetes or active Type 2 diabetes (T2D). If there was a history of T2D and it resolved, then the resolution must have occurred >12 months prior to Screening. Prediabetes managed with nonpharmacologic approaches (exercise and diet) is not an exclusion
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| ApitegromabAlso: SRK-015Apitegromab (SRK-015) is a fully human anti-proMyostatin monoclonal antibody (mAb) that specifically binds to human pro/latent myostatin, inhibiting myostatin activation. Apitegromab was administered every 4 weeks by intravenous (IV) infusion. | Drug | Cohort 1 |
| PlaceboSame appearance and composition as apitegromab drug product but does not contain the active ingredient. Placebo was administered every 4 weeks by intravenous (IV) infusion. | Drug | Cohort 2 |
| TirzepatideAlso: ZEPBOUNDGlucose-dependent insulinotropic polypeptide (GIP) receptor and glucagon-like peptide-1 (GLP-1) receptor agonist. Tirzepatide was administered every week by subcutaneous injection. | Drug | Cohort 1, Cohort 2 |
Primary outcome
Change from Baseline in total Lean Body Mass (kg) at 24 weeks
Time frame: Baseline and 24 weeks
Dual-energy X-ray absorptiometry was used to evaluate body composition
10 secondary outcomes
Change from Baseline in body weight
Time frame: Baseline and 24 weeks
Change from Baseline in percent lean body mass (%)
Time frame: Baseline and 24 weeks
Change from Baseline in fat body mass (kg and %)
Time frame: Baseline and 24 weeks
Change from Baseline in visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), and trunk fat body mass (kg and %)
Time frame: Baseline and 24 weeks
Percent (%) of weight loss from baseline due to fat body mass loss
Time frame: Baseline and 24 weeks
Percent (%) of weight loss from baseline due to lean body mass loss
Time frame: Baseline and 24 weeks
Concentration of apitegromab in circulation over time
Time frame: Baseline up to 40 weeks
Concentration of latent myostatin in circulation over time
Time frame: Baseline up to 24 weeks
Treatment emergent adverse events (TEAEs) and serious adverse events (SAEs)
Time frame: Baseline up to 40 weeks
Presence of anti-drug antibodies (ADA) against apitegromab over time
Time frame: Baseline up to 40 weeks
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 23 Jan 2026.
- Derived from this study: PubMed 42260100Pratley RE, Denham DS, Trivedi R, Watkins E, Connery L, Barnes J, Yu D, Hong J, Simard C, Umans K, Liu L, Tirucherai GS, Marantz JL. Apitegromab for lean mass preservation during tirzepatide-induced weight loss: a randomized, double-blind, placebo-controlled phase 2 trial. Nat Med. 2026 Jul;32(7):2673-2678. doi: 10.1038/s41591-026-04440-4. Epub 2026 Jun 8.
- Individual participant dataSharing planned: Yes
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
7 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing Apitegromab and Tirzepatide in people with Overweight and Obesity, run by Scholar Rock, Inc. at 7 sites in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 6 inclusion and 4 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 23 Jan 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 7 sites in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change from Baseline in total Lean Body Mass (kg) at 24 weeks (time frame: Baseline and 24 weeks). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT06445075, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 23 Jan 2026.