A 2-part, Phase 1b Clinical Study Designed to Evaluate the Safety, PK, and Efficacy of CRB-913 in Participants With Obesity (CANYON-1)

A Phase 1b, Randomized, Double-Blind, Placebo-Controlled, Dose-Range Finding Study of the Efficacy, Safety, and Pharmacokinetics of CRB-913 in Participants With Obesity With a Single Cohort Open-label Exploratory Pharmacokinetic Lead-In

This study will assess the safety of the investigational drug CRB-913 and how it is processed in the body.

The study has two parts: Part 1 will measure drug levels in healthy adults after taking CRB-913 tablets, and Part 2 will compare three doses of CRB-913 with placebo to evaluate safety, effects on body weight, and drug levels in the blood.

Part 2 is blinded, meaning participants, study doctors, and the sponsor will not know which treatment is given.

Participants in Part 2 will take study treatment for 12 weeks and will be followed for 28 days after treatment ends.

Study Overview

• Status: Active, not recruiting
• Conditions: Obese But Otherwise Healthy Participants
• Intervention / Treatment: Drug: CRB-913; Drug: Placebo

Detailed Description

CRB-913 is a novel cannabinoid receptor type 1 (CB1) inverse agonist (CB1-IA) that is being developed for once-daily treatment of obesity.

This study will look at how the investigational drug CRB-913 behaves in the body and how it affects body weight.

The study has two parts:

Part 1 will include healthy adult participants. They will receive CRB-913 in tablet form. Researchers will measure how much of the drug enters the bloodstream and how long it stays there.

Part 2 will include participants who will receive one of three different doses of CRB-913 or a placebo (a tablet with no active drug). This part of the study will look at the safety of CRB-913 and its effects on body weight. Researchers will also measure the amount of CRB-913 in the blood.

Part 2 is blinded, which means that participants, study doctors, and the study sponsor will not know who is receiving CRB-913 or placebo.

All participants in Part 2 will take their assigned study tablets for 12 weeks, followed by a 28-day follow-up period after treatment ends.

The information collected in this study will help determine whether CRB-913 is safe, how the body processes it, and whether it may help with weight-related outcomes.

• Study Type: Interventional
• Enrollment (Estimated): 252
• Phase: Phase 1

Contacts and Locations

Study Locations

• United States
  • Alabama
    • Birmingham, Alabama, United States, 35209
      • Central Alabama Research
  • Arizona
    • Chandler, Arizona, United States, 85225
      • Arizona Clinical Trials
  • California
    • Rancho Cucamonga, California, United States, 91730
      • Prospective Research Innovations
  • Florida
    • DeLand, Florida, United States, 32720
      • Accel Research Sites
    • Largo, Florida, United States, 33761
      • Tampa Bay Medical Research
    • Miami, Florida, United States, 33126
      • Quotient Sciences
  • Kentucky
    • Louisville, Kentucky, United States, 40213
      • Louisville Metabolic and Atherosclerosis Research Center
  • Nevada
    • Las Vegas, Nevada, United States, 89109
      • Alliance Clinical
  • New York
    • Cedarhurst, New York, United States, 11516
      • Neurobehavioral Research
    • Rochester, New York, United States, 14609
      • Rochester Clinical Research
  • North Carolina
    • Morehead City, North Carolina, United States, 28557
      • Lucas Research
  • Ohio
    • Cincinnati, Ohio, United States, 45227
      • Medpace Clinical Pharmacology
    • Cleveland, Ohio, United States, 44122
      • Velocity Clinical Research
  • Texas
    • Dallas, Texas, United States, 75230
      • Velocity Clinical Research
    • San Antonio, Texas, United States, 78229
      • Flourish Research

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Part 1: Participants with BMI 18.0-25.0 kg/m²
• Part 2: Obese participants with BMI ≥30 kg/m²

Exclusion Criteria:

• Significant liver disease or moderate-severe hepatic impairment
• History of seizures, epilepsy, or intracranial surgery
• Diabetes mellitus (Type 1 or Type 2), except gestational
• Bariatric surgery or >5 kg weight change in past 3 months
• Recent use (within 3 months) of GLP-1 agonists or other weight-loss medications
• Major depression within 2 years.
• Any history of suicidal ideation/attempt
• Severe psychiatric disorders (e.g., schizophrenia, bipolar disorder)
• Elevated screening scores: PHQ-9 >4, GAD-7 >4, or positive C-SSRS Items 1-2
• Active or recent (within 5 years) malignancy (exceptions: in situ and fully resected nonmelanoma skin cancer)
• Abnormal thyroid function: TSH >6 mIU/L unless stable on replacement therapy
• QTc >470 msec (females) or >450 msec (males) or history of long QT syndrome
• Use of systemic corticosteroids or unstable chronic medications affecting BP, lipids, or glucose
• Use of CYP3A4 substrates or strong P-gp substrates/inhibitors
• Investigational drug use within 28 days
• Prior exposure to CRB-913 or other CB1 inverse agonists/antagonists
• Substance abuse history
• Pregnancy, breastfeeding, or unwillingness to use highly effective contraception
• Positive drug or alcohol screen
• Any condition that, in the investigator's judgment, makes participation unsafe or non-feasible

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

5

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Part 1: PK Lead-in; Primary Treatment Period (Day 1): Participants will receive a single dose of CRB-913. Following Part 1 of the study Part 2 will open for recruitment. Safety Follow-up Period: Participants who complete or discontinue the primary treatment period are followed for safety for 28 days. No treatment is administered during this period.	Drug: CRB-913; Administered QD
Experimental: Part 2: CRB-913 low dose; Primary Treatment Period (Day 0-Day 85): Participants will receive CRB-913 low dose which is maintained up to day 85. Safety Follow-up Period: Participants who complete or discontinue the primary treatment period are followed for safety for 28 days. No treatment is administered during this period.	Drug: CRB-913; Administered QD
Experimental: Part 2: CRB-913 Medium Dose; Primary Treatment Period (Day 0-Day 85): Participants will receive CRB-913 starting at low dose for 14 days and increasing to medium dose at day 15 which is maintained up to day 85. Safety Follow-up Period: Participants who complete or discontinue the primary treatment period are followed for safety for 28 days. No treatment is administered during this period.	Drug: CRB-913; Administered QD
Experimental: Part 2: CRB-913 High Dose; Primary Treatment Period (Day 0 - Day 85): Participants will receive CRB-913 starting at low dose for 14 days, increasing to medium dose at day 15 for 14 days and then increased to high dose at day 29 which is maintained up to day 85. Safety Follow-up Period: Participants who complete or discontinue the primary treatment period are followed for safety for 28 days. No treatment is administered during this period.	Drug: CRB-913; Administered QD
Placebo Comparator: Part 2: Placebo; Primary Treatment Period (Day 0-Day 85): Participants will receive CRB-913 matching placebo which is maintained up to day 85. Safety Follow-up Period: Participants who complete or discontinue the primary treatment period are followed for safety for 28 days. No treatment is administered during this period.	Drug: Placebo; Administered QD

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Part 1: To evaluate the PK of a single dose of CRB-913 - Cmax	Maximum plasma concentration (Cmax)	0 to 48 hours
Part 1: To evaluate the PK of a single dose of CRB-913 - Tmax	Time to maximum plasma concentration (Tmax)	0 to 48 hours
Part 1: To evaluate the PK of a single dose of CRB-913 - T1/2	Terminal elimination half-life (T1/2)	0 to 48 hours
Part 2: To evaluate the safety of CRB-913 - TEAE	Incidence and severity of treatment emergent adverse events	Day 1 to 28 days post final dose
Part 2: To evaluate the safety of CRB-913 - AESI	Incidence of adverse events of special interest	Day 1 to 28 days post final dose

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Part 1: To evaluate the safety of a single dose of CRB-913 - TEAE	Incidence and severity of treatment emergent adverse events	Day 1 to 28 days post final dose
Part 2: To evaluate the effect of CRB-913 on weight	Mean change in absolute body weight from baseline to End of Treatment (EOT) compared to placebo	Day 1 to 28 days post final dose
Part 2: To evaluate the PK of CRB-913 - Cmax	Maximum plasma concentration (Cmax)	Day 1 to 28 days post final dose
Part 2: To evaluate the PK of CRB-913 - Tmax	Time to maximum plasma concentration (Tmax)	Day 1 to 28 days post final dose

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Part 2: To evaluate changes in food noise	Mean change from baseline in food noise questionnaire (FNQ) score	Day 1 to 28 days post final dose

Collaborators and Investigators

• Sponsor: Corbus Pharmaceuticals Inc.
• Investigators: Principal Investigator: Leela Vrishabhendra, MD, Medpace Clinical Pharmacology

Study record dates

Study Major Dates

• Study Start (Actual): December 4, 2025
• Primary Completion (Estimated): July 2, 2026
• Study Completion (Estimated): July 31, 2026

Study Registration Dates

• First Submitted: December 16, 2025
• First Submitted That Met QC Criteria: December 16, 2025
• First Posted (Actual): December 30, 2025

Study Record Updates

• Last Update Posted (Actual): May 29, 2026
• Last Update Submitted That Met QC Criteria: May 27, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: Obesity; Overweight; Body Weight; Metabolic Diseases; Endocrine System Diseases; Nutrition Disorders; Nutritional and Metabolic Diseases; Cannabinoid-1 receptor inverse agonist
• Additional Relevant MeSH Terms: Overnutrition; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Overweight; Obesity; Body Weight; Metabolic Diseases; Nutrition Disorders; Endocrine System Diseases; Nutritional and Metabolic Diseases
• Other Study ID Numbers: CRB-913-02

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No