A Study to Learn About the Monthly Dosing Study Medicine Called Berobenatide in Adults With Breathing Problems During Sleep and Overweight or Obesity Who Do Not Use a Breathing Machine (PAP) (VESPER-OSA 2) (VESPER-OSA 2)

A PHASE 3, RANDOMIZED, DOUBLE-BLIND, PLACEBO-CONTROLLED STUDY TO ASSESS THE EFFICACY AND SAFETY OF ONCE-MONTHLY BEROBENATIDE IN ADULTS WITH OBSTRUCTIVE SLEEP APNEA AND OVERWEIGHT OR OBESITY NOT RECEIVING POSITIVE AIRWAY PRESSURE THERAPY (VESPER-OSA 2)

This study is being done to learn about the safety and effects of a study medicine called berobenatide (bear-oh-BEN-uh-tide). The study will see if berobenatide can help adults with breathing problems during sleep (obstructive sleep apnea [OSA]) and overweight or obesity who are not using a breathing machine (positive airway pressure [PAP] machine).

People may be able to take part if they are adults with moderate to severe OSA, have overweight or obesity, and have been unable or unwilling using PAP therapy before joining the study. Participants will be assigned by chance to receive either berobenatide or a placebo (a treatment that looks like the study medicine but contains no active medicine). The study treatment will be given as an injection under the skin approximately once a month. Participants will receive study treatment at study sites and may administer some doses at home after receiving training.

During the study, participants will attend study visits, undergo sleep studies, complete questionnaires, and have health assessments performed. Researchers will compare the effects of berobenatide and placebo on sleep apnea, body weight, and other health measures.

Study Overview

• Status: Recruiting
• Conditions: Apnea; Sleep Disorders; Overweight and/or Obesity
• Intervention / Treatment: Drug: Berobenatide; Drug: Placebo

• Study Type: Interventional
• Enrollment (Estimated): 258
• Phase: Phase 3

Contacts and Locations

• Study Contact: Name: Pfizer CT.gov Call Center; Phone Number: 1-800-718-1021; Email: ClinicalTrials.gov_Inquiries@pfizer.com

Study Locations

• United States
  • Alabama
    • Cullman, Alabama, United States, 35055
      • Recruiting
      • Cullman Clinical Trials
  • Florida
    • Bradenton, Florida, United States, 34209
      • Recruiting
      • DM Clinical Research-Bradenton
  • Minnesota
    • Maplewood, Minnesota, United States, 55109
      • Recruiting
      • Headlands Research - Twin Cities
  • Texas
    • Tomball, Texas, United States, 77375
      • Not yet recruiting
      • DM Clinical Research-Tomball

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Adults aged 18 years or older
• Body mass index (BMI) ≥27 kg/m² at screening
• Previously diagnosed with moderate to severe obstructive sleep apnea (OSA)
• Unable or unwilling to use positive airway pressure (PAP) therapy, and no use of PAP therapy for at least 4 weeks prior to screening

Exclusion Criteria:

• Self-reported body weight change of more than 5% within 90 days prior to screening
• Diagnosis of any type of diabetes (resolved gestational diabetes is permitted)
• History of acute or chronic pancreatitis
• Personal or family history of medullary thyroid carcinoma (MTC) or multiple endocrine neoplasia type 2 (MEN 2) Sleep-disordered breathing conditions other than obstructive sleep apnea that could interfere with study assessments or interpretation of results (eg, central sleep apnea, mixed sleep apnea, Cheyne-Stokes respiration, obesity hypoventilation syndrome, or significant craniofacial abnormalities).

Study Plan

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Berobenatide; Participants receive berobenatide by subcutaneous injection.	Drug: Berobenatide; Subcutaneous injection; Other Names: PF-08653944; MET097
Placebo Comparator: Placebo; Participants receive volume-matched placebo	Drug: Placebo; Volume-matched subcutaneous placebo.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change From Baseline in Apnea-Hypopnea Index	Apnea-Hypopnea Index is the number of apnea and hypopnea events per hour of sleep, assessed by polysomnography.	Baseline, Week 52

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change From Baseline in Body Weight		Baseline, Week 52
Change From Baseline in Waist Circumference		Baseline, Week 52
Percent Change From Baseline in Body Weight		Baseline, Week 52
Percentage of Participants With Improvement in Patient Global Impression of Severity (PGI-S) Sleepiness Category		Week 52
Percentage of Participants With Improvement in Patient Global Impression of Severity (PGI-S) Fatigue Category		Week 52
Percentage of Participants Reporting Improvement in Patient Global Impression of Change (PGI-C) Sleepiness		Week 52
Percentage of Participants Reporting Improvement in Patient Global Impression of Change (PGI-C) Fatigue		Week 52
Percentage of Participants Reporting Improvement in Patient Global Impression of Change (PGI-C) Sleep Quality		Week 52
Percentage of Participants Reporting Improvement in Patient Global Impression of Change (PGI-C) Snoring		Week 52
Number of participants with Treatment-Emergent Adverse Event (TEAE)		Week 52
Number of participants with Serious Adverse Event (SAE)		Week 52
Number of participants with Adverse event (AE) leading to permanent discontinuation from study intervention or study		Week 52
Number of participants with Adverse Events of Special Interest (AESI)		Week 52
Number of participants with clinical laboratory abnormalities		Week 52
Change From Baseline in Low-density lipoprotein cholesterol (LDL-C)		Baseline, week 52
Change From Baseline in High-Sensitivity C-Reactive Protein		Baseline, Week 52
Percent Change From Baseline in Apnea-Hypopnea Index		Baseline, Week 52
Percentage of Participants With at Least 50% Reduction in Apnea-Hypopnea Index		Week 52
Change From Baseline in Sleep-Apnea-Specific Hypoxic Burden (SASHB)		Baseline, Week 52
Percentage of Participants With Obstructive Sleep Apnea Remission or Mild Non-Symptomatic Obstructive Sleep Apnea		Week 52
Change From Baseline in Systolic Blood Pressure		Baseline, Week 52
Change From Baseline in Patient-Reported Outcomes Measurement Information System (PROMIS) Sleep-Related Impairment 8a T-Score		Baseline, Week 52
Change From Baseline in PROMIS Sleep Disturbance 8b T-Score		Baseline, Week 52
Percentage of Participants with AHI <5		Week 52
Percentage of Participants with AHI 5-14 with ESS (Epworth Sleepiness Scale) ≤10		Week 52
Percentage of participants with AHI less then 15		Week 52
Change From Baseline in Epworth Sleepiness Scale Total Score		Baseline, Week 52
Change From Baseline in Impact of Weight on Quality of Life-Lite Clinical Trials (IWQOL-Lite-CT) Physical Function Composite Score		Baseline, Week 52
Change From Baseline in IWQOL-Lite-CT Physical Composite Score		Baseline, Week 52
Change From Baseline in IWQOL-Lite-CT Psychosocial Composite Score		Baseline, Week 52
Change From Baseline in IWQOL-Lite-CT Total Score	Score ranges from 0 to 100; higher scores indicate better quality of life.	Baseline, Week 52
Change From Baseline in Body Mass Index		Baseline, Week 52
Change From Baseline in Neck Circumference		Baseline, Week 52
Change From Baseline in Short Form 36-Item (SF-36)		Baseline, Week 52
Percentage of Participants With Improvement in Patient Global Impression of Severity (PGI-S) Snoring Category		Week 52
Change From Baseline in EuroQol 5-Dimension, 5-Level (EQ-5D-5L) Index Score		Baseline, Week 52
Change From Baseline in EuroQol-visual analog scale (EQ-VAS) Score		Baseline, Week 52
Change From Baseline in WPAI:GH Presenteeism Score		Baseline, Week 52
Change From Baseline in WPAI:GH Work Productivity Loss Score		Baseline, Week 52
Change From Baseline in WPAI:GH Activity Impairment Score		Baseline, Week 52
Change From Baseline in Diastolic Blood Pressure		Baseline, Week 52
Change From Baseline in Total Cholesterol		Baseline, Week 52
Change From Baseline in High-density lipoprotein cholesterol (HDL-C)		Baseline, Week 52
Change From Baseline in Non-HDL Cholesterol		Baseline, Week 52
Change From Baseline in Very low-density lipoprotein cholesterol (VLDL) Cholesterol		Baseline, Week 52
Change From Baseline in Triglycerides		Baseline, Week 52

Collaborators and Investigators

• Sponsor: Pfizer
• Investigators: Study Director: Pfizer CT.gov Call Center, Pfizer

Publications and helpful links

Helpful Links

• <p>To obtain contact information for a study center near you, click here.</p>

Study record dates

Study Major Dates

• Study Start (Actual): October 19, 2026
• Primary Completion (Estimated): June 1, 2028
• Study Completion (Estimated): July 20, 2028

Study Registration Dates

• First Submitted: October 9, 2026
• First Submitted That Met QC Criteria: October 15, 2026
• First Posted (Actual): October 19, 2026

Study Record Updates

• Last Update Posted (Actual): November 6, 2026
• Last Update Submitted That Met QC Criteria: November 4, 2026
• Last Verified: November 1, 2026

More Information

Terms related to this study

• Keywords: OSA; Obstructive Sleep Apnea; Sleep Apnea; Polysomnography; Sleep Disorder; PSG; Sleep Study; Snoring; Excessive Daytime Sleepiness; Daytime Sleepiness; Sleep Problems; Breathing Disorder; Breathing Stops During Sleep
• Additional Relevant MeSH Terms: Neurologic Manifestations; Nervous System Diseases; Mental Disorders; Respiratory Tract Diseases; Respiration Disorders; Signs and Symptoms, Respiratory; Sleep Disorders, Intrinsic; Dyssomnias; Respiratory Sounds; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Parasomnias; Sleep Apnea Syndromes; Sleep Apnea, Obstructive; Apnea; Sleep Wake Disorders; Snoring; Dyspnea; Disorders of Excessive Somnolence
• Other Study ID Numbers: C6491021; VESPER-OSA 2 (Other Identifier: Alias Study Number)

Plan for Individual participant data (IPD)

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

IPD Plan Description

Pfizer will provide access to individual de-identified participant data and related study documents (e.g. protocol, Statistical Analysis Plan (SAP), Clinical Study Report (CSR)) upon request from qualified researchers, and subject to certain criteria, conditions, and exceptions. Further details on Pfizer's data sharing criteria and process for requesting access can be found at: https://www.pfizer.com/science/clinical_trials/trial_data_and_results/data_requests.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No