Livoletide for the Treatment of PWS

The ZEPHYR study has completed enrollment of the phase 2b study for ages 8 to 65.
Patients ages 4 to 7 with hyperphagia and a minimum weight of 20kg may still enroll.


Study Purpose

Livoletide (AZP-531) is a first-in-class analogue of unacylated ghrelin (UAG), a naturally occurring hormone that is thought to counteract the effects of acylated ghrelin (AG). ZEPHYR is a randomized, double-blind placebo-controlled study investigating Livoletide, which has been divided into two parts. The first part is a Phase 2b dose-response study consisting of a 3-month double-blind, placebo-controlled Core Period in which patients receive one of two doses of livoletide or placebo, followed by a 9-month Extension Period in which all patients will receive livoletide. The second part is a Phase 3 study consisting of a 6-month double-blind, placebo-controlled Core Period in which patients receive livoletide or placebo, followed by a 6-month Extension Period in which all patients will receive livoletide. The Phase 3 may be initiated following review of the safety and efficacy results at the completion of the Phase 2b Core Period.   

A webinar sharing details on this study was recorded April, 2019. You can watch the webinar below or read a transcription of the webinar on our blog

Recruitment Criteria

Status: recruiting
Eligible Ages: 4 - 65 years
Other Criteria: BMI < 65 kg/m2

Trial Details

ClinicalTrials.Gov IdentifierNCT03790865
Phase: 2b/3
Duration: Phase 2b will be 3 months followed by 9 month open label extension, Phase 3 will be 6 months double blind followed by 6-month open label extension
Lead Sponsor: Millendo Therapeutics SAS
Countries: United States, France, Spain, Italy, Belgium, Netherlands, Australia, United Kingdom
Additional Details: 

Eligibility Criteria

Inclusion Criteria:

  • Ages 4 to 65
  • Diagnosis of PWS confirmed by DNA methylation test
  • Evidence of increased appetite or hyperphagia
  • Patient must have a single primary caregiver who should be available for the duration of the study
  • BMI ≤ 65 kg/m2
  • Growth hormone treatment permitted if doses are stable

Exclusion Criteria:

  • History of chronic liver disease
  • Type 1 diabetes mellitus
  • HbA1c > 10%

Outcome Measures

This study will evaluate the drugs efficacy on the following:

Primary Outcome Measure:

  • Change in hyperphagia and food-related behaviors (Hyperphagia Questionnaire for Clinical Trials; HQ-CT): Change from baseline to the end of the 3-month Core Period for HQ-CT total score. The HQ-CT score range is 0 to 36 where the higher score represents more severe abnormal food-related behaviors.

Secondary Outcome Measures:

  • Change in fat mass: Percentage change from baseline to the end of the 3-month Core Period in total body fat mass in overweight/obese patients with PWS
  • Change in waist circumference: Change from baseline to the end of the 3-month Core Period in waist circumference in overweight/obese patients with PWS
  • Change in body weight: Percentage change from baseline to the end of the 3-month Core Period in body weight in overweight/obese patients with PWS

This study will be available at the following sites:


United States, Alabama

University of Alabama at Birmingham                                                                   
Birmingham, Alabama, United States, 35233
Contact: Hussein Abdul-Latif, MD         

United States, California

University of California - Irvine Medical Center                                               
Orange, California, United States, 92868
Contact: Virginia Kimonis, MD         

Rady Children's Hospital - San Diego                                                                      
San Diego, California, United States, 92123
Contact: Lynne Bird, MD         

United States, Colorado

Children's Hospital Colorado                                                                                        
Denver, Colorado, United States, 80045
Contact: Shawn McCandless, MD         

United States, Kansas

University of Kansas Medical Center                                                                       
Kansas City, Kansas, United States, 66160
Contact: Merlin Butler, MD         

United States, Maryland

Johns Hopkins University                                                                                                
Baltimore, Maryland, United States, 21287
Contact: Ann Scheimann, MD         

United States, Massachusetts

Boston Children's Hospital
Boston, Massachusetts, United States, 02215
Contact: Amy Fleischman, MD         

United States, Michigan

University of Michigan  
Ann Arbor, Michigan, United States, 48109
Contact: Dan Shumer, MD         

United States, Minnesota

Children's Hospitals and Clinics of Minnesota-Minneapolis
Saint Paul, Minnesota, United States, 55102
Contact: Jennifer Abuzzahab, MD         

United States, New York

Winthrop University Hospital
Mineola, New York, United States, 11501
Contact: Moris Angulo, MD         

New York Presbyterian Morgan Stanley Children's Hospital
New York, New York, United States, 10032
Contact: Wendy Chung, MD         

United States, Tennessee

Vanderbilt University Medical Center
Nashville, Tennessee, United States, 37232
Contact: Italo Biaggioni, MD         

United States, Texas

University of Texas Southwestern Medical Center 
Dallas, Texas, United States, 75390
Contact: Olga Gupta, MD         

Baylor College of Medicine 
Houston, Texas, United States, 77030
Contact: Kathy Hwu, MD         

United States, Washington

Seattle Children's Hospital    
Seattle, Washington, United States, 98105
Contact: Parisa Salehi, MD         


Royal Prince Alfred Hospital    
Camperdown, Australia, 2050
Contact: Tania Markovic, MD         

Austin Health    
Melbourne, Australia, 3084
Contact: Elif Ekinci, MD         


Cliniques Universitaires Saint-Luc   
Brussels, Belgium, 1200
Contact: Veronique Beauloye, PhD         


Centre Hospitalier Universitaire d'Angers     
Angers, France, 49100
Contact: Regis Coutant, MD         

Centre Hospitalier Universitaire d'Angers    
Angers, France, 49100
Contact: Frederic Illouz, MD         

CHU Lyon - Hopital Femmes Mere Enfant       
Bron, France, 69677
Contact: Marc Nicolino, MD         

Hospital Pitie Salpetriere          
Paris, France, 75013
Contact: Christine Poitou-Bernert, MD         

Hopital Necker-Enfants Malades                 
Paris, France, 75015
Contact: Graziella Pinto, MD         

CHU de Toulouse - Hospital Rangueil      
Toulouse, France, 31059
Contact: Patrick Ritz, MD         

CHU de Toulouse - Hopital des Enfants              
Toulouse, France
Contact: Maithe Tauber, MD         


Azienda Ospedaliera Universitaria Federico II 
Napoli, Italy, 80131
Contact: Graziano Grugni, MD         

Azienda Ospedaliera Universitaria Federico II 
Napoli, Italy, 80131
Contact: Anna Maria Colao, MD         


Erasmus University Medical Center 
Rotterdam, Netherlands, 3015
Contact: Laura De Graaff-Herder, MD         

Stichting Kind en Groei        
Rotterdam, Netherlands, 3016
Contact: Anita Hokken-Koelega, MD         


Hospital General Universitario de Alicante
Alicante, Spain, 03010
Contact: Antonio Pico Alfonso, MD         

Hospital Sant Joan de Deu  
Barcelona, Spain, 08950
Contact: Marta Ramón, MD         

Corporacio Sanitaria Parc Tauli - Hospital de Sabadell 
Sabadell, Spain, 08208
Contact: Assumpta Caixàs, MD         

United Kingdom

NHS Tayside 
Dundee, United Kingdom, DD1 9SY
Contact: Nicholas Conway, MD         

Imperial College London 
London, United Kingdom, W12 0NN
Contact: Tony Goldstone, MD         


More information on the Zephyr clinical trial can be obtained at





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