Resolution of Sickle Cell Leg Ulcers With Voxelotor

NCT05561140 | Terminated Phase 3 Results FDA Drug

• 2 other identifiers: GBT440-042C5341026
• Study Type: interventional
• Target: 88
• Locations: 3 countries
• Sites: 23

Brief Summary

This study is a Phase 3, multicenter, randomized, placebo-controlled study to evaluate the efficacy of voxelotor and standard of care for the treatment of leg ulcers in participants with sickle cell disease. The study is divided into a 5 study periods: Screening, Run-in, Randomized Treatment, Open-label Treatment, and Follow-up/End of Study (EOS). The study will be conducted in approximately 80 eligible participants at approximately 20 global clinical trial sites.

Conditions

Sickle Cell Disease; Leg Ulcers

Keywords

Sickle Cell Disease, SCD

Outcome Measures

Primary Outcomes (1)

• Percentage of Participants Who Achieved Resolution of the Target Ulcers by Week 12 in Randomized Treatment Period

  An ulcer qualified as a target ulcer, if met the following criteria: a) duration of ulcer was greater than equal to (\>=) 2 weeks and less than (\<) 6 months at screening; b) healed by \<25 percent (%) during the SOC run-in phase prior to randomization; c) size was greater than (\>2) square centimeters (cm\^2) at any visit, prior to randomization. Resolution of the target ulcer was defined as skin re-epithelialization confirmed at 2 consecutive study visits, 2 weeks apart during the 12-week randomized treatment period. For participants with more than one target ulcer, all target ulcers must be confirmed resolved in order for the participant to be a responder.

  Through Week 12 of randomized treatment period

Secondary Outcomes (3)

• Time to Resolution of Target Ulcers up to Week 12 in Randomized Treatment Period

  From Day 1 to censoring date before Week 12 or maximum up to Week 12 of randomized treatment period, whichever occurred first

• Change From Baseline in Total Surface Area of Target Ulcers at Week 12 in Randomized Treatment Period

  Baseline, Week 12 of randomized treatment period

• Percentage of Participants With New Ulcers by Week 12 in Randomized Treatment Period

  Through Week 12 of randomized treatment period

Study Arms (2)

Voxeletor + SOC (Standard of Care)

EXPERIMENTAL

Drug: Voxelotor Oral Tablet

Placebo + SOC (Standard of Care)

PLACEBO COMPARATOR

Other: Placebo

Interventions

Voxelotor Oral Tablet DRUG

Synthetic small molecule supplied as 500 mg tablets, administered Orally

Voxeletor + SOC (Standard of Care)

Placebo OTHER

Placebo

Placebo + SOC (Standard of Care)

Eligibility Criteria

• Age: 12 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)

You may qualify if:

• Male or female participants with documented diagnosis of SCD (HbSS, HbS/β0 thalassemia)
• Age 12 years and older
• At least 1 cutaneous ulcer(s) on the lower extremity (leg, ankle, or dorsum of foot) that meets the following criteria:
• Duration: ≥ 2 weeks and \< 6 months at Screening, and
• Size: \> 2 cm2 prior to randomization
• Written informed consent (≥ 18 years) or parental/guardian consent and participant assent (≥ 12-17 years) per IEC policy and requirements, consistent with ICH guidelines

You may not qualify if:

• Target ulcer(s) healed by ≥ 25% during the standard of care run-in period prior to randomization
• Active infection/purulence at ulcer site, or exposed tendon or bone at the ulcer site, based on Investigator's clinical judgment
• Current osteomyelitis at or near the ulcer site
• Known vascular abnormalities that would preclude healing in the opinion of the Investigator (eg, pre-existing severe arterial insufficiency in the affected limb)
• Serum albumin \< 2.0 g/dL
• RBC transfusion within 60 days of initiation of study drug
• Receiving regularly scheduled RBC transfusion therapy (also termed chronic, prophylactic, or preventive transfusion) during the study
• Planned elective surgery within the next 6 months
• Anemia due to bone marrow failure (eg, myelodysplasia)
• Absolute reticulocyte count \< 100 × 109/L
• Screening alanine aminotransferase (ALT) \> 4 × upper limit of normal (ULN)
• Severe renal dysfunction (estimated glomerular filtration rate \[eGFR\] \< 30 mL/min/1.73 m2 by Schwartz formula) or is on chronic dialysis
• Clinically significant bacterial, fungal, parasitic, or viral infection that requires therapy
• Other protocol-defined Eligibility Criteria that apply

Sponsors & Collaborators

• Pfizer: lead

Study Sites (23)

Complexo Hospitalar Universitário Professor Edgard Santos- Universidade Federal Da Bahia

Salvador, Estado de Bahia, 40110-060, Brazil

Location

Universidade Federal Da Bahia Hospital Universitário Professor Edgard Santos

Salvador, Estado de Bahia, 40110-060, Brazil

Location

Hospital São Rafael

Salvador, Estado de Bahia, 41253-190, Brazil

Location

Hospital das Clinicas da Universidade Federal de Minas Gerais

Belo Horizonte, Minas Gerais, 30130-100, Brazil

Location

Multihemo Servicos Medicos S/A

Recife, Pernambuco, 50070-460, Brazil

Location

Hospital das Clínicas da Faculdade de Medicina da Universidade de Sao Paulo

Cerqueira Cesar - Sao Paulo, São Paulo, 05403-000, Brazil

Location

Hospital das Clinicas da Faculdade de Medicina de Ribeirão Preto da Universidade de Sao Paulo

Ribeirão Preto, São Paulo, 14051-140, Brazil

Location

Esho Empresa De Servicos Hospitalares S.A/ Hospital Samaritano Higienopolis

São Paulo, 01232-010, Brazil

Location

Hospital das Clínicas da Faculdade de Medicina da Universidade de Sao Paulo

São Paulo, 01246-000, Brazil

Location

Hospital das Clínicas da Faculdade de Medicina da Universidade de Sao Paulo

São Paulo, 05403-000, Brazil

Location

KEMRI Centre for Clinical Research Butere County Hospital

Butere, Kakamega County, 50100, Kenya

Location

KEMRI Kondele Children's Hospital within Jaramogi Oginga Odinga Teaching and Referral Hospital.

Kisumu, 40100, Kenya

Location

Gertrude's Children's Hospital

Nairobi, 00100, Kenya

Location

KEMRI-Centre for Respiratory Diseases Research-Nairobi

Nairobi, 00100, Kenya

Location

Strathmore University Medical Centre

Nairobi, 00200, Kenya

Location

KEMRI-CRDR, KEMRI Clinical Research Annex

Siaya, 40600, Kenya

Location

SYNLAB

Gwagwalada, Abuja, 902101, Nigeria

Location

University of Calabar Teaching Hospital

Calabar, Cross River State, 540281, Nigeria

Location

SYNLAB

Abuja, Federal Capital Territory, 902101, Nigeria

Location

University of Abuja Teaching Hospital

Gwagwalada, Federal Capital Territory, 902101, Nigeria

Location

Barau Dikko Teaching Hospital/Kaduna State University

Kaduna, 800212, Nigeria

Location

Aminu kano Teaching Hospital

Kano, 700233, Nigeria

Location

Lagos University Teaching Hospital

Lagos, 100254, Nigeria

Location

Related Links

• To obtain contact information for a study center near you, click here.

MeSH Terms

Conditions

Anemia, Sickle Cell; Leg Ulcer

Interventions

voxelotor

Condition Hierarchy (Ancestors)

Anemia, Hemolytic, Congenital; Anemia, Hemolytic; Anemia; Hematologic Diseases; Hemic and Lymphatic Diseases; Hemoglobinopathies; Genetic Diseases, Inborn; Congenital, Hereditary, and Neonatal Diseases and Abnormalities; Skin Ulcer; Skin Diseases; Skin and Connective Tissue Diseases

Results Point of Contact

• Title: Pfizer ClinicalTrials.gov Call Center
• Organization: Pfizer Inc.

ClinicalTrials.gov_Inquiries@pfizer.com

1-800-718-1021

Study Officials

• Pfizer CT.gov Call Center

  Pfizer

  STUDY DIRECTOR

Publication Agreements

• PI is Sponsor Employee: No
• Restriction Type: OTHER
• Restrictive Agreement: Yes

Study Design

• Study Type: interventional
• Phase: phase 3
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: September 27, 2022
• First Posted: September 30, 2022
• Study Start: May 30, 2022
• Primary Completion: June 26, 2024
• Study Completion: October 22, 2024
• Last Updated: July 9, 2025
• Results First Posted: July 9, 2025

Record last verified: 2025-06

Data Sharing

• IPD Sharing: Will share

Locations

KE (6); NG (7); BR (10)