A Phase 2/3 Study in Adult and Adolescent Participants With SCD
A Phase 2/3 Randomized, Multicenter Study of Osivelotor Administered Orally to Adult and Adolescent Participants With Sickle Cell Disease
3 other identifiers
interventional
389
6 countries
49
Brief Summary
The purpose of this study is to evaluate the safety, tolerability, efficacy, pharmacokinetics and pharmacodynamics of osivelotor.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P75+ for phase_2
Started Sep 2022
Longer than P75 for phase_2
49 active sites
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
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Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
June 21, 2022
CompletedFirst Posted
Study publicly available on registry
June 24, 2022
CompletedStudy Start
First participant enrolled
September 22, 2022
CompletedPrimary Completion
Last participant's last visit for primary outcome
December 30, 2030
ExpectedStudy Completion
Last participant's last visit for all outcomes
December 31, 2032
March 20, 2026
March 1, 2026
8.3 years
June 21, 2022
March 19, 2026
Conditions
Outcome Measures
Primary Outcomes (3)
Part A
Number of adult participants with change from baseline in hemoglobin (Hb) through week 12 as measured by change in osivelotor concentrations from baseline or percentage change from baseline of clinical measures of anemia Hb and hemolysis (including indirect bilirubin, reticulocytes and lactate dehydrogenase).
Through week 12
Part B
Co-primary endpoints: Hb response (increase from baseline of \>1 g/dL) at Week 48 (based on average of Hb levels at Week 40 and Week 48) and the Annualized rate of VOC through end of Week 48. A VOC is defined as an acute episode of pain that: * Has no medically determined cause other than a vaso-occlusive event, and * Results in a visit to a medical facility (hospitalization, emergency department, urgent care center, outpatient clinic, or infusion center), and * Requires parenteral narcotic agents, parenteral nonsteroidal anti-inflammatory drugs (NSAIDs), or an increase in treatment with oral narcotics. Complicated VOCs of acute chest syndrome (ACS), hepatic sequestration, splenic sequestration, priapism, and dactylitis that meet the requirements listed above will be included in this co-primary endpoint.
Through week 48
OLE
Incidence of Treatment Emergent Adverse Events: * Incidence of SAEs * Incidence of AEs leading to discontinuation * Change from baseline in laboratory parameters.
Approximately 24 months after last patient enrolled
Study Arms (3)
Part A
ACTIVE COMPARATORInitially, participants will be randomized 1:1 to 100 mg and 150 mg daily. Upon review of the 150 mg safety data from at least 6 participants, there will be 1:1:1 randomization: 100 mg, 150 mg, and up to 200 mg. Participants will then receive maintenance once daily doses through Week 12.
Part B
PLACEBO COMPARATORStudy drug arm: Adult participants will receive osivelotor at 300 mg QD loading dose for 7 days followed by 150 mg QD through Week 48. Adolescent participant dose will be defined in a future protocol amendment. Placebo arm: Participants will receive placebo tablets for 48 weeks.
OLE
EXPERIMENTALAdult Participants will receive 150 mg open-label osivelotor up to 2 years after the last participant's visit in Part B or when the drug is commercially available in that region. The appropriate doses for adolescents will be defined in a future protocol amendment.
Interventions
Tablets which contain drug substance
Eligibility Criteria
You may qualify if:
- Part A, Part B, and OLE:
- Male or female with SCD
- Participants with stable Hb value as judged by the Investigator
- For participants taking hydroxyurea and/or L-glutamine, the dose must be stable for at least 90 days prior to signing the ICF or assent and with no anticipated need for dose adjustments during the study in the opinion of the Investigator.
- Part B:
- Participants with SCD ages 12 to 65 years, inclusive
- Participants with more than or equal to 2 and ≤ 10 VOCs within 12 months of Screening.
- OLE:
- \- Participants who have completed the Part B will be eligible.
You may not qualify if:
- Part A, Part B, and OLE:
- Participants who had more than 10 VOC within 12 months of screening
- Female participant who is breastfeeding or pregnant
- Participants who receive RBC transfusion therapy regularly or received an RBC transfusion ---for any reason within 90 days of Day 1
- Participants hospitalized for sickle cell crisis or other vaso-occlusive event within 14 days of signing the ICF or anytime during the screening period.
Contact the study team to confirm eligibility.
Sponsors & Collaborators
- Pfizerlead
Study Sites (49)
Smilow Cancer Hospital
New Haven, Connecticut, 06511, United States
Edward Jenner Research Group Center LLC
Plantation, Florida, 33317, United States
Pediatric Hematology / Oncology a division of Kidz Medical services
West Palm Beach, Florida, 33407, United States
St. Mary's Medical Center
West Palm Beach, Florida, 33407, United States
Alpha Clinical Research Georgia
Dunwoody, Georgia, 30350, United States
Sonar Clinical Research
Riverdale, Georgia, 30274, United States
University of Illinois at Chicago Clinical Research Center
Chicago, Illinois, 60612, United States
University of Illinois Hospital and Health Sciences System - Investigational Drug Services (IDS)
Chicago, Illinois, 60612, United States
University of Illinois Hospital and Health Sciences System
Chicago, Illinois, 60612, United States
LSU Health Baton Rouge-North Clinic
Baton Rouge, Louisiana, 70805, United States
Our Lady of the Lake Hospital, Inc.
Baton Rouge, Louisiana, 70808, United States
Our lady of the Lake Hospital
Baton Rouge, Louisiana, 70808, United States
University Medical Center New Orleans
New Orleans, Louisiana, 70112, United States
Mississippi Center for Advanced Medicine
Madison, Mississippi, 39110, United States
University Health
Kansas City, Missouri, 64108, United States
Clinical & Translational Research Center (CTRC)
Chapel Hill, North Carolina, 27514, United States
UNC Health
Chapel Hill, North Carolina, 27514, United States
UNC Eastowne Medical Office Building - Consent Only
Chapel Hill, North Carolina, 27517, United States
UNC IDS
Morrisville, North Carolina, 27560, United States
McGovern Medical School at UTHealth
Houston, Texas, 77030, United States
Memorial Hermann Hospital, Texas Medical Center - Clinical Research Unit (CRU)
Houston, Texas, 77030, United States
The University of Texas Health Science Center at Houston
Houston, Texas, 77030, United States
UT Physicians Comprehensive Sickle Cell Clinic
Houston, Texas, 77030, United States
Inova Schar Cancer Institute
Fairfax, Virginia, 22031, United States
Hospital Universitario Professor Edgar Santos
Salvador, Estado de Bahia, 40110-060, Brazil
Multihemo Servicos Medicos S/A
Recife, Pernambuco, 50070-460, Brazil
Hospital Das Clinicas da Faculdade de Medicina de Ribeirão Preto - USP
Ribeirão Preto, São Paulo, 14051-140, Brazil
Fundacao Faculdade Regional de Medicina de Sao Jose do Rio Preto
São José do Rio Preto, São Paulo, 15090-000, Brazil
BP A Beneficência Portuguesa de São Paulo
São Paulo, São Paulo, 01321 001, Brazil
BP - A Beneficência Portuguesa de São Paulo
São Paulo, São Paulo, 01323-900, Brazil
Casa de Saude Santa Marcelina
São Paulo, São Paulo, 08270-070, Brazil
Casa de Saude Santa Marcelina
São Paulo, São Paulo, 08270-120, Brazil
Esho Empresa de Servicos Hospitalares S A
São Paulo, SÃO Paulo- Brasil, 01232-011, Brazil
Instituto Estadual de Hematologia Arthur Siqueira Cavalcanti - HEMORIO
Rio de Janeiro, 20211-030, Brazil
Esho Empresa de Servicos Hospitalares S A
São Paulo, 01232-010, Brazil
Real e Benemerita Associacao Portuguesa de Sao Paulo
São Paulo, 01321-001, Brazil
Hospital das Clinicas da Faculdade de Medicina da Universidade de Sao Paulo
São Paulo, 05403-000, Brazil
Hospital das Clinicas da Faculdade de Medicina da Universidade de Sao Paulo
São Paulo, 05403-010, Brazil
Nirmal Hospital Pvt Ltd
Surat, Gujarat, 395002, India
Chopda Medicare & Research Centre Pvt. Ltd: Magnum Heart Institute
Nashik, Maharashtra, 422005, India
KEMRI/CRDR, Siaya, KEMRI Clinical Research Annex
Kisumu, Siaya County, 40600, Kenya
Gertrude's Children's Hospital
Nairobi, 00100, Kenya
Kenya Medical Research Institute - Centre for Respiratory Disease Research
Nairobi, 00100, Kenya
Center for Research In Therapeutic Sciences (CREATES), Strathmore University Medical Centre
Nairobi, 00200, Kenya
University College Hospital Ibadan
Ibadan, Oyo/ibadan North, 200212, Nigeria
Aminu Kano Teaching Hospital
Kano, 700233, Nigeria
Lagos University Teaching Hospital
Lagos, 100254, Nigeria
University Hospitals Bristol and Weston NHS Foundation Trust
Bristol, BS2 8ED, United Kingdom
Bristol Royal Infirmary
Bristol, BS2 8EX, United Kingdom
Related Publications (2)
Li Z, Alt C, Dufu K, Hutchaleelaha A, Xu Q, Zhang X, Li CM, Rademacher P, Bosmajian C, Pochron MP, Partridge JR, Oksenberg D, Cathers BE. Discovery of Osivelotor (GBT021601): A Potent, Next-Generation Sickle Hemoglobin Polymerization Inhibitor. ACS Med Chem Lett. 2025 Jul 8;16(8):1526-1532. doi: 10.1021/acsmedchemlett.5c00076. eCollection 2025 Aug 14.
PMID: 40832524DERIVEDObadina M, Wilson S, Derebail VK, Little J. Emerging Therapies and Advances in Sickle Cell Disease with a Focus on Renal Manifestations. Kidney360. 2023 Jul 1;4(7):997-1005. doi: 10.34067/KID.0000000000000162. Epub 2023 May 31.
PMID: 37254256DERIVED
Related Links
MeSH Terms
Conditions
Condition Hierarchy (Ancestors)
Study Officials
- STUDY DIRECTOR
Pfizer CT.gov Call Center
Pfizer
Central Study Contacts
Study Design
- Study Type
- interventional
- Phase
- phase 2
- Allocation
- RANDOMIZED
- Masking
- QUADRUPLE
- Who Masked
- PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
- Masking Details
- Part B only
- Purpose
- TREATMENT
- Intervention Model
- PARALLEL
- Sponsor Type
- INDUSTRY
- Responsible Party
- SPONSOR
Study Record Dates
First Submitted
June 21, 2022
First Posted
June 24, 2022
Study Start
September 22, 2022
Primary Completion (Estimated)
December 30, 2030
Study Completion (Estimated)
December 31, 2032
Last Updated
March 20, 2026
Record last verified: 2026-03
Data Sharing
- IPD Sharing
- Will share
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.