Assessing Physical Function in Sickle Cell Patients Taking Voxelotor

January 29, 2026 updated by: Inova Health Care Services

Assessing Functional Capacity in Sickle Cell Patients Receiving Voxelotor

Voxelotor is a novel hemoglobin polymerization inhibitor which has been demonstrated to reduce hemolysis and improve hemoglobin levels. There have been numerous studies examining the clinical impact of voxelotor in sickle cell disease (SCD) patients, but there are few published reports on the effects of treatment on physical function in patients with SCD. The hypothesis to be tested is that anemic SCD patients will have improvements in performance after 6 months of voxelotor treatment.

Study Overview

Status

Active, not recruiting

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Actual)

6

Phase

  • Phase 2

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United States
    • Virginia
      • Falls Church, Virginia, United States, 22042
        • Inova Schar Cancer Institute

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Study Population

This study will enroll adults diagnosed with various genotypes of sickle cell disease including HbSS, HbSC or HbS beta thalassemia.

Description

Inclusion Criteria:

  1. Provision of signed and dated informed consent form
  2. Stated willingness to comply with all study procedures and availability for the duration of the study
  3. Male or female,
  4. aged 18-65 years
  5. Diagnosis of sickle cell disease with HbSS, HbSc, HbS-beta thalassemia genotypes
  6. Hemoglobin level of 6 g/dL - 10.5 g/dL
  7. Between 0 and 10 vaso-occlusive (VOC) episodes in previous 12 months
  8. Ability to take oral medication and be willing to adhere to the voxelotor regimen
  9. For females of reproductive potential, they will be educated to avoid pregnancy during study period and for one month after due to limited data surrounding pregnancy and voxelotor
  10. For males of reproductive potential: use of condoms or other methods to ensure effective contraception with partner
  11. Agreement to adhere to Lifestyle Considerations (see section 5.3) throughout study duration

Exclusion Criteria:

  1. Hemoglobin results < 6 g/dL or > 10.5 g/dL
  2. Patients receiving hydroxyurea who have had a dose change within the prior 3 months
  3. Females who are breastfeeding or pregnant
  4. Patients who are receiving regularly scheduled blood (RBC) transfusion therapy (also termed chronic, prophylactic, or preventive transfusion) within 30 days of 6MWT
  5. Any form of hepatic dysfunction as demonstrated by alanine aminotransferase (ALT) >4 × ULN or Child-Pugh Class C
  6. Acute kidney injury or chronic renal disease with estimated glomerular filtration rate<30mL/min/1.73 m2
  7. Current or previous diagnosis of malignancy within the last two years excluding local therapy for non-melanoma skin malignancy
  8. Unstable cardiopulmonary disease within the last 6 months prior to study enrollment
  9. Any conditions including behavioral or medical that in the opinion of the investigator, may negatively impact informed consent, participation and study interpretation
  10. Current use of commercially available voxelotor
  11. Prior hypersensitivity to voxelotor or its excipients
  12. Patients with baseline gait and other physical impairments that would limit 6MWT and other functional assessment at discretion of the investigator
  13. Patients who on day of assessment present with vaso-occlusive crisis or rate their pain greater than 6 on a scale of 1-10 using the Numeric Rating Scale will not be assessed that day and re-screened at the investigator's discretion.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: N/A
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Voxeletor
Drug: Voxelotor
Voxelotor is administered orally at a dose of 1500mg daily.
Other Names:
  • Oxbryta

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Participant's Physical Performance Using 6 Minutes Walk Test (6MWT) Pre and Post Treatment with Voxelotor.
Time Frame: 6 months from the treatment initiation
The 6MWT is a sensitive objective assessment of functional exercise capacity which assess distance walked over 6 minutes.This test detects minor and moderate functional impairment resulting from treatment with Voxelotor.
6 months from the treatment initiation

Other Outcome Measures

Outcome Measure
Measure Description
Time Frame
The Change in the Quality of Life as assessed by Sheehan Disability Scale (SDS) During the 6 Months Trial Period.
Time Frame: 6 months from the treatment initiation
The SDS is a short self-reporting questionnaire that assess functional impairment in work/school, social and family life. The assessment scale has a total score of 30 (0 unimpaired and 30 extremely impaired).
6 months from the treatment initiation

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Inova Health Care Services

Collaborators

Pfizer

Investigators

  • Principal Investigator: Sheinei Alan, Inova Schar Cancer Institute

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

October 23, 2023

Primary Completion (Actual)

September 17, 2025

Study Completion (Estimated)

June 15, 2026

Study Registration Dates

First Submitted

August 7, 2023

First Submitted That Met QC Criteria

September 1, 2023

First Posted (Actual)

September 5, 2023

Study Record Updates

Last Update Posted (Actual)

February 2, 2026

Last Update Submitted That Met QC Criteria

January 29, 2026

Last Verified

January 1, 2026

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • U23-02-4988

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

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

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Sickle Cell Disease

Clinical Trials on Voxelotor

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Argentina

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Subscribe