The Effect of Voxelotor on Exercise Capacity of Youths With Sickle Cell Anemia

About the study

This study is a pilot, open-label, single-arm study to evaluate the effect of the sickle cell medication voxelotor on exercise capacity, as measured by cardiopulmonary exercise testing (CPET) in patients 12 years of age and older with sickle cell anemia (SCA).

Study point of contact

Vivian Phan, MS
Elizabeth Yang, MD, PhD


1 United States site


> 12 Years


Phase 4

Study type








participation requirements

Provision of signed and dated informed consent form
Stated willingness to comply with all study procedures and availability for the duration of the study
Male or female, age > 12 years
In good general health as evidenced by medical history and diagnosed with a genetically severe form of sickle cell anemia (Hgb SS, Hgb S beta 0 thalassemia, Hgb SCHarlem, and others)
Patients who are on Hydroxyurea need to be on a stable dose for at least 3 months without anticipated change in dosing until the study is completed.
Ability to take oral medication and willingness to adhere to daily voxelotor and 2 CPETs at scheduled intervals.
For females of reproductive potential who are sexually active: use of highly effective contraception for at least 1 month prior to screening and agreement to use such a method during study participation and for an additional 30 days after the end of study.
For males of reproductive potential: use of condoms or other methods to ensure effective contraception with partner

participation restrictions

Patients on chronic transfusions or who received a transfusion within last 8 weeks
Patients who had hospitalization for vaso-occlusive crisis or acute chest syndrome within 30 days prior to informed consent/assent.
Patients who have screening alanine aminotransferase (ALT) > 4X upper limit of normal
Patients who suffer from physical inactivity attributable to clinically significant musculoskeletal, cardiovascular, or respiratory comorbidities
Patients already taking commercially available voxelotor
Prior hypersensitivity to voxelotor or excipients.
Pregnant patients


  • Fairfax, Virginia, United States, Pediatric Specialist of Virginia, 22031 [Recruiting]
Last updated 2020-10-08