Gender
All
Age Group
16 Years and up
Accepting Healthy Volunteers
No
Inclusion Criteria:
- Age 16 years or older (18 years or older [France and Germany]); participants age 16
or 17 years must physically have completed puberty;
- Documented diagnosis of sickle cell disease (SCD) (HbSS, HbSC [combined
heterozygosity for hemoglobins S and C], HbS/beta 0- thalassemia, HbS/ beta plus
thalassemia, or other sickle cell syndrome variants);
- At least 2 SCPCs and no more than 10 SCPCs in the past 12 months;
- Hemoglobin at least 5.5 and 10.5 gram per deciliter (g/dL) at the most. Hemoglobin
concentration must be based on an average of at least 2 Hb concentration
measurements (separated by ≥7 days) collected during the Screening Period;
- If taking hydroxyurea, the hydroxyurea dose must be stable for at least 90 days
before starting study drug. Discontinuation of hydroxyurea requires a 90-day washout
prior to informed assent/consent;
- Women capable of becoming pregnant must agree to use 2 forms of contraception.
Exclusion Criteria:
- Pregnant, breastfeeding, or parturient;
- Receiving regularly scheduled transfusions;
- Hepatobiliary disorders including but not limited to significant liver disease or
gallbladder disease;
- Severe kidney disease;
- Prior exposure to gene therapy or prior bone marrow or stem cell transplantation;
- Currently receiving treatment with a disease-modifying therapy for SCD (eg,
voxelotor, crizanlizumab, L-glutamine), with the exception of hydroxyurea. The last
dose of voxelotor, crizanlizumab, and L-glutamine must have been administered at
least 90 days before randomization;
- Currently receiving treatment with hematopoietic stimulating agents; the last dose
must have been administered at least 90 days before starting study drug;
- Received treatment on another investigational trial within 90 days prior to start of
study drug or plans to participate in another investigational drug trial;
- Taking medications that are strong inhibitors of CYP3A4/5 or strong inducers of
CYP3A4 that cannot be stopped in an acceptable timeframe before starting study drug
(timeframe will be discussed with your doctor).