Inclusion Criteria

1. Documented diagnosis of sickle cell disease of any genotype confirmed by laboratory testing during screening

2. Ineligible or unable to participate in actively recruiting clinical studies of voxelotor

3. Hemoglobin (Hb) ≤ 10.5 g/dL during screening

4. No alternative treatment options in the judgment of the treating investigator

5. Participants, who if female and of child bearing potential, agree to use highly effective methods of contraception from study start to 30 days after the last dose of voxelotor, and who if male, agree to use barrier methods of contraception from study start to 30 days after the last dose of voxelotor

6. Patient has provided documented informed consent (the informed consent form [ICF] must be reviewed and signed by each participant),or for participants under 18 years of age, signed parental/legal guardian consent and participant assent.

Exclusion Criteria

1. Female who is breast feeding or pregnant

2. Hepatic dysfunction characterized by alanine aminotransferase (ALT) >4 × ULN

3. Patients with clinically significant bacterial, fungal, parasitic, or viral infection which require therapy: - Patients with acute bacterial infection requiring antibiotic use should delay screening/enrollment until the course of antibiotic therapy has been completed. - Patients with known active hepatitis A, B, or C or who are known to be human immunodeficiency virus (HIV) positive

4. Renal dialysis

5. Non-SCD conditions or complications of SCD for which survival beyond 3 months is unlikely, in the opinion of the treating Investigator

6. Any condition affecting drug absorption, such as major surgery involving the stomach or small intestine (prior cholecystectomy is acceptable)

7. Participated in another clinical trial of an investigational agent (or medical device) within 30 days or 5 half-lives of date of informed consent, whichever is longer, or is currently participating in another trial of an investigational agent (or medical device)

8. Medical, psychological, or behavioral conditions, which, in the opinion of the Investigator, may preclude safe participation, interfere with compliance or preclude informed consent

The Sponsor Medical Monitor makes the sole and final enrollment determination for any
patient.