A Study Evaluating the Safety, Pharmacokinetics, Pharmacodynamics and Efficacy of Crovalimab for the Management of Acute Uncomplicated Vaso-Occlusive Episodes (VOE) in Participants With Sickle Cell Disease (SCD).

Prior treatment

• More than 10 VOEs within the last 12 months prior to presentation, that have required a medical facility visit.
• Major surgery and/or hospitalization for any reason within 30 days.
• History of Neisseria meningitidis infection within 6 months prior.
• Immunized with a live attenuated vaccine within 30 days.
• Pregnant or breastfeeding, or intending to become pregnant during the study or within 322 days (approximately 10.5 months) after the study drug administration.
• Participation in another interventional treatment study with an investigational agent or use of any experimental therapy within the prior 28 days or within five half-lives of that investigational product, whichever was greater.

Other illness

• Evidence or high suspicion of a severe systemic infection.
• History of hematopoietic stem cell transplant.

Lab values

• Known HIV infection with a documented CD4 count \<200 cells/µL.

Other

• Pain related to the current VOE ongoing for \>36 hours.
• Acute pain related to avascular necrosis, hepatic or splenic sequestration, or priapism.
• Pain atypical of an acute uncomplicated VOE.
• Evidence of or suspicion of ACS.
• Transfusion or receipt of blood products within 3 months or current participation in a chronic transfusion protocol.
• Known or suspected hereditary complement deficiency.

• Body weight \>=40 kg.
• Confirmed diagnosis of HbSS (SCD genotype of sickle cell anemia) or HbSβ0 (SCD genotype of sickle cell beta zero thalassemia).
• Vaccination against Neisseria Meningitidis serotypes A, C, W, and Y.
• Vaccinations against H. influenzae type B and S. pneumoniae.
• Participants vaccinated against SARS-CoV-2 are eligible, as long as it has been 3 days or more after inoculation with the vaccine.
• Diagnosis of an acute uncomplicated VOE, that requires admission to a hospital/acute medical facility and treatment with parenteral opioid analgesics.
• Adequate hepatic and renal function.
• Hemoglobin \>=5 grams/deciliter (g/dL)
• Platelet count \>=100,000/microliter (µL)
• Participants receiving SCD-directed therapies must be on a stable dose for \>=28 days.
• For female participants of childbearing potential, an agreement to remain abstinent or use contraception for 322 days (approximately 10.5 months) after the dose of study treatment.