A Phase 3 interventional study of Crizanlizumab and Placebo in Sickle Cell Disease, sponsored by Novartis Pharmaceuticals. Recruiting at 35 sites in 5 countries. Open to participants aged 12 Years to 100 Years. Per ClinicalTrials.gov, last updated 2026-09-15.
Sponsored by Novartis Pharmaceuticals · Phase 3, Interventional, and Treatment
A phase III, multi-center, randomized, placebo-controlled, double-blind study to assess efficacy and safety of crizanlizumab (5 mg/kg) versus placebo, with or without hydroxyurea/hydroxycarbamide therapy, in adolescent and adult Sickle Cell Disease patients with frequent vaso-occlusive crises.
Study CSEG101A2303 (SPARKLE) is a Phase III, multicenter, randomized, double-blind study to assess efficacy and safety of crizanlizumab 5 mg/kg versus placebo, with or without hydroxyurea/ hydroxycarbamide therapy (HU/HC), in Sickle Cell Disease patients aged 12 years and older with frequent vaso-occlusive crises (4-12 events in 12 months prior to the screening visit).
Participants will be randomized in a 2:1 ratio to the crizanlizumab 5 mg/kg or placebo treatment arm. Central randomization will be stratified by concomitant HU/HC usage (yes/no) and region (South America, North America, and sub-Saharan Africa) at baseline.
Key Inclusion Criteria:
Participants who have not been receiving HU/HC, and/or erythropoietin stimulating agent must not have received it for at least 6 months prior to screening visit.
Key Exclusion Criteria:
Participants receive Crizanlizumab (SEG101) at 5.0 mg/kg and standard of care.
Biological: Crizanlizumab
Participants receive the placebo drug and standard of care.
Drug: Placebo
Crizanlizumab is supplied in single use 10 mL glass vials at a concentration of 10 mg/mL. One vial contains 100 mg of crizanlizumab. This is a concentrate for solution for IV infusion.
Also known as: SEG101, Adakveo®, Ryverna®
Placebo is supplied in single use 10 mL glass vials at a concentration of 0 mg/mL. This is a concentrate for solution for IV infusion.
Annualized rate of VOCs that are healthcare professional (HCP)-managed (including VOCs leading to management at a health care facility or those managed via remote consultation) in each treatment arm
Vaso oclusive crisis (VOC) is defined as a pain crisis (acute onset of pain for which there is no other medically determined explanation other than vaso-occlusion) lasting for at least 4 hours which is treated as per local guidelines with standard of care therapy used to treat VOC. Acute chest syndrome (ACS), priapism and hepatic or splenic sequestration will be considered VOC in this study. VOCs included are those HCP-managed in a healthcare facility and HCP-managed via remote consultation. Annualized rate of VOC events = (Number of VOC events \* 365)/(number of days in the observation period). Observation period = time from date of randomization to minimum of (last dose date until treatment discontinuation + 27 days, date of initiation or discontinuation of HU/HC or L-Glutamine (or other therapies such as Voxelotor and erythropoietin therapies to treat SCD and/or to prevent/reduce VOCs), date of randomization + 365 days).
Time frame: 1 year
The annualized rate of all VOCs including VOCs that are HCP-managed (either at a health care facility or via remote consultation) as well as those that are self-managed without recommendations from HCP during the event in each treatment arm
VOCs can be categorized as those HCP-managed in a healthcare facility, HCP-managed via remote consultation, or self-managed without recommendations from HCP during the event. Annualized rate of VOC events = (Number of VOC events \* 365)/(number of days in the observation period). To capture VOC events that are self-managed, and in order to avoid VOC recall bias and to make sure the pain events are captured in real-time, a cloud-based application will be used and setup an account for each participant.
Time frame: 1 year
Annualized rate of VOC by subtype of management in each treatment arm over the planned 52-week period.
Vaso oclusive crisis (VOC) is defined as a pain crisis lasting for at least 4 hours which is treated as per local guidelines with standard of care therapy. Acute chest syndrome (ACS), priapism and hepatic or splenic sequestration will be considered VOC in this study. VOCs can be categorized as those HCP-managed in a healthcare facility, HCP-managed via remote consultation, or self-managed without recommendations from HCP during the event. Annualized rate of VOC is the number of VOC events during a year period.
Time frame: 1 year
The time to first VOC that is HCP-managed (including VOCs leading to management at a health care facility or those managed via remote consultation) between treatment arms.
VOC is defined as a pain crisis lasting for at least 4 hours which is treated as per local guidelines with standard of care therapy. ACS, priapism and hepatic or splenic sequestration will be considered VOC in this study. VOCs included are those HCP-managed in a healthcare facility and HCP-managed via remote consultation. Time to first occurrence of VOC that is HCP-managed (either at a health care facility or via remote consultation) is defined as the time from the date of randomization to the date of the first occurrence of the VOC.
Time frame: 1 year
Proportion of participants free from VOCs that are HCP-managed (including VOCs leading to management at a health care facility or those managed via remote consultation) in each treatment arm over the planned 52-week treatment period.
To assess the number of participants free from VOCs leading to healthcare visit. VOC is defined as a pain crisis lasting for at least 4 hours which is treated as per local guidelines with standard of care therapy. ACS, priapism and hepatic or splenic sequestration will be considered VOC in this study. A participant is free from VOC if they do not have a VOC crisis.
Time frame: 1 year
Duration of VOCs that are HCP-managed (including VOCs leading to management at a health care facility or those managed via remote consultation) in each treatment arm over the planned 52-week treatment period.
VOC is defined as a pain crisis lasting for at least 4 hours which is treated as per local guidelines with standard of care therapy. ACS, priapism and hepatic or splenic sequestration will be considered VOC in this study. Duration of HCP-managed VOC is defined as end date of the VOC - start date of the VOC + 1 day.
Time frame: 1 year
Number of participants with anti-SEG101 (crizanlizumab) antibodies (any time)
Immunogenicity: measurement of anti-drug antibodies (ADA) to crizanlizumab.
Time frame: 2 years
Incidence and severity of Adverse Events (AEs) and Serious Adverse Events (SAEs)
Incidence and severity of AEs and SAEs by treatment group, including changes in vital signs, electrocardiograms (ECGs), and laboratory results qualifying and reported as AEs.
Time frame: 2 years
Absolute change from baseline in hemoglobin
Assessment of safety of SEG101
Time frame: Baseline, 2 years
Plan to share: Yes — Novartis is committed to sharing with qualified external researchers, access to patient-level data and supporting clinical documents from eligible studies. These requests are reviewed and approved by an independent review panel on the basis of scientific merit. All data provided is anonymized to respect the privacy of patients who have participated in the trial in line with applicable laws and regulations. This trial data availability is according to the criteria and process described on www.clinicalstudydatarequest.com
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