Hydroxyurea for secondary stroke prevention in children with sickle cell anemia in Nigeria: a randomized controlled trial.

We tested the hypothesis that fixed oral moderate-dose hydroxyurea (20 mg/kg per day) for initial treatment of secondary stroke prevention results in an 80% relative risk reduction of stroke or death when compared with fixed oral low-dose hydroxyurea (10 mg/kg per day) in a phase 3 double-blind, parallel-group, randomized controlled trial in children with sickle cell anemia (SCA) living in Nigeria. A total of 101 participants were randomly allocated to low-dose (n = 49) and moderate-dose (n = 52) hydroxyurea treatment groups. The median participant follow-up was 1.6 years (interquartile range, 1.0-2.3), with a planned minimum follow-up of 3.0 years. A total of 6 recurrent strokes and 2 deaths vs 5 recurrent strokes and 3 deaths occurred in the low- and moderate-dose groups, respectively. The incidence rate ratio (IRR) of the primary outcome measure of stroke or death in the low- and moderate-dose hydroxyurea treatment groups was 0.98 (95% confidence interval [CI], 0.32-3.00; P = .97). The trial was stopped early owing to no clinical difference in the incidence rates of the primary outcome measure. The incidence rates of recurrent strokes were 7.1 and 6.0 per 100 person-years in the low- and moderate-dose groups, respectively, (IRR, 1.18; 95% CI, 0.30-4.88; P = .74). As a measure of adherence to the oral hydroxyurea therapy, the median percent of returned pills was 3.0% and 2.6% in the low- and moderate-dose groups, respectively. No participant had hydroxyurea therapy stopped for myelosuppression. For children with SCA in low-income settings without access to regular blood transfusion therapy, initial low-dose hydroxyurea is a minimum known efficacious dose for secondary stroke prevention.

A Novel Newborn Screening Program for Sickle Cell Disease in Nigeria.

Newborn screening for sickle cell disease (SCD) is sparse in sub-Saharan Africa. The leadership of the Aminu Kano Teaching Hospital (AKTH) in Kano, Nigeria, with the support of local religious authorities, established a groundbreaking SCD newborn screening program that has become the standard of care for pregnant women and their newborns. Our program includes (1) prenatal genetic counseling for all pregnant women in the antenatal clinic, (2) newborn screening, (3) postnatal genetic counseling for parents of newborns diagnosed with SCD and SCT, and (4) referral of newborns with SCD for follow-up in the SCD Comprehensive Care Clinic by 3 months of age. From September 2020 to December 2023, the team screened 7530 infants for SCD at the AKTH, identifying 126 (1.7%) infants with SCD and 1546 (20.5%) with SCT. Of these, 93 (73.8%) newborns with SCD received individualized genetic counseling, and 43 (46%) were referred to the SCD Comprehensive Care Clinic before 3 months. Group genetic counseling was provided to the parents of 778 (50.3%) of newborns identified with SCT. The SCD newborn screening at the AKTH is now standard care, indicating the viability of sustaining an SCD newborn screening program that provides pre- and postnatal genetic counseling and comprehensive SCD care within a low-income setting.

Capacity Building for Primary Stroke Prevention Teams in Children Living With Sickle Cell Anemia in Africa.

BACKGROUND: Nigeria has the highest proportion of children with sickle cell anemia (SCA) globally; an estimated 150,000 infants with SCA are born annually. Primary stroke prevention in children with SCA must include Nigeria. We describe capacity-building strategies in conjunction with two National Institutes of Health-funded primary stroke prevention trials (a feasibility trial and phase III randomized controlled trial) with initial hydroxyurea treatment for children with SCA and abnormal transcranial Doppler (TCD) velocities in Nigeria. We anticipated challenges to conducting clinical trials in a low-resource setting with a local team that had not previously been involved in clinical research and sought a sustainable strategy for primary stroke prevention. METHODS: This is a descriptive, prospective study of challenges, solutions, and research teams in two trials that enrolled a total of 679 children with SCA. RESULTS: As part of the capacity-building component of the trials, over eight years, 23 research personnel (physicians, nurses, research coordinators, a statistician, and a pharmacist) completed a one-month research governance and ethics training program at Vanderbilt University Medical Center, USA. A lead research coordinator for each site completed the Society of Clinical Research Professionals certification. TCD machines were donated; radiologists and nonradiologists were trained and certified to perform TCD. A scalable E-prescription was implemented to track hydroxyurea treatment. We worked with regional government officials to support ongoing TCD-based screening and funding for hydroxyurea for children with SCA at a high risk of stroke. CONCLUSIONS: Our trials and capacity building demonstrate a sustainable strategy to initiate and maintain pediatric SCA primary stroke prevention programs in Africa.