Feasibility trial for primary stroke prevention in children with sickle cell anemia in Nigeria (SPIN trial).

The vast majority of children with sickle cell anemia (SCA) live in Africa, where evidence-based guidelines for primary stroke prevention are lacking. In Kano, Nigeria, we conducted a feasibility trial to determine the acceptability of hydroxyurea therapy for primary stroke prevention in children with abnormal transcranial Doppler (TCD) measurements. Children with SCA and abnormal non-imaging TCD measurements (≥200 cm/s) received moderate fixed-dose hydroxyurea therapy (∼20 mg/kg/day). A comparison group of children with TCD measurements <200 cm/s was followed prospectively. Approximately 88% (330 of 375) of families agreed to be screened, while 87% (29 of 33) of those with abnormal TCD measurements, enrolled in the trial. No participant elected to withdraw from the trial. The average mean corpuscular volume increased from 85.7 fl at baseline to 95.5 fl at 24 months (not all of the children who crossed over had a 24 month visit), demonstrating adherence to hydroxyurea. The comparison group consisted of initially 210 children, of which four developed abnormal TCD measurements, and were started on hydroxyurea. None of the monthly research visits were missed (n = total 603 visits). Two and 10 deaths occurred in the treatment and comparison groups, with mortality rates of 2.69 and 1.81 per 100 patient-years, respectively (P = .67). Our results provide strong evidence, for high family recruitment, retention, and adherence rates, to undertake the first randomized controlled trial with hydroxyurea therapy for primary stroke prevention in children with SCA living in Africa.

Primary stroke prevention in Nigerian children with sickle cell disease (SPIN): challenges of conducting a feasibility trial.

BACKGROUND: The majority of children with sickle cell disease (SCD), approximately 75%, are born in sub-Saharan Africa. For children with elevated transcranial Doppler (TCD) velocity, regular blood transfusion therapy for primary stroke prevention is standard care in high income countries, but is not feasible in sub-Saharan Africa. PROCEDURE: In the first U.S. National Institute of Health (NIH) sponsored SCD clinical trial in sub-Saharan Africa, we describe the protocol and challenges unique to starting a clinical trial in this region. We are conducting a single arm pilot trial of hydroxyurea therapy in children with TCD velocity ≥200 cm/sec in the middle cerebral arteries. Eligible children will be placed on hydroxyurea (n = 40) and followed for 3 years at Aminu Kano Teaching Hospital, Nigeria. Adherence will be measured via the Morisky Scale and adverse events will be determined based on hospitalization. RESULTS: Originally, a randomized placebo trial was planned; however, placebo was not approved by the local Ethics Committee. Hence a single arm trial of hydroxyurea will be conducted and five controls per patient with normal TCD measurements will be followed to compare the rate of adverse events to those with abnormal TCD measurements taking hydroxyurea. Using non-NIH funding, over 9 months, multiple face-to-face investigator meetings were conducted to facilitate training. CONCLUSION: A hydroxyurea trial (NCT01801423) for children with SCD is feasible in sub-Saharan Africa; however, extensive training and resources are needed to build a global patient oriented multi-disciplinary research team with a common purpose.