Hydroxyurea (HU) also known as hydroxycarbamide, is an oral antineoplastic drug and an inhibitor of ribonucleotide reductase that has shown to have many beneficial effects for treating sickle cell disease (SCD). These effects include increasing foetal haemoglobin (HbF) concentration in RBCs, improving metabolism of nitric oxide, and reducing red cell-endothelial interaction and erythrocyte density. These disease-modifying effects have been shown to decrease episodes of pain, acute chest syndrome, hospital admissions and the need for transfusions. In high-income countries, HU is the first line primary disease modifying therapy for patients with SCD regardless of clinical severity. Its efficacy and effectiveness in children and adults with SCD have also been shown in low resources settings.
The availability of hydroxyurea is still limited in low- and middle-income countries, particularly in Sub Saharan Africa, where 50-90% of children with SCD still die before the age of 5 years because interventions to manage and treat SCD, including treatment with hydroxyurea, are not currently provided as a standard of care or are mostly inaccessible to patients.
Following the resolution at the Sixty-ninth World Health Assembly on promoting innovation and access to quality, safe, efficacious, and affordable medicines for children, WHO and partners in the Global Accelerator for Paediatric Formulations Network (GAP-f) have increased their efforts to deliver on this global commitment and have scaled up activities to ensure that age-appropriate formulations are available for children.
On 8 to 10 September 2025, WHO convened the first ever Paediatric Drug Optimization process for SCD and gathered a group, consisting of scientific, clinical, and public health experts from diverse geographic regions to identify priorities for research and development in SCD treatment as well as to develop a target product profile (TPP) for hydroxyurea and provide clear guidance for manufacturers committed to contribute to global access to SCD treatment.
The World Health Organization is now seeking feedback on hydroxyurea draft TPPs from industry experts, product developers, the scientific community, implementers, clinicians, and health programme personnel currently involved in the management of infectious diseases.
TPP on hydroxyurea