Not Yet RecruitingNot Applicable

Hydroxyurea Optimisation in Sickle Cell Disease

Nigeria100 participantsStarted 2026-05-08

Plain-language summary

The wide interindividual variability in clinical response to hydroxyurea therapy in the management of sickle cell disease has limited its use. These variabilities have been linked to differences in pharmacodynamics, pharmacokinetics, and pharmacogenetics. This study, therefore, aims to enhance understanding of these factors as they relate to hydroxyurea therapy, with the overall goal of developing a precision medicine algorithm. The study will be a prospective cohort pharmacokinetic study of 100 Nigerian patients with sickle cell disease, including current hydroxyurea users and naive patients. Pharmacodynamic markers will be collected to evaluate response. PopPK and PK-PD models will be developed in Monolix, exposure-response relationships will be analysed in R, and pregnancy, lactation, and paediatrics PBPK models will be developed in Simcyp or PK-SIM to inform dose optimisation. This study aims to build a pharmacometric model by integrating differences in pharmacokinetics, pharmacodynamics, and pharmacogenetics of hydroxyurea, which could aid the optimisation of hydroxyurea for sickle cell patients in Nigeria. The objectives of the study are i. To determine the prevalence of genetic polymorphisms in metabolic enzymes and transporters relevant to the disposition of hydroxyurea in the Nigerian sickle cell disease population, ii. To develop and validate an analytical method for the quantification of hydroxyurea using high-performance liquid chromatography. iii. To evaluate the influence of genetic and other covariates on hydroxyurea disposition in the Nigerian sickle cell disease population using population pharmacokinetic modelling, iv. To investigate the relationship between hydroxyurea exposure and clinical outcomes (foetal haemoglobin, mean corpuscular volume, reduction in vaso-occlusive crises (VOC), and improved blood count) using pharmacokinetic-pharmacodynamic modelling, v. To develop physiologically-based pharmacokinetic (PBPK) models that could predict hydroxyurea concentrations in special populations of sickle cell disease patients in Nigeria i.e. pregnant women, lactating mothers, breastfed infants, and paediatrics. vi. To develop a dosing guideline for hydroxyurea therapy in Nigerian sickle cell patients. Overall, this study will provide scientific knowledge that can enhance clinical decision-making in sickle cell management within the Nigerian population, and the models could serve as a template to optimize hydroxyurea use in this population.

Who can participate

Age range

18 Years

Sex

ALL

See this in plain English?

AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

Inclusion Criteria: * Patients with confirmed diagnosis of sickle cell disease (SCD) (e.g., HbSS, HbSC) and of Nigerian descent. * Patients currently on hydroxyurea therapy or hydroxyurea-naive patients who are willing to commence hydroxyurea therapy. * Patients whose genotypic profile for the major metabolising enzymes has been previously done e.g. CYP2D6. * Patients who consent to be part of the study Exclusion Criteria: * Patients with severe comorbidities that may significantly alter pharmacokinetics (e.g., advanced renal or hepatic failure) * Patients in acute crisis at the time of sampling. * Patients with documented poor adherence to other medications previously on. * Pregnant females and lactating mothers.

Questions worth asking your doctor

Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.

1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?

Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.

Questions for the trial coordinator

The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.

1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?

A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.

What they're measuring

Increase in foetal haemoglobin

Timeframe: 6 months

Trial details

NCT IDNCT07543289

SponsorOchuko Orherhe

Sponsor typeOTHER

Study typeOBSERVATIONAL

Primary completion2026-10-30

Contact for this trial

Ochuko M. Orherhe, M.Phil.

+2348051589453 oorherhe@oauife.edu.ng

View on ClinicalTrials.gov More Sickle Cell Disease trials