# Realizing Effectiveness Across Continents with Hydroxyurea(REACH): A Phase I/II Pilot Study of Hyroxyurea for Children with Sickle Cell Anemia

> **NIH NIH U01** · CINCINNATI CHILDRENS HOSP MED CTR · 2024 · $1,423,588

## Abstract

ABSTRACT
Sickle cell anemia (SCA) is among the world’s most common inherited blood disorders, and causes severe morbidity and early
mortality. SCA is highly prevalent in sub-Saharan Africa, affecting over 300,000 births annually, with an estimated 30% increase
in the next generation. To address the burden of SCA within Africa, neonatal screening is needed to establish the proper
diagnosis, and hydroxyurea treatment is needed to ameliorate morbidity and decrease mortality. Hydroxyurea is listed by
the World Health Organization as an Essential Medicine for children with SCA, representing the only realistic and affordable
disease-modifying therapy in this setting. Until recently, hydroxyurea had been studied primarily in high-income countries,
with virtually no data available regarding its safe and effective use in Africa. To address this critical unmet need, we designed
and launched REACH (Realizing Effectiveness Across Continents with Hydroxyurea, NCT01966731), a prospective open-label
study of hydroxyurea for young children with SCA in sub-Saharan Africa. In the current funding period, 606 children in four
African countries received hydroxyurea escalated to maximum tolerated dose (MTD). Despite COVID, our research teams in
Angola, Democratic Republic of Congo, Kenya, and Uganda collected unprecedented data on the safety, feasibility, and
benefits of hydroxyurea for SCA in Africa, with >3000 patient-years of treatment. We documented reductions in sickle-
related clinical events and found unexpected reductions in malaria, transfusions, and death. We performed whole exome
sequencing to investigate inter-patient variability including hydroxyurea pharmacokinetics, pharmacodynamics, and
pharmacogenomics. In the renewal, we will make additional contributions by extending hydroxyurea treatment to this
unique cohort, whose average age is now 11 years and soon entering puberty, using a continued supply of hydroxyurea
donated by Bristol Myers Squibb. Though our initial results are encouraging, REACH does not have a placebo-controlled
cohort for comparison. Accordingly, we will enroll a new cohort of age-matched children with SCA at all four sites, to provide
pre-treatment data for comparison to our treated cohort. In the first specific aim, we will assess the long-term effects of
hydroxyurea at MTD to ameliorate SCA-related clinical complications and preserve organ function (especially brain but
also kidneys, spleen, and eyes). We will obtain longitudinal data on the effects of hydroxyurea at MTD on physical
growth, sexual development, and overall reproductive health, and collect serial DNA to test for the emergence of clonal
hematopoiesis. In the second aim, we will investigate mechanisms by which hydroxyurea reduces malaria infections,
combining epidemiological data with in vitro parasite invasion assays and an agnostic search for protective genetic
polymorphisms. In the third aim, we will simplify and optimize hydroxyurea treatment using novel and innova...

## Key facts

- **NIH application ID:** 10908303
- **Project number:** 5U01HL133883-08
- **Recipient organization:** CINCINNATI CHILDRENS HOSP MED CTR
- **Principal Investigator:** Russell E Ware
- **Activity code:** U01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2024
- **Award amount:** $1,423,588
- **Award type:** 5
- **Project period:** 2017-08-01 → 2027-07-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10908303

## Citation

> US National Institutes of Health, RePORTER application 10908303, Realizing Effectiveness Across Continents with Hydroxyurea(REACH): A Phase I/II Pilot Study of Hyroxyurea for Children with Sickle Cell Anemia (5U01HL133883-08). Retrieved via AI Analytics 2026-05-22 from https://api.ai-analytics.org/grant/nih/10908303. Licensed CC0.

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