Trial Outcomes & Findings for Hydroxyurea and EPO in Sickle Cell Disease (NCT NCT05451940)

NCT ID: NCT05451940

Last Updated: 2026-01-07

Results Overview

Hb response is defined as a Hb increase of ≥ 1.0 g/dL at 12 weeks compared to baseline

Recruitment status

COMPLETED

Study phase

PHASE1/PHASE2

Target enrollment

17 participants

Primary outcome timeframe

Baseline to 12 weeks

Results posted on

2026-01-07

Participant Flow

Potential participants will be identified through outpatient hematology clinics at Lagos University Teaching Hospital and UPMC Adult Sickle Cell Clinic. Treating clinicians may refer eligible patients, and study staff may review clinic schedules and electronic health records to identify potentially eligible individuals. IRB-approved recruitment materials may be used, and interested individuals may self-refer by contacting the study team.

Interested individuals will undergo an informed consent process prior to any study-specific procedures. Eligibility will be confirmed through review of medical history, laboratory values, and other inclusion and exclusion criteria. Participants who meet all eligibility criteria will be enrolled and assigned to the study intervention.

Participant milestones

Participant milestones
Measure	Erythropoietin Subjects on a stable dose of hydroxyurea will be treated with increasing doses of subcutaneous erythropoietin (EPO) as tolerated for an initial 12 weeks, during which the main safety and efficacy endpoints (including the primary endpoint of hemoglobin response) will be assessed. Subjects may continue on treatment for an additional 12 weeks as clinically indicated, with assessment of additional endpoints at the end of the 24-week study period.
Treatment Period STARTED	17
Treatment Period COMPLETED	16
Treatment Period NOT COMPLETED	1
Observation Period STARTED	16
Observation Period COMPLETED	16
Observation Period NOT COMPLETED	0

Reasons for withdrawal

Reasons for withdrawal
Measure	Erythropoietin Subjects on a stable dose of hydroxyurea will be treated with increasing doses of subcutaneous erythropoietin (EPO) as tolerated for an initial 12 weeks, during which the main safety and efficacy endpoints (including the primary endpoint of hemoglobin response) will be assessed. Subjects may continue on treatment for an additional 12 weeks as clinically indicated, with assessment of additional endpoints at the end of the 24-week study period.
Treatment Period Physician Decision	1

Baseline Characteristics

All participants self-identified as African, African-American, or Black

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Erythropoietin n=16 Participants Subjects on a stable dose of hydroxyurea will be treated with increasing doses of subcutaneous erythropoietin (EPO) as tolerated for an initial 12 weeks, during which the main safety and efficacy endpoints (including the primary endpoint of hemoglobin response) will be assessed. Subjects may continue on treatment for an additional 12 weeks as clinically indicated, with assessment of additional endpoints at the end of the 24-week study period.
Age, Continuous	30 Year n=37 Participants
Sex: Female, Male Female	9 Participants n=37 Participants
Sex: Female, Male Male	7 Participants n=37 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants n=37 Participants • All participants self-identified as African, African-American, or Black
Race (NIH/OMB) Asian	0 Participants n=37 Participants • All participants self-identified as African, African-American, or Black
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=37 Participants • All participants self-identified as African, African-American, or Black
Race (NIH/OMB) Black or African American	16 Participants n=37 Participants • All participants self-identified as African, African-American, or Black
Race (NIH/OMB) White	0 Participants n=37 Participants • All participants self-identified as African, African-American, or Black
Race (NIH/OMB) More than one race	0 Participants n=37 Participants • All participants self-identified as African, African-American, or Black
Race (NIH/OMB) Unknown or Not Reported	0 Participants n=37 Participants • All participants self-identified as African, African-American, or Black
Ethnicity (NIH/OMB) Hispanic or Latino	0 Participants n=37 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	16 Participants n=37 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	0 Participants n=37 Participants
Region of Enrollment Nigeria	14 Participants n=37 Participants
Region of Enrollment United States	2 Participants n=37 Participants
Sickle cell disease genotype Hemoglobin SS disease	16 Participants n=37 Participants
Sickle cell disease genotype Hemoglobin SC disease	0 Participants n=37 Participants
Sickle cell disease genotype Hemoglobin S/beta0-thalassemia	0 Participants n=37 Participants
Sickle cell disease genotype Hemoglobin S/beta+-thalassemia	0 Participants n=37 Participants
Sickle cell disease genotype Other	0 Participants n=37 Participants

PRIMARY outcome

Timeframe: Baseline to 12 weeks

Population: All enrolled participants who have completed baseline and end of treatment testing, regardless of duration of treatment with EPO, will be included in the analysis.

Hb response is defined as a Hb increase of ≥ 1.0 g/dL at 12 weeks compared to baseline

Outcome measures

Outcome measures
Measure	Erythropoietin n=16 Participants Subjects on a stable dose of hydroxyurea will be treated with increasing doses of subcutaneous erythropoietin (EPO) as tolerated for an initial 12 weeks, during which the main safety and efficacy endpoints (including the primary endpoint of hemoglobin response) will be assessed. Subjects may continue on treatment for an additional 12 weeks as clinically indicated, with assessment of additional endpoints at the end of the 24-week study period.
Percentage of Participants With Hemoglobin (Hb) Response	15 Participants

SECONDARY outcome

Timeframe: Baseline to 12 weeks

Population: All enrolled participants who have completed baseline and end-of-treatment (12-week) testing, regardless of duration of treatment with EPO, will be included in the analysis.

Annualized number of units of simple red blood cell transfusions received in the 12 months before treatment initiation, compared to during the treatment period

Outcome measures

Outcome measures
Measure	Erythropoietin n=16 Participants Subjects on a stable dose of hydroxyurea will be treated with increasing doses of subcutaneous erythropoietin (EPO) as tolerated for an initial 12 weeks, during which the main safety and efficacy endpoints (including the primary endpoint of hemoglobin response) will be assessed. Subjects may continue on treatment for an additional 12 weeks as clinically indicated, with assessment of additional endpoints at the end of the 24-week study period.
Change in Number of Blood Transfusions Per Year	-1.1 Transfusions per year Standard Deviation 3.7

OTHER_PRE_SPECIFIED outcome

Timeframe: Baseline to 12 weeks

Population: All enrolled participants who have completed baseline and end-of-treatment (12-week) testing, regardless of duration of treatment with EPO, will be included in the analysis.

Mean change in Hb at 12 weeks compared to baseline

Outcome measures

Outcome measures
Measure	Erythropoietin n=16 Participants Subjects on a stable dose of hydroxyurea will be treated with increasing doses of subcutaneous erythropoietin (EPO) as tolerated for an initial 12 weeks, during which the main safety and efficacy endpoints (including the primary endpoint of hemoglobin response) will be assessed. Subjects may continue on treatment for an additional 12 weeks as clinically indicated, with assessment of additional endpoints at the end of the 24-week study period.
Changes in Hemoglobin (Hb)	3.0 g/dL Standard Deviation 1.6

Adverse Events

Erythropoietin

Serious events: 2 serious events

Other events: 15 other events

Deaths: 0 deaths

Serious adverse events

Serious adverse events
Measure	Erythropoietin n=17 participants at risk Subjects on a stable dose of hydroxyurea will be treated with increasing doses of subcutaneous erythropoietin (EPO) as tolerated for an initial 12 weeks, during which the main safety and efficacy endpoints (including the primary endpoint of hemoglobin response) will be assessed. Subjects may continue on treatment for an additional 12 weeks as clinically indicated, with assessment of additional endpoints at the end of the 24-week study period.
Congenital, familial and genetic disorders Vaso-occlusive crisis	5.9% 1/17 • Number of events 3 • From study drug initiation to the end of the treatment period (up to 12 weeks)
Neoplasms benign, malignant and unspecified (incl cysts and polyps) Myelodysplastic syndrome	5.9% 1/17 • Number of events 1 • From study drug initiation to the end of the treatment period (up to 12 weeks)

Other adverse events

Other adverse events
Measure	Erythropoietin n=17 participants at risk Subjects on a stable dose of hydroxyurea will be treated with increasing doses of subcutaneous erythropoietin (EPO) as tolerated for an initial 12 weeks, during which the main safety and efficacy endpoints (including the primary endpoint of hemoglobin response) will be assessed. Subjects may continue on treatment for an additional 12 weeks as clinically indicated, with assessment of additional endpoints at the end of the 24-week study period.
Skin and subcutaneous tissue disorders Skin ulceration	5.9% 1/17 • Number of events 1 • From study drug initiation to the end of the treatment period (up to 12 weeks)
Infections and infestations Upper respiratory infection	5.9% 1/17 • Number of events 1 • From study drug initiation to the end of the treatment period (up to 12 weeks)
Gastrointestinal disorders Anorexia	5.9% 1/17 • Number of events 1 • From study drug initiation to the end of the treatment period (up to 12 weeks)
Cardiac disorders Cardiac troponin I increased	5.9% 1/17 • Number of events 1 • From study drug initiation to the end of the treatment period (up to 12 weeks)
Hepatobiliary disorders Cholelithiasis	5.9% 1/17 • Number of events 1 • From study drug initiation to the end of the treatment period (up to 12 weeks)
Eye disorders Conjunctivitis infective	5.9% 1/17 • Number of events 1 • From study drug initiation to the end of the treatment period (up to 12 weeks)
Gastrointestinal disorders Diarrhea	5.9% 1/17 • Number of events 1 • From study drug initiation to the end of the treatment period (up to 12 weeks)
Nervous system disorders Dizziness	11.8% 2/17 • Number of events 2 • From study drug initiation to the end of the treatment period (up to 12 weeks)
Nervous system disorders Dysgeusia	5.9% 1/17 • Number of events 1 • From study drug initiation to the end of the treatment period (up to 12 weeks)
Blood and lymphatic system disorders Edema limbs	5.9% 1/17 • Number of events 1 • From study drug initiation to the end of the treatment period (up to 12 weeks)
Nervous system disorders Headache	5.9% 1/17 • Number of events 1 • From study drug initiation to the end of the treatment period (up to 12 weeks)
Infections and infestations Lung infection	5.9% 1/17 • Number of events 1 • From study drug initiation to the end of the treatment period (up to 12 weeks)
Reproductive system and breast disorders Menorrhagia	5.9% 1/17 • Number of events 1 • From study drug initiation to the end of the treatment period (up to 12 weeks)
Investigations Neutrophil count decreased	47.1% 8/17 • Number of events 10 • From study drug initiation to the end of the treatment period (up to 12 weeks)
General disorders Pain	5.9% 1/17 • Number of events 1 • From study drug initiation to the end of the treatment period (up to 12 weeks)
Musculoskeletal and connective tissue disorders Pain in extremity	11.8% 2/17 • Number of events 2 • From study drug initiation to the end of the treatment period (up to 12 weeks)
Cardiac disorders Palpitations	5.9% 1/17 • Number of events 1 • From study drug initiation to the end of the treatment period (up to 12 weeks)
Investigations Platelet count decreased	5.9% 1/17 • Number of events 1 • From study drug initiation to the end of the treatment period (up to 12 weeks)
Congenital, familial and genetic disorders Priapism	17.6% 3/17 • Number of events 3 • From study drug initiation to the end of the treatment period (up to 12 weeks)
Skin and subcutaneous tissue disorders Skin hyperpigmentation	5.9% 1/17 • Number of events 1 • From study drug initiation to the end of the treatment period (up to 12 weeks)
Infections and infestations Skin infection	5.9% 1/17 • Number of events 1 • From study drug initiation to the end of the treatment period (up to 12 weeks)

Additional Information

Julia Z. Xu, MD

University of Pittsburgh

Phone: 412-648-6466

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place