First-in-human (FIH) study of CLY-124 in healthy volunteers (HV) and participants with sickle cell disease (SCD)

A Phase 1, Randomized, Placebo-Controlled, Double Blind, Single and Multiple Ascending Dose Study to Assess the Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of CLY-124 in Healthy Volunteers and Participants with Sickle Cell Disease

Status

Recruiting

Phases

Phase 1

Study type

Interventional

Source

PACTR

Registry ID

PACTR202505486265852

Enrollment

183

Registered

2025-05-13

Start date

2025-06-02

Completion date

Unknown

Last updated

2026-09-14

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Haematological Disorders

Interventions

CLY124

Placebo

Eligibility

Sex/Gender

All

Inclusion criteria

Inclusion criteria: 1.Adults ages 18-55 years old with a confirmed diagnosis of sickle cell disease 2.Participant has a BMI of 17.5 to 30.0 kg/m2 and bodyweight =45 kg at Screening Females of childbearing potential must use effective contraception; males must agree to appropriate contraceptive measures 3. Participants taking standard of care hydroxyurea must be on a stable regimen for 3 months prior to screening

Exclusion criteria

Exclusion criteria: 1. Recent participation in another investigational study. 2. History of certain malignancies unless adequately treated and stable. 3. Recent major surgery. 4. History of significant or uncontrolled medical conditions that could interfere with study participation. 5. Clinically significant cardiovascular conditions (e.g. uncontrolled hypertension). 6. Participant has any active infections at time of Screening. 7. Positive screening for key infectious diseases (hepatitis B, hepatitis C, HIV).

Design outcomes

Primary

Measure	Time frame
Primary Outcome 1.To evaluate the safety and tolerability of CLY-124 following single and multiple dose administration in healthy volunteers and participants with sickle cell disease. 2. To evaluate the pharmacokinetic profile of CLY-124 and its metabolites following administration in healthy volunteers and participants with sickle cell disease. Outcome 1. Incidence and severity of adverse events, changes in clinical laboratory parameters, vital signs, and other safety assessments following administration of CLY-124. 2. Plasma pharmacokinetic parameters of CLY-124 and its metabolites following single and multiple dose administration as defined in the study protocol. ;Primary Outcome 1.To evaluate the safety and tolerability of CLY-124 following single and multiple dose administration in healthy volunteers and participants with sickle cell disease. 2. To evaluate the pharmacokinetic profile of CLY-124 and its metabolites following administration in healthy volunteers and participants with sickle cell disease. Outcome	—

Measure

Time frame

Primary Outcome 1.To evaluate the safety and tolerability of CLY-124 following single and multiple dose administration in healthy volunteers and participants with sickle cell disease. 2. To evaluate the pharmacokinetic profile of CLY-124 and its metabolites following administration in healthy volunteers and participants with sickle cell disease. Outcome 1. Incidence and severity of adverse events, changes in clinical laboratory parameters, vital signs, and other safety assessments following administration of CLY-124. 2. Plasma pharmacokinetic parameters of CLY-124 and its metabolites following single and multiple dose administration as defined in the study protocol. ;Primary Outcome 1.To evaluate the safety and tolerability of CLY-124 following single and multiple dose administration in healthy volunteers and participants with sickle cell disease. 2. To evaluate the pharmacokinetic profile of CLY-124 and its metabolites following administration in healthy volunteers and participants with sickle cell disease. Outcome

—

Secondary

Measure	Time frame
Secondary Outcome Relationship between CLY-124 exposure and changes in fetal hemoglobin (HbF) levels in participants with sickle cell disease. Outcome Change from baseline in pharmacodynamic markers of fetal hemoglobin production in participants with sickle cell disease, as defined in the study protocol.;Secondary Outcome Relationship between CLY-124 exposure and changes in fetal hemoglobin (HbF) levels in participants with sickle cell disease. Outcome Change from baseline in pharmacodynamic markers of fetal hemoglobin production in par	—

Measure

Time frame

Secondary Outcome Relationship between CLY-124 exposure and changes in fetal hemoglobin (HbF) levels in participants with sickle cell disease. Outcome Change from baseline in pharmacodynamic markers of fetal hemoglobin production in participants with sickle cell disease, as defined in the study protocol.;Secondary Outcome Relationship between CLY-124 exposure and changes in fetal hemoglobin (HbF) levels in participants with sickle cell disease. Outcome Change from baseline in pharmacodynamic markers of fetal hemoglobin production in par

—

Countries

Ghana, Kenya

Contacts

Public Contactmichelle Botha

Assc Dr Global Site Activation

michelle.botha@iqvia.com+27126712334

Outcome results

None listed

Source: PACTR (via WHO ICTRP) · Data processed: Sep 19, 2026