Zinc supplements for bone health in sickle cell disease

Zinc Supplementation in Sickle Cell Disease: A Precursor to the Think Zinc for Bones Trial

This 12-week test gives two different daily zinc doses (25 mg or 40 mg) to people aged 15 to 40 with homozygous sickle cell disease to see which dose most changes blood markers of bone turnover.

Quick facts

• Phase: Phase 2
• Study type: Interventional
• Enrollment: 34 (estimated)
• Ages: 15 Years to 40 Years
• Sex: All
• Sponsor: University of California, San Francisco (Academic / other)
• Locations: 6 sites (Oakland, California and 5 other locations)
• Trial ID: NCT06260891 on ClinicalTrials.gov

What this trial studies

This randomized, double-blind Phase II trial will enroll 34 participants with SCD-SS or Sβ0 thalassemia across multiple U.S. centers and randomly assign them to 25 mg or 40 mg of zinc daily. Participants will have two baseline blood draws four weeks apart followed by a 12-week zinc intervention with monitoring of bone formation and resorption biomarkers and tolerability. The primary goals are to identify which biochemical markers respond to zinc supplementation and to determine the maximum tolerated dose that produces desired biomarker changes. Findings will provide dosing data for a larger future trial on the long-term impact of zinc on bone health in sickle cell disease.

Who should consider this trial

Good fit: Ideal candidates are males or females aged 15 to 40 with SCD-SS or Sβ0 thalassemia in steady state who can stop zinc supplements and meet laboratory criteria.

Not a fit: Patients on chronic transfusion with iron overload, those with vitamin D deficiency (<20 ng/mL), significant kidney disease (eGFR <30 mL/min/1.73m2), or those unable or unwilling to stop zinc supplements are unlikely to benefit or be eligible.

Why it matters

Potential benefit: If successful, the trial could identify a safe zinc dose that improves bone turnover markers and support future efforts to prevent early bone loss and fractures in young people with SCD.

How similar studies have performed: Although zinc deficiency and benefits for growth and red cell stability have been reported in SCD, the short-term effects of zinc on bone turnover biomarkers in SCD are novel and have not been previously described in the literature.

Eligibility criteria

Inclusion Criteria:

* Age: ≥ 15.0 to ≤ 40.0 years
* Diagnosis: SCD-SS or SCD-S Beta zero Thalassemia, in steady state (defined as a minimum of 2 weeks days following pain crisis)
* Male or Female

Exclusion Criteria:

* Taking any supplement containing zinc and unable/willing to stop for 3 months prior to study start
* 25-Hydroxy Vitamin D \< 20 ng/mL
* On chronic transfusion therapy (defined as \>8 Transfusions/year) and iron overloaded (defined as liver iron concentration \> 7 mg/g OR average serum ferritin \>4000 ug/L)
* Unable swallow pills or take daily supplement as instructed
* Currently participating in another investigational drug trial
* Prior diagnosis of chronic kidney disease (eGFR \< 30 mL/min/1.73m2)

Where this trial is running

Oakland, California and 5 other locations

• UCSF Benioff Children's Hospital Oakland — Oakland, California, United States (Recruiting)
• Duke University Medical Center — Durham, North Carolina, United States (Not_yet_recruiting)
• Cincinnati Children's Hospital — Cincinnati, Ohio, United States (Not_yet_recruiting)
• Children's Hospital of Philadelphia — Philadelphia, Pennsylvania, United States (Not_yet_recruiting)
• Thomas Jefferson University Hospital — Philadelphia, Pennsylvania, United States (Not_yet_recruiting)
• Baylor College of Medicine — Houston, Texas, United States (Not_yet_recruiting)

Study contacts

• Principal investigator: Ellen Fung, PhD — University of California, San Francisco
• Study coordinator: Beth Anne Martin

Conditions Sickle Cell Disease