Testing a new vitamin D treatment for kidney failure patients on dialysis

DePTH: De-emphasize Parathyroid Hormone

Phase 2 Interventional University of Washington · NCT06288451

This study is testing a new oral vitamin D treatment for kidney failure patients on dialysis to see if it can improve their bone health and lower heart risks compared to the usual vitamin D injections.

Quick facts

PhasePhase 2
Study typeInterventional
Enrollment90 (estimated)
Ages18 Years and up
SexAll
SponsorUniversity of Washington Academic / other
Locations1 site (Seattle, Washington)
Trial IDNCT06288451 on ClinicalTrials.gov

What this trial studies

The DePTH Study is a 12-month clinical trial that investigates the effects of a low fixed-dose oral calcitriol on patients with secondary hyperparathyroidism and kidney failure undergoing hemodialysis. This pragmatic, randomized, open-label trial compares the new treatment to the standard care of variably-dosed intravenous activated vitamin D. The study aims to assess the safety and effectiveness of the oral treatment in improving mineral metabolism, bone turnover, and reducing cardiovascular risks associated with kidney disease. Participants will be recruited from hemodialysis centers in Seattle and will be randomized to receive either the new treatment or the usual care.

Who should consider this trial

Good fit: Ideal candidates are adults aged 18 and older with kidney failure on in-center hemodialysis and elevated parathyroid hormone levels.

Not a fit: Patients with severe secondary hyperparathyroidism or those who have had a parathyroidectomy may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could provide a safer and more effective treatment option for patients with kidney failure and secondary hyperparathyroidism.

How similar studies have performed: While the approach of using low fixed-dose oral calcitriol is novel, previous studies have indicated that current high-dose vitamin D treatments may not improve health outcomes, suggesting a need for alternative strategies.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

1. Age \>=18 years
2. Kidney failure treated with in-center hemodialysis
3. PTH \>=150 pg/mL x 2 consecutive measures at least 1 month apart or active IV activated vitamin D treatment using the NKC protocol

Exclusion Criteria:

1. History of parathyroidectomy or calciphylaxis
2. Severe secondary hyperparathyroidism (PTH \>=600 pg/mL x 2 consecutive measures at least 1 month apart despite paricalcitol \>=10 mcg 3x/week or doxercalciferol \>=5 mcg 3x/week or cinacalcet \>30 mg/d)
3. Calcium \>9.8 mg/dL
4. Phosphate \>9 mg/dL
5. Cholestyramine, phenytoin/phenobarbital, or ketoconazole use
6. Breast-feeding mothers
7. Inability to provide informed consent and no legally authorized representative

Where this trial is running

Seattle, Washington

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Kidney Failure, ChronicChronic Kidney Disease-Mineral and Bone Disorder
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.