Summary: In a 6-month placebo-controlled trial in early diabetic kidney disease, calcitriol lowered the rise in inflammation and tubular-injury biomarkers, but the reduction in albuminuria did not reach statistical significance.
PICO Summary
| Element | Detail |
|---|---|
| Population | 120 patients with controlled type 2 diabetes, albuminuria, and eGFR above 45 mL/min/1.73 m²; double-blind RCT, Indonesia. |
| Intervention | Calcitriol 0.25 mcg/day for 6 months. |
| Comparison | Placebo for 6 months. |
| Outcome | The calcitriol group had smaller rises in IL-6 (p=0.006) and KIM-1 (p=0.020) and a fall in urinary nephrin. Although albuminuria (UACR) decreased more with calcitriol, the difference was not statistically significant (p=0.099). No significant adverse events or changes in serum calcium or phosphate. |
Calcitriol in early diabetic kidney disease
RCT · early DKD · 6 months
Calcitriol blunted the rise in inflammation (IL-6) and tubular-injury (KIM-1) biomarkers, but the albuminuria reduction was not statistically significant. A favourable biomarker signal, not demonstrated renoprotection.
Expert Commentary
This is a mechanistically interesting trial that should be read for what reached significance and what did not, because the distinction matters clinically. The defensible findings are on biomarkers: calcitriol blunted rises in the inflammatory marker IL-6 and the tubular-injury marker KIM-1, with a fall in nephrin hinting at reduced podocyte stress, which is biologically coherent given vitamin D receptor effects on renal inflammation and the renin-angiotensin system. The crucial caveat is that the clinically meaningful endpoint, albuminuria, improved only as a non-significant trend at p=0.099, so this is best described as a favourable biomarker signal rather than demonstrated renoprotection. Reassuringly, calcium and phosphate did not shift and no significant adverse events occurred at this low dose. Limitations include a small sample, six months, surrogate endpoints, and the absence of hard renal outcomes. Can I use this with my patients? Not as a treatment decision. This does not justify adding calcitriol for renoprotection in diabetic kidney disease, where proven therapies such as RAS blockade, SGLT2 inhibitors, and finerenone are the priorities, but it is a reasonable signal to pursue in larger trials with albuminuria and GFR endpoints before any clinical role can be claimed.
References
Nugroho P, Lydia A, Soewondo P, et al. Modulation of renal inflammation and tubular injury by calcitriol in patients with early diabetic kidney disease: a randomized controlled trial. Ann Med. 2025;57(1):2577271. doi:10.1080/07853890.2025.2577271