Strugnell S. A., Csomor P., Ashfaq A., Bishop C. W. : Evaluation of Therapies for Secondary Hyperparathyroidism Associated with Vitamin D Insufficiency in Chronic Kidney Disease. Kidney Diseases DOI.org/10.1159/000529523
The therapy of secondary hyperparathyroidism (SHPTH) in patients with advanced chronic kidney disease (CKD) presenting with 25-hydroxyvitamin D deficiency is not well established. Three approaches are mainly employed; namely, use of extended-release calcifediol (ERC); use of immediate-release, high-dose cholecalciferol (or ergocalciferol) (ICR); use of a combination of paracalcitol (or calcitriol) and low-dose cholecalciferol/ergocalciferol (PLCD). The comparative advantages of these strategies have not been fully evaluated.
Strugnell and co-workers conducted a small randomized trial (n = 62) of these 3 strategies in patients with stage 4 CKD and elevated iPTH and reduced 25-hydroxyvitamin D levels. The trial was short term (8 weeks in duration) and was stopped prematurely due to the impact of the COVID-19 pandemic on recruitment. The primary end-points were the absolute and relative changes in serum total 25-hydroxyvitamin D and iPTH levels.
At baseline, the mean 25-hydroxyvitamin D level was 20.6 ± 6.6 ng/mL and the mean iPTH level was 148 ± 90 pg/mL. The 25-hydroxyvitamin D levels increased with ERC, but not with IRC or PLCD. The iPTH levels decreased with ERC and PLCD, but not with IRC. Hypercalcemia was seen uncommonly only with PLDC, and hyperphosphatemia was seen occasionally with ERC.
Although the small size, short duration, and underpowered nature of this trial limits any firm conclusions, it does appear that ERC has advantages for treatments of patients with advanced CKD and vitamin D deficiency accompanied by SHPTH.