A Randomized Trial of Cinacalcet versus Vitamin D Analogs as Monotherapy in Secondary Hyperparathyroidism (PARADIGM)

作者：Wetmore James B^*; Gurevich Konstantin; Sprague Stuart; Da Roza Gerald; Buerkert John; Reiner Maureen; Goodman William; Cooper Kerry

来源：Clinical Journal of the American Society of Nephrology, 2015, 10(6): 1031-1040.

DOI：10.2215/CJN.07050714

Background and objectives Direct comparison of cinacalcet and vitamin D analogs as monotherapies to lower parathyroid hormone (PTH) levels has not been undertaken.
Design, setting, participants, & measurements This was a prospective, multicenter, phase 4, randomized, open-label study that enrolled participants from 2010 to 2012. Adult participants (n=312) on hemodialysis with PTH >450 pg/ml were randomized 1:1 to 12 months of treatment with either cinacalcet (n=155) or vitamin D. analogs (n=157) to evaluate the mean percentage change in plasma PTH level (primary end point) and the proportion of participants achieving plasma PTH <300 pg/ml or a >= 30% decrease in PTH (secondary end points). A preplanned analysis to determine whether there were important region-by-treatment interactions was also undertaken.
Results Baseline mean PTH was 846 pg/ml (n=155) for cinacalcet and 816 pg/ml (n=157) for vitamin D analog therapy. The mean (95% confidence interval) percentage change from baseline in PTH was -12.1% (-20.0% to -4.1%) in the cinacalcet arm and -7.0% (-14.9% to 0.8%) in the vitamin D analog arm, a difference of 5.0% (-15.4% to 5.4%) (P=0.35). Similarly, there was no difference in achievement of secondary efficacy end points between arms (19.4% and 15.3% of participants with PTH <= 300 pg/ml and 42.6% and 33.8% of participants had a PTH reduction >30% in the cinacalcet and vitamin D analog arms, respectively). A prespecified analysis revealed a large treatment-by-region interaction, with nominally greater response to cinacalcet compared with vitamin D analogs in non United States participants (US versus non-US participants, P<0.001). Hypocalcemia was more common in the cinacalcet arm, whereas hypercalcemia and hyperphosphatemia occurred more often in the vitamin D analog arm.
Conclusions Participants had similar modest reductions in PTH with either cinacalcet or vitamin D analog monotherapy over 52 weeks of treatment, but effects varied by region. Treatments differed with regard to effect on calcium and phosphorus levels.

• 出版日期2015-6