YS RAJARAM1, H DIXON 2, C MCBRIDE3, H GOCK1, 3
1Department of Nephrology; 2Pharmacy Department; 3Department of Medicine, University of Melbourne, St Vincent’s Hospital Melbourne, AUSTRALIA.
Background: Cinacalcet, a patented calcimimetic was PBS-listed 2008-2015 to treat secondary hyperparathyroidism (hPTH) in stage-5D CKD and reputed to improve surrogate biochemical markers of mortality and parathyroidectomy. It was PBS-delisted after the EVOLVE study demonstrated no survival benefit.
Aim: To assess at our centre: (1) Cinacalcet usage before and during PBS-listing and after PBS-de-listing, (2) Biochemical outcomes of patients that initially remained on Cinacalcet post-PBS-delisting, (3) hPTH parathyroidectomy rate after PBS-delisting.
Methods: Pharmacy records were used to identify patients on Cinacalcet (2006-16). From the date of PBS-delisting (Aug 1st, 2015), serum Calcium, Phosphate and PTH level were obtained from hospital records. If Cinacalcet was later ceased, the same parameters were reviewed 3 months post-cessation. We also identified the annual number of hPTH parathyroidectomy between 2006-2016 to calculate the parathyroidectomy rate [no. of hPTH parathyroidectomy/total dialysis patients] x 100.
Results: The number of patients prescribed Cinacalcet was 10 prior to PBS-listing (2006-7) and peaked at 67 during PBS-listing (2010). There were 21 patients on Cinacalcet after delisting. Among those, 14 (67%) patients subsequently ceased, 3 (14%) proceeded to parathyroidectomy and 4 (19%) remain on Cinacalcet to date. Of those that ceased, the mean serum calcium, phosphate and PTH levels were 2.46±0.19, 1.40±0.47, 383±287 respectively and post-cessation were 2.53±0.21 (p=0.14), 1.34±0.66 (p=0.31), 464±403 (p=0.33) respectively. The parathyroidectomy rate was 1.73% (2006-7) before PBS-listing, 1.55% (2008-14) while PBS-listed and 2.43% (2015-6) post-PBS-delisting.
Conclusions: No significant change in biochemical profile and PTH was observed with cessation of Cinacalcet and return to standard therapy. However, there was an increased number of hPTH parathyroidectomy following PBS-delisting that we hypothesise will be transient.