title: Paricalcitol versus cinacalcet plus low-dose vitamin D therapy for the treatment of secondary hyperparathyroidism in patients receiving haemodialysis: results of the IMPACT SHPT study.
abstract: BACKGROUND
  Optimal treatment for secondary hyperparathyroidism (SHPT) has not been defined. The IMPACT SHPT (ClinicalTrials.gov identifier: NCT00977080) study assessed whether dose-titrated paricalcitol plus supplemental cinacalcet only for hypercalcaemia is superior to cinacalcet plus low-dose vitamin D in controlling intact parathyroid hormone (iPTH) levels in patients with SHPT on haemodialysis.
  
  
  METHODS
  In this 28-week, multicentre, open-label Phase 4 study, participants were randomly selected to receive paricalcitol or cinacalcet plus low-dose vitamin D. Randomization and analyses were stratified by mode of paricalcitol administration [intravenous (IV) or oral]. The primary efficacy end point was the proportion of subjects who achieved a mean iPTH value of 150-300 pg/mL during Weeks 21-28.
  
  
  RESULTS
  Of 272 subjects randomized, 268 received one or more dose of study drug; 101 in the IV and 110 in the oral stratum with two or more values during Weeks 21-28 were included in the primary analysis. In the IV stratum, 57.7% of subjects in the paricalcitol versus 32.7% in the cinacalcet group (P = 0.016) achieved the primary end point. In the oral stratum, the corresponding proportions of subjects were 54.4% for paricalcitol and 43.4% for cinacalcet (P = 0.260). Cochran-Mantel-Haenszel analysis, controlling for stratum, revealed overall superiority of paricalcitol (56.0%) over cinacalcet (38.2%; P = 0.010) in achieving iPTH 150-300 pg/mL during Weeks 21-28. Hypercalcaemia occurred in 4 (7.7%) and 0 (0%) of paricalcitol-treated subjects in the IV and oral strata, respectively. Hypocalcaemia occurred in 46.9% and 54.7% of cinacalcet-treated subjects in the IV and oral strata, respectively.
  
  
  CONCLUSIONS
  Paricalcitol versus cinacalcet plus low-dose vitamin D provided superior control of iPTH, with low incidence of hypercalcaemia.
authors.affiliation: Division of Nephrology, Klinikum Coburg, Coburg, Germany. markus.ketteler@klinikum-coburg.de
authors.forename: Markus
authors.initials: M
authors.lastname: Ketteler
authors.forename: Kevin J
authors.initials: KJ
authors.lastname: Martin
authors.forename: Myles
authors.initials: M
authors.lastname: Wolf
authors.forename: Michael
authors.initials: M
authors.lastname: Amdahl
authors.forename: Mario
authors.initials: M
authors.lastname: Cozzolino
authors.forename: David
authors.initials: D
authors.lastname: Goldsmith
authors.forename: Amit
authors.initials: A
authors.lastname: Sharma
authors.forename: Steven
authors.initials: S
authors.lastname: Marx
authors.forename: Samina
authors.initials: S
authors.lastname: Khan
mesh_terms: D061605:Administration, Intravenous; D000284:Administration, Oral; D000368:Aged; D015519:Bone Density; D050071:Bone Density Conservation Agents / Q000008:administration & dosage / Q000009:adverse effects; D002118:Calcium / Q000097:blood; D000069449:Cinacalcet; D004359:Drug Therapy, Combination; D004872:Ergocalciferols / Q000008:administration & dosage* / Q000009:adverse effects; D005260:Female; D006801:Humans; D006934:Hypercalcemia / Q000209:etiology; D006962:Hyperparathyroidism, Secondary / Q000097:blood / Q000188:drug therapy* / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D009281:Naphthalenes / Q000008:administration & dosage* / Q000009:adverse effects; D010281:Parathyroid Hormone / Q000097:blood; D018167:Receptors, Calcitriol / Q000819:agonists; D006435:Renal Dialysis; D051436:Renal Insufficiency, Chronic / Q000150:complications / Q000188:drug therapy / Q000628:therapy; D016896:Treatment Outcome; D014807:Vitamin D / Q000008:administration & dosage*
chemical_list: D050071:Bone Density Conservation Agents; D004872:Ergocalciferols; D009281:Naphthalenes; D010281:Parathyroid Hormone; D018167:Receptors, Calcitriol; D014807:Vitamin D; C084656:paricalcitol; D002118:Calcium; D000069449:Cinacalcet