No, Parsabiv (etelcalcetide) and cinacalcet are not the same drug—they are two different calcimimetic agents used for the same indication.
Key Differences Between the Two Drugs
Parsabiv (etelcalcetide) and cinacalcet are both calcimimetics that work on the calcium-sensing receptor to lower PTH, but they differ fundamentally in their chemical structure, route of administration, and pharmacologic properties. 1
Chemical and Pharmacologic Distinctions
Cinacalcet is an oral, small-molecule calcimimetic that has been available since 2004 and requires daily oral administration 2, 3
Etelcalcetide (Parsabiv) is a small synthetic polycationic peptide administered intravenously three times weekly at the end of hemodialysis sessions 3, 4
Etelcalcetide has a shorter half-life and is cleared by hemodialysis, whereas cinacalcet is metabolized hepatically 3
Clinical Efficacy Comparison
Etelcalcetide demonstrates approximately 10% greater reduction in serum PTH levels compared to cinacalcet 3, 5
Both agents have similar or superior efficacy to cinacalcet for PTH reduction in CKD G5D patients, though neither has demonstrated survival benefits 1
Patients switching from cinacalcet to etelcalcetide, particularly those who were nonadherent to oral therapy, show significant improvements in PTH control 5
Side Effect Profiles
Gastrointestinal tolerability: Etelcalcetide does NOT offer better gastrointestinal tolerance than cinacalcet, despite being administered intravenously 3
Hypocalcemia risk: Etelcalcetide carries a GREATER risk of hypocalcemia compared to cinacalcet 3, 5
Cinacalcet causes nausea (RR 2.02) and vomiting (RR 1.97) as common adverse effects 1, 6
Practical Advantages of Intravenous Formulation
The primary advantage of etelcalcetide is improved medication adherence by eliminating the pill burden, as it is administered directly during dialysis sessions 1, 3
This is particularly beneficial for patients who were nonadherent to oral cinacalcet (approximately 38% in one study), who showed significant improvements in PTH control after switching 5
FDA-Approved Switching Protocol
The FDA label for cinacalcet includes specific guidance for switching from Parsabiv (etelcalcetide) to cinacalcet tablets 2
The dose conversion factor for switching from cinacalcet to etelcalcetide is: etelcalcetide dose/session = 0.111 × mg cinacalcet/day + 0.96 5
Common Pitfalls to Avoid
Do not assume intravenous administration means fewer side effects—etelcalcetide has comparable GI side effects and higher hypocalcemia risk 3
Do not use these agents interchangeably without dose adjustment—they require specific conversion calculations when switching 2, 5
Both agents require the same monitoring for hypocalcemia, which occurs in approximately 60 per 1,000 patients treated for one year with cinacalcet (RR 7.38) 6, 7