Is etelcalcetide FDA-approved, and what does the research show?

What is etelcalcetide?

Etelcalcetide is a synthetic peptide, a short chain of amino acids, the building blocks of proteins ¹. The label's chemical name describes seven amino acids in a row, with an eighth joined to the first by a sulfur bridge ¹. It is sold as Parsabiv, a solution for intravenous injection, which means injection into a vein ¹.

The label calls it a "calcium-sensing receptor agonist," a drug that acts on the sensor parathyroid cells use to read calcium ¹. Those cells release parathyroid hormone, written PTH ¹. In secondary hyperparathyroidism the glands release too much PTH, and "secondary" means another illness, here kidney disease, lies behind it.

The published report of one etelcalcetide trial says the condition "contributes to extraskeletal calcification," meaning calcium deposits outside the bones ⁴. It adds that the condition "is associated with all-cause and cardiovascular mortality," deaths from any cause and from heart and blood-vessel disease ⁴. That describes the condition, not an effect of the drug ⁴. The trial measured PTH in the blood, and its report says further studies are needed "to assess clinical outcomes" ⁴.

Etelcalcetide is not a wellness, weight-loss or performance peptide. The label's use is in adults on hemodialysis ¹. Hemodialysis is the treatment in which blood is passed through a filter, the dialyzer, when the kidneys have failed.

Is etelcalcetide FDA-approved?

Yes, as a prescription drug for one group of patients. FDA approved Parsabiv (etelcalcetide) on February 7, 2017, under new drug application (NDA) 208325 ². Drugs@FDA lists all three Parsabiv products with marketing status "Prescription" as of November 9, 2026, the date of the record's data ². The carton reads "Rx Only" ¹.

The label's indication is one sentence. Parsabiv "is indicated for the treatment of secondary hyperparathyroidism (HPT) in adult patients with chronic kidney disease (CKD) on hemodialysis" ⁵, ¹. For a reader, the status means an approved product with an FDA label, dispensed by prescription for the patients that label names ¹, ².

The label also sets limits. It says Parsabiv "has not been studied in adult patients with parathyroid carcinoma, primary hyperparathyroidism, or with chronic kidney disease who are not on hemodialysis and is not recommended for use in these populations" ¹. Parathyroid carcinoma is cancer of a parathyroid gland, and primary hyperparathyroidism is overactivity that begins in the glands themselves. For children, the label says safety and efficacy "have not been established in pediatric patients" ¹.

See the FDA status of every peptide, updated weekly.

How does etelcalcetide work?

The account is the label's ¹. Etelcalcetide is a calcimimetic, a drug that makes the calcium-sensing receptor (CaSR) respond more strongly to calcium ¹. In the label's words, it "binds to the CaSR and enhances activation of the receptor by extracellular calcium," the calcium outside the cells ¹. "Activation of the CaSR on parathyroid chief cells decreases PTH secretion" ¹.

The fall in PTH brought a fall in blood calcium ¹. With dosing three times a week in the studies, the effect on PTH held through the 6-month dosing period ¹.

In people on hemodialysis, dialysis itself is "the predominant elimination pathway" ¹. That explains the timing. The label says it "is removed by the dialyzer membrane and must be administered after blood is no longer circulating through the dialyzer" ¹. Its effective half-life, the time for the blood level to fall by half, was 3 to 4 days ¹.

What does the research show?

The evidence level is Approved for a use, because FDA approved etelcalcetide for secondary hyperparathyroidism in adults with chronic kidney disease on hemodialysis ¹. The label rests on two 26-week studies that were randomized, double-blind and placebo-controlled ¹. That means chance decided who got etelcalcetide and who got a placebo, a dummy injection, and neither patients nor doctors knew which. Study 1 enrolled 508 patients and Study 2 enrolled 515, all on hemodialysis three times a week ¹. Their mean PTH at the start was 834 and 848 picograms per milliliter ¹.

The main measure was the share of patients whose PTH fell by more than 30 percent from its starting level, averaged over weeks 20 through 27 ¹. In Study 1 that was 196 of 254 patients on etelcalcetide (77 percent) against 28 of 254 on placebo (11 percent) ¹. In Study 2 it was 201 of 255 (79 percent) against 29 of 260 (11 percent) ¹.

The label's counts use a statistical method that estimates missing measurements ¹. A published report of two trials with the same numbers of patients in each group counts 74.0 percent against 8.3 percent, and 75.3 percent against 9.6 percent ³. FDA's statistical review names the two studies, 20120229 and 20120230, and both registry records list this report ⁶, ⁷, ⁸.

Mean PTH fell from 849 to 424 on etelcalcetide in Study 1 and rose from 820 to 898 on placebo ¹. In Study 2 it fell from 845 to 416 on etelcalcetide and rose from 852 to 971 on placebo ¹. A PTH of 300 picograms per milliliter or lower was reached by 52 and 56 percent of the etelcalcetide groups, against 6 and 5 percent on placebo ¹.

Blood calcium fell by 7.0 percent in both etelcalcetide groups and changed by less than 1 percent on placebo ¹. Phosphate fell by 8.8 and 7.2 percent on etelcalcetide, against 3.6 and 0.3 percent on placebo ¹. The label's table gives p = 0.08 against placebo for Study 1's phosphate fall and p < 0.01 for Study 2's ¹.

The label says Parsabiv lowered PTH "regardless of" starting PTH, years on dialysis, earlier cinacalcet or vitamin D drugs ¹. Cinacalcet is a calcimimetic taken by mouth ⁴. Among patients who chose to join an extension phase, the reductions "were maintained for up to 78 weeks of treatment" ¹.

Studied in people against another drug: a randomized, double-blind trial compared etelcalcetide with cinacalcet in 683 patients on hemodialysis ⁴. Entry required a PTH higher than 500 picograms per milliliter "on active therapy," meaning while already receiving treatment ⁴. The trial ran at 164 sites in the United States, Canada, Europe, Russia and New Zealand, and Amgen sponsored it ⁴, ⁹. The label says Parsabiv is made for "a wholly owned subsidiary of Amgen, Inc." ¹.

Each patient received one real drug and one dummy: 340 got intravenous etelcalcetide with an oral placebo, and 343 got oral cinacalcet with a placebo injection ⁴. Treatment lasted 26 weeks ⁴.

A PTH fall of more than 30 percent was reached by 232 of 340 patients on etelcalcetide (68.2 percent) and 198 of 343 on cinacalcet (57.7 percent) ⁴. The difference was 10.5 percentage points, with a 95 percent confidence interval, the range that likely holds the true figure, of 3.5 to 17.5 ⁴. The trial was built to test noninferiority, whether etelcalcetide was no worse than cinacalcet by a set margin ⁴. It met that test and the stricter test of superiority, whether more patients on etelcalcetide than on cinacalcet reached the PTH fall ⁴. A fall of more than 50 percent was reached by 178 patients on etelcalcetide (52.4 percent) against 138 on cinacalcet (40.2 percent) ⁴.

Self-reported nausea or vomiting was a secondary end point, a lesser pre-set measure ⁴. In the registry's results, nausea or vomiting occurred on a mean 0.4 days a week on etelcalcetide and 0.3 on cinacalcet over 8 weeks (p = 0.27) ⁹. Both trial reports end with the same caution: "Further studies are needed to assess clinical outcomes as well as longer-term efficacy and safety" ⁴, ³. The outcomes the label reports are blood measurements: PTH, calcium and phosphate ¹.

What are the side effects?

The label's side-effect table pools the two placebo-controlled studies: 503 patients on etelcalcetide and 513 on placebo, with a mean exposure to etelcalcetide of 23.6 weeks ¹. These are the patients who received the study drug; 509 and 514 were randomized ¹, ³.

"Blood calcium decreased," a calcium reading without symptoms that was below 7.5 mg/dL or needed treatment, was recorded in 64 percent on etelcalcetide and 10 percent on placebo ¹. Hypocalcemia, here low blood calcium with symptoms, was recorded in 7 percent against 0.2 percent ¹. Muscle spasms occurred in 12 percent against 7, nausea in 11 against 6, diarrhea in 11 against 9, and vomiting in 9 against 5 ¹. Headache occurred in 8 percent against 6, and paresthesia, tingling or numbness, in 6 against 1 ¹.

The label's first warning is hypocalcemia: Parsabiv "lowers serum calcium" and "can lead to hypocalcemia, sometimes severe" ¹. "Significant lowering of serum calcium can cause paresthesias, myalgias, muscle spasms, seizures, QT interval prolongation, and ventricular arrhythmia" ¹. Myalgias are muscle pains, and the last two terms describe a slowed electrical recovery of the heart and a dangerous heart rhythm. In the pooled studies, a QT interval corrected for heart rate (QTcF) above 500 milliseconds was recorded in 4.8 percent on etelcalcetide and 1.9 percent on placebo ¹. The label warns that use with "another oral calcium-sensing receptor agonist could result in severe, life-threatening hypocalcemia" ¹.

Heart failure requiring a hospital stay occurred in 2 percent of etelcalcetide patients and 1 percent of placebo patients ¹. The label says "a causal relationship to PARSABIV could not be completely excluded" ¹.

Two patients on etelcalcetide, in 1,253 patient-years of exposure, had upper gastrointestinal bleeding noted at the time of death ¹. A patient-year is one patient treated for one year. No patient in the control groups did, in 384 patient-years, and the label says there were "too few cases to determine whether these cases were related to PARSABIV" ¹. It also warns that adynamic bone, bone with very low turnover, "may develop if PTH levels are chronically suppressed" ¹.

The label's one contraindication is "known hypersensitivity to etelcalcetide or any of its excipients," its inactive ingredients ¹. It reports that hypersensitivity reactions, "including face edema and anaphylactic reaction, have occurred with PARSABIV" ¹. An anaphylactic reaction is a severe allergic reaction. Reports since approval add seizures secondary to hypocalcemia ¹. They also add hypocalcemia in patients given other calcium-lowering products at the same time, such as cinacalcet or denosumab ¹.

Antibodies to etelcalcetide were found in 71 of 995 patients (7.1 percent) treated for up to 6 months, and 57 of the 71 had them beforehand ¹. The label found no evidence that they altered the drug's blood levels, its effect or its safety ¹.

In the trial against cinacalcet, decreased blood calcium was the most common adverse effect ⁴. It was recorded in 68.9 percent on etelcalcetide and 59.8 percent on cinacalcet ⁴, ⁹.

There are "no available data" on use in pregnant women ¹. The label says use "is not recommended while breastfeeding" ¹.

In sport

WADA's 2026 Prohibited List does not name etelcalcetide ¹⁰. WADA is the World Anti-Doping Agency, and its list groups peptide hormones, growth factors, related substances and mimetics in section S2 ¹⁰. Neither etelcalcetide nor its class, the calcimimetics, appears there or in any other section ¹⁰. One method rule, M2.2, concerns the intravenous route rather than the drug. It prohibits "Intravenous infusions and/or injections of more than a total of 100 mL per 12-hour period except for those legitimately received in the course of hospital treatments, surgical procedures or clinical diagnostic investigations" ¹⁰.

What JumpstartMD offers

JumpstartMD does not prescribe etelcalcetide. Our peptide library covers it so you have the facts on its FDA status and the evidence, current as of November 10, 2026.

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Compounded medications are not FDA-approved, and FDA does not review their safety, effectiveness, or quality before they are marketed. A licensed clinician decides after an evaluation whether a peptide is appropriate for you, and not every patient will qualify.