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

What is pasireotide?

Pasireotide is a prescription drug for two diseases of the pituitary, the hormone gland at the base of the brain ¹, ². It is a somatostatin analog: a drug built to act like somatostatin, a natural hormone ¹. The label describes it as a cyclohexapeptide, a ring of six amino acids, the building blocks of proteins ¹.

It is not a wellness, weight-loss or performance peptide. Its two products, Signifor and Signifor LAR, come from Recordati Rare Diseases, and their labels list only Cushing's disease and acromegaly as uses ¹, ². Signifor is a solution of pasireotide diaspartate, injected under the skin ¹. Signifor LAR is a long-acting release form, pasireotide pamoate, injected into a muscle ².

In Cushing's disease, a pituitary tumor releases ACTH (adrenocorticotropic hormone, also called corticotropin), which drives the body's cortisol too high ⁵, ¹. Signifor's trial tracked blood pressure, weight and waist size among the signs of the disease ¹. The Signifor LAR label ties acromegaly to pituitary tumors that release growth hormone ². One of Signifor LAR's acromegaly trials tracked ring size, a measure of finger thickness, and symptoms such as headache, fatigue, sweating and joint pain ².

The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) says of Cushing's disease: "These pituitary tumors make too much ACTH, causing the adrenals to make too much cortisol" ⁶. Of growth hormone in acromegaly, it says: "In adults, too much of this hormone causes bones, cartilage, body organs, and other tissues to increase in size" ⁷.

Is pasireotide FDA-approved?

Yes, as two prescription drugs. FDA approved Signifor (pasireotide diaspartate) on December 14, 2012, under new drug application (NDA) 200677 ³. It approved Signifor LAR (pasireotide pamoate) on December 15, 2014, under NDA 203255 ⁴. Drugs@FDA lists every strength of both with marketing status "Prescription" as of November 9, 2026, the date of the record's data ³, ⁴.

Signifor's label states one use ¹. It "is indicated for the treatment of adult patients with Cushing's disease for whom pituitary surgery is not an option or has not been curative" ¹.

Signifor LAR's label states two ². The first is "patients with acromegaly who have had an inadequate response to surgery and/or for whom surgery is not an option" ². The second is "patients with Cushing's disease for whom pituitary surgery is not an option or has not been curative" ². FDA added the Cushing's disease use to Signifor LAR on June 29, 2018, through supplement S-004 ⁴. For a reader, that status means pasireotide is an approved prescription product, and its labels state those two uses ¹, ², ³, ⁴.

See the FDA status of every peptide, updated weekly.

How does pasireotide work?

Pasireotide binds to somatostatin receptors, the docking sites on cells that somatostatin itself uses ¹. Five types are known in people, numbered 1 to 5, and the Signifor LAR label says pasireotide "binds with high affinity to 4 of the 5" ². In the labels' binding table, its tightest attachment is to type 5 and its loosest to type 4 ¹, ².

That preference for type 5 matters in Cushing's disease ¹. The Signifor label says the tumor cells of patients with the disease "frequently over-express SSTR5," the type 5 receptor, while the other types are often missing or scarce ¹. When pasireotide activates the receptors, the tumor releases less ACTH, "which leads to decreased cortisol secretion" ¹.

For acromegaly, the Signifor LAR label says binding to types 2 and 5 "may be relevant for inhibition of GH secretion," where GH stands for growth hormone ². In the label's studies of patients, Signifor LAR lowered growth hormone and IGF-1 (insulin-like growth factor 1), the blood tests by which its acromegaly trials defined control ².

The drug's effects are not confined to the pituitary ¹. Signifor's label describes one study in healthy volunteers that was randomized and double-blind: treatment was assigned by chance, and neither volunteers nor staff knew who received what ¹. In it, high blood sugar on pasireotide "was related to significant decreases in insulin secretion as well as incretin hormones" ¹. Incretin hormones are gut hormones that prompt the pancreas to release insulin after a meal. The label names those hormones as GLP-1 (glucagon-like peptide-1) and GIP (glucose-dependent insulinotropic polypeptide), and it ties the finding to its hyperglycemia warning, as a safety matter ¹.

What does the research show?

Pasireotide is approved by FDA for Cushing's disease and acromegaly, and its labels describe four randomized trials in patients ¹, ². Two, in Cushing's disease, compared a lower and a higher dose of Signifor or of Signifor LAR; two, in acromegaly, compared Signifor LAR with another somatostatin analog ¹, ².

Signifor's trial was a phase 3 study, the late-stage kind that precedes an approval, in 162 adults with Cushing's disease ⁵, ¹. Each had urinary free cortisol, the cortisol passed in urine over 24 hours, above 1.5 times the upper limit of normal ¹. They were assigned to a lower or a higher dose injected twice a day, 82 and 80 patients, so both groups took pasireotide ⁵, ¹.

The main test was a normal urinary cortisol at month 6 with no dose increase along the way ¹. Twelve of the 82 patients on the lower dose (15 percent) and 21 of the 80 on the higher dose (26 percent) passed it ⁵, ¹. Median urinary cortisol fell by 47 percent and 46 percent in the two groups ¹. About two-thirds of the patients completed 6 months ¹. The trial was published in March 2012 and funded by Novartis Pharma ⁵.

The same label reports weight. At month 6 the mean falls were 4.4 kilograms in weight, 1.6 kg/m² in body mass index (BMI, weight relative to height) and 2.6 centimeters in waist ¹. It gives those figures for the patients as a whole, not by dose group, and there was no comparison group ¹. Its caution follows: "because of the variability in response and the absence of a control group in this trial, it is uncertain whether these changes could be ascribed to the effects of SIGNIFOR" ¹. These were adults with Cushing's disease, not people seeking weight loss ¹.

Signifor LAR's Cushing's disease trial, a double-blind phase 3 study, randomized 150 patients to a lower or a higher starting dose once every 28 days ². Their urinary cortisol at screening was 1.5 to 5 times the upper limit of normal ². At month 7 it was normal in 29 of 74 patients (39.2 percent) on the lower dose and 31 of 76 (40.8 percent) on the higher ².

The 95 percent confidence intervals, the ranges the true rates plausibly lie in, were 28.0 to 51.2 and 29.7 to 52.7 ². Patients with no month-7 measurement, 17 and 9 in the two groups, were counted as non-responders ². When patients whose dose was raised before month 7 were also counted as non-responders, the rates were 25.7 percent and 31.6 percent ². At month 12 the response rates were 35.1 percent and 25.0 percent ².

In acromegaly, a double-blind trial randomized 358 patients with active disease who had never taken a drug for it ². Half were assigned to Signifor LAR and half to "another somatostatin analog active comparator" ². The comparator was octreotide LAR, another long-acting somatostatin analog ², ⁸. Control meant a mean growth hormone below 2.5 micrograms per liter with a normal IGF-1 at month 12 ².

Control was reached by 31.3 percent of 176 patients on Signifor LAR and 19.2 percent of 182 on the comparator ². The label gives a p-value below 0.01, meaning the gap is unlikely to be chance ². It also notes that the comparator's maximum U.S. dose was not used ². On MRI at month 12, 98 percent of the Signifor LAR patients had a smaller or unchanged tumor ². In the trial report, mean tumor volume fell by 40 percent on Signifor LAR and 38 percent on octreotide LAR by month 12 ⁸.

A second phase 3 trial enrolled 198 patients whose acromegaly was inadequately controlled after at least 6 months on octreotide or lanreotide, two first-generation somatostatin analogs ², ⁹. Sixty-five were assigned to each of two Signifor LAR doses, and 68 continued their earlier drug ², ⁹. Patients and investigators knew who had switched but not which pasireotide dose was given ⁹. At 24 weeks, 15.4 percent and 20.0 percent of the two Signifor LAR groups reached control, against none of the 68 who continued ², ⁹. The trial was published online in September 2014 and funded by Novartis Pharma AG ⁹.

Both labels say safety and effectiveness "have not been established in pediatric patients" ¹, ². As of November 10, 2026, neither label and neither published trial report describes a trial of pasireotide for weight loss, muscle, aging or performance ⁵, ¹, ², ⁹.

What are the side effects?

In Signifor's Cushing's disease trial, adverse reactions were reported in 98 percent of the 162 patients ¹. Serious adverse events were reported in 25 percent, 17 percent left the study because of adverse events, and there were no deaths ¹. The most common reactions were diarrhea (58 percent), nausea (52 percent), hyperglycemia, meaning high blood sugar (40 percent), and cholelithiasis, meaning gallstones (30 percent) ¹. Headache (28 percent) and abdominal pain (24 percent) followed ¹.

On blood sugar, the Signifor label says "nearly all patients in the study, including those with normal glucose status at baseline, pre-diabetes, and diabetes, developed worsening glycemia in the first two weeks of treatment" ¹. Mean fasting glucose rose from 98.6 to 125.1 mg/dL by month 6 in the lower-dose group and from 97.0 to 128.0 in the higher-dose group ¹. HbA1c, a blood test of average sugar over recent months, rose from 5.8 percent to 7.2 percent and from 5.8 percent to 7.3 percent ¹. A month after the drug was stopped, both measures had fallen but "remained above baseline values" ¹. In the published report of the trial, a glucose-lowering medication was started in 74 of the 162 patients ⁵.

With Signifor LAR in acromegaly patients new to drug treatment, hyperglycemia was reported in 29 percent of 178 patients, against 8 percent of 180 on the comparator ². Diabetes mellitus was reported in 26 percent against 4 percent ². Five Signifor LAR patients, two of whom had normal blood sugar at the start, were hospitalized for hyperglycemia, and none on the comparator ². Diarrhea was reported in 39 percent on Signifor LAR against 45 percent on the comparator, and gallstones, new or worsened, in 26 percent against 36 percent ². "Weight decreased" was listed as an adverse reaction in 5 percent of the Signifor LAR group and 4 percent of the comparator group ².

Among acromegaly patients switched from another somatostatin analog, hyperglycemia was reported in 33 percent of 63 on the lower Signifor LAR dose ². It was reported in 30 percent of 62 on the higher dose and 14 percent of the 66 who continued their earlier drug ². Diabetes mellitus was reported in 21, 31 and 9 percent of the three groups ². Signifor LAR's Cushing's disease trial had no comparator drug ². In it, hyperglycemia was reported in 47 percent of 150 patients, diabetes mellitus in 27 percent and gallstones in 33 percent ².

Under "Contraindications," each label reads "None" ¹, ². Both carry warnings on hyperglycemia and diabetes, on bradycardia, a slow heart rate, and on QT prolongation, a change in the heart's electrical timing ¹, ². Both also warn of raised liver tests, gallstones and their complications, and deficiency of other pituitary hormones ¹, ².

Signifor LAR's label says it "can cause increases in blood glucose levels which are sometimes severe" ². It adds: "There have been postmarketing cases of ketoacidosis with SIGNIFOR LAR in patients with history of diabetes and in patients without history of diabetes" ². Ketoacidosis is a buildup of acids called ketones in the blood when the body has too little insulin.

Signifor's label warns of hypocortisolism, cortisol falling too low, with signs such as weakness, fatigue, nausea, vomiting and low blood pressure ¹. Across Signifor's development program, four people had two liver tests, ALT and bilirubin, raised together: one patient with Cushing's disease and three healthy volunteers ¹. All four cases resolved after the drug was stopped ¹. Across its clinical studies, the Signifor LAR label reports a corrected QT interval above 480 milliseconds in 6 patients, and none above 500 ².

Both labels, each revised in July 2024, carry a warning on steatorrhea, fatty stools ¹, ². It says somatostatin analogs "reversibly inhibit secretion of pancreatic enzymes and bile acids, which may result in malabsorption of dietary fats and subsequent symptoms of steatorrhea, loose stools, abdominal bloating, and weight loss" ¹, ². Weight loss appears there as a symptom of poor fat absorption that the label tells clinicians to evaluate, not as a benefit ¹, ².

Signifor's label says the data in pregnant women "are insufficient to inform a drug-associated risk for major birth defects and miscarriage" ¹. It tells clinicians to discuss "the potential for unintended pregnancy with premenopausal women," because lower cortisol "may lead to improved fertility" ¹. It also says to "avoid the use of SIGNIFOR in patients with severe hepatic impairment," meaning severe liver disease ¹. Signifor LAR's label carries the same pregnancy statement and says to "avoid use in patients with severe hepatic impairment"; it covers adrenal insufficiency under its pituitary-hormone warning ².

In sport

Pasireotide is not named on WADA's 2026 Prohibited List, and the list does not name somatostatin analogs as a class ¹⁰. WADA is the World Anti-Doping Agency. Section S2 of its list, on peptide hormones, names growth hormone with its analogs, fragments and releasing factors, and corticotropins, the hormone family ACTH belongs to ¹⁰.

What JumpstartMD offers

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

Ready to talk?

Book FREE Consultation

Share your details and a JumpstartMD team member will reach out shortly. Or call 408.478.3496 for your free, no-obligation consultation.

Share your details and a JumpstartMD team member will reach out when we open.

Disclaimer

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.