Pasireotide
Somatostatin analog
Also Signifor, Signifor LAR, SOM230, SOM 230, Pasireotide pamoate, Pasireotide diaspartate
- Evidence
- AStrong human evidence
- FDA status
- FDA approvedas of 2026-10-26
- Route
- Injection
- Studies cited
- 1 human0 animal or cell
It is an injection for Cushing's disease, where a pituitary tumor makes too much cortisol. In a trial of 162 people about one in four reached normal levels, and most had high blood sugar.
Sold for
Pasireotide is the first drug approved specifically to treat the pituitary tumor behind Cushing's disease, where earlier drugs block cortisol downstream.
Studies say
In the phase 3 trial about one in four patients at the higher trial dose reached normal cortisol at six months, and most developed high blood sugar, which is an approvable but limited result.
Why grade A. Approval for Cushing's disease rests on a randomized, double-blind phase 3 trial in 162 patients that compared two doses, with normalization of urinary cortisol as the primary endpoint. The trial lacked a placebo arm, which is common in Cushing's because untreated disease is dangerous, and response rates were modest. It is the largest prospective drug trial in the disease. 12
FDA. Approved. Pasireotide is sold as Signifor, a twice-daily subcutaneous injection, for adults with Cushing's disease for whom pituitary surgery is not an option or has not worked. A monthly long-acting form, Signifor LAR, is approved for acromegaly and for Cushing's disease. 2
Written from 2 cited sources. Fact-checked 2026-10-27: 16 claims checked, 0 corrected, 1 sources unreachable. Last refreshed 2026-10-27. Not physician reviewed.
What this means for you
- What people take it for
- Cushing's disease caused by a pituitary tumor
- Can a US doctor prescribe it?
- Yes, FDA approved for Cushing's disease when surgery has not worked or is not possible.
- Properly tested in people?
- Yes, in large controlled trials. The main trial had 162 people.
Evidence checklist
- Randomised controlled trial Randomised double-blind, two doses, no placeboyes
- Human study over 100 people Phase 3, 162 patientsyes
- More than one research group Article does not say who ran the trialno information
- Clinical outcomes, not surrogate markers Surrogate: normal urinary cortisolno
- Human safety data beyond case reports Trial data: 73% had high blood sugar eventsyes
Drawn from the cited studies below. A dash means the sources give no information.
What it is
Pasireotide is a lab-made version of somatostatin. It is a cousin of octreotide and lanreotide. Engineers built it to bind a wider set of somatostatin receptor subtypes. The key difference is strong binding to subtype 5. That is the receptor most common on the pituitary tumors that cause Cushing's disease. Novartis developed the drug. Recordati Rare Diseases now markets it in the United States. 12
Cushing's disease is too much cortisol, caused by a pituitary tumor that makes ACTH. Surgery is the first treatment. But it fails or the disease returns in a substantial minority of patients. Until pasireotide in 2012, those patients had no approved drug that acted on the tumor itself. 1
How it works
Somatostatin receptors come in five subtypes. Octreotide binds mainly subtype 2. That subtype is plentiful on growth hormone tumors but scarce on ACTH tumors. This is why octreotide does little in Cushing's disease. Pasireotide binds subtypes 1, 2, 3 and 5, with the highest affinity for 5. On an ACTH-making tumor, activating subtype 5 suppresses ACTH release. Cortisol falls. In some patients the tumor shrinks. The same broad receptor profile acts on pancreatic cells. It suppresses insulin and the gut hormones that boost it. That is why high blood sugar is the signature side effect. 12
What human research shows
The phase 3 trial randomized 162 adults with persistent, recurrent or newly diagnosed Cushing's disease. None could have surgery. They got one of two doses of pasireotide twice a day, double-blind, for six months. Open-label treatment followed up to twelve months. The main measure was normal 24-hour urinary free cortisol at month 6 without a dose increase. About 15 percent of the lower-dose group met it. In the higher-dose group it was 26 percent. Cortisol fell in most patients even when it did not normalize. Blood pressure, weight, cholesterol and quality of life improved in step. Patients whose cortisol was going to normalize generally showed a drop within the first two months. The authors suggested this could identify non-responders early. 1
In acromegaly, researchers compared the long-acting form with octreotide LAR. It produced biochemical control in a higher share of patients. That is the basis of the approved use as described in the label. 2
| Study | Model | Finding |
|---|---|---|
| Phase 3 Cushing's disease trial (Colao 2012) | Humans, n=162 with Cushing's disease, randomized double-blind two-dose | Urinary free cortisol normalized at six months in about 15 and 26 percent of patients at the two trial doses, with hyperglycemia-related events in 73 percent. 1 |
| Signifor prescribing information | FDA label | Documents the approved indications, glucose monitoring requirements and somatostatin-class warnings. 2 |
Safety
High blood sugar is the dominant problem. In the Cushing's trial, 73 percent of patients had an adverse event linked to it. Many needed new diabetes treatment. Blood sugar rises within days of starting. Otherwise the side effects resemble other somatostatin drugs. They include diarrhea, nausea, belly pain and gallstones. The heart rate can slow, and the QT interval can change. Liver enzymes can rise. The label calls for glucose monitoring before and during treatment. It also calls for periodic gallbladder ultrasound and ECG. 12
Cortisol can fall below normal, especially when pasireotide is combined with other cortisol-lowering drugs. So doctors need to watch for signs of adrenal insufficiency, such as weakness and dizziness. 2
Questions for your clinician
- How will my blood sugar be monitored?
- What is the chance of reaching normal cortisol on this drug?
- Do gallbladder or heart rhythm problems matter for me?
Questions people ask
Why does pasireotide raise blood sugar so much?
It suppresses insulin release from the pancreas. It also blocks GLP-1 and GIP, the gut hormones that stimulate insulin after meals. Octreotide does some of this too. But pasireotide binds more receptors, so the effect is much stronger. Most patients in the trial needed glucose monitoring. Many needed new diabetes drugs. 12
How is it different from octreotide?
Both are somatostatin analogs. But pasireotide binds four receptor subtypes, with strong affinity for subtype 5. That is the one found on ACTH-making pituitary tumors. So it works in Cushing's disease where octreotide does not. The price is worse effects on blood sugar. 1
Does it cure Cushing's disease?
No. It controls cortisol while treatment continues. In a minority of patients it does so fully, and in more it does so partly. Surgery is the only cure. Pasireotide is for people whose surgery has failed or cannot be done. 12
How soon can you tell if it will work?
In the trial, patients who eventually normalized cortisol usually showed a clear fall within the first one to two months. Those with no early response rarely responded later. This helps avoid long exposure to side effects in people it will not help. 1
Citations
- Colao 2012, N Engl J Med: a 12-month phase 3 study of pasireotide in Cushing's disease doi.org
- Recordati Rare Diseases: Signifor (pasireotide) prescribing information recordatirarediseases.com