WHY ISTURISA

How Isturisa Works

ISTURISA is a targeted cortisol synthesis inhibitor1,2

It targets the overproduction of cortisol, regardless of the endogenous source, by blocking 11β-hydroxylase, the enzyme central to the process.1-3 The effects of ISTURISA can be reversed or decreased upon treatment discontinuation or dose tapering.1,4

Chart showing ISTURISA Cholesterol Mechanism of Action

Changes in the levels of 11-deoxycortisol and ACTH were dose dependent.1

ACTH, adrenocorticotropic hormone.

Explore Clinical Study Results

References: 1. Isturisa. Package insert. Recordati Rare Diseases Inc; 2025. 2. Bertagna X, Pivonello R, Fleseriu M, et al. LCI699, a potent 11β-hydroxylase inhibitor, normalizes urinary cortisol in patients with Cushing’s disease: results from a multicenter, proof-of-concept study. J Clin Endocrinol Metab. 2014;99(4):1375-1383. doi:10.1210/ jc.2013-2117 3. Perosevic M, Tritos NA. Clinical utility of osilodrostat in Cushing’s disease: review of currently available literature. Drug Des Devel Ther. 2023;17:1303-1312. doi:10.2147/DDDT.S315359 4. 4. Pivonello R, Fleseriu M, Newell-Price J, et al. Efficacy and safety of osilodrostat in patients with Cushing’s disease (LINC 3): a multicentre phase III study with a double-blind, randomised withdrawal phase. Lancet Diabetes Endocrinol. 2020;8(9):748-761. doi:10.1016/S2213-8587(20)30240-0

INDICATIONS AND USAGE

ISTURISA® (osilodrostat) is indicated for the treatment of endogenous hypercortisolemia in adults with Cushing’s syndrome for whom surgery is not an option or has not been curative.

IMPORTANT SAFETY INFORMATION

Hypocortisolism: ISTURISA lowers cortisol levels and can lead to hypocortisolism and sometimes life-threatening adrenal insufficiency. Lowering of cortisol can cause nausea, vomiting, fatigue, abdominal pain, loss of appetite, and dizziness. Significant lowering of serum cortisol may result in hypotension, abnormal electrolyte levels, and hypoglycemia.

Hypocortisolism can occur at any time during ISTURISA treatment. Evaluate patients for precipitating causes of hypocortisolism (infection, physical stress, etc.). Monitor 24-hr urine free cortisol, serum or plasma cortisol, and patient’s signs and symptoms periodically during ISTURISA treatment.

Decrease or temporarily discontinue ISTURISA if urine free cortisol levels fall below the target range, there is a rapid decrease in cortisol levels, and/or patients report symptoms of hypocortisolism. Stop ISTURISA and administer exogenous glucocorticoid replacement therapy if serum or plasma cortisol levels are below target range and patients have symptoms of adrenal insufficiency. After ISTURISA interruption or discontinuation, cortisol suppression may persist beyond the 4-hour half-life of ISTURISA.

Educate patients on the symptoms associated with hypocortisolism and advise them to contact a healthcare provider if they occur.

QTc Prolongation: ISTURISA is associated with a dose-dependent QT interval prolongation which may cause cardiac arrhythmias. Perform an ECG to obtain a baseline QTc interval measurement prior to initiating therapy with ISTURISA and monitor for an effect on the QTc interval thereafter.

Correct hypokalemia and/or hypomagnesemia prior to ISTURISA initiation and monitor periodically during treatment with ISTURISA. Use with caution in patients with risk factors for QT prolongation and consider more frequent ECG monitoring.

Elevations in Adrenal Hormone Precursors and Androgens: ISTURISA blocks cortisol synthesis and may increase circulating levels of cortisol and aldosterone precursors and androgens. This may activate mineralocorticoid receptors and cause hypokalemia, edema and hypertension. Hypokalemia should be corrected prior to initiating ISTURISA. Monitor patients treated with ISTURISA for hypokalemia, worsening of hypertension and edema. Inform patients of the symptoms associated with hyperandrogenism and advise them to contact a healthcare provider if they occur.

The most common adverse reactions (incidence >20%) are adrenal insufficiency, fatigue, nausea, headache, edema, decreased appetite, arthralgia, myalgia, and diarrhea.

To report SUSPECTED ADVERSE REACTIONS, contact Recordati Rare Diseases Inc. at 1-888-575-8344, or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

Drug Interactions:

Use in Specific Populations:

Dosage Interruptions and Modifications: If treatment is interrupted, re-initiate ISTURISA at a lower dose when cortisol levels are within target ranges and patient symptoms have been resolved.

ISTURISA® (osilodrostat) tablets, for oral use, is available as 1 mg and 5 mg tablets.

Please see full Prescribing Information.

Patient portrayal.

Meghan, Actor Portrayal
BASELINE CHARACTERISTICS Age: 34 Race: White Height: 5'6" Weight: 80.1 kg (177 lb) BMI: 28.6 kg/m2
Diagnosis Cushing’s disease: recurrent
Time since diagnosis  6 years
Treatment
  • Transsphenoidal surgery was performed within 2 months of diagnosis 
  • Pituitary radiotherapy was performed 2 years ago
Status
  • In remission, but beginning to develop symptoms of recurrence
Symptoms
  • Weight gain in the abdomen
  • Fatigue and sleep disturbances
  • Anxiety and depression
  • Easy bruising
  • Increased thirst and urination
Comorbidities
  • Depression/anxiety
  • Hyperlipidemia
  • Prediabetes
Vital signs and labs Blood pressure: 124/86 mm Hg HR: 72 bpm Total cholesterol: 213 mg/dL (reference range: <200 mg/dL) LDL: 112 mg/dL (reference range: <100 mg/dL) HDL: 45 mg/dL (reference range: >60 mg/dL) Glucose: 123 mg/dL (reference range: <100 mg/dL) HbA1c: 6.2% (reference range: <5.7%) UFC: 217.5 nmol/24 h (78.8 μg/24 h) (reference range: <145 nmol/24 h [approximately 11-53 μg/24 h]) UFC fold ULN: 1.5 x ULN mUFC

Patient portrayal.

Questions to consider when developing a treatment plan

  1. What would be the consequences if this patient’s cortisol levels remain uncontrolled?
  2. How do you evaluate severity of disease in your patients?
  3. What are your treatment goals for this patient?
  4. What do you consider to be the appropriate next therapy option for this patient?
  5. Would you consider ISTURISA an appropriate option for this patient? Why or why not?

BMI, body mass index; bpm, beats per minute; HbA1c, hemoglobin A1c; HDL, high-density lipoprotein; HR, heart rate; LDL, low-density lipoprotein; mUFC, mean urinary free cortisol; UFC, urinary free cortisol; ULN, upper limit of normal.

Why ISTURISA May be Right for Your Patient

Patient portrayal.

Mike, Actor Portrayal
BASELINE CHARACTERISTICS Age: 34 Race: White Height: 5'10” Weight: 95.9 kg (211 lb) BMI: 30.3 kg/m2
Diagnosis Cushing’s syndrome: treatment naive
Time since diagnosis 7 months
Treatment
  • Exogenous sources of hypercortisolemia were ruled out
  • Standard imaging techniques were unsuccessful in locating the tumor
  • Inferior petrosal sinus sampling indicated an ectopic source
  • Patient is not a candidate for surgical intervention
Status
  • Further imaging investigation is required
  • Patient is experiencing symptoms of hypercortisolemia that may benefit from medication therapy
  • Cardiometabolic parameters are currently not controlled despite lifestyle changes and maximized treatment
Symptoms
  • Weight gain in the abdomen
  • Rounded face
  • Hypertension
  • Diabetes
  • Daytime fatigue and nighttime insomnia
  • Muscle weakness
Comorbidities
  • Hypertension
  • Diabetes
  • Hyperlipidemia
Vital signs and labs Blood pressure: 146/92 mm Hg HR: 68 bpm Total cholesterol: 238 mg/dL (reference range: <200 mg/dL) LDL: 121 mg/dL (reference range: <100 mg/dL) HDL: 42 mg/dL (reference range: >60 mg/dL) Glucose: 136 mg/dL (reference range: <100 mg/dL) HbA1c: 7.6% (reference range: <5.7%) UFC: 304.5 nmol/24 h (110.3 μg/24 h) (reference range: <145 nmol/24 h [approximately 11-53 μg/24 h]) UFC fold ULN: 2.1 x ULN mUFC

Patient portrayal.

Questions to consider when developing a treatment plan

  1. What would be the consequences if this patient’s cortisol levels remain uncontrolled?
  2. What are your treatment goals for this patient?
  3. What do you consider to be the appropriate next therapy option for this patient?
  4. Would you consider ISTURISA an appropriate option for this patient? Why or why not?

BMI, body mass index; bpm, beats per minute; HbA1c, hemoglobin A1c; HDL, high-density lipoprotein; HR, heart rate; LDL, low-density lipoprotein; mUFC, mean urinary free cortisol; UFC, urinary free cortisol; ULN, upper limit of normal.

Why ISTURISA May be Right for Your Patient

Patient portrayal.

Stephanie, Actor Portrayal
BASELINE CHARACTERISTICS Age: 31 Race: African American Height: 5'4” Weight: 75.0 kg (165 lb) BMI: 28.3 kg/m2
Diagnosis High clinical suspicion of hypercortisolemia in Cushing’s syndrome; further testing is required
Time since diagnosis Pending diagnosis
Notes
  • UFC labs were repeated twice over several weeks with consistent findings of elevated cortisol
  • Exogenous sources of hypercortisolemia were ruled out
  • Imaging investigation is required
Treatment
  • None
Status
  • Patient has seen an endocrinologist to discuss lack of symptom relief despite lifestyle modification and reported that symptoms are worsening
Symptoms
  • Weight gain in the abdomen
  • Weight gain in the face
  • Facial plethora
  • Muscle weakness
  • Menstrual irregularities
  • Fatigue and sleep disturbances
  • Anxiety and depression
Comorbidities
  • Diabetes
  • Polycystic ovarian syndrome
Vital signs and labs Blood pressure: 130/84 mm Hg HR: 86 bpm Total cholesterol: 208 mg/dL (reference range: <200 mg/dL) LDL: 106 mg/dL (reference range: <100 mg/dL) HDL: 58 mg/dL (reference range: >60 mg/dL) Glucose: 131 mg/dL (reference range: <100 mg/dL) HbA1c: 7.2% (reference range: <5.7%) UFC: 246.5 nmol/24 h (89.3μg/24 h) (reference range: <145 nmol/24 h [approximately 11-53 μg/24 h]) UFC fold ULN: 1.7 x ULN mUFC

Patient portrayal.

Questions to consider when developing a treatment plan

  1. What symptoms lead you to a high clinical suspicion of hypercortisolemia in Cushing’s syndrome?
  2. What would be the consequences if this patient’s cortisol levels remain uncontrolled?
  3. What are your treatment goals for this patient?

BMI, body mass index; bpm, beats per minute; HbA1c, hemoglobin A1c; HDL, high-density lipoprotein; HR, heart rate; LDL, low-density lipoprotein; mUFC, mean urinary free cortisol; UFC, urinary free cortisol; ULN, upper limit of normal.

Why ISTURISA May be Right for Your Patient