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Medically reviewed on Nov 15, 2018


(vor IN oh stat)

Index Terms

  • SAHA
  • Suberoylanilide Hydroxamic Acid

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling.

Capsule, Oral:

Zolinza: 100 mg

Brand Names: U.S.

  • Zolinza

Pharmacologic Category

  • Antineoplastic Agent, Histone Deacetylase (HDAC) Inhibitor


Inhibits histone deacetylase enzymes, HDAC1, HDAC2, HDAC3, and HDAC6, which catalyze acetyl group removal from protein lysine residues (including histones and transcription factors). Histone deacetylase inhibition results in accumulation of acetyl groups, which alters chromatin structure and transcription factor activation; cell growth is terminated and apoptosis occurs.


Glucuronidated and hydrolyzed (followed by beta-oxidation) to inactive metabolites


Urine: 52% (~52% as inactive metabolites; <1% as unchanged drug)

Time to Peak

Plasma: With high-fat meal: ~4 hours (range: 2 to 10 hours)

Half-Life Elimination

~2 hours

Protein Binding


Special Populations: Hepatic Function Impairment

In a pharmacokinetic study in cancers other than cutaneous T-cell lymphoma, the AUC was increased 50% in patients with mild and moderate impairment, and increased 66% in patients with severe impairment, compared to patients with normal hepatic function.

Use: Labeled Indications

Cutaneous T-cell lymphoma: Treatment of cutaneous manifestations of cutaneous T-cell lymphoma (CTCL) with progressive, persistent, or recurrent disease on or following 2 systemic treatments


There are no contraindications in the manufacturer’s U.S. labeling.

Canadian labeling: Hypersensitivity to vorinostat or any component of the formulation; severe hepatic impairment (total bilirubin ≥3 times ULN)

Dosing: Adult

Cutaneous T-cell lymphoma (CTCL): Oral: 400 mg once daily until disease progression or unacceptable toxicity

Dosing: Geriatric

Refer to adult dosing.

Dosing: Renal Impairment

There are no dosage adjustments provided in the manufacturer's labeling (has not been studied). However, based on the minimal renal elimination, adjustment not expected. Use with caution.

Dosing: Hepatic Impairment

U.S. labeling: Initial:

Mild-to-moderate impairment (total bilirubin 1-3 times ULN or AST >ULN): 300 mg once daily

Severe impairment (total bilirubin >3 times ULN): There are no dosage adjustments provided in the manufacturer’s labeling (evidence is insufficient for a starting dose recommendation). Doses of 100 to 200 mg once daily were studied in a limited number of patients with severe impairment (Ramalingam, 2010); according to the manufacturer, the maximum dose used was 200 mg once daily.

Canadian labeling:

Mild impairment (total bilirubin >1 to 1.5 times ULN or total bilirubin ≤ULN and AST >ULN): 300 mg once daily

Moderate impairment (total bilirubin 1.5-3 times ULN): Use is not recommended

Severe impairment (total bilirubin ≥3 times ULN): Use is contraindicated

Dosing: Adjustment for Toxicity

U.S. labeling: Intolerance: Reduce dose to 300 mg once daily; if needed, may further reduce to 300 mg daily for 5 consecutive days per week

Canadian labeling: Grade 3 or 4 toxicity: Interrupt therapy until resolves to ≤grade 1 (excluding grade 3 anemia and thrombocytopenia). Upon recovery, may reduce dose to 300 mg once daily. If necessary, may further reduce dose to 300 mg once daily for 5 consecutive days per week.

Additionally, in clinical trials, dose reductions were instituted for the following adverse events: Increased serum creatinine, decreased appetite, hypokalemia, leukopenia, nausea, neutropenia, thrombocytopenia, and vomiting. Vorinostat was discontinued for the following adverse events: Anemia, angioneurotic edema, weakness, chest pain, exfoliative dermatitis, DVT, ischemic stroke, lethargy, pulmonary embolism, and spinal cord injury.

Treatment was withheld in clinical trials for grade 4 anemia or thrombocytopenia or other grade 3 or 4 drug related toxicity, until resolved to ≤grade 1. Treatment was reinitiated with dose reduction (Olsen, 2007).

Extemporaneously Prepared

Although not recommended by the manufacturer, a 50 mg/mL oral suspension may be prepared with capsules. Add 20 mL Ora-Plus® into a glass bottle (≥4 oz). Add the contents of twenty 100 mg capsules and shake thoroughly to disperse (may take up to 3 minutes). Add 20 mL Ora-Sweet® and shake to disperse. Label “shake well”. Stable for 14 days at room temperature.

Fouladi M, Park JR, Stewart CF, et al, "Pediatric Phase I Trial and Pharmacokinetic Study of Vorinostat: A Children's Oncology Group Phase I Consortium Report," J Clin Oncol, 2010, 28(22):3623-9.20606092


Administer with food. Do not open, crush, break, or chew capsules. Avoid direct skin or mucous membrane contact with crushed or broken capsules and/or capsule contents. Maintain adequate hydration (≥2 L/day fluids) during treatment.


Store at 20°C to 25°C (68°F to 77°F); excursions permitted to 15°C to 30°C (59°F to 86°F).

Drug Interactions

Antidiabetic Agents: Hyperglycemia-Associated Agents may diminish the therapeutic effect of Antidiabetic Agents. Monitor therapy

BCG (Intravesical): Myelosuppressive Agents may diminish the therapeutic effect of BCG (Intravesical). Avoid combination

Chloramphenicol (Ophthalmic): May enhance the adverse/toxic effect of Myelosuppressive Agents. Monitor therapy

CloZAPine: Myelosuppressive Agents may enhance the adverse/toxic effect of CloZAPine. Specifically, the risk for neutropenia may be increased. Monitor therapy

Deferiprone: Myelosuppressive Agents may enhance the neutropenic effect of Deferiprone. Avoid combination

Dipyrone: May enhance the adverse/toxic effect of Myelosuppressive Agents. Specifically, the risk for agranulocytosis and pancytopenia may be increased Avoid combination

Promazine: May enhance the myelosuppressive effect of Myelosuppressive Agents. Monitor therapy

QT-prolonging Agents (Highest Risk): QT-prolonging Agents (Indeterminate Risk - Caution) may enhance the QTc-prolonging effect of QT-prolonging Agents (Highest Risk). Management: Monitor for QTc interval prolongation and ventricular arrhythmias when these agents are combined. Patients with additional risk factors for QTc prolongation may be at even higher risk. Monitor therapy

Valproate Products: May enhance the thrombocytopenic effect of Vorinostat. This may increase the risk of gastrointestinal bleeding. Monitor therapy

Vitamin K Antagonists (eg, warfarin): Vorinostat may enhance the anticoagulant effect of Vitamin K Antagonists. Monitor therapy

Adverse Reactions


Cardiovascular: Peripheral edema (13%)

Central nervous system: Fatigue (52%), chills (16%), dizziness (15%), headache (12%)

Dermatologic: Alopecia (19%), pruritus (12%)

Endocrine & metabolic: Hyperglycemia (8% to 69%; grade 3: 5%), weight loss (21%), dehydration (1% to 16%)

Gastrointestinal: Diarrhea (52%), nausea (41%), dysgeusia (28%), anorexia (24%), xerostomia (16%), constipation (15%), vomiting (15%), decreased appetite (14%)

Genitourinary: Proteinuria (51%)

Hematologic & oncologic: Thrombocytopenia (26%; grades 3/4: 6%), anemia (14%; grades 3/4: 2%)

Neuromuscular & skeletal: Muscle spasm (20%)

Renal: Increased serum creatinine (16% to 47%)

Respiratory: Cough (11%), upper respiratory tract infection (11%)

Miscellaneous: Fever (11%)

1% to 10%:

Cardiovascular: Pulmonary embolism (5%), prolonged Q-T interval on ECG (3% to 4%)

Hematologic & oncologic: Squamous cell carcinoma of skin (4%)

<1%, postmarketing, and/or case reports: Abdominal pain, acute ischemic stroke, angioedema, bacteremia (streptococcal), blurred vision, chest pain, cholecystitis, deafness, deep vein thrombosis, diverticulitis, dysphagia, exfoliative dermatitis, gastrointestinal hemorrhage, Guillain-Barre syndrome, hemoptysis, hypertension, hypokalemia, hyponatremia, infection, infection due to enterococcus, lethargy, leukopenia, myocardial infarction, neutropenia, pneumonia, renal failure, sepsis, spinal cord injury, syncope, T-cell lymphoma, tumor hemorrhage, ureteral obstruction, obstructive uropathy (ureteropelvic junction), urinary retention, vasculitis, weakness


Concerns related to adverse effects:

• Bone marrow suppression: Dose-related anemia and thrombocytopenia may occur; may require dosage reduction or discontinuation. Monitor blood counts (every 2 weeks for 2 months, then monthly). Gastrointestinal bleeding due to severe thrombocytopenia has been reported in patients receiving vorinostat in combination with other histone deacetylase inhibitors (eg, valproic acid); monitor platelet counts more frequently in patients receiving concomitant histone deacetylase inhibitor therapy.

• CNS effects: May cause dizziness or fatigue; caution patients about performing tasks which require mental alertness (eg, operating machinery or driving).

• Gastrointestinal toxicities: Nausea, vomiting, and diarrhea may occur; antiemetics and antidiarrheals may be required. Replace fluids and electrolytes to avoid dehydration. Control preexisting nausea, vomiting, and diarrhea prior to treatment initiation. Adverse anastomotic healing events have occurred in patients recovering from bowel surgery; use with caution in the perioperative period in patients requiring bowel surgery.

• Hyperglycemia: May cause hyperglycemia (may be severe). Use with caution in patients with diabetes mellitus; monitor serum glucose every 2 weeks for 2 months, then monthly, or as clinically necessary; may require diet and/or therapy modifications.

• QTc prolongation: QTc prolongation has been observed. Correct electrolyte abnormalities prior to treatment and monitor and correct potassium, calcium, and magnesium levels during therapy. Use caution in patients with a history of QTc prolongation or with medications known to prolong the QT interval. Baseline and periodic ECGs were done in clinical trials (Duvic, 2007; Olsen, 2007).

• Thromboembolic events: Pulmonary embolism and deep vein thrombosis (DVT) have been reported; monitor for signs/symptoms. Use with caution in patients with a history of thrombotic events.

Disease-related issues:

• Hepatic impairment: Use with caution in patients with hepatic impairment; dose reductions are recommended (elimination is predominantly hepatic). The Canadian labeling does not recommend use in patients with moderate hepatic impairment (total bilirubin 1.5 to 3 times ULN) and contraindicates use in severe hepatic impairment (bilirubin ≥3 times ULN).

Concurrent drug therapy issues:

• Drug-drug interactions: Potentially significant interactions may exist, requiring dose or frequency adjustment, additional monitoring, and/or selection of alternative therapy. Consult drug interactions database for more detailed information.

Monitoring Parameters

CBC with differential and serum chemistries, including calcium, magnesium, potassium, glucose and creatinine (baseline, then every 2 weeks for 2 months, then monthly, or as clinically necessary), hepatic function, INR (if on concomitant warfarin therapy), fluid status, signs/symptoms of thromboembolism. Baseline and periodic ECGs were done in clinical trials (and are recommended in the Canadian labeling).

Pregnancy Risk Factor


Pregnancy Considerations

Adverse events were observed in animal reproduction studies. Based on the mechanism of action, may cause fetal harm if administered during pregnancy. Inform patient of potential hazard if used during pregnancy or if pregnancy occurs during treatment.

Patient Education

• Discuss specific use of drug and side effects with patient as it relates to treatment. (HCAHPS: During this hospital stay, were you given any medicine that you had not taken before? Before giving you any new medicine, how often did hospital staff tell you what the medicine was for? How often did hospital staff describe possible side effects in a way you could understand?)

• Patient may experience headache, chills, cough, muscle spasms, lack of appetite, weight loss, constipation, change in taste, hair loss, or signs of common cold. Have patient report immediately to prescriber signs of high blood sugar (confusion, feeling sleepy, more thirst, hunger, passing urine more often, flushing, fast breathing, or breath that smells like fruit), signs of DVT (edema, warmth, numbness, change in color, or pain in the extremities), shortness of breath, angina, tachycardia, severe dizziness, passing out, coughing up blood, sweating a lot, severe nausea, severe vomiting, severe diarrhea, black, tarry, or bloody stools, bruising, bleeding, pale skin, dry mouth, or fatigue (HCAHPS).

• Educate patient about signs of a significant reaction (eg, wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat). Note: This is not a comprehensive list of all side effects. Patient should consult prescriber for additional questions.

Intended Use and Disclaimer: Should not be printed and given to patients. This information is intended to serve as a concise initial reference for health care professionals to use when discussing medications with a patient. You must ultimately rely on your own discretion, experience, and judgment in diagnosing, treating, and advising patients.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.