istodax

Istodax (romidepsin) blocks certain enzymes in the body and interferes with the growth of tumor cells.

Istodax is used to treat T-cell lymphoma affecting the skin (cutaneous T-cell lymphoma, or CTCL). It is usually given after other medicines have been tried without successful treatment of symptoms.

Istodax may also be used for purposes not listed in this medication guide.

Important information

Before you receive Istodax, tell your doctor if you have an electrolyte imbalance, a personal or family history of "Long QT syndrome," heart disease, kidney disease, or liver disease.

Do not receive Istodax if you are pregnant. It could harm the unborn baby. Use effective birth control, and tell your doctor if you become pregnant during treatment. Hormonal forms of contraception (such as birth control pills, injections, implants, skin patches, and vaginal rings) may not be effective enough to prevent pregnancy during your treatment. Ask your doctor about using a non-hormone method of birth control (such as a condom, diaphragm, spermicide) to prevent pregnancy while taking Istodax.

Before receiving Istodax

You should not use Istodax if you are allergic to romidepsin.

To make sure Istodax is safe for you, tell your doctor if you have:

• heart disease, heart rhythm disorder;

• a personal or family history of long QT syndrome;

• liver or kidney disease;

• an electrolyte imbalance (such as high or low levels of potassium or magnesium in your blood); or

• if you are sick with nausea, vomiting, or diarrhea.

FDA pregnancy category D. Do not use Istodax if you are pregnant. It could harm the unborn baby. Use effective birth control, and tell your doctor if you become pregnant during treatment.

See also: Pregnancy and breastfeeding warnings (in more detail)

It is not known whether romidepsin passes into breast milk or if it could harm a nursing baby. You should not breast-feed while using this medicine.

How is Istodax given?

Istodax is injected into a vein through an IV. A healthcare provider will give you this injection. The medicine must be given slowly through an IV infusion, and can take up to 4 hours to complete.

You may be given other medication to prevent nausea or vomiting while you are receiving Istodax.

Istodax is usually given every 7 days for 3 weeks. This treatment cycle may be repeated 28 days after your first dose. Your doctor will determine how long to treat you with Istodax.

Istodax can lower blood cells that help your body fight infections and help your blood to clot. Your blood will need to be tested often. Your cancer treatments may be delayed based on the results of these tests.

Your heart function may also need to be checked using an electrocardiograph or ECG (sometimes called an EKG).

If you have ever had hepatitis B, Istodax can cause this condition to come back or get worse. You will need frequent blood tests to check your liver function during treatment and for several months after you stop using this medicine.

Istodax dosing information

Usual Adult Dose for Cutaneous T-cell Lymphoma:

Recommended dose: 14 mg/m2 administered intravenously over a 4 hour period on days 1, 8, and 15 of a 28 day cycle.

Cycles should be repeated every 28 days provided that the patient continues to benefit from and tolerates the therapy.

Usual Adult Dose for Peripheral T-cell Lymphoma:

Recommended dose: 14 mg/m2 administered intravenously over a 4 hour period on days 1, 8, and 15 of a 28 day cycle.

Cycles should be repeated every 28 days provided that the patient continues to benefit from and tolerates the therapy.

What happens if I miss a dose?

Call your doctor for instructions if you miss an appointment for your Istodax injection.

What happens if I overdose?

Seek emergency medical attention if you think you have used too much of this medicine.

What should I avoid while receiving Istodax?

This medicine can pass into body fluids (including urine, feces, vomit, semen, vaginal fluid). For at least 48 hours after you receive a dose, avoid allowing your body fluids to come into contact with your hands or other surfaces. Patients and caregivers should wear rubber gloves while cleaning up body fluids, handling contaminated trash or laundry or changing diapers. Wash hands before and after removing gloves. Wash soiled clothing and linens separately from other laundry.

Body fluids should not be handled by a woman who is pregnant or who may become pregnant. Use condoms during sexual activity to avoid exposure to body fluids.

Istodax side effects

Get emergency medical help if you have any of these signs of an allergic reaction to Istodax: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Serious and sometimes fatal infections may occur during treatment and within 30 days after treatment with romidepsin. Call your doctor right away if you have signs of infection such as:

• fever, chills, cold or flu symptoms;

• rapid heart rate, rapid and shallow breathing, feeling like you might pass out;

• stabbing chest pain, wheezing, cough with yellow or green mucus;

• swollen gums, painful mouth sores, muscle pain, feeling very tired; or

• upper stomach pain, loss of appetite, dark urine, jaundice (yellowing of the skin or eyes).

• worsening of CTCL skin symptoms;

• pain or burning when you urinate;

• chest pain, feeling short of breath;

• low platelets - easy bruising, unusual bleeding (nose, mouth, vagina, or rectum), purple or red pinpoint spots under your skin;

• low red blood cells - pale skin, feeling light-headed or short of breath, trouble concentrating;

• signs of tumor cell breakdown - lower back pain, blood in your urine, little or no urinating; numbness or tingly feeling around your mouth; muscle weakness or tightness; fast or slow heart rate, weak pulse; confusion, fainting; or

• symptoms of a serious heart rhythm problem - headache with chest pain and severe dizziness, fainting, fast or pounding heartbeats.

Common Istodax side effects may include:

• nausea, vomiting, loss of appetite; or

• mild tired feeling.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

See also: Side effects (in more detail)

What other drugs will affect Istodax?

Tell your doctor about all medicines you use, and those you start or stop using during your treatment with Istodax, especially:

• dexamethasone;

• a blood thinner (warfarin, Coumadin, Jantoven);

• St. John"s wort;

• an antibiotic - clarithromycin, telithromycin; antifungal medication - itraconazole, ketoconazole, voriconazole;

• an antidepressant - citalopram, nefazodone; seizure medicine - carbamazepine, phenobarbital, phenytoin;

• heart rhythm medicine - amiodarone, disopyramide, dofetilide, flecainide, ibutilide, procainamide, quinidine, sotalol; or

• HIV/AIDS medicine - atazanavir, delavirdine, indinavir, nelfinavir, ritonavir, saquinavir; medicine to treat tuberculosis - isoniazid, rifampin.

This list is not complete. Other drugs may interact with romidepsin, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide.