Classification: Histone Deacetylase Inhibitor
About: Vorinostat (Zolinza®)
Vorinostat is in a class of anti-cancer therapies called histone deacetylase (HDAC) inhibitors. Histone deacetylation is a biochemical process that is thought to play a role in promoting tumor growth. It does this by silencing some tumor suppressor genes, as well as other genes that are responsible for cell cycle progression, cell proliferation, programmed cell death (apoptosis), and differentiation (transformation of young cells into specialized cells). Thus, blocking histone deacetylation may allow the body to block this tumor growth and prevent progression.
How to Take Vorinostat
Vorinostat is a capsule to take orally (by mouth) and should be taken with food. The capsules should be swallowed whole; do not break or chew them. The actual dose you are prescribed is dependent upon tolerance of the medication and kidney function.
It is important to make sure you are taking the correct amount of medication every time. Before every dose, check that what you are taking matches what you have been prescribed.
Vorinostat taken in combination with certain anticoagulants (ex. Coumadin) can increase your INR, which is a measure of your blood’s ability to clot. You should have your INR monitored more frequently while on this medication. This medication can also lead to low platelet counts and bleeding if taken with similar medications, including valproic acid. Your platelet counts will also be monitored while you are taking this medication. This medication can also interact with other medications and cause a heart problem called QT prolongation. These medications include: evofloxacin, azithromycin, sulfamethoxazole/trimethoprim, ondansetron, trazodone, quetiapine, citalopram, fluoxetine, amiodarone and methadone. Make sure that your provider is aware of all medications and supplements you take prior to starting treatment with vorinostat.
Storage and Handling
Store your medication in the original, labeled container at room temperature and in a dry location (unless otherwise directed by your healthcare provider or pharmacist). This medication should not be stored in a pillbox. Keep containers out of reach of children and pets.
If a caregiver prepares your dose for you, they should consider wearing gloves or pour the pills directly from their container into the cap, a small cup, or directly into your hand. They should avoid touching the pills. They should always wash their hands before and after giving you the medication. Pregnant or nursing women should not prepare the dose for you. Ask your oncology team where to return any unused medication for disposal. Do not flush down the toilet or throw in the trash.
Where do I get this medication?
Certain cancer medications are only available through specialty pharmacies. If you need to get this medication through a specialty pharmacy, your provider will help you start this process. Where you can fill your prescriptions may also be influenced by your prescription drug coverage. Ask your health care provider or pharmacist for assistance in identifying where you can get this medication.
This medication may be covered under your prescription drug plan. Patient assistance may be available to qualifying individuals without prescription drug coverage. Co-pay cards, which reduce the patient co-pay responsibility for eligible commercially (non-government sponsored) insured patients, may also be available. Your care team can help you find these resources, if they are available.
Possible Side Effects of Vorinostat
There are a number of things you can do to manage the side effects of vorinostat. Talk to your care team about these recommendations. They can help you decide what will work best for you. These are some of the most common or important side effects:
Diarrhea is a potentially dangerous side effect because it can lead to serious dehydration. Diarrhea can be defined as an increase in the number of bowel movements you have in a day. Notify your healthcare team if you develop diarrhea so they can help you manage this side effect. Drink 2 liters of on non-alcoholic, un-caffeinated fluid a day to help prevent dehydration.
Your oncology team can recommend medications to relieve diarrhea. You may need IV fluids and/or electrolytes to prevent or treat dehydration during treatment. Also, try eating low-fiber, bland foods, such as white rice and boiled or baked chicken. Avoid raw fruits, vegetables, whole grain breads, cereals and seeds. Soluble fiber is found in some foods and absorbs fluid, which can help relieve diarrhea. Foods high in soluble fiber include: applesauce, bananas (ripe), canned fruit, orange sections, boiled potatoes, white rice, products made with white flour, oatmeal, cream of rice, cream of wheat, and farina.
Fatigue is very common during cancer treatment and is an overwhelming feeling of exhaustion that is not usually relieved by rest. While on cancer treatment, and for a period after, you may need to adjust your schedule to manage fatigue. Plan times to rest during the day and conserve energy for more important activities. Exercise can help combat fatigue; a simple daily walk with a friend can help. Talk to your healthcare team for helpful tips on dealing with this side effect.
Nausea and/or Vomiting
Talk to your doctor or nurse so they can prescribe medications to help you manage nausea and vomiting. In addition, dietary changes may help. Avoid things that may worsen the symptoms, such as heavy or greasy/fatty, spicy or acidic foods (lemons, tomatoes, oranges). Try antacids, (e.g. milk of magnesia, calcium tablets such as Tums), saltines, or ginger ale to lessen symptoms.
Call your doctor or nurse if you are unable to keep fluids down for more than 12 hours or if you feel lightheaded or dizzy at any time.
Low Platelet Count (Thrombocytopenia)
Platelets help your blood clot, so when the count is low you are at a higher risk of bleeding. Let your oncology care team know if you have any excess bruising or bleeding, including nose bleeds, bleeding gums or blood in your urine or stool. If the platelet count becomes too low, you may receive a transfusion of platelets.
- Do not use a razor (an electric razor is fine).
- Avoid contact sports and activities that can result in injury or bleeding.
- Do not take aspirin (salicylic acid), non-steroidal, anti-inflammatory medications (NSAIDs) such as Motrin/Advil (ibuprofen), Aleve (naproxen), Celebrex (celecoxib) etc. as these can all increase the risk of bleeding. Please consult with your healthcare team regarding use of these agents and all over the counter medications/supplements while on therapy.
- Do not floss or use toothpicks and use a soft-bristle toothbrush to brush your teeth.
Decrease in Appetite and Taste Changes
Nutrition is an important part of your care. Cancer treatment can affect your appetite and, in some cases, the side effects of treatment can make eating difficult. Ask your oncology care team about nutritional counseling services at your treatment center to help with food choices.
- Try to eat five or six small meals or snacks throughout the day, instead of 3 larger meals.
- If you are not eating enough, nutritional supplements may help.
- You may experience a metallic taste or find that food has no taste at all. You may dislike foods or beverages that you liked before receiving cancer treatment. These symptoms can last for several months or longer after treatment ends.
- Avoid any food that you think smells or tastes bad. If red meat is a problem, eat chicken, turkey, eggs, dairy products and fish without a strong smell. Sometimes cold food has less of an odor.
- Add extra flavor to meat or fish by marinating it in sweet juices, sweet and sour sauce or dressings. Use seasonings like basil, oregano or rosemary to add flavor. Bacon, ham and onion can add flavor to vegetables.
Less common, but important side effects can include:
- Blood Clots: Blood clots are a rare side effect of vorinostat that can occur anywhere in the body. They occur most frequently in the calves (legs) or the lungs. People at increased risk for developing blood clots include those with a family history of blood clots, smokers, those who have an inactive lifestyle, older age, and those with other medical problems. Signs of a blood clot in the leg may include any of the following: leg pain, warmth, swelling of one leg more than the other. Signs of a blood clot in the lung could include: fever, shortness of breath that comes on very quickly, racing heart, chest pain (that tends to be worse when you take a deep breath). If you experience symptoms of these problems, you should contact your healthcare provider immediately or go to an emergency room.
- Anemia: Your red blood cells are responsible for carrying oxygen to the tissues in your body. When the red blood cell count is low, you may feel tired or weak. You should let your oncology care team know if you experience any shortness of breath, difficulty breathing or pain in your chest. If the count gets too low, you may receive a blood transfusion.
- High Blood Sugar: This medication can cause elevated blood sugar levels in patients with and without diabetes. If you are a diabetic, you may need to temporarily increase the amount of medication and insulin you are taking to control your diabetes. Your healthcare team will monitor your blood sugar as needed. If you develop increased thirst, urination or hunger, blurry vision, headaches or your breath smells like fruit, notify your healthcare team. Diabetics should monitor their blood sugar closely and report elevations to the healthcare team.
- Laboratory Changes: While taking vorinostat, the levels of electrolytes (potassium, magnesium and calcium), platelets and red blood cells in your blood can become low. You may require transfusions of blood products and electrolytes during treatment with vorinostat. Your healthcare team will monitor your blood counts and electrolytes before and during therapy.
Exposure of an unborn child to this medication could cause birth defects, so you should not become pregnant or father a child while on this medication. Effective birth control is necessary during treatment. Females should use contraception during treatment and for at least 6 months after the last dose. Males with female sexual partners should use contraception during treatment and for at least 3 months after the last dose. Even if your menstrual cycle stops or you believe you are not producing sperm, you could still be fertile and conceive. You should consult with your healthcare team before breastfeeding while receiving this medication.