Tazemetostat Side Effects

Medically reviewed by Drugs.com. Last updated on Jan 28, 2025.

Applies to tazemetostat: oral tablet.

Precautions

It is very important that your doctor check your progress at regular visits to make sure that this medicine is working properly. Blood tests may be needed to check for unwanted effects.

Using this medicine while you are pregnant can harm your unborn baby. If you are a woman who can bear children, your doctor may give you a pregnancy test before you start using this medicine to make sure you are not pregnant. Birth control pills may not work as well while you are using this medicine. Use an effective form of birth control (eg, condoms) to keep from getting pregnant during treatment and for at least 6 months after your last dose. Males who are taking this medicine, with female partners who can become pregnant must use effective birth control during and for at least 3 months after the last dose of this medicine. If you think you have become pregnant while using the medicine, tell your doctor right away.

This medicine may increase your chances of having other cancers (eg, leukemia, lymphoma, myelodysplastic syndrome). Discuss these possible effects with your doctor.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal (eg, St. John's wort) or vitamin supplements.

Serious side effects of tazemetostat

Along with its needed effects, tazemetostat may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking tazemetostat:

Other side effects of tazemetostat

Some side effects of tazemetostat may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

For healthcare professionals

Applies to tazemetostat: oral tablet.

General adverse events

The most common adverse reactions (20% or greater) were pain, musculoskeletal pain, abdominal pain, fatigue, nausea, decreased appetite, vomiting, upper respiratory tract infection, and constipation.^[Ref]

Dermatologic

• Very common (10% or more): Alopecia (17%), rash (15%)
• Common (1% to 10%): Herpes zoster^[Ref]

Gastrointestinal

• Very common (10% or more): Nausea (36%), vomiting (24%), constipation (21%), diarrhea (16%), abdominal pain (e.g., abdominal discomfort, abdominal pain, abdominal pain lower, abdominal pain upper) (13%)^[Ref]

Genitourinary

• Very common (10% or more): Urinary tract infection (e.g., cystitis, urinary tract infection, urinary tract infection staphylococcal) (11%)^[Ref]

Hematologic

• Very common (10% or more): Hemoglobin decreased (49%), decreased lymphocytes (36%), white blood cell count decreased (19%), hemorrhage (e.g., wound hemorrhage, rectal hemorrhage, pulmonary hemorrhage, hemorrhage intracranial, cerebral hemorrhage, hemoptysis) (18%), anemia (16%), partial thromboplastin time increased (15%)^[Ref]

Hepatic

• Very common (10% or more): Aspartate aminotransferase increased (18%), alanine aminotransferase increased (14%)^[Ref]

Metabolic

• Very common (10% or more): Triglycerides increased (36%), glucose increased (33%), sodium decreased (30%), phosphate decreased (28%), anorexia (26%), albumin decreased (23%), alkaline phosphatase increased (23%), potassium decreased (20%), weight loss (16%), calcium decreased (16%), glucose decreased (16%), potassium increased (12%), decreased appetite (26%)^[Ref]

Musculoskeletal

• Very common (10% or more): Musculoskeletal pain (e.g., back pain, limb discomfort, musculoskeletal chest pain, musculoskeletal discomfort, musculoskeletal pain, myalgia, neck pain, non-cardiac chest pain, pain in extremity, pain in jaw, spinal pain) (22%)^[Ref]

Nervous system

• Very common (10% or more): Headache (e.g., headache, migraine, sinus headache) (18%)^[Ref]

Oncologic

• Uncommon (0.1% to 1%): Secondary malignancies (e.g., myelodysplastic syndrome [MDS], acute myeloid leukemia [AML])^[Ref]

Other

• Very common (10% or more): Pain (e.g., tumor pain, pain in extremity, non-cardiac chest pain, flank pain, back pain, arthralgia, bone pain, cancer pain, musculoskeletal pain, myalgia, neck pain) (52%), fatigue/asthenia (47%), pyrexia (10%)
• Common (1% to 10%): Sepsis^[Ref]

Renal

• Very common (10% or more): Creatinine increased (14%)^[Ref]

Respiratory

• Very common (10% or more): Cough/productive cough (18%), dyspnea/dyspnea exertional (16%), upper respiratory tract infection (e.g., laryngitis, nasopharyngitis, pharyngitis, rhinitis, sinusitis, upper respiratory tract infection, viral upper respiratory tract infection) (30%), lower respiratory tract infection (e.g., bronchitis, lower respiratory tract infection, tracheobronchitis) (17%)
• Common (1% to 10%): Pneumonia^[Ref]

See also:

Further information

Tazemetostat side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Note: Medication side effects may be underreported. If you are experiencing side effects that are not listed, submit a report to the FDA by following this guide.

Medical Disclaimer