Rezlidhia is a prescription medicine used to treat adults with acute myeloid leukemia (AML) with a specific gene mutation called IDH1. 

The IDH1 mutation prevents immature blood cells in the bone marrow from developing into healthy mature blood cells.

Rezlidhia contains olutasidenib, which belongs to the class of drugs called isocitrate dehydrogenase-1 (IDH1) inhibitors. It works to treat acute myeloid leukemia by blocking the activity of the protein produced by IDH1.

Your healthcare provider will test you for the IDH1 mutation with an FDA-approved test to make sure that Rezlidhia is right for you.

It is not known if this medicine is safe and effective in children.

What is Rezlidhia used to treat?

Rezlidhia is used to treat acute myeloid leukemia (a fast-growing cancer of the bone marrow and blood cells) with an IDH1 mutation when the disease has relapsed (come back) or is refractory (has stopped responding to treatment).

In acute myeloid leukemia, mutations cause the myeloblasts (immature blood cells that form in the bone marrow) to grow and divide uncontrollably. Mutations in the IDH1 gene can lead to the accumulation of 2-hydroxyglutarate (2-HG). Increased levels of 2-HG interfere with the processes by which immature blood cells become mature cells.

Rezlidhia works to inhibit mutated IDH1 to reduce 2-HG levels and restore normal differentiation of myeloid cells.

Rezlidhia may cause serious side effects including:

Differentiation Syndrome. Differentiation syndrome is a condition that affects your blood cells and may be lifethreatening or lead to death. Differentiation syndrome in adults with acute myeloid leukemia (AML) has occurred as early as 1 day and up to 18 months after starting Rezlidhia. Call your healthcare provider or go to the nearest hospital emergency room right away if you develop any of the following symptoms of differentiation syndrome during treatment:

• fever
• cough
• trouble breathing
• decreased urination
• dizziness or lightheadedness
• weight gain
• swelling of your arms or legs 

If you develop signs and symptoms of differentiation syndrome, your healthcare provider may treat you with a corticosteroid medicine or a medicine called hydroxyurea and may monitor you in the hospital.

See Rezlidhia side effects for more information about side effects.

Take Rezlidhia exactly as your healthcare provider tells you to. Do not change your dose or stop treatment without talking to your healthcare provider.

Take Rezlidhia capsules 2 times a day (about 12 hours apart) around the same times each day.

Take the capsules on an empty stomach, at least 1 hour before or 2 hours after a meal. Swallow the capsules whole. Do not break, open or chew the capsules.

If you vomit after taking a dose, do not take another dose. Take your next dose at your usual time.

If you miss a dose, or did not take it at the usual time, take your dose as soon as possible and at least 8 hours before your next dose. Return to your normal schedule the following day. Do not take 2 doses of Rezlidhia within 8 hours.

Usual Adult Dose for Acute Myeloid Leukemia

150 mg orally twice daily, until disease progression or unacceptable toxicity.

Comments:
-Select patients based on presence of IDH1 mutation(s).
-Take on an empty stomach at least 1 hour before or 2 hours after a meal.

Use:
-Treatment of adult patients with relapsed or refractory acute myeloid leukemia (AML) with a susceptible IDH1 mutation as detected by an FDA-approved test. 

Before you start treatment, tell your healthcare provider about all of your medical conditions, including if you:

• have liver problems
• are pregnant or plan to become pregnant. Rezlidhia may harm your unborn baby.
• are breastfeeding or plan to breastfeed. It is not known if Rezlidhia passes into your breast milk. Do not breastfeed during your treatment, and for 2 weeks after your last dose.

Rezlidhia may cause serious side effects, including:

• See Important information
• Liver problems. Changes in liver function tests are common during treatment with Rezlidhia and can be serious.
  Your healthcare provider will do blood tests to check your liver function before and during treatment. Tell your healthcare provider right away if you develop any of the following symptoms of liver problems during treatment:
  • yellowing of your skin or the white part of your eyes (jaundice)
  • dark "tea-colored" urine
  • loss of appetite
  • pain on the upper right side of your stomach area
  • feeling very tired or weak

The most common side effects include:

• abnormal liver function tests
• nausea
• feeling tired or unwell
• joint pain
• constipation
• shortness of breath
• fever
• rash
• mouth sores
• diarrhea
• changes in certain blood tests

Tell your healthcare provider if you have any nausea, constipation, diarrhea, vomiting, stomach pain or mouth sores.

Your healthcare provider will do blood tests before you start, and during treatment. Your healthcare provider may decrease, temporarily hold, or permanently stop your treatment if you develop certain side effects.

These are not all the possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.

Especially tell your doctor if you take:

• medicines for epilepsy (phenobarbital, carbamazepine, eslicarbazepine, cenobamate, fosphenytoin, oxcarbazepine, phenytoin, primidone);
• medicines containing rifampin;
• medicines containing rifabutin;
• apalutamide, enzalutamide;
• bosentan;
• bexarotene;
• HIV medicines containing efavirenz, etravirine, or nevirapine;
• lorlatinib
• medicines containing elagolix
• medicines containing lumacaftor;
• modafinil, armodafinil;
• nafcillin
• St. John's wort

Know the medicines you take. Keep a list of your medicines with you to show your healthcare provider and pharmacist each time you get a new medicine.