Olutasidenib

Relapsed or Refractory Acute Myeloid Leukemia REZLIDHIA is indicated for the treatment of adult patients with relapsed or refractory acute myeloid leukemia (AML) with a susceptible isocitrate dehydrogenase-1 (IDH1) mutation as detected by an FDA-approved test [see Dosage and Administration ( 2.1 ), Clinical Pharmacology ( 12.1 ), and Clinical Studies ( 14.1 )] . REZLIDHIA is an isocitrate dehydrogenase-1 (IDH1) inhibitor indicated for the treatment of adult patients with relapsed or refractory acute myeloid leukemia (AML) with a susceptible IDH1 mutation as detected by an FDA-approved test. ( 1 )

Capsules: 150 mg opaque white capsules imprinted with "OLU 150". Capsules: 150 mg ( 3 )

None. None. ( 4 )

Hepatotoxicity : Monitor liver function tests during treatment with REZLIDHIA. If hepatotoxicity occurs, interrupt and reduce or discontinue REZLIDHIA. ( 2.3 , 5.2 )

5.1 Differentiation Syndrome REZLIDHIA can cause differentiation syndrome. In the clinical trial of REZLIDHIA in patients with relapsed or refractory AML, differentiation syndrome occurred in 16% (25/153) of patients, with grade 3 or 4 differentiation syndrome occurring in 8% of patients treated, and fatalities in 1% of patients [see Adverse Reactions (6.1)]. Differentiation syndrome is associated with rapid proliferation and differentiation of myeloid cells and may be life-threatening or fatal. Symptoms of differentiation syndrome in patients treated with REZLIDHIA included leukocytosis, dyspnea, pulmonary infiltrates/pleuropericardial effusion, kidney injury, fever, edema, pyrexia, and weight gain. Of the 25 patients who experienced differentiation syndrome, 19 (76%) recovered after treatment or after dosage interruption of REZLIDHIA. Differentiation syndrome occurred as early as 1 day and up to 18 months after REZLIDHIA initiation and has been observed with or without concomitant leukocytosis. If differentiation syndrome is suspected, temporarily withhold REZLIDHIA and initiate systemic corticosteroids (e.g., dexamethasone 10 mg IV every 12 hours) for a minimum of 3 days and until resolution of signs and symptoms. If concomitant leukocytosis is observed, initiate treatment with hydroxyurea, as clinically indicated. Taper corticosteroids and hydroxyurea after resolution of symptoms. Differentiation syndrome may recur with premature discontinuation of corticosteroids and/or hydroxyurea treatment. Institute supportive measures and hemodynamic monitoring until improvement; withhold dose of REZLIDHIA and consider dose reduction based on recurrence [see Dosage and Administration ( 2.3 )] .

5.2 Hepatotoxicity REZLIDHIA can cause hepatotoxicity, presenting as increased alanine aminotransferase (ALT), increased aspartate aminotransferase (AST), increased blood alkaline phosphatase, and/or elevated bilirubin. Of 153 patients with relapsed or refractory AML who received REZLIDHIA, hepatotoxicity occurred in 23% of patients; 13% experienced grade 3 or 4 hepatotoxicity [see Adverse Reactions ( 6.1 )] . One patient treated with REZLIDHIA in combination with azacitidine in the clinical trial, a combination for which REZLIDHIA is not indicated, died from complications of drug-induced liver injury. The median time to onset of hepatotoxicity in patients with relapsed or refractory AML treated with REZLIDHIA was 1.2 months (range: 1 day to 17.5 months) after REZLIDHIA initiation, and the median time to resolution was 12 days (range: 1 day to 17 months). The most common hepatotoxicities were elevations of ALT, AST, blood alkaline phosphatase, and blood bilirubin. Monitor patients frequently for clinical symptoms of hepatic dysfunction such as fatigue, anorexia, right upper abdominal discomfort, dark urine, or jaundice. Obtain baseline liver function tests prior to initiation of REZLIDHIA, at least once weekly for the first two months, once every other week for the third month, once in the fourth month, and once every other month for the duration of therapy. If hepatic dysfunction occurs, withhold, reduce, or permanently discontinue REZLIDHIA based on recurrence/severity [see Dosage and Administration ( 2.3 )] .

The following clinically significant adverse reactions are described elsewhere in the labeling: Differentiation Syndrome [see Warnings and Precautions ( 5.1 )] Hepatotoxicity [see Warnings and Precautions ( 5.2 )] Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. The most common (≥20%) adverse reactions, including laboratory abnormalities, are aspartate aminotransferase increased, alanine aminotransferase increased, potassium decreased, sodium decreased, alkaline phosphatase increased, nausea, creatinine increased, fatigue/malaise, arthralgia, constipation, lymphocytes increased, bilirubin increased, leukocytosis, uric acid increased, dyspnea, pyrexia, rash, lipase increased, mucositis, diarrhea and transaminitis. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Rigel Pharmaceuticals, Inc. at 1-800-983-1329 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch .

6.1 Clinical Trials Experience Relapsed or Refractory AML The safety of REZLIDHIA 150 mg administered twice daily was evaluated in 153 adults with relapsed or refractory AML with an IDH1 mutation [see Clinical Studies ( 14.1 )] . Among the 153 patients who received REZLIDHIA, 35% were exposed for at least 6 months and 21% were exposed for at least 1 year. The median duration of exposure to REZLIDHIA was 4.7 months (range: 0.1 to 34 months). Serious adverse reactions occurred in 25% of patients who received REZLIDHIA. Serious adverse reactions in ≥5% included differentiation syndrome (9%) and transaminitis (6%). Fatal adverse reactions occurred in 1% of patients who received REZLIDHIA, due to differentiation syndrome. Permanent discontinuation of REZLIDHIA due to an adverse reaction occurred in 8% of patients. Adverse reactions leading to permanent discontinuation in ≥1% of patients included transaminitis, differentiation syndrome, and gallbladder disorders. Dosage interruptions of REZLIDHIA due to an adverse reaction occurred in 32% of patients. Adverse reactions which required dosage interruption in >5% of patients included transaminitis and differentiation syndrome. Dose reductions of REZLIDHIA due to an adverse reaction occurred in 11% of patients. Adverse reactions which required dose reductions in ≥2% of patients included transaminitis. The most common (≥20%) adverse reactions, including laboratory abnormalities, were aspartate aminotransferase increased, alanine aminotransferase increased, potassium decreased, sodium decreased, alkaline phosphatase increased, nausea, creatinine increased, fatigue/malaise, arthralgia, constipation, lymphocytes increased, bilirubin increased, leukocytosis, uric acid increased, dyspnea, pyrexia, rash, lipase increased, mucositis, diarrhea and transaminitis. Table 2 summarizes the adverse reactions in the clinical trial for relapsed or refractory AML. Table 2: Adverse Reactions (≥10%) in Patients with Relapsed or Refractory AML in the Clinical Trial Olutasidenib 150 mg BID N=153 Body System Adverse Reaction All Grades (%) Grade 3 or 4 (%) Gastrointestinal Disorders Nausea 38 0 Constipation 26 0 Mucositis Mucositis includes gingival hypertrophy, gingivitis, gingivitis ulcerative, oral disorder, colitis, mouth ulceration, stomatitis, tongue ulceration, oral pain, oropharyngeal pain, pharyngitis, proctalgia, and colitis ischemic. 23 3 Diarrhea 20 1 Abdominal pain Includes multiple similar adverse reaction terms. 18 1 Vomiting 17 1 General Disorders and Administration Site Conditions Fatigue/malaise 36 3 Pyrexia 24 1 Edema 18 3 Musculoskeletal and Connective Tissue Disorders Arthralgia Arthralgia grouped term includes arthralgia, bone pain, back pain, neck pain, pain in extremity, arthritis, joint effusion, joint range of motion decreased, and joint swelling. 28 3 Blood System and Lymphatic Disorders Leukocytosis 25 9 Differentiation syndrome Includes fatal adverse reaction. ' Symptoms of differentiation syndrome in patients treated with REZLIDHIA included leukocytosis, dyspnea, pulmonary infiltrates/pleuropericardial effusion, kidney injury, fever, edema, pyrexia, and weight gain. 16 8 Respiratory, Thoracic and Mediastinal Disorders Dyspnea ' Dyspnea grouped term includes acute respiratory distress syndrome, dyspnea, dyspnea exertional, hypoxia, oxygen saturation decreased, respiratory distress, respiratory failure. 24 5 Cough 17 1 Skin and subcutaneous tissue disorders Rash 24 1 Investigations Transaminitis Transaminitis grouped term includes alanine aminotransferase increased, aspartate aminotransferase increased, hepatic enzyme increased, hypertransaminasemia, liver function test abnormal, liver function test increased, transaminases increased, hepatitis acute, and blood alkaline phosphatase increased. 20 12 Metabolism and Nutrition Disorders Decreased appetite 16 2 Nervous System Disorders Headache 13 0 Vascular Disorders Hypertension 10 5 Clinically relevant adverse reactions in <10% of patients who received REZLIDHIA include: Gallbladder disorders: biliary tract disorder, biliary colic, cholangitis, and cholestasis Electrocardiogram QT prolonged Table 3 summarizes the laboratory abnormalities in the clinical trial for relapsed or refractory AML. Table 3: Most Common (≥10%) New or Worsening Laboratory Abnormalities in Patients with Relapsed or Refractory AML in the Clinical Trial Olutasidenib The denominator used to calculate the rate varied from 143 to 152 based on the number of patients with a baseline value and at least one post-treatment value. Parameter All Grades (%) Grade 3 or 4 (%) Aspartate aminotransferase increased 47 10 Alanine aminotransferase increased 46 13 Potassium decreased 46 9 Sodium decreased 42 7 Alkaline phosphatase increased 42 7 Creatinine increased 38 2 Lymphocytes increased 26 3 Bilirubin increased 26 2 Uric acid increased 25 3 Lipase increased 24 8

Strong or moderate CYP3A Inducers: Avoid concomitant use. ( 7.1 ) Sensitive CYP3A Substrates: Avoid concomitant use. Monitor if unavoidable. ( 7.1 )

7.1 Effect of Other Drugs on Olutasidenib Strong or Moderate CYP3A4 Inducers Avoid concomitant use of REZLIDHIA with strong or moderate CYP3A inducers. Olutasidenib is a CYP3A substrate. Concomitant use of REZLIDHIA with a strong CYP3A inducer decreases olutasidenib Cmax and AUC, which may reduce REZLIDHIA efficacy [see Clinical Pharmacology ( 12.3 )] . Concomitant use of REZLIDHIA with a moderate CYP3A inducer may also decrease olutasidenib Cmax and AUC, which may also reduce REZLIDHIA efficacy, based on observations from concomitant use with a strong CYP3A inducer.

7.2 Effect of Olutasidenib on Other Drugs Sensitive CYP3A Substrates Avoid concomitant use of REZLIDHIA with sensitive CYP3A substrates unless otherwise instructed in the substrates prescribing information. If concomitant use is unavoidable, monitor patients for loss of therapeutic effect of these drugs. Olutasidenib induces CYP3A. Concomitant use of REZLIDHIA may decrease plasma concentrations of sensitive CYP3A substrates, which may reduce the substrate’s efficacy [see Clinical Pharmacology ( 12.3 )] .

Lactation: Advise not to breastfeed. ( 8.2 )

8.1 Pregnancy Risk Summary Based on animal embryo-fetal toxicity studies, REZLIDHIA may cause fetal harm when administered to a pregnant woman. There are no available data on REZLIDHIA use in pregnant women to evaluate for a drug-associated risk. In embryo-fetal development studies, oral olutasidenib resulted in embryo-fetal death and altered fetal growth when administered to pregnant rats and rabbits during the period of organogenesis at exposures up to 10 times and 0.7 times, respectively, the human exposure at the recommended daily dose (see Data ) . Advise pregnant women of the potential risk to a fetus. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2%-4% and 15%-20%, respectively. Data Animal Data Olutasidenib was administered twice daily via oral gavage at dose levels of 25, 125, or 250 mg/kg/dose (50, 250, or 500 mg/kg/day) to pregnant rats during organogenesis (gestation days 6-17). An increase in fetal supernumerary rib was observed at the high dose (10 times the AUC at the clinical dose of 150 mg BID). In a pilot study, administration of olutasidenib orally to pregnant rats during organogenesis resulted in an increase in post-implantation loss at doses of 250 and 450 mg/kg/day (9 and 10 times the AUC at the clinical dose of 150 mg BID). Olutasidenib was administered twice daily via oral gavage at dose levels of 10, 20, or 40 mg/kg/dose (20, 40, or 80 mg/kg/day) to pregnant rabbits during the period of organogenesis (gestation days 7- 20). Maternal toxicity noted as reduced body weight gain occurred at 80 mg/kg/day. An increase in fetal supernumerary rib and increased post-implantation loss occurred at the high dose of 80 mg/kg/day (0.7 times the AUC at the clinical dose of 150 mg BID).

8.2 Lactation Risk Summary There are no data on the presence of olutasidenib or its metabolites in human milk, the effects on the breastfed child, or milk production. Because many drugs are excreted in human milk, and due to the potential for adverse reactions in a breastfed child, advise women not to breastfeed during treatment with REZLIDHIA and for 2 weeks after the last dose.

8.4 Pediatric Use The safety and effectiveness of REZLIDHIA have not been established in pediatric patients.

8.5 Geriatric Use Among the 153 patients with relapsed or refractory AML with an IDH1 mutation treated with REZLIDHIA, 116 (76%) were 65 years of age or older and 48 (31%) were 75 years or older. No overall differences in effectiveness were observed between patients 65 years and older and younger patients. Compared to patients younger than 65 years of age, an increase in incidence of hepatotoxicity and hypertension was observed in patients ≥65 years of age.

8.6 Renal Impairment No dosage modification is recommended for patients with mild to moderate renal impairment (creatinine clearance [CLcr] 30 to <90 mL/min, as estimated by Cockcroft-Gault). The recommended dosage of REZLIDHIA has not been established in patients with severe renal impairment (CLcr 15 to 29 mL/min as estimated by Cockcroft-Gault), kidney failure (CLcr <15 mL/min, as estimated by Cockcroft-Gault), and patients on dialysis [see Clinical Pharmacology ( 12.3 )] .

8.7 Hepatic Impairment No dosage modification is recommended for patients with mild (total bilirubin ≤ULN and any AST >ULN or total bilirubin >1 to 1.5 times ULN and any AST) or moderate (total bilirubin >1.5 to 3 times ULN and any AST) hepatic impairment [see Clinical Pharmacology ( 12.3 )] . In patients with mild or moderate hepatic impairment, closely monitor for increased probability of differentiation syndrome [see Dosage and Administration ( 2.3 ) and Warnings and Precautions ( 5.1 )] . The recommended dosage of REZLIDHIA has not been established in patients with severe hepatic impairment (total bilirubin >3 times ULN with any AST) [see Clinical Pharmacology ( 12.3 )] .

Olutasidenib is a small-molecule inhibitor of mutated isocitrate dehydrogenase-1 (IDH1). In patients with AML, susceptible IDH1 mutations are defined as those leading to increased levels of 2-hydroxyglutarate (2-HG) in the leukemia cells and where efficacy is predicted by 1) clinically meaningful remissions with the recommended dose of olutasidenib and/or 2) inhibition of mutant IDH1 enzymatic activity at concentrations of olutasidenib sustainable at the recommended dosage according to validated methods. The most common of such mutations in patients with AML are R132H and R132C substitutions. In vitro, olutasidenib inhibited mutated IDH1 R132H, R132L, R132S, R132G, and R132C proteins; wild-type IDH1 or mutated IDH2 proteins were not inhibited. Olutasidenib inhibition of mutant IDH1 led to decreased 2-HG levels in vitro and in in vivo xenograft models.