Niraparib

12.1 Mechanism of Action Niraparib is an inhibitor of PARP enzymes, including PARP-1 and PARP-2, that play a role in DNA repair. In vitro studies have shown that niraparib-induced cytotoxicity may involve inhibition of PARP enzymatic activity and increased formation of PARP-DNA complexes resulting in DNA damage, apoptosis, and cell death. Increased niraparib‑induced cytotoxicity was observed in tumor cell lines with or without deficiencies in BRCA1/2 . Niraparib decreased tumor growth in mouse xenograft models of human cancer cell lines with deficiencies in BRCA1/2 and in human patient‑derived xenograft tumor models with homologous recombination deficiency (HRD) that had either mutated or wild-type BRCA1/2 . Abiraterone acetate is converted in vivo to abiraterone, an androgen biosynthesis inhibitor, that inhibits 17 α-hydroxylase/C17,20-lyase (CYP17). This enzyme is expressed in testicular, adrenal, and prostatic tumor tissues and is required for androgen biosynthesis. CYP17 catalyzes two sequential reactions: 1) the conversion of pregnenolone and progesterone to their 17α-hydroxy derivatives by 17α-hydroxylase activity and 2) the subsequent formation of dehydroepiandrosterone (DHEA) and androstenedione, respectively, by C17, 20 lyase activity. DHEA and androstenedione are androgens and are precursors of testosterone. Inhibition of CYP17 by abiraterone can also result in increased mineralocorticoid production by the adrenals [see Warnings and Precautions (5.9) ] . Androgen sensitive prostatic carcinoma responds to treatment that decreases androgen levels. Androgen deprivation therapies, such as treatment with GnRH agonists or orchiectomy, decrease androgen production in the testes but do not affect androgen production by the adrenals or in the tumor. Abiraterone decreased serum testosterone and other androgens in patients in the placebo-controlled clinical trial. It is not necessary to monitor the effect of abiraterone on serum testosterone levels. Changes in serum

1 INDICATIONS AND USAGE AKEEGA with prednisone is indicated for the treatment of adult patients with deleterious or suspected deleterious BRCA2 -mutated ( BRCA2 m) metastatic castration-sensitive prostate cancer (mCSPC). AKEEGA with prednisone is indicated for the treatment of adult patients with deleterious or suspected deleterious BRCA -mutated ( BRCA m) metastatic castration-resistant prostate cancer (mCRPC). Select patients for therapy based on an FDA-approved test for AKEEGA [see Dosage and Administration (2.1) ] . AKEEGA is a combination of niraparib, a poly (ADP-ribose) polymerase (PARP) inhibitor, and abiraterone acetate, a CYP17 inhibitor indicated with prednisone for the treatment of adult patients with: deleterious or suspected deleterious BRCA2 -mutated ( BRCA2 m) metastatic castration-sensitive prostate cancer (mCSPC). deleterious or suspected deleterious BRCA -mutated ( BRCA m) metastatic castration-resistant prostate cancer (mCRPC). Select patients for therapy based on an FDA-approved test for AKEEGA. ( 1 , 2.1 )

2 DOSAGE AND ADMINISTRATION BRCA2 m mCSPC: The recommended dosage of AKEEGA is 200 mg niraparib/1,000 mg abiraterone acetate orally once daily in combination with 5 mg prednisone daily until disease progression or unacceptable toxicity. ( 2.2 ) BRCA m mCRPC : The recommended dosage of AKEEGA is 200 mg niraparib/1,000 mg abiraterone acetate orally once daily in combination with 10 mg prednisone daily until disease progression or unacceptable toxicity. ( 2.2 ) Patients receiving AKEEGA should also receive a gonadotropin-releasing hormone (GnRH) analog concurrently or should have had bilateral orchiectomy. ( 2.2 ) Take AKEEGA on an empty stomach at least one hour before or two hours after food. ( 2.2 ) For adverse reactions, consider interruption of treatment, dose reduction, or dose discontinuation. ( 2.3 ) 2.1 Patient Selection Select patients for the treatment of mCSPC with AKEEGA based on the presence of a BRCA2 gene alteration [see Clinical Studies (14.1) ] . Select patients for the treatment of mCRPC with AKEEGA based on the presence of a BRCA gene alteration [see Clinical Studies (14.2) ] . Information on FDA-approved tests is available at: http://www.fda.gov/CompanionDiagnostics. 2.2 Recommended Dosage BRCA2- mutated ( BRCA2 m) Metastatic Castration-Sensitive Prostate Cancer (mCSPC) The recommended dosage of AKEEGA is 200 mg niraparib/1,000 mg abiraterone acetate orally once daily in combination with 5 mg prednisone once daily until disease progression or unacceptable toxicity. BRCA -mutated ( BRCA m) Metastatic Castration-Resistant Prostate Cancer (mCRPC) The recommended dosage of AKEEGA is 200 mg niraparib/1,000 mg abiraterone acetate orally once daily in combination with 10 mg prednisone once daily until disease progression or unacceptable toxicity. Patients receiving AKEEGA should also receive a gonadotropin-releasing hormone (GnRH) analog concurrently or should have had bilateral orchiectomy. Take AKEEGA on an empty stomach at least one hour before or two hours after food. Swallow tablets whole with water. Do not break, crush, or chew tablets. If a patient misses a dose, instruct patients to take the dose as soon as possible on the same day and resume their next dose at the normal schedule the following day. 2.3 Dosage Modification for Adverse Reactions The recommended dosage modifications for AKEEGA are provided in Table 1. Treatment with AKEEGA should not be reinitiated until the toxicity has resolved to Grade 1 or baseline. If the toxicity is attributed to one component of AKEEGA, the other component of AKEEGA may be continued as a single agent at the current dose until the adverse reaction resolves and AKEEGA can be resumed (see Table 1 ). Table 1: Dosage Modifications for Adverse Reactions Adverse Reaction Severity Dosage Modification Myelosuppression [see Warnings and Precautions (5.2) ] Hemoglobin <8 g/dL Withhold AKEEGA and monitor blood counts weekly. When hemoglobin returns to ≥9 g/dL, resume at the reduced dose of AKEEGA 100 mg/1,000 mg once daily and monitor blood counts weekly for 28 days and as clinically indicated. Permanently discontinue AKEEGA if hemoglobin has not returned to acceptable levels within 28 days of the dose interruption period or if the patient has already undergone dose reduction to 100 mg/1,000 mg once daily. If myelodysplastic syndrome or acute myeloid leukemia (MDS/AML) is confirmed, discontinue AKEEGA [see Warnings and Precautions (5.1)]. Platelet count <100,000/mcL First occurrence: Withhold AKEEGA for a maximum of 28 days and monitor blood counts weekly until platelet counts return to ≥100,000/mcL. Resume AKEEGA at same or the reduced dose of 100 mg/1,000 mg once daily. If platelet count is <75,000/mcL, resume at the reduced dose of AKEEGA 100 mg/1,000 mg once daily. Second occurrence: Withhold AKEEGA for a maximum of 28 days and monitor blood counts weekly until platelet counts return to ≥100,000/mcL. Resume at the reduced dose of AKEEGA 100 mg/1,000 mg once daily. Permanently discontinue AKEEGA if the platelet count has not returned to acceptable levels within 28 days of the dose interruption period or if the patient has already undergone dose reduction to 100 mg/1,000 mg once daily. Neutrophil <1,000/mcL Withhold AKEEGA and monitor blood counts weekly. When neutrophil counts return to ≥1,500/mcL, resume at the reduced dose of AKEEGA 100 mg/1,000 mg once daily and monitor blood counts weekly for 28 days and as clinically indicated. Permanently discontinue AKEEGA if neutrophils have not returned to acceptable levels within 28 days of the dose interruption period or if the patient has already undergone dose reduction to 100 mg/1,000 mg once daily. Hematologic adverse reaction requiring transfusion Consider platelet transfusion for patients with platelet count ≤10,000/mcL. If there are other risk factors such as coadministration of anticoagulation or antiplatelet drugs, consider interrupting these drugs and/or transfusion at a higher platelet count. Resume at t

6 ADVERSE REACTIONS The following adverse reactions are discussed elsewhere in the labeling: Myelodysplastic syndrome/acute myeloid leukemia [see Warnings and Precautions (5.1) ] Myelosuppression [see Warnings and Precautions (5.2) ] Hypokalemia, fluid retention, and cardiovascular adverse reactions [see Warnings and Precautions (5.3) ] Hepatotoxicity [see Warnings and Precautions (5.4) ] Adrenocortical insufficiency [see Warnings and Precautions (5.5) ] Hypoglycemia [see Warnings and Precautions (5.6) ] Increased fractures and mortality in combination with Radium 223 Dichloride [see Warnings and Precautions (5.7) ] Posterior reversible encephalopathy syndrome [see Warnings and Precautions (5.8) ] The most common adverse reactions (≥20%), including laboratory abnormalities, are decreased hemoglobin, decreased lymphocytes, musculoskeletal pain, fatigue, decreased platelets, increased alkaline phosphatase, constipation, hypertension, nausea, decreased neutrophils, increased creatinine, increased potassium, decreased potassium, increased AST, fluid retention/edema, increased bilirubin, respiratory tract infection and arrhythmia. ( 6 ) To report SUSPECTED ADVERSE REACTIONS, contact Janssen Biotech, Inc. at 1-800-526-7736 (1-800-JANSSEN) or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trial Experience 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 safety population described in the WARNINGS and PRECAUTIONS reflect exposure to AKEEGA (niraparib 200 mg and abiraterone acetate 1,000 mg) in BRCA2 m patients (N=162) in the AMPLITUDE study and in BRCA m patients in Cohort 1 (N=113) in the MAGNITUDE study unless otherwise specified. BRCA2 -mutated Metastatic Castration-Sensitive Prostate Cancer (mCSPC) The safety of AKEEGA in patients with BRCA2 m mCSPC was evaluated in AMPLITUDE [see Clinical Studies (14.1) ]. Patients were randomized to receive either AKEEGA (niraparib 200 mg and abiraterone acetate 1,000 mg once daily) (n=162), or placebo and abiraterone acetate (n=161) until unacceptable toxicity or progression. Patients in both arms also received prednisone 5 mg daily. The median duration of exposure for AKEEGA was 26 months (range: 0 to 48 months). Serious adverse reactions occurred in 36% of patients who received AKEEGA. Serious adverse reactions reported in >2% of patients included anemia (4.9%), and pneumonia (3.7%). Fatal adverse reactions occurred in 4.9% of patients who received AKEEGA, including sudden death (1.9%), COVID-19 pneumonia (1.2%), pneumocystis jirovecii pneumonia (0.6%), pneumonia (0.6%), and cardio-respiratory arrest (0.6%). Permanent discontinuation of any component of AKEEGA due to an adverse reaction occurred in 13% of patients. Dosage interruptions of any component of AKEEGA due to an adverse reaction occurred in 67% of patients. Adverse reactions which required dosage interruption in >2% of patients included anemia (30%), COVID-19 (10%), hypertension (9%), neutropenia (8%), thrombocytopenia (8%), hypokalemia (7%), vomiting (4.9%), fatigue (4.3%), diarrhea (2.5%), and pneumonia (2.5%). Dose reductions of any component of AKEEGA due to an adverse reaction occurred in 25% of patients. Adverse reactions which required dose reductions in >2% of patients included anemia (17%). The most common adverse reactions (>20%), including laboratory abnormalities, in patients who received AKEEGA were decreased hemoglobin, decreased lymphocyte count, hypertension, decreased neutrophil count, musculoskeletal pain, decreased platelet count, constipation, fatigue, decreased potassium, increase creatinine, nausea, increased alkaline phosphate, increased aspartate aminotransferase, respiratory tract infection, arrhythmia, increased blood bilirubin, and fluid retention/edema. Table 2: Adverse Reactions (>20%) in Patients with BRCA2m mCSPC Who Received AKEEGA (with a Difference of ≥5% Compared to Placebo) in AMPLITUDE Adverse Reaction AKEEGA (N=162) Placebo with Abiraterone Acetate (N=161) All Grades % Grade 3 or 4 % All Grades % Grade 3 or 4 % Vascular disorders Hypertension Grouped terms including multiple similar terms 51 31 36 19 Musculoskeletal and connective tissue disorders Musculoskeletal pain 45 6 58 4.3 Gastrointestinal disorders Constipation 41 0 17 0.6 Nausea 30 0 17 0 General disorders and administration Fatigue 39 4.3 29 3.1 Respiratory, thoracic and mediastinal disorders Respiratory Tract Infection 23 0.6 13 0.6 Cardiac disorders Arrhythmia 23 3.7 9 2.5 Clinically relevant adverse reactions that occurred in ≤20% of patients receiving AKEEGA plus prednisone were hot flush (18%), vomiting (17%), dizziness (17%), abdominal pain (15%), weight decreased (14%), diarrhea (14%), decreased appetite (12%), headache (12%), hemorrhage (12%), dyspnea (10%), urinary tract infectio

7 DRUG INTERACTIONS Strong CYP3A4 Inducers: Avoid coadministration. ( 7.1 ) CYP2D6 Substrates: Avoid coadministration of AKEEGA with CYP2D6 substrates for which minimal changes in concentration may lead to serious toxicities. If alternative treatments cannot be used, consider a dose reduction of the concomitant CYP2D6 substrate. ( 7.2 ) 7.1 Effect of Other Drugs on AKEEGA Effect of CYP3A4 Inducers Avoid coadministration with strong CYP3A4 inducers [see Clinical Pharmacology (12.3) ] . Abiraterone is a substrate of CYP3A4. Strong CYP3A4 inducers may decrease abiraterone concentrations [see Clinical Pharmacology (12.3) ], which may reduce the effectiveness of abiraterone. 7.2 Effects of AKEEGA on Other Drugs CYP2D6 Substrates Avoid coadministration unless otherwise recommended in the Prescribing Information for CYP2D6 substrates for which minimal changes in concentration may lead to serious toxicities. If alternative treatments cannot be used, consider a dose reduction of the concomitant CYP2D6 substrate drug. Abiraterone is a CYP2D6 moderate inhibitor. AKEEGA increases the concentration of CYP2D6 substrates [see Clinical Pharmacology (12.3) ], which may increase the risk of adverse reactions related to these substrates. CYP2C8 Substrates Monitor patients for signs of toxicity related to a CYP2C8 substrate for which a minimal change in plasma concentration may lead to serious or life-threatening adverse reactions. Abiraterone is a CYP2C8 inhibitor. AKEEGA increases the concentration of CYP2C8 substrates [see Clinical Pharmacology (12.3) ], which may increase the risk of adverse reactions related to these substrates.