Pirtobrutinib

12.1 Mechanism of action Pirtobrutinib is a small molecule, noncovalent inhibitor of BTK. BTK is a signaling protein of the B-cell antigen receptor (BCR) and cytokine receptor pathways. In B-cells, BTK signaling results in activation of pathways necessary for B-cell proliferation, trafficking, chemotaxis, and adhesion. Pirtobrutinib binds to wild type BTK and BTK harboring C481 mutations, leading to inhibition of BTK kinase activity. In nonclinical studies, pirtobrutinib inhibited BTK-mediated B-cell CD69 expression and inhibited malignant B-cell proliferation. Pirtobrutinib showed dose-dependent anti-tumor activities in BTK wild type and BTK C481S mutant mouse xenograft models.

1 INDICATIONS AND USAGE JAYPIRCA ® is a kinase inhibitor indicated for the treatment of: Adult patients with relapsed or refractory mantle cell lymphoma (MCL) after at least two lines of systemic therapy, including a BTK inhibitor. ( 1.1 ). This indication is approved under accelerated approval based on response rate. Continued approval for this indication may be contingent upon verification and description of clinical benefit in a confirmatory trial. Adult patients with relapsed or refractory chronic lymphocytic leukemia or small lymphocytic lymphoma (CLL/SLL) who have previously been treated with a covalent BTK inhibitor. ( 1.2 ). 1.1 Mantle Cell Lymphoma JAYPIRCA ® is indicated for the treatment of adult patients with relapsed or refractory mantle cell lymphoma (MCL) after at least two lines of systemic therapy, including a BTK inhibitor. This indication is approved under accelerated approval based on response rate [see Clinical Studies ( 14.1 )]. Continued approval for this indication may be contingent upon verification and description of clinical benefit in a confirmatory trial. 1.2 Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma JAYPIRCA is indicated for the treatment of adult patients with relapsed or refractory chronic lymphocytic leukemia or small lymphocytic lymphoma (CLL/SLL) who have previously been treated with a covalent BTK inhibitor.

2 DOSAGE AND ADMINISTRATION Recommended dosage: 200 mg orally once daily; swallow whole with water, with or without food. Do not cut, crush, or chew tablets. ( 2.1 ) Manage toxicity using treatment interruption, dosage reduction, or discontinuation. ( 2.2 ) Reduce dose in patients with severe renal impairment. ( 2.3 , 8.6 ) 2.1 Recommended Dosage The recommended dosage of JAYPIRCA is 200 mg orally once daily until disease progression or unacceptable toxicity. Advise patients of the following: Swallow tablets whole with water. Do not cut, crush, or chew tablets. Take JAYPIRCA at the same time each day. JAYPIRCA may be taken with or without food. If a dose of JAYPIRCA is missed by more than 12 hours, do not make up the dose and take the next dose as scheduled. 2.2 Dosage Modifications for Adverse Reactions Recommended dosage modifications of JAYPIRCA for adverse reactions are presented in Table 1 [see Warnings and Precautions ( 5.1 , 5.2 , 5.3 , and 5.4 )] . Table 1: Recommended Dosage Modification of JAYPIRCA for Adverse Reactions Dose modification is not recommended for asymptomatic lymphocytosis. Asymptomatic lipase increase may not necessarily warrant dose modification. a Evaluate the benefit-risk before resuming treatment at the same dose for a Grade 4 non-hematological toxicity. Adverse Reaction Occurrences Requiring Dosage Modification Modification (Starting Dosage: 200 mg once daily) Grade 3 or greater non-hematologic toxicity a Absolute neutrophil count < 1 to 0.5 x 10 9 /L with fever and/or infection Absolute neutrophil count < 0.5 x 10 9 /L lasting 7 or more days Platelet count < 50 to 25 x 10 9 /L with bleeding Platelet count < 25 x 10 9 /L First occurrence Interrupt JAYPIRCA until recovery to Grade 1 or baseline; restart at original dosage (200 mg once daily) a . Second occurrence Interrupt JAYPIRCA until recovery to Grade 1 or baseline; restart at 100 mg once daily. Third occurrence Interrupt JAYPIRCA until recovery to Grade 1 or baseline; restart at 50 mg once daily. Fourth occurrence Discontinue JAYPIRCA. 2.3 Dosage Modifications for Patients with Severe Renal Impairment For patients with severe renal impairment (eGFR 15-29 mL/min), reduce the JAYPIRCA dose to 100 mg once daily if the current dose is 200 mg once daily otherwise reduce the dose by 50 mg. If the current dosage is 50 mg once daily, discontinue JAYPIRCA [see Use in Specific Populations ( 8.7 ), Clinical Pharmacology ( 12.3 )] . No dosage adjustment of JAYPIRCA is recommended in patients with mild to moderate renal impairment (eGFR 30-89 mL/min). 2.4 Dosage Modifications for Concomitant Use with Strong CYP3A Inhibitors Avoid concomitant use of strong CYP3A inhibitors with JAYPIRCA [see Drug Interactions ( 7.1 ), Clinical Pharmacology ( 12.3 )] . If concomitant use of a strong CYP3A inhibitor is unavoidable, reduce the JAYPIRCA dose by 50 mg. If the current dosage is 50 mg once daily, interrupt JAYPIRCA treatment for the duration of strong CYP3A inhibitor use. After discontinuation of a strong CYP3A inhibitor for 5 half-lives, resume the JAYPIRCA dose that was taken prior to initiating the strong CYP3A inhibitor. 2.5 Dosage Modifications for Concomitant Use with CYP3A Inducers Avoid concomitant use of strong or moderate CYP3A inducers with JAYPIRCA [see Drug Interactions ( 7.1 ), Clinical Pharmacology ( 12.3 )] . If concomitant use with moderate CYP3A inducers is unavoidable and the current dosage of JAYPIRCA is 200 mg once daily, increase the dose to 300 mg. If the current dosage is 50 mg or 100 mg once daily, increase the dose by 50 mg.

6 ADVERSE REACTIONS The following clinically significant adverse reactions are described elsewhere in the labeling: Infections [see Warnings and Precautions ( 5.1 )] Hemorrhage [see Warnings and Precautions ( 5.2 )] Cytopenias [see Warnings and Precautions ( 5.3 )] Atrial Fibrillation and Atrial Flutter [see Warnings and Precautions ( 5.4 )] Second Primary Malignancies [see Warnings and Precautions ( 5.5 )] Hepatotoxicity, including DILI [see Warnings and Precautions ( 5.6 )] Most common adverse reactions (≥ 30%), including laboratory abnormalities, are fatigue, neutrophil count decreased, platelet count decreased, hemoglobin decreased, leukocytes decreased, lymphocyte count decreased and calcium decreased. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Eli Lilly and Company at 1-800-LillyRx (1-800-545-5979) or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be compared to rates in the clinical trials of another drug and may not reflect the rates observed in the general patient population. The data in the WARNINGS AND PRECAUTIONS reflect exposure to JAYPIRCA as a single-agent, administered at 200 mg once daily in 704 patients with hematologic malignancies in the BRUIN and the BRUIN-CLL-321 studies. Among these 704 patients, the median duration of exposure was 12 months; 65% were exposed for at least 6 months and 50% were exposed for at least one year. In this pooled safety population, the most common (≥ 30%) adverse reactions, including laboratory abnormalities, were decreased neutrophil count (54%), decreased hemoglobin (43%), decreased leukocytes (32%), fatigue (31%), decreased platelets (31%), decreased lymphocyte count (31%), and calcium decreased (30%) Mantle Cell Lymphoma BRUIN The safety of JAYPIRCA was evaluated in the BRUIN trial, an open-label, multicohort, single-arm study in patients with previously treated MCL who received a prior BTK inhibitor [see Clinical Studies ( 14.1 ) ] . The trial required a platelet count ≥ 50 x 10 9 /L, absolute neutrophil count ≥ 0.75 x 10 9 /L, hepatic transaminases ≤ 2.5 times upper limit of normal (ULN), and an ECOG performance status of 0 to 2. The trial excluded patients with active central nervous system (CNS) involvement by lymphoma, significant cardiovascular disease, major bleeding or grade ≥ 3 arrhythmia with a prior BTK inhibitor, prolonged QTc interval, or need for a strong CYP3A inhibitor or inducer or strong P-gp inhibitor. Patients received JAYPIRCA 200 mg orally once daily until disease progression or unacceptable toxicity (n = 128); 36% were exposed for 6 months or longer and 10% were exposed for at least one year. The median number of prior therapies was 3 (range: 1-9). The median age was 71 years (range: 46 to 88 years) and 80% of patients were male. Race was reported for all patients; 78% were White, 14% were Asian, 2.3% were Black, and 2.3% were Hispanic or Latino. Serious adverse reactions occurred in 38% of patients who received JAYPIRCA. Serious adverse reactions that occurred in ≥ 2% of patients were pneumonia (14%), COVID-19 (4.7%), musculoskeletal pain (3.9%), hemorrhage (2.3%), pleural effusion (2.3%), and sepsis (2.3%). Fatal adverse reactions within 28 days of the last dose of JAYPIRCA occurred in 7% of patients, most commonly due to infections (4.7%) including COVID-19 (3.1% of all patients). Adverse reactions led to dose reductions in 4.7%, treatment interruption in 32%, and permanent discontinuation of JAYPIRCA in 9%. Adverse reactions that resulted in dosage modification in > 5% of patients included pneumonia and neutropenia. Adverse reactions which resulted in permanent discontinuation of JAYPIRCA in > 1% of patients included pneumonia. The most common adverse reactions (≥ 15%), excluding laboratory terms, were fatigue, musculoskeletal pain, diarrhea, edema, dyspnea, pneumonia, and bruising. Table 2 summarizes select adverse reactions in BRUIN. Table 2: Adverse Reactions (≥ 10%) in Patients with MCL Who Received JAYPIRCA JAYPIRCA 200 mg once daily N = 128 a Each term listed includes other related terms. b includes 1 fatality from COVID-19 pneumonia. c includes 1 fatality from hemorrhage. Adverse Reactions a All Grades (%) Grade 3-4 (%) General Disorders Fatigue 29 1.6 Edema 18 0.8 Fever 13 - Musculoskeletal and Connective Tissue Disorders Musculoskeletal pain 27 3.9 Arthritis or arthralgia 12 0.8 Gastrointestinal Disorders Diarrhea 19 - Constipation 13 - Abdominal pain 11 0.8 Nausea 11 - Respiratory, thoracic, and mediastinal disorders Dyspnea 17 2.3 Cough 14 - Injury Bruising 16 - Infections Pneumonia 16 b 14 Upper respiratory tract infections 10 0.8 Nervous system disorders Peripheral neuropathy 14 0.8 Dizziness 10 - Skin and subcutaneous disorders Rash 14 - Vascular disorders Hemorrhage 11 c 3.1 Clinically relevant adverse reactions in < 10% include vi

7 DRUG INTERACTIONS Strong CYP3A Inhibitors: Avoid concomitant use. If concomitant use is unavoidable, reduce the JAYPIRCA dose. ( 2.4 , 7.1 ) Strong or Moderate CYP3A Inducers: Avoid concomitant use. If concomitant use of moderate CYP3A inducers is unavoidable, increase the JAYPIRCA dose. ( 2.5 , 7.1 ) Sensitive CYP2C8, CYP2C19, CYP3A, P-gp, or BCRP Substrates: For substrates where minimal concentration changes may increase the risk of adverse reactions, follow recommendations for co-administration with CYP2C8, CYP2C19, CYP3A, P-gp, or BCRP inhibitors provided in their approved product labeling. ( 7.2 ) 7.1 Effect of Other Drugs on JAYPIRCA Strong CYP3A Inhibitors Pirtobrutinib is a CYP3A substrate. Concomitant use of JAYPIRCA with a strong CYP3A inhibitor increased pirtobrutinib systemic exposure [see Clinical Pharmacology ( 12.3 )] , which may increase the risk of JAYPIRCA adverse reactions. Avoid concomitant use of strong CYP3A inhibitors during treatment with JAYPIRCA. If concomitant use of strong CYP3A inhibitors is unavoidable, reduce the JAYPIRCA dosage [see Dosage and Administration ( 2.4 )] . Strong or Moderate CYP3A Inducers Concomitant use of JAYPIRCA with a strong or moderate CYP3A inducer decreased pirtobrutinib systemic exposure [see Clinical Pharmacology ( 12.3 )] , which may reduce JAYPIRCA efficacy. Avoid concomitant use of JAYPIRCA with strong or moderate CYP3A inducers. If concomitant use of moderate CYP3A inducers is unavoidable, increase the JAYPIRCA dosage [see Dosage and Administration ( 2.5 )] . 7.2 Effect of JAYPIRCA on Other Drugs Sensitive CYP2C8, CYP2C19, CYP3A, P-gp, or BCRP Substrates JAYPIRCA is a P-gp inhibitor, a moderate CYP2C8 and BCRP inhibitor, and a weak CYP2C19 and CYP3A inhibitor. Concomitant use of JAYPIRCA with sensitive P-gp, CYP2C8, BCRP, CYP2C19, or CYP3A substrates increased their plasma concentrations [see Clinical Pharmacology ( 12.3 )], which may increase the risk of adverse reactions related to these substrates for drugs which are sensitive to minimal concentration changes. Follow recommendations for sensitive CYP2C8, CYP2C19, CYP3A, P-gp, or BCRP substrates provided in their approved product labeling.