Neratinib

NERLYNX is a kinase inhibitor indicated: As a single agent, for the extended adjuvant treatment of adult patients with early-stage HER2-positive breast cancer, to follow adjuvant trastuzumab-based therapy. ( 1.1 ) In combination with capecitabine, for the treatment of adult patients with advanced or metastatic HER2-positive breast cancer who have received two or more prior anti-HER2 based regimens in the metastatic setting. ( 1.2 )

1.1 Extended Adjuvant Treatment of Early-Stage Breast Cancer NERLYNX as a single agent is indicated for the extended adjuvant treatment of adult patients with early-stage human epidermal growth factor receptor 2 (HER2)-positive breast cancer, to follow adjuvant trastuzumab based therapy [see Clinical Studies ( 14.1 )] .

1.2 Advanced or Metastatic Breast Cancer NERLYNX in combination with capecitabine is indicated for the treatment of adult patients with advanced or metastatic HER2-positive breast cancer who have received two or more prior anti-HER2 based regimens in the metastatic setting [see Clinical Studies ( 14.2 )] .

Tablets: 40 mg neratinib (equivalent to 48.31 mg of neratinib maleate). Film-coated, red, oval shaped and debossed with 'W104' on one side and plain on the other side. Tablets: 40 mg. ( 3 )

None. None. ( 4 )

Diarrhea: Manage diarrhea through either NERLYNX dose escalation or loperamide prophylaxis ( 2.1 , 2.2 ). If diarrhea occurs despite recommended prophylaxis, treat with additional antidiarrheals, fluids, and electrolytes as clinically indicated. Withhold NERLYNX in patients experiencing severe and/or persistent diarrhea. Permanently discontinue NERLYNX in patients experiencing Grade 4 diarrhea or Grade ≥2 diarrhea that occurs after maximal dose reduction. ( 2.3 , 5.1 ) Hepatotoxicity: Monitor liver function tests monthly for the first 3 months of treatment, then every 3 months while on treatment and as clinically indicated. Withhold NERLYNX in patients experiencing Grade 3 liver abnormalities and permanently discontinue NERLYNX in patients experiencing Grade 4 liver abnormalities. ( 2.3 , 5.2 ) Embryo-Fetal Toxicity: NERLYNX can cause fetal harm. Advise patients of potential risk to a fetus and to use effective contraception. ( 5.3 , 8.1 , 8.3 )

5.1 Diarrhea Severe diarrhea and sequelae, such as dehydration, hypotension, and renal failure occurred during treatment with NERLYNX. Diarrhea was reported in 95% of NERLYNX-treated patients in ExteNET, a randomized placebo-controlled trial in the extended adjuvant setting who were not required to receive antidiarrheal prophylaxis. In the NERLYNX arm, Grade 3 diarrhea occurred in 40% and Grade 4 diarrhea occurred in 0.1% of patients. The majority of patients (93%) had diarrhea in the first month of treatment, the median time to first onset of Grade ≥3 diarrhea was 8 days (range, 1–350), and the median cumulative duration of Grade ≥3 diarrhea was 5 days (range, 1–139) [see Adverse Reactions ( 6.1 )] . Diarrhea was reported in 83% of NERLYNX plus capecitabine treated patients in NALA, a randomized placebo-controlled trial in the metastatic breast cancer setting who were required to receive anti-diarrheal prophylaxis in the first 21-day cycle. The majority of patients (70%) had diarrhea in the first 21 days of treatment, the median time to first onset of Grade ≥3 diarrhea was 11 days (range, 2–728) and the median cumulative duration of Grade ≥3 diarrhea was 3 days (range, 1–21). In the NERLYNX plus capecitabine arm, Grade 3 diarrhea occurred in 24% of patients [see Adverse Reactions ( 6.1 )] . Antidiarrheal prophylaxis has been shown to lower the incidence and severity of diarrhea. Instruct patients to initiate antidiarrheal prophylaxis with loperamide along with the first dose of NERLYNX and continue during the first 56 days of treatment; after day 56, titrate dose to achieve 1–2 bowel movements per day and not to exceed 16 mg loperamide per day [see Dosage and Administration ( 2.1 )] . Consider adding other agents to loperamide as clinically indicated [see Adverse Reactions ( 6.1 )] . Alternatively, a 2-week NERLYNX dose escalation approach prior to initiation of the recommended treatment regimen with NERLYNX can also be considered for diarrhea management [see Dosage and Administration ( 2.2 )]. For patients who used NERLYNX dose escalation, the median time to first onset of Grade ≥3 diarrhea was 45 days (range, 15–132) and the median cumulative duration of Grade ≥3 diarrhea was 2.5 days (range, 1–6). Grade 3 diarrhea occurred in 13% of patients who used NERLYNX dose escalation [see Adverse Reactions ( 6.1 )]. Monitor patients for diarrhea and treat with additional antidiarrheals as needed. When severe diarrhea with dehydration occurs, administer fluid and electrolytes as needed, interrupt NERLYNX, and reduce subsequent doses [see Dosage and Administration ( 2.3 )] . Perform stool cultures as clinically indicated to exclude infectious causes of Grade 3 or 4 diarrhea or diarrhea of any grade with complicating features (dehydration, fever, neutropenia).

5.2 Hepatotoxicity NERLYNX has been associated with hepatotoxicity characterized by increased liver enzymes. In ExteNET, 10% of patients experienced an alanine aminotransferase (ALT) increase ≥2× ULN, 5% of patients experienced an aspartate aminotransferase (AST) increase ≥2× ULN, and 1.7% of patients experienced an AST or ALT increase >5× ULN (≥Grade 3). Hepatotoxicity or increases in liver transaminases led to drug discontinuation in 1.7% of NERLYNX-treated patients. In the NALA study, in NERLYNX and capecitabine-treated patients, 7% experienced an ALT or AST increase >3× ULN, 2% experienced an ALT or AST increase >5× ULN, 7% experienced a bilirubin increase >1.5× ULN, and 1.3% experienced a bilirubin increase >3× ULN. Hepatotoxicity or increases in liver transaminases led to drug discontinuation in 0.3% of NERLYNX and capecitabine-treated patients. Total bilirubin, AST, ALT, and alkaline phosphatase should be measured prior to starting treatment with NERLYNX monthly for the first 3 months of treatment, then every 3 months while on treatment and as clinically indicated. These tests should also be performed in patients experiencing Grade 3 diarrhea or any signs or symptoms of hepatotoxicity, such as worsening of fatigue, nausea, vomiting, right upper quadrant tenderness, fever, rash, or eosinophilia [see Dosage and Administration ( 2.3 ) and Adverse Reactions ( 6.1 )] .

5.3 Embryo-Fetal Toxicity Based on findings from animal studies and its mechanism of action, NERLYNX can cause fetal harm when administered to a pregnant woman. In animal reproduction studies, administration of neratinib to pregnant rabbits during organogenesis caused abortions, embryo-fetal death, and fetal abnormalities in rabbits at maternal AUCs approximately 0.2 times the AUC in patients receiving the recommended dose. Advise pregnant women of the potential risk to a fetus. Advise females of reproductive potential to use effective contraception during treatment and for at least 1 month after the last dose. [see Use in Specific Populations ( 8.1 , 8.3 ) and Clinical Pharmacology ( 12.1 )] .

The following clinically significant adverse reactions are described elsewhere in the labeling: Diarrhea [see Warnings and Precautions ( 5.1 )] Hepatotoxicity [see Warnings and Precautions ( 5.2 )] The most common adverse reactions (reported in ≥5% of patients) were: NERLYNX as a single agent: diarrhea, nausea, abdominal pain, fatigue, vomiting, rash, stomatitis, decreased appetite, muscle spasms, dyspepsia, AST or ALT increased, nail disorder, dry skin, abdominal distention, epistaxis, weight decreased, and urinary tract infection. ( 6 ) NERLYNX in combination with capecitabine: diarrhea, nausea, vomiting, decreased appetite, constipation, fatigue/asthenia, weight decreased, dizziness, back pain, arthralgia, urinary tract infection, upper respiratory tract infection, abdominal distention, renal impairment, and muscle spasms. ( 6 ) To report SUSPECTED ADVERSE REACTIONS, contact Puma Biotechnology, Inc. at 1-844-NERLYNX (1-844-637-5969) 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 directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. Extended Adjuvant Treatment of Early-Stage Breast Cancer ExteNET The data described below reflect the safety data of NERLYNX as a single agent in ExteNET, a multicenter, randomized, double-blind, placebo-controlled study of NERLYNX within 2 years after completion of adjuvant treatment with trastuzumab-based therapy in women with HER2-positive early-stage breast cancer. Patients who received NERLYNX in this trial were not required to receive any prophylaxis with antidiarrheal agents to prevent the NERLYNX-related diarrhea. Patients were treated with 240 mg of NERLYNX given orally once daily with food, continuously until disease recurrence or for up to one year. The median duration of treatment was 11.6 months in the NERLYNX arm and 11.8 months in the placebo arm. The median age was 52 years (60% were ≥50 years old, 12% were ≥65 years old); 81% were Caucasian, 3% Black or African American, 14% Asian, and 3% other. A total of 1408 patients were treated with NERLYNX. NERLYNX dose reduction due to an adverse reaction of any grade occurred in 31% of patients receiving NERLYNX compared to 2.6% of patients receiving placebo. Permanent discontinuation due to any adverse reaction was reported in 28% of NERLYNX-treated patients. The most common adverse reaction leading to discontinuation was diarrhea, accounting for 17% of NERLYNX-treated patients. The most common adverse reactions (≥5%) were diarrhea, nausea, abdominal pain, fatigue, vomiting, rash, stomatitis, decreased appetite, muscle spasms, dyspepsia, AST or ALT increased, nail disorder, dry skin, abdominal distention, epistaxis, weight decreased, and urinary tract infection. The most frequently reported Grade 3 or 4 adverse reactions were diarrhea, vomiting, nausea, and abdominal pain. Serious adverse reactions in the NERLYNX arm included diarrhea (1.6%), vomiting (0.9%), dehydration (0.6%), cellulitis (0.4%), renal failure (0.4%), erysipelas (0.4%), ALT increased (0.3%), AST increased (0.3%), nausea (0.3%), fatigue (0.2%), and abdominal pain (0.2%). Table 7 summarizes the adverse reactions in ExteNET. Table 7: Adverse Reactions Reported in ≥2% of NERLYNX-Treated Patients in ExteNET * Includes abdominal pain, abdominal pain upper, and abdominal pain lower † Includes stomatitis, aphthous stomatitis, mouth ulceration, oral mucosal blistering, mucosal inflammation, oropharyngeal pain, oral pain, glossodynia, glossitis, and cheilitis ‡ Includes rash, rash erythematous, rash follicular, rash generalized, rash pruritic, rash pustular, rash maculo-papular, rash papular, dermatitis, dermatitis acneiform, and toxic skin eruption § Includes nail disorder, paronychia, onychoclasis, nail discoloration, nail toxicity, nail growth abnormal, and nail dystrophy System Organ Class (Preferred Term) NERLYNX n=1408 Placebo n=1408 All Grades (%) Grade 3 (%) Grade 4 (%) All Grades (%) Grade 3 (%) Grade 4 (%) Gastrointestinal Disorders Diarrhea 95 40 0.1 35 2 0 Nausea 43 2 0 22 0.1 0 Abdominal pain * 36 2 0 15 0.4 0 Vomiting 26 3 0 8 0.4 0 Stomatitis † 14 0.6 0 6 0.1 0 Dyspepsia 10 0.4 0 4 0 0 Abdominal distension 5 0.3 0 3 0 0 Dry mouth 3 0.1 0 2 0 0 General Disorders and Administration Site Conditions Fatigue 27 2 0 20 0.4 0 Hepatobiliary Disorders Alanine aminotransferase increased 9 1 0.2 3 0.2 0 Aspartate aminotransferase increased 7 0.5 0.2 3 0.3 0 Infections and Infestations Urinary tract infection 5 0.1 0 2 0 0 Investigations Weight decreased 5 0.1 0 0.5 0 0 Metabolism and Nutrition Disorders Decreased appetite 12 0.2 0 3 0 0 Dehydration 4 0.9 0.1 0.4 0.1 0 Musculoskeletal and Connective Tissue Disorders Muscle spasms 11 0.1 0 3 0.1 0 Respiratory, Thoracic and Mediastinal Disorders Epistaxis 5 0 0 1 0.1 0 Skin and Subcutaneous Tissue Disorders Rash ‡ 18 0.6 0 9 0 0 Dry skin 6 0 0 2 0 0 Nail disorder § 8 0.3 0 2 0 0 Skin fissures 2 0.1 0 0.1 0 0 Advanced or Metastatic Breast Cancer NALA The data described below reflect the safety data of NERLYNX plus capecitabine in NALA, a randomized, multicenter, multinational, open-label, active-controlled study of HER2-positive metastatic breast cancer in patients, with or without brain metastases, who have received two or more prior anti HER2-based regimens in the metastatic setting. Patients were treated with NERLYNX 240 mg orally once daily Days 1–21 of a 21-day cycle in combination with capecitabine (750 mg/m 2 given orally twice daily) Days 1–14 of a 21-day cycle, or lapatinib 1250 mg orally once daily Days 1–21 of a 21-day cycle in combination with capecitabine (1000 mg/m 2 given orally twice daily) Days 1–14 of a 21-day cycle until disease progression. The median duration of treatment was 5.7 months in the NERLYNX plus capecitabine arm and 4.4 months in the lapatinib plus capecitabine arm. NERLYNX dose reduction due to an adverse reaction of any grade occurred in 10% of patients receiving NERLYNX plus capecitabine. Permanent discontinuation due to any adverse reaction was reported in 14% of NERLYNX plus capecitabine treated patients. The most common adverse reactions leading to discontinuation were vomiting (3.6%), diarrhea (2.6%), nausea (2.6%), and palmar-plantar erythrodysaesthesia syndrome (2.3%) of NERLYNX plus capecitabine-treated patients. The most common adverse reactions of any grade (≥5%) in the NERLYNX plus capecitabine arm were diarrhea, nausea, vomiting, decreased appetite, constipation, fatigue/asthenia, weight decreased, dizziness, back pain, arthralgia, urinary tract infection, upper respiratory tract infection, abdominal distention, renal impairment, and muscle spasms. The most frequently reported Grade 3 or 4 adverse reactions were diarrhea, nausea, vomiting, fatigue, and decreased appetite. Serious adverse reactions ≥2% in the NERLYNX plus capecitabine arm included diarrhea (7%), vomiting (3%), nausea (2.3%), and acute kidney injury (2.3%). Table 8 summarizes the adverse reactions in NALA. Table 8: Adverse Reactions Reported in ≥2% of NERLYNX-Treated Patients in Combination with Capecitabine in NALA * Renal impairment includes acute kidney injury, blood creatinine increased, renal failure, and renal impairment. […]

Gastric acid reducing agents: Avoid concomitant use with proton pump inhibitors. Separate NERLYNX by at least 2 hours before or 10 hours after H 2 -receptor antagonists. Or separate NERLYNX by at least 3 hours after antacids. ( 2.5 , 7.1 ) Strong CYP3A4 inhibitors: Avoid concomitant use. ( 7.1 ) P-gp and moderate CYP3A4 dual inhibitors: Avoid concomitant use. ( 7.1 ) Strong or moderate CYP3A4 inducers: Avoid concomitant use. ( 7.1 ) Certain P-gp substrates: Monitor for adverse reactions of P-gp substrates for which minimal concentration change may lead to serious adverse reactions when used concomitantly with NERLYNX. ( 7.2 )

7.1 Effect of Other Drugs on NERLYNX Table 10 includes drug interactions that affect the pharmacokinetics of neratinib. Table 10: Drug Interactions that Affect NERLYNX AUC=Area Under Curve; C max =Maximum Concentration Gastric Acid Reducing Agents Clinical Impact Concomitant use of NERLYNX with a proton pump inhibitor (PPI), H 2 -receptor antagonist, or antacid may decrease neratinib AUC [see Clinical Pharmacology ( 12.3 )], which may reduce NERLYNX activity. Prevention or Management [see Dosage and Administration ( 2.5 )] Avoid concomitant use of PPIs. Separate administration of NERLYNX at least 2 hours before or 10 hours after the H 2 -receptor antagonist dose. Separate administration of NERLYNX by at least 3 hours after antacids. Strong CYP3A4 Inhibitors Clinical Impact Concomitant use of NERLYNX with a strong CYP3A4 inhibitor increased neratinib C max and AUC [see Clinical Pharmacology ( 12.3 )] , which may increase the risk of NERLYNX toxicity. Prevention or Management Avoid concomitant use of NERLYNX with strong CYP3A4 inhibitors. P-gp and Moderate CYP3A4 Dual Inhibitors Clinical Impact Concomitant use of NERLYNX with a P-gp and moderate CYP3A4 dual inhibitor may increase neratinib C max and AUC [see Clinical Pharmacology ( 12.3 )] , which may increase the risk of NERLYNX toxicity. Prevention or Management Avoid concomitant use of NERLYNX with P-gp and moderate CYP3A4 dual inhibitors. Strong or Moderate CYP3A4 Inducers Clinical Impact Concomitant use of NERLYNX with a strong CYP3A4 inducer reduced neratinib C max and AUC [see Clinical Pharmacology ( 12.3 )] , which may reduce NERLYNX activity. Prevention or Management Avoid concomitant use of NERLYNX with strong or moderate CYP3A4 inducers.

7.2 Effect of NERLYNX on Other Drugs Certain P-glycoprotein (P-gp) Substrates Concomitant use of NERLYNX increased concentrations of a P-gp substrate [see Clinical Pharmacology ( 12.3 )] , which may increase the risk of adverse reactions of these substrates. Monitor for adverse reactions of certain P-gp substrates for which minimal concentration changes may lead to serious adverse reactions.

Lactation: Advise women not to breastfeed. ( 8.2 )

8.1 Pregnancy Risk Summary Based on findings from animal studies and the mechanism of action, NERLYNX can cause fetal harm when administered to a pregnant woman [see Clinical Pharmacology ( 12.1 )] . There are no available data in pregnant women to inform the drug-associated risk. In animal reproduction studies, administration of neratinib to pregnant rabbits during organogenesis resulted in abortions, embryo-fetal death and fetal abnormalities in rabbits at maternal exposures (AUC) approximately 0.2 times exposures in patients at the recommended dose ( see Data ). Advise pregnant women of the potential risk to a fetus. The background risk of major birth defects and miscarriage for the indicated population is unknown. However, the background risk of major birth defects is 2%–4% and of miscarriage is 15%–20% of clinically recognized pregnancies in the U.S. general population. Data Animal Data In a fertility and early embryonic development study in female rats, neratinib was administered orally for 15 days before mating to Day 7 of pregnancy, which did not cause embryonic toxicity at doses up to 12 mg/kg/day in the presence of maternal toxicity. A dose of 12 mg/kg/day in rats is approximately 0.5 times the maximum recommended dose of 240 mg/day in patients on a mg/m 2 basis. In an embryo-fetal development study in rats, pregnant animals received oral doses of neratinib up to 15 mg/kg/day during the period of organogenesis. No effects on embryo-fetal development or survival were observed. Maternal toxicity was evident at 15 mg/kg/day (approximately 0.6 times the AUC in patients receiving the maximum recommended dose of 240 mg/day). In an embryo-fetal development study in rabbits, pregnant animals received oral doses of neratinib up to 9 mg/kg/day during the period of organogenesis. Administration of neratinib at doses ≥6 mg/kg/day resulted in maternal toxicity, abortions, and embryo-fetal death (increased resorptions). Neratinib administration resulted in increased incidence of fetal gross external (domed head), soft tissue (dilation of the brain ventricles and ventricular septal defect), and skeletal (misshapen anterior fontanelles and enlarged anterior and/or posterior fontanelles) abnormalities at ≥3 mg/kg/day. The AUC (0-t) at 6 mg/kg/day and 9 mg/kg/day in rabbits were approximately 0.5 and 0.8 times, respectively, the AUCs in patients receiving the maximum recommended dose of 240 mg/day. In a peri- and postnatal development study in rats, oral administration of neratinib from gestation day 7 until lactation day 20 resulted in maternal toxicity at ≥10 mg/kg/day (approximately 0.4 times the maximum recommended dose of 240 mg/day in patients on a mg/m 2 basis) including decreased body weights, body weight gains, and food consumption. Effects on long-term memory were observed in male offspring at maternal doses ≥5 mg/kg/day (approximately 0.2 times the maximum recommended dose of 240 mg/day in patients on a mg/m 2 basis).

8.2 Lactation Risk Summary No data are available regarding the presence of neratinib or its metabolites in human milk or its effects on the breastfed infant or on milk production. Because of the potential for serious adverse reactions in breastfed infants from NERLYNX, advise lactating women not to breastfeed while taking NERLYNX and for at least 1 month after the last dose.

8.3 Females and Males of Reproductive Potential Pregnancy Based on animal studies, NERLYNX can cause fetal harm when administered to a pregnant woman [see Use in Specific Populations ( 8.1 )] . Females of reproductive potential should have a pregnancy test prior to starting treatment with NERLYNX. Contraception Females Based on animal studies, NERLYNX can cause fetal harm when administered to a pregnant woman [see Use in Specific Populations ( 8.1 )] . Advise females of reproductive potential to use effective contraception during treatment with NERLYNX and for at least 1 month after the last dose. Males Based on findings in animal reproduction studies, advise male patients with female partners of reproductive potential to use effective contraception during treatment and for 3 months after the last dose of NERLYNX [see Use in Specific Populations ( 8.1 )] .

8.4 Pediatric Use The safety and efficacy of NERLYNX in pediatric patients has not been established.

8.5 Geriatric Use In the ExteNET trial, in the NERLYNX arm; 1236 patients were <65 years, 172 patients were ≥65 years, of whom 25 patients were 75 years or older. There was a higher frequency of treatment discontinuations due to adverse reactions in the ≥65 years age group than in the <65 years age group; in the NERLYNX arm, the percentages were 45% compared with 25%, respectively, and in the placebo arm 6% and 5%, respectively. The incidence of serious adverse reactions in the NERLYNX arm vs placebo arm was 7% vs 6% (<65 years old) and 10% vs 8% (≥65 years old). The serious adverse reactions most frequently reported in the ≥65 years old group were vomiting (2.3%), diarrhea (1.7%), renal failure (1.7%), and dehydration (1.2%). In the NALA trial, in the NERLYNX plus capecitabine arm; 242 patients were <65 years, 61 patients were ≥65 years, of whom 12 patients were 75 years or older. The incidence of serious adverse reactions in the NERLYNX plus capecitabine arm in the ≥65 years age group was 36% and in the <65 years age group was 34%. The serious adverse reactions most frequently reported in the ≥65 years age group were diarrhea (16%), acute kidney injury (8%), and dehydration (7%). No overall differences in effectiveness were observed between patients ≥65 years old and patients <65 years old.

8.6 Hepatic Impairment No dosage modifications are recommended for patients with mild to moderate hepatic impairment (Child Pugh A or B). Neratinib clearance is reduced, and C max and AUC increase in patients with severe, pre-existing hepatic impairment (Child Pugh C). Reduce the NERLYNX dosage for patients with severe hepatic impairment [see Dosage and Administration ( 2.4 ) and Clinical Pharmacology ( 12.3 )] .

Neratinib is an intracellular kinase inhibitor that irreversibly binds to epidermal growth factor receptor (EGFR), HER2, and HER4. In vitro , neratinib reduces EGFR and HER2 autophosphorylation, downstream MAPK and AKT signaling pathways, and showed antitumor activity in EGFR and/or HER2 expressing carcinoma cell lines. Neratinib human metabolites M3, M6, M7 and M11 inhibited the activity of EGFR, HER2, and HER4 in vitro. In vivo , oral administration of neratinib inhibited tumor growth in mouse xenograft models with tumor cell lines expressing HER2 and EGFR.