Maraviroc

5 WARNINGS AND PRECAUTIONS • Hepatotoxicity accompanied by severe rash or systemic allergic reaction, including potentially life-threatening events, has been reported. Hepatic laboratory parameters including ALT, AST, and bilirubin should be obtained prior to starting maraviroc tablets and at other time points during treatment as clinically indicated. If rash or symptoms or signs of hepatitis or allergic reaction develop, hepatic laboratory parameters should be monitored and discontinuation of treatment should be considered. When administering maraviroc tablets to patients with pre-existing liver dysfunction or who are co-infected with hepatitis B and/or C virus, additional monitoring may be warranted. ( 5.1 ) • Severe and potentially life-threatening skin and hypersensitivity reactions have been reported in patients taking maraviroc. This includes cases of Stevens-Johnson syndrome, hypersensitivity reaction, and toxic epidermal necrolysis. Immediately discontinue maraviroc and other suspected agents if signs or symptoms of severe skin or hypersensitivity reactions develop and monitor clinical status, including liver aminotransferases, closely. ( 5.2 ) • More cardiovascular events, including myocardial ischemia and/or infarction, were observed in treatment-experienced subjects who received maraviroc. Additional monitoring may be warranted. ( 5.3 ) • If patients with severe renal impairment or ESRD receiving maraviroc (without concomitant CYP3A inducers or inhibitors) experience postural hypotension, the dose of maraviroc should be reduced from 300 mg twice daily to 150 mg twice daily. ( 5.3 ) 5.1 Hepatotoxicity Hepatotoxicity with allergic features including life-threatening events has been reported in clinical trials and postmarketing. Severe rash or evidence of systemic allergic reaction including drug-related rash with fever, eosinophilia, elevated IgE, or other systemic symptoms have been reported in conjunction with hepatotoxicity [ see Warnings and Precautions ( 5.2 ) ]. These events occurred approximately 1 month after starting treatment. Among reported cases of hepatitis, some were observed in the absence of allergic features or with no pre-existing hepatic disease. Appropriate laboratory testing including ALT, AST, and bilirubin should be conducted prior to initiating therapy with maraviroc and at other time points during treatment as clinically indicated. Hepatic laboratory parameters should be obtained in any patient who develops rash, or signs or symptoms of hepatitis, or allergic reaction. Discontinuation of maraviroc should be considered in any patient with signs or symptoms of hepatitis, or with increased liver transaminases combined with rash or other systemic symptoms. When administering maraviroc to patients with pre-existing liver dysfunction or who are co-infected with hepatitis B and/or C virus, additional monitoring may be warranted. The safety and efficacy of maraviroc have not been specifically studied in patients with significant underlying liver disorders. 5.2 Severe Skin and Hypersensitivity Reactions Severe, potentially life-threatening skin and hypersensitivity reactions have been reported in patients taking maraviroc, in most cases concomitantly with other drugs associated with these reactions. These include cases of Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), and drug rash with eosinophilia and systemic symptoms (DRESS) [ see Adverse Reactions (6.3) ]. The cases were characterized by features including rash, constitutional findings, and sometimes organ dysfunction, including hepatic failure. Discontinue maraviroc and other suspected agents immediately if signs or symptoms of severe skin or hypersensitivity reactions develop (including, but not limited to, severe rash or rash accompanied by fever, malaise, muscle or joint aches, blisters, oral lesions, conjunctivitis, facial edema, lip swelling, eosinophilia). Delay in stopping treatment with maraviroc or other suspect drugs after the onset of rash may result in a life-threatening reaction. Clinical status, including liver aminotransferases, should be monitored and appropriate therapy initiated. 5.3 Cardiovascular Events Eleven subjects (1.3%) who received maraviroc had cardiovascular events, including myocardial ischemia and/or infarction, during the Phase 3 trials in treatment-experienced subjects (total exposure 609 patient-years [300 on maraviroc once daily + 309 on maraviroc twice daily]), while no subjects who received placebo had such events (total exposure 111 patient-years). These subjects generally had cardiac disease or cardiac risk factors prior to use of maraviroc, and the relative contribution of maraviroc to these events is not known. In the Phase 2b/3 trial in treatment-naive adult subjects, 3 subjects (0.8%) who received maraviroc had events related to ischemic heart disease and 5 subjects (1.4%) who received efavirenz had such events (total exposure 506 and 508 patient-years for maraviroc and efavirenz, respectively). When maraviroc was administered to healthy volunteers at doses higher than the recommended dose, symptomatic postural hypotension was seen at a greater frequency than in placebo. However, when maraviroc was given at the recommended dose in HIV-1-infected adult subjects in Phase 3 trials, postural hypotension was seen at a rate similar to placebo (approximately 0.5%). Patients with cardiovascular comorbidities, risk factors for postural hypotension, or receiving concomitant medication known to lower blood pressure, could be at increased risk of cardiovascular adverse events triggered by postural hypotension. Additional monitoring may be warranted. Postural Hypotension in Patients with Renal Impairment An increased risk of postural hypotension may occur in patients with severe renal insufficiency or in those with ESRD due to increased maraviroc exposure in some patients. Maraviroc should be used in patients with severe renal impairment or ESRD only if they are not receiving a concomitant potent CYP3A inhibitor or inducer. However, the use of maraviroc in these patients should only be considered when no alternative treatment options are available. If adult patients with severe renal impairment or ESRD experience any symptoms of postural hypotension while taking 300 mg twice daily, the dose should be reduced to 150 mg twice daily [ see Dosage and Administration ( 2.5 ) ]. 5.4 Immune Reconstitution Syndrome Immune reconstitution syndrome has been reported in patients treated with combination antiretroviral therapy, including maraviroc. During the initial phase of combination antiretroviral treatment, patients whose immune systems respond may develop an inflammatory response to indolent or residual opportunistic infections (such as infection with Mycobacterium avium infection, cytomegalovirus, Pneumocystis jirovecii pneumonia [PCP], tuberculosis, or reactivation of Herpes simplex and Herpes zoster ), which may necessitate further evaluation and treatment. Autoimmune disorders (such as Graves’ disease, polymyositis, and Guillain-Barré syndrome) have also been reported to occur in the setting of immune reconstitution; however, the time to onset is more variable, and can occur many months after initiation of treatment. 5.5 Potential Risk of Infection Maraviroc antagonizes the CCR5 co-receptor located on some immune cells, and therefore could potentially increase the risk of developing infections. The overall incidence and severity of infection, as well as AIDS-defining category C infections, were comparable in the treatment groups during the Phase 3 adult treatment-experienced trials of maraviroc. While there was a higher rate of certain upper respiratory tract infections reported in the treatment arm receiving maraviroc compared with placebo (23% versus 13%), there was a lower rate of pneumonia (2% versus 5%) reported in subjects receiving maraviroc. A higher incidence of Herpes virus infections (11 per 100 patient-years) was also reported in the treatment arm receiving maraviroc when adjusted for exposure compared with placebo (8 per 100 patient-years). In the Phase 2b/3 trial in treatment-naive adult subjects, the incidence of AIDS-defining Category C events when adjusted for exposure was 1.8 for maraviroc compared with 2.4 for efavirenz per 100 patient-years of exposure. Patients should be monitored closely for evidence of infections while receiving maraviroc. 5.6 Potential Risk of Malignancy While no increase in malignancy has been observed with maraviroc, due to this drug’s mechanism of action, it could affect immune surveillance and lead to an increased risk of malignancy. The exposure-adjusted rate for malignancies per 100 patient-years of exposure in adult treatment-experienced trials was 4.6 for maraviroc compared with 9.3 on placebo. In treatment-naive adult subjects, the rates were 1.0 and 2.4 per 100 patient-years of exposure for maraviroc and efavirenz, respectively. Long-term follow-up is needed to more fully assess this risk.

6 ADVERSE REACTIONS The following adverse reactions are discussed in other sections of the labeling: • Hepatotoxicity [ see Boxed Warning, Warnings and Precautions ( 5.1 ) ] • Severe Skin and Hypersensitivity Reactions [ see Warnings and Precautions ( 5.2 ) ] • Cardiovascular Events [ see Warnings and Precautions ( 5.3 ) ] • The most common adverse events in treatment-experienced adult subjects (greater than 8% incidence) which occurred at a higher frequency compared with placebo are upper respiratory tract infections, cough, pyrexia, rash, and dizziness. ( 6.1 ) • The most common adverse events in treatment-naive adult subjects (greater than 8% incidence) which occurred at a higher frequency than the comparator arm are upper respiratory tract infections, bronchitis, flatulence, bloating and distention, upper respiratory tract signs and symptoms, and gastrointestinal atonic and hypomotility disorders. ( 6.1 ) • The most common adverse reactions in treatment-experienced pediatric subjects (greater than or equal to 3% incidence) are vomiting, abdominal pain, diarrhea, nausea, and dizziness. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Hetero Labs Limited at 1-866-495-1995 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 with rates in the clinical trials of another drug and may not reflect the rates observed in practice. Clinical Trials Experience in Adult Subjects Treatment-Experienced Subjects: The safety profile of maraviroc is primarily based on 840 HIV-1-infected subjects who received at least 1 dose of maraviroc during two Phase 3 trials. A total of 426 of these subjects received the indicated twice-daily dosing regimen. Assessment of treatment-emergent adverse events is based on the pooled data from 2 trials in subjects with CCR5-tropic HIV-1 (A4001027 and A4001028). The median duration of therapy with maraviroc for subjects in these trials was 48 weeks, with the total exposure on maraviroc twice daily at 309 patient-years versus 111 patient-years on placebo each administered with optimized background therapy (OBT). The population was 89% male and 84% white, with mean age of 46 years (range: 17 to 75 years). Subjects received dose equivalents of 300 mg maraviroc once or twice daily. The most common adverse events reported with twice-daily therapy with maraviroc with frequency rates higher than placebo, regardless of causality, were upper respiratory tract infections, cough, pyrexia, rash, and dizziness. In these 2 trials, the rate of discontinuation due to adverse events was 5% for subjects who received maraviroc twice daily + OBT as well as those who received placebo + OBT. Most of the adverse events reported were judged to be mild to moderate in severity. The data described below occurred with twice-daily dosing of maraviroc. The total numbers of subjects reporting infections were 233 (55%) and 84 (40%) in the group receiving maraviroc twice daily and the placebo group, respectively. Correcting for the longer duration of exposure on maraviroc compared with placebo, the exposure-adjusted frequency (rate per 100 subject-years) of these events was 133 for both maraviroc twice daily and placebo. Dizziness or postural dizziness occurred in 8% of subjects on either maraviroc or placebo, with 2 subjects (0.5%) on maraviroc permanently discontinuing therapy (1 due to syncope, 1 due to orthostatic hypotension) versus 1 subject on placebo (0.5%) permanently discontinuing therapy due to dizziness. Treatment-emergent adverse events, regardless of causality, from Trials A4001027 and A4001028 are summarized in Table 5. Selected events occurring at greater than or equal to 2% of subjects and at a numerically higher rate in subjects treated with maraviroc are included; events that occurred at the same or higher rate on placebo are not displayed. Table 5. Selected Treatment-Emergent Adverse Events (All Causality) ≥2% on Maraviroc (and at a Higher Rate Compared with Placebo) in Trials A4001027 and A4001028 (Pooled Analysis, 48 Weeks) Body System/ Adverse Event Maraviroc Twice Daily a Placebo (n = 426) % Exposure-Adjusted Rate (per 100 pt-yrs) PYE=309 b (n = 209) % Exposure-Adjusted Rate (per 100 pt-yrs) PYE=111 b Eye Disorders Conjunctivitis 2 3 1 3 Ocular infections, inflammations, and associated manifestations 2 3 1 2 Gastrointestinal Disorders Constipation 6 9 3 6 General Disorders and Administration Site Conditions Pyrexia 13 20 9 17 Pain and discomfort 4 5 3 5 Infections and Infestations Upper respiratory tract infection 23 37 13 27 Herpes infection 8 11 4 8 Sinusitis 7 10 3 6 Bronchitis 7 9 5 9 Folliculitis 4 5 2 4 Anogenital warts 2 3 1 3 Influenza 2 3 0.5 1 Otitis media 2 3 0.5 1 Metabolism and Nutrition Disorders Appetite disorders 8 11 7 13 Musculoskeletal and Connective Tissue Disorders Joint-related signs and symptoms 7 10 3 5 Muscle pains 3 4 0.5 1 Neoplasms Benign, Malignant, and Unspecified Skin neoplasms benign 3 4 1 3 Nervous System Disorders Dizziness/postural dizziness 9 13 8 17 Paresthesias and dysesthesias 5 7 3 6 Sensory abnormalities 4 6 1 3 Disturbances in consciousness 4 5 3 6 Peripheral neuropathies 4 5 3 6 Psychiatric Disorders Disturbances in initiating and maintaining sleep 8 11 5 10 Depressive disorders 4 6 3 5 Anxiety symptoms 4 5 3 7 Renal and Urinary Disorders Bladder and urethral symptoms 5 7 1 3 Urinary tract signs and symptoms 3 4 1 3 Respiratory, Thoracic, and Mediastinal Disorders Coughing and associated symptoms 14 21 5 10 Upper respiratory tract signs and symptoms 6 9 3 6 Nasal congestion and inflammations 4 6 3 5 Breathing abnormalities 4 5 2 5 Paranasal sinus disorders 3 4 0.5 1 Skin and Subcutaneous Tissue Disorders Rash 11 16 5 11 Apocrine and eccrine gland disorders 5 7 4 7.5 Pruritus 4 5 2 4 Lipodystrophies 3 5 0.5 1 Erythema 2 3 1 2 Vascular Disorders Vascular hypertensive disorders 3 4 2 4 a 300-mg dose equivalent. b PYE = Patient-years of exposure. Laboratory Abnormalities: Table 6 shows the treatment-emergent Grade 3 to 4 laboratory abnormalities that occurred in greater than 2% of subjects receiving maraviroc. Table 6. Maximum Shift in Laboratory Test Values (without Regard to Baseline) ≥2% of Grade 3 to 4 Abnormalities (ACTG Criteria) in Trials A4001027 and A4001028 (Pooled Analysis, 48 Weeks) Laboratory Parameter Preferred Term Limit Maraviroc Twice Daily + OBT (n = 421) a % Placebo + OBT (n = 207) a % Aspartate aminotransferase >5.0 x ULN 4.8 2.9 Alanine aminotransferase >5.0 x ULN 2.6 3.4 Total bilirubin >2.5 x ULN 5.5 5.3 Amylase >2.0 x ULN 5.7 5.8 Lipase >2.0 x ULN 4.9 6.3 Absolute neutrophil count 5.0 x ULN 4.0 4.0 Alanine aminotransferase >5.0 x ULN 3.9 4.0 Creatine kinase >10.0 x ULN 3.9 4.8 Amylase >2.0 x ULN 4.3 6.0 Absolute neutrophil count <750/mm 3 5.7 4.9 Hemoglobin <7.0 g/dL 2.9 2.3 ULN = Upper limit of normal. a n = Total number of subjects evaluable for laboratory abnormalities. Percentages based on total subjects evaluated for each laboratory parameter. If the same subject in a given treatment group had greater than 1 occurrence of the same abnormality, only the most severe is counted. Less Common Adverse Events in Clinical Trials: The following adverse events occurred in less than 2% of subjects treated with maraviroc or at a rate similar to the comparator. These events have been included because of their seriousness and either increased frequency on maraviroc or are potential risks due to the mechanism of action. Events attributed to the subject’s underlying HIV-1 infection are not listed. Blood and Lymphatic System: Marrow depression and hypoplastic anemia. Cardiac Disorders: Unstable angina, acute cardiac failure, coronary artery disease, coronary artery occlusion, myocardial infarction, myocardial ischemia. Hepatobiliary Disorders: Hepatic cirrhosis, hepatic failure, cholestatic jaundice, portal vein thrombosis, jaundice. Infections and Infestations : Endocarditis, infective myositis, viral meningitis, pneumonia, treponema infections, septic shock, Clostridium difficile colitis, meningitis. Musculoskeletal and Connective Tissue Disorders: Myositis, osteonecrosis, rhabdomyolysis, blood CK increased. Neoplasms Benign, Malignant, and Unspecified (Including Cysts and Polyps): Abdominal neoplasm, anal cancer, basal cell carcinoma, Bowen’s disease, cholangiocarcinoma, diffuse large B-cell lymphoma, lymphoma, metastases to liver, esophageal carcinoma, nasopharyngeal carcinoma, squamous cell carcinoma, squamous cell carcinoma of skin, tongue neoplasm (malignant stage unspecified), anaplastic large cell lymphomas T- and null-cell types, bile duct neoplasms malignant, endocrine neoplasms malignant and unspecified. Nervous System Disorders: Cerebrovascular accident, convulsions and epilepsy, tremor (excluding congenital), facial palsy, hemianopia, loss of consciousness, visual field defect. Clinical Trials Experience in Pediatric Subjects HIV-1–Infected Pediatric Subjects: Trial A4001031 is an open-label trial in which 103 treatment-experienced, CCR5-tropic, HIV-1–infected pediatric subjects aged 2 to less than 18 years weighing at least 10 kg received maraviroc twice daily in combination with OBT. The dose of maraviroc was based on body surface area (BSA) and on whether the subject was receiving potent CYP3A inhibitors and/or inducers. The median duration of therapy with maraviroc was 131 weeks with 72% of subjects receiving study treatment for greater than 48 weeks and 62% of subjects receiving study treatment for 96 weeks. In these 103 children and adolescents, the safety profile through 96 weeks was similar to that for adults. Most of the adverse reactions reported were mild to moderate; severe (Grade 3 and 4) adverse reactions occurred in 2% of subjects. The most common adverse reactions (all grades) reported with twice-daily therapy with maraviroc were vomiting (12%), abdominal pain (4%), diarrhea (4%), nausea (4%), and dizziness (3%). Three subjects (3%) discontinued due to adverse events. Maraviroc-related gastrointestinal adverse events through 48 weeks (nausea, vomiting, diarrhea, constipation, and abdominal pain/cramps) were observed more commonly in subjects who received the maraviroc oral solution (21%) compared with those who received maraviroc tablets (16%). Subjects were permitted to change formulations after Week 48. 6.2 Postmarketing Experience The following adverse events have been identified during post-approval use of maraviroc. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. Skin and Subcutaneous Tissue Disorders Stevens-Johnson syndrome (SJS), drug rash with eosinophilia and systemic symptoms (DRESS), toxic epidermal necrolysis (TEN).

8 USE IN SPECIFIC POPULATIONS • Lactation: Women infected with HIV should be instructed not to breastfeed due to the potential for HIV transmission. ( 8.2 ) 8.1 Pregnancy Pregnancy Exposure Registry There is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to maraviroc during pregnancy. Physicians are encouraged to register patients by calling the Antiretroviral Pregnancy Registry (APR) at 1-800-258-4263. Risk Summary Limited data on the use of maraviroc during pregnancy from the APR and case reports are not sufficient to inform a drug-associated risk of birth defects and miscarriage. In animal reproduction studies, no evidence of adverse developmental outcomes was observed with maraviroc. During organogenesis in the rat and rabbit, systemic exposures (AUC) to maraviroc were approximately 20 times (rats) and 5 times (rabbits) the exposure in humans at the recommended 300-mg twice-daily dose. In the rat pre- and post-natal development study, maternal systemic exposure (AUC) to maraviroc was approximately 14 times the exposure in humans at the recommended 300-mg twice-daily dose ( see Data ). The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively. Data Animal Data: Maraviroc was administered orally to pregnant rats (up to 1,000 mg per kg per day) and rabbits (up to 75 mg per kg per day) on gestation Days 6 to 17 and 7 to 19, respectively. No adverse effects on embryo-fetal development were observed at these dose levels, resulting in exposures (AUC) approximately 20 times (rats) and 5 times (rabbits) higher than human exposures at the recommended daily dose. In the rat pre- and post-natal development study, maraviroc was administered orally at up to 1,000 mg per kg per day on gestation Day 6 to lactation/post-partum Day 20, with development of the offspring (including fertility and reproductive performance) unaffected by maternal administration of maraviroc at an exposure (AUC) approximately 14 times higher than human exposure at the recommended daily dose. 8.2 Lactation Risk Summary The Centers for Disease Control and Prevention recommend that HIV-1–infected mothers in the United States not breastfeed their infants to avoid risking postnatal transmission of HIV-1 infection. There are no data on the presence of maraviroc in human milk, the effects on the breastfed infant, or the effects on milk production. When administered to lactating rats, maraviroc was present in milk ( see Data ). Because of the potential for (1) HIV transmission (in HIV-negative infants), (2) developing viral resistance (in HIV-positive infants), and (3) serious adverse reactions in a breastfed infant similar to those seen in adults, instruct mothers not to breastfeed if they are receiving maraviroc. Data Maraviroc (and related metabolites) was excreted into the milk of lactating rats following a single oral dose of maraviroc (100 mg per kg) on lactation Day 12, with a maximal milk concentration achieved one hour post-administration at a milk concentration approximately 2.5 times that of maternal plasma concentrations. 8.4 Pediatric Use The safety and efficacy of maraviroc have been established in pediatric patients aged from aged 2 to less than 18 years. The use of maraviroc in pediatric patients was supported by pharmacokinetic and safety data described below and by previous demonstration of efficacy in adult patients [ see Indications and Usage (1)], Dosage and Administration ( 2.4 ) ]. HIV-1–Infected Pediatric Patients Aged 2 to Less Than 18 Years : The safety, pharmacokinetic profile, and antiviral activity of maraviroc were evaluated in treatment-experienced, CCR5- tropic, HIV-1–infected pediatric subjects aged 2 to less than 18 years weighing at least 10 kg in an open-label, multicenter clinical trial, A4001031 [ see Adverse Reactions ( 6.1 ), Clinical Studies ( 14.2 ) ]. Pharmacokinetics were evaluated in a total of 98 pediatric subjects: 85 subjects received maraviroc and concomitant medications that included potent CYP3A inhibitors with or without potent CYP3A inducers, 10 subjects received maraviroc and noninteracting medications (not containing potent CYP3A inhibitors or potent CYP3A inducers), and three subjects received maraviroc and medications that included potent CYP3A inducers without potent CYP3A inhibitors [ see Clinical Pharmacology ( 12.3 ) ]. There are insufficient data to make dosing recommendations for use of maraviroc in pediatric patients concomitantly receiving potent CYP3A inhibitors and weighing less than 10 kg, or in any pediatric patients concomitantly receiving potent CYP3A inducers without a potent CYP3A inhibitor [ see Dosage and Administration ( 2.4 , 2.5 ) ]. Maraviroc is not recommended in pediatric patients weighing less than 10 kg. 8.5 Geriatric Use There were insufficient numbers of subjects aged 65 and over in the clinical trials to determine whether they respond differently from younger subjects. In general, caution should be exercised when administering maraviroc in elderly patients, also reflecting the greater frequency of decreased hepatic and renal function, of concomitant disease and other drug therapies. 8.6 Renal Impairment Recommended doses of maraviroc for adult patients with impaired renal function (CrCl less than or equal to 80 mL per minute) are based on the results of a pharmacokinetic trial conducted in healthy adult subjects with various degrees of renal impairment. Maraviroc has not been studied in pediatric patients with renal impairment. There are no data to recommend specific doses of maraviroc in pediatric patients with mild to moderate renal impairment [ see Use in Specific Populations ( 8.4 ) ]. Maraviroc is contraindicated in pediatric patients with severe renal impairment or ESRD on regular hemodialysis who are receiving potent CYP3A inhibitors [ see Contraindications ( 4 ) ]. The pharmacokinetics of maraviroc in adult subjects with mild and moderate renal impairment was similar to that in subjects with normal renal function [ see Clinical Pharmacology ( 12.3 ) ]. A limited number of adult subjects with mild and moderate renal impairment in the Phase 3 clinical trials (n = 131 and n = 12, respectively) received the same dose of maraviroc as that administered to subjects with normal renal function. In these subjects, there was no apparent difference in the adverse event profile for maraviroc compared with subjects with normal renal function. If adult patients with severe renal impairment or ESRD not receiving a concomitant potent CYP3A inhibitor or inducer experience any symptoms of postural hypotension while taking maraviroc 300 mg twice daily, the dose should be reduced to 150 mg twice daily. No trials have been performed in subjects with severe renal impairment or ESRD co-treated with potent CYP3A inhibitors or inducers. Hence, no dose of maraviroc can be recommended, and maraviroc is contraindicated for these patients [ see Dosage and Administration ( 2.3 ), Contraindications ( 4 ), Warnings and Precautions ( 5.3 ), Clinical Pharmacology ( 12.3 ) ]. 8.7 Hepatic Impairment Maraviroc is principally metabolized by the liver; therefore, when administering this drug to patients with hepatic impairment, maraviroc concentrations may be increased. Maraviroc concentrations are higher when maraviroc 150 mg is administered with a potent CYP3A inhibitor compared with following administration of 300 mg without a CYP3A inhibitor, so patients with moderate hepatic impairment who receive maraviroc 150 mg with a potent CYP3A inhibitor should be monitored closely for maraviroc-associated adverse events. Maraviroc has not been studied in subjects with severe hepatic impairment or in pediatric patients with any degree of hepatic impairment [ see Warnings and Precautions ( 5.1 ), Clinical Pharmacology ( 12.3 ) ].

8.1 Pregnancy Pregnancy Exposure Registry There is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to maraviroc during pregnancy. Physicians are encouraged to register patients by calling the Antiretroviral Pregnancy Registry (APR) at 1-800-258-4263. Risk Summary Limited data on the use of maraviroc during pregnancy from the APR and case reports are not sufficient to inform a drug-associated risk of birth defects and miscarriage. In animal reproduction studies, no evidence of adverse developmental outcomes was observed with maraviroc. During organogenesis in the rat and rabbit, systemic exposures (AUC) to maraviroc were approximately 20 times (rats) and 5 times (rabbits) the exposure in humans at the recommended 300-mg twice-daily dose. In the rat pre- and post-natal development study, maternal systemic exposure (AUC) to maraviroc was approximately 14 times the exposure in humans at the recommended 300-mg twice-daily dose ( see Data ). The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively. Data Animal Data: Maraviroc was administered orally to pregnant rats (up to 1,000 mg per kg per day) and rabbits (up to 75 mg per kg per day) on gestation Days 6 to 17 and 7 to 19, respectively. No adverse effects on embryo-fetal development were observed at these dose levels, resulting in exposures (AUC) approximately 20 times (rats) and 5 times (rabbits) higher than human exposures at the recommended daily dose. In the rat pre- and post-natal development study, maraviroc was administered orally at up to 1,000 mg per kg per day on gestation Day 6 to lactation/post-partum Day 20, with development of the offspring (including fertility and reproductive performance) unaffected by maternal administration of maraviroc at an exposure (AUC) approximately 14 times higher than human exposure at the recommended daily dose.