Included as part of the "PRECAUTIONS" Section
Hepatotoxicity And Hepatic Impairment
Severe, life-threatening, and in some cases fatal hepatotoxicity, including fulminant and cholestatic hepatitis, hepatic necrosis and hepatic failure, have been reported in patients treated with nevirapine.
The risk of symptomatic hepatic events regardless of severity is greatest in the first 6 weeks of therapy. The risk continued to be greater in the nevirapine groups in controlled clinical trials through 18 weeks of treatment. However, hepatic events may occur at any time during treatment. In some cases, patients presented with nonspecific, prodromal signs or symptoms of fatigue, malaise, anorexia, nausea, jaundice, liver tenderness or hepatomegaly, with or without initially abnormal serum transaminase levels. Rash was observed in approximately half of the patients with symptomatic hepatic adverse events. Fever and flu-like symptoms accompanied some of these hepatic events. Some events, particularly those with rash and other symptoms, have progressed to hepatic failure with transaminase elevation, with or without hyperbilirubinemia, hepatic encephalopathy, prolonged partial thromboplastin time, or eosinophilia. Rhabdomyolysis has been observed in some patients experiencing skin and/or liver reactions associated with nevirapine use. Hepatitis/hepatic failure may be associated with signs of hypersensitivity which can include severe rash or rash accompanied by fever, general malaise, fatigue, muscle or joint aches, blisters, oral lesions, conjunctivitis, facial edema, eosinophilia, granulocytopenia, lymphadenopathy, or renal dysfunction. Patients with signs or symptoms of hepatitis must be advised to discontinue nevirapine and immediately seek medical evaluation, which should include liver enzyme tests.
The first 18 weeks of therapy with VIRAMUNE XR are a critical period during which intensive clinical and laboratory monitoring of patients is required to detect potentially life-threatening hepatic events. The optimal frequency of monitoring during this time period has not been established. Some experts recommend clinical and laboratory monitoring more often than once per month, and in particular, include monitoring of liver enzyme tests at baseline, prior to dose escalation and at two weeks post-dose escalation. After the initial 18-week period, frequent clinical and laboratory monitoring should continue throughout VIRAMUNE XR treatment.
Transaminases should be checked immediately if a patient experiences signs or symptoms suggestive of hepatitis and/or hypersensitivity reaction. Transaminases should also be checked immediately for all patients who develop a rash in the first 18 weeks of treatment. Physicians and patients should be vigilant for the appearance of signs or symptoms of hepatitis, such as fatigue, malaise, anorexia, nausea, jaundice, bilirubinuria, acholic stools, liver tenderness, or hepatomegaly. The diagnosis of hepatotoxicity should be considered in this setting, even if transaminases are initially normal or alternative diagnoses are possible [see DOSAGE AND ADMINISTRATION].
If clinical hepatitis or transaminase elevations combined with rash or other systemic symptoms occur, permanently discontinue nevirapine. Do not restart nevirapine after recovery. In some cases, hepatic injury progresses despite discontinuation of treatment.
The patients at greatest risk of hepatic events, including potentially fatal events, are women with high CD4+ cell counts. In a retrospective analysis of pooled clinical trials with immediate-release VIRAMUNE, during the first 6 weeks of treatment women had a 3-fold higher risk than men for symptomatic, often rash-associated, hepatic events (6% versus 2%). Patients with higher CD4+ cell counts at initiation of nevirapine therapy are at higher risk for symptomatic hepatic events. Women with CD4+ cell counts greater than 250 cells/mm3 had a 12-fold higher risk of symptomatic hepatic adverse events compared to women with CD4+ cell counts less than 250 cells/mm3 (11% versus 1%). An increased risk was observed in men with CD4+ cell counts greater than 400 cells/mm3 (6% versus 1% for men with CD4+ cell counts less than 400 cells/mm3). However, all patients, regardless of gender, CD4+ cell count, or antiretroviral treatment history, should be monitored for hepatotoxicity since symptomatic hepatic adverse events have been reported at all CD4+ cell counts. Co-infection with hepatitis B or C and/or increased transaminase elevations at the start of therapy with nevirapine are associated with a greater risk of later symptomatic events (6 weeks or more after starting nevirapine) and asymptomatic increases in AST or ALT.
In addition, serious hepatotoxicity (including liver failure requiring transplantation in one instance) has been reported in HIV-1 uninfected individuals receiving multiple doses of immediate-release VIRAMUNE in the setting of post-exposure prophylaxis (PEP), an unapproved use. Use of VIRAMUNE XR for occupational and non-occupational PEP is contraindicated [see CONTRAINDICATIONS].
Increased nevirapine trough concentrations have been observed in some patients with hepatic fibrosis or cirrhosis. Therefore, carefully monitor patients with either hepatic fibrosis or cirrhosis for evidence of drug-induced toxicity. Do not administer nevirapine to patients with moderate or severe (Child-Pugh Class B or C, respectively) hepatic impairment [see CONTRAINDICATIONS, Use In Specific Populations, and CLINICAL PHARMACOLOGY]. VIRAMUNE XR has not been evaluated in subjects with hepatic impairment.
Severe and life-threatening skin reactions, including fatal cases, have been reported in patients taking nevirapine. These have occurred most frequently during the first 6 weeks of therapy. These have included cases of Stevens-Johnson syndrome, toxic epidermal necrolysis, and hypersensitivity reactions characterized by rash, constitutional findings, and organ dysfunction including hepatic failure. Rhabdomyolysis has been observed in some patients experiencing skin and/or liver reactions associated with nevirapine use.
Patients developing signs or symptoms of severe skin reactions or hypersensitivity reactions (including, but not limited to, severe rash or rash accompanied by fever, general malaise, fatigue, muscle or joint aches, blisters, oral lesions, conjunctivitis, facial edema, and/or hepatitis, eosinophilia, granulocytopenia, lymphadenopathy, and renal dysfunction) must permanently discontinue nevirapine and seek medical evaluation immediately. Do not restart nevirapine following severe skin rash, skin rash combined with increased transaminases or other symptoms, or hypersensitivity reaction.
The first 18 weeks of therapy with VIRAMUNE XR are a critical period during which intensive clinical and laboratory monitoring of patients is required to detect potentially life-threatening skin reactions. The optimal frequency of monitoring during this time period has not been established. Some experts recommend clinical and laboratory monitoring more often than once per month, and in particular, include monitoring of liver enzyme tests at baseline, prior to dose escalation and at two weeks post-dose escalation. After the initial 18-week period, frequent clinical and laboratory monitoring should continue throughout VIRAMUNE XR treatment. In addition, the 14-day lead-in period with VIRAMUNE 200 mg daily dosing has been demonstrated to reduce the frequency of rash [see DOSAGE AND ADMINISTRATION].
If patients present with a suspected nevirapine-associated rash, measure transaminases immediately. Permanently discontinue nevirapine in patients with rash-associated transaminase elevations [see Hepatotoxicity And Hepatic Impairment].
Patients must initiate therapy with immediate-release VIRAMUNE daily for the first 14 days. This lead-in period has been shown to reduce the frequency of rash. Discontinue nevirapine if a patient experiences severe rash or any rash accompanied by constitutional findings. Do not initiate VIRAMUNE XR if a patient experiencing a mild to moderate rash without constitutional symptoms during the 14-day immediate-release VIRAMUNE lead-in period of 200 mg/day (150 mg/m2/day in pediatric patients) until the rash has resolved. The total duration of the immediate-release VIRAMUNE lead-in dosing period must not exceed 28 days at which point an alternative regimen should be sought [see DOSAGE AND ADMINISTRATION]. Patients must be monitored closely if isolated rash of any severity occurs. Delay in stopping nevirapine treatment after the onset of rash may result in a more serious reaction.
Women appear to be at higher risk than men of developing rash with nevirapine.
In a clinical trial of immediate-release VIRAMUNE, concomitant prednisone use (40 mg per day for the first 14 days of nevirapine administration) was associated with an increase in incidence and severity of rash during the first 6 weeks of nevirapine therapy. Therefore, use of prednisone to prevent nevirapine-associated rash is not recommended.
VIRAMUNE XR must not be used as a single agent to treat HIV-1 or added on as a sole agent to a failing regimen. Resistant virus emerges rapidly when nevirapine is administered as monotherapy. The choice of new antiretroviral agents to be used in combination with nevirapine should take into consideration the potential for cross resistance. When discontinuing an antiretroviral regimen containing VIRAMUNE XR, the long half-life of nevirapine should be taken into account; if antiretrovirals with shorter half-lives than nevirapine are stopped concurrently, low plasma concentrations of nevirapine alone may persist for a week or longer and virus resistance may subsequently develop [see Microbiology].
See Table 4 for listings of established and potential drug interactions [see DRUG INTERACTIONS].
Concomitant use of St. John's wort (Hypericum perforatum) or St. John's wort-containing products and nevirapine is not recommended. Co-administration of St. John’s wort with non-nucleoside reverse transcriptase inhibitors (NNRTIs), including nevirapine, is expected to substantially decrease NNRTI concentrations and may result in sub-optimal levels of nevirapine and lead to loss of virologic response and possible resistance to nevirapine or to the class of NNRTIs.
Co-administration of nevirapine and efavirenz is not recommended as this combination has been associated with an increase in adverse reactions and no improvement in efficacy.
Immune Reconstitution Syndrome
Immune reconstitution syndrome has been reported in patients treated with combination antiretroviral therapy, including nevirapine. During the initial phase of combination antiretroviral treatment, patients whose immune system responds may develop an inflammatory response to indolent or residual opportunistic infections (such as Mycobacterium avium infection, cytomegalovirus, Pneumocystis jiroveci pneumonia, or tuberculosis), 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.
Redistribution/accumulation of body fat including central obesity, dorsocervical fat enlargement (buffalo hump), peripheral wasting, facial wasting, breast enlargement, and “cushingoid appearance” have been observed in patients receiving antiretroviral therapy. The mechanism and long-term consequences of these events are currently unknown. A causal relationship has not been established.
Patient Counseling Information
Advise the patient to read the FDA-approved patient labeling (Medication Guide).
Hepatotoxicity And Skin Reactions
Inform patients of the possibility of severe liver disease or skin reactions associated with nevirapine that may result in death. Instruct patients developing signs or symptoms of liver disease or severe skin reactions to discontinue nevirapine and seek medical attention immediately, including performance of laboratory monitoring. Symptoms of liver disease include fatigue, malaise, anorexia, nausea, jaundice, acholic stools, liver tenderness or hepatomegaly. Symptoms of severe skin or hypersensitivity reactions include rash accompanied by fever, general malaise, fatigue, muscle or joint aches, blisters, oral lesions, conjunctivitis, facial edema, and/or hepatitis.
Intensive clinical and laboratory monitoring, including liver enzymes, is essential during the first 18 weeks of therapy with nevirapine to detect potentially life-threatening hepatotoxicity and skin reactions. However, liver disease can occur after this period; therefore, monitoring should continue at frequent intervals throughout nevirapine treatment. Extra vigilance is warranted during the first 6 weeks of therapy, which is the period of greatest risk of hepatic events Advise patients with signs and symptoms of hepatitis to discontinue nevirapine and seek medical evaluation immediately. If nevirapine is discontinued due to hepatotoxicity, do not restart it. Patients, particularly women, with increased CD4+ cell count at initiation of nevirapine therapy (greater than 250 cells/mm3 in women and greater than 400 cells/mm3 in men) are at substantially higher risk for development of symptomatic hepatic events, often associated with rash. Advise patients that co-infection with hepatitis B or C
and/or increased transaminases at the start of therapy with nevirapine are associated with a greater risk of later symptomatic events (6 weeks or more after starting nevirapine) and asymptomatic increases in AST or ALT [see WARNINGS AND PRECAUTIONS].
The majority of rashes associated with nevirapine occur within the first 6 weeks of initiation of therapy. Instruct patients that if any rash occurs during the two-week lead-in period with immediate-release VIRAMUNE, do not initiate VIRAMUNE XR until the rash resolves. The total duration of the lead-in dosing period with immediate-release VIRAMUNE should not exceed 28 days, at which point an alternative regimen may need to be started. Any patient experiencing a rash should have their liver enzymes (AST, ALT) evaluated immediately. Patients with severe rash or hypersensitivity reactions should discontinue nevirapine immediately and consult a physician. Nevirapine should not be restarted following severe skin rash or hypersensitivity reaction. Women tend to be at higher risk for development of nevirapineassociated rash. For patients who interrupt VIRAMUNE XR dosing for more than 7 days and for whom restarting nevirapine therapy is not contraindicated, restart the recommended lead-in dosing with immediate-release VIRAMUNE using one 200 mg tablet daily (150 mg/m2/day in pediatric patients) for the first 14 days [see WARNINGS AND PRECAUTIONS].
Administration And Missed Dosage
Inform patients to take VIRAMUNE XR every day as prescribed. Advise patients not to alter the dose without consulting their doctor. If a dose is missed, patients should take the next dose as soon as possible. However, if a dose is skipped, the patient should not double the next dose.
Inform patients that they may occasionally see soft remnants of VIRAMUNE XR in their stool, which sometimes resemble intact tablets. These occurrences have not been shown to affect drug levels or response.
Instruct patients to swallow VIRAMUNE XR tablets whole. They must not be chewed, crushed, or divided.
To avoid overdose, inform patients that they should never take immediate-release VIRAMUNE and extended-release VIRAMUNE XR concomitantly.
VIRAMUNE XR may interact with some drugs; therefore, advise patients to report to their doctor the use of any other prescription, non-prescription medication or herbal products, particularly St. John's wort [see WARNINGS AND PRECAUTIONS and DRUG INTERACTIONS].
Immune Reconstitution Syndrome
Advise patients to inform their healthcare provider immediately of any signs or symptoms of infection, as inflammation from previous infection may occur soon after combination antiretroviral therapy, including when VIRAMUNE XR is started [see WARNINGS AND PRECAUTIONS].
Inform patients that redistribution or accumulation of body fat may occur in patients receiving antiretroviral therapy and that the cause and long-term health effects of these conditions are not known at this time [see WARNINGS AND PRECAUTIONS].
Advise patients that there is a pregnancy registry that monitors pregnancy outcomes in women exposed to VIRAMUNE XR during pregnancy [see Use In Specific Populations].
Instruct women with HIV-1 infection not to breastfeed because HIV-1 can be passed to the baby in the breast milk [see Use In Specific Populations].
Advise females of reproductive potential of the potential for impaired fertility from VIRAMUNE XR [see Use In Specific Populations and Nonclinical Toxicology]
Carcinogenesis, Mutagenesis, Impairment Of Fertility
Long-term carcinogenicity studies in mice and rats were carried out with nevirapine. Mice were dosed with 0, 50, 375 or 750 mg/kg/day for two years. Hepatocellular adenomas and carcinomas were increased at all doses in males and at the two high doses in females. In studies in which rats were administered nevirapine at doses of 0, 3.5, 17.5 or 35 mg/kg/day for two years, an increase in hepatocellular adenomas was seen in males at all doses and in females at the high dose. The systemic exposure (based on AUCs) at all doses in the two animal studies was lower than that measured in humans at the 200 mg twice daily dose of immediate-release VIRAMUNE. The mechanism of the carcinogenic potential is unknown.
However, in genetic toxicology assays, nevirapine showed no evidence of mutagenic or clastogenic activity in a battery of in vitro and in vivo studies. These included microbial assays for gene mutation (Ames: Salmonella strains and E. coli), mammalian cell gene mutation assay (CHO/HGPRT), cytogenetic assays using a Chinese hamster ovary cell line and a mouse bone marrow micronucleus assay following oral administration. Given the lack of genotoxic activity of nevirapine, the relevance to humans of hepatocellular neoplasms in nevirapine-treated mice and rats is not known.
Impairment Of Fertility
In reproductive toxicology studies, evidence of impaired fertility was seen in female rats at doses providing systemic exposure, based on AUC, approximately equivalent to that provided with the recommended clinical dose.
Use In Specific Populations
Pregnancy Exposure Registry
There is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to nevirapine during pregnancy. Healthcare providers are encouraged to register patients by calling the Antiretroviral Pregnancy Registry (APR) at 1-800-258-4263.
Available data for nevirapine in pregnant women is from the use of VIRAMUNE immediate-release. Available data from the APR show no difference in the risk of overall major birth defects for nevirapine compared with the background rate for major birth defects of 2.7% in a U.S. reference population of the Metropolitan Atlanta Congenital Defects Program (MACDP) [see Data]. The rate of miscarriage is not reported in the APR. The estimated background rate of miscarriage in clinically recognized pregnancies in the U.S. general population is 15-20%. The background risk of birth defects and miscarriage for the indicated population is unknown. Methodological limitations of the APR include the use of MACDP as the external comparator group. The MACDP population is not disease-specific, evaluates women and infants from a limited geographic area, and does not include outcomes for births that occurred at <20 weeks gestation.
There is a risk for severe hepatic events in pregnant women exposed to VIRAMUNE XR [see Clinical Considerations]. In animal reproduction studies, no evidence of adverse developmental outcomes were observed following oral administration of nevirapine during organogenesis in the rat and rabbit, at systemic exposures (AUC) to nevirapine approximately equal (rats) and 50% higher (rabbits) than the exposure in humans at the recommended 400mg daily dose [see Data].
Maternal Adverse Reactions
Severe hepatic events, including fatalities, have been reported in pregnant women receiving chronic nevirapine therapy as part of combination treatment of HIV-1
infection. Regardless of pregnancy status, women with CD4+ cell counts greater than 250 cells/mm3 should not initiate nevirapine unless the benefit outweighs the risk.
It is unclear if pregnancy augments the risk observed in non-pregnant women [see WARNINGS AND PRECAUTIONS].
Based on prospective reports to the APR of over 2600 exposures to nevirapine during pregnancy resulting in live births (including over 1100 exposed in the first trimester), there was no difference between nevirapine and overall birth defects compared with the background birth defect rate of 2.7% in a U.S. reference population of the MACDP. The prevalence of birth defects in live births was 2.8% (95% CI: 1.9%, 4.0%) following first trimester exposure to nevirapine- containing regimens and 3.2% (95% CI: 2.4%, 4.3%) with second/third-trimester exposure to nevirapine-containing regimens.
Nevirapine was administered orally to pregnant rats (at 0, 12.5, 25, and 50 mg/kg/day), and rabbits (at 0, 30, 100, and 300 mg/kg/day through organogenesis (on gestation days 7 through 16 and 6 through 18, respectively). No adverse developmental effects were observed at doses producing systemic exposures (AUC) approximately equivalent to (rats) or approximately 50% higher (rabbits) than human exposure at the recommended daily dose. In rats, decreased fetal body weights were observed at a maternally toxic dose at an exposure approximately 50% higher than the recommended daily dose.
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. Published data report that nevirapine immediate-release is present in human milk. There are limited data on the effects of nevirapine on the breastfed infant. There is no information on the effects of nevirapine on milk production. Because of the potential for (1) HIV-1 transmission (in HIV-negative infants), (2) developing viral resistance (in HIV-positive infants), and (3) serious adverse reactions in nursing infants, mothers should not breastfeed if they are receiving VIRAMUNE XR.
Females And Males Of Reproductive Potential
Limited human data are insufficient to determine the risk of infertility in humans. Based on results from animal fertility studies conducted in rats, VIRAMUME may reduce fertility in females of reproductive potential. It is not known if these effects on fertility are reversible [see Nonclinical Toxicology].
VIRAMUNE XR is indicated for use in combination with other antiretroviral agents for the treatment of HIV-1 infection in children 6 to less than 18 years of age [see INDICATIONS AND USAGE, DOSAGE AND ADMINISTRATION].
The use of VIRAMUNE XR for the treatment of HIV-1 infection in pediatric patients 6 to less than 18 years of age is based on pharmacokinetic, safety, and antiviral activity data from an open-label trial with VIRAMUNE XR. The results of this trial were supported by previous demonstration of efficacy in adult patients [see ADVERSE REACTIONS, CLINICAL PHARMACOLOGY, and Clinical Studies].
VIRAMUNE XR is not recommended for children less than 6 years of age. Trial 1100.1518 did not provide sufficient pharmacokinetic data for children 3 to less than 6 years of age to support the use of VIRAMUNE XR in this age group. Furthermore, VIRAMUNE XR is not recommended for children less than 3 years of age because they are not able to swallow tablets.
Clinical studies of VIRAMUNE XR did not include sufficient numbers of subjects aged 65 and older to determine whether elderly subjects respond differently from younger subjects. In general, dose selection for an elderly patient should be cautious, reflecting the greater frequency of decreased hepatic, renal or cardiac function, and of concomitant disease or other drug therapy.
In subjects with renal impairment (mild, moderate or severe), there were no significant changes in the pharmacokinetics of nevirapine. Nevirapine is extensively metabolized by the liver and nevirapine metabolites are extensively eliminated by the kidney. Nevirapine metabolites may accumulate in patients receiving dialysis; however, the clinical significance of this accumulation is not known. No adjustment in nevirapine dosing is required in patients with CrCL greater than or equal to 20 mL per min. The pharmacokinetics of nevirapine have not been evaluated in patients with CrCl less than 20 mL per min. In patients undergoing chronic hemodialysis, an additional dose of immediate-release VIRAMUNE (200 mg) following each dialysis treatment is indicated [see DOSAGE AND ADMINISTRATION and CLINICAL PHARMACOLOGY]. VIRAMUNE XR has not been studied in patients with renal dysfunction.
Because increased nevirapine levels and nevirapine accumulation may be observed in patients with serious liver disease, do not administer nevirapine to patients with moderate or severe (Child-Pugh Class B or C, respectively) hepatic impairment [see CONTRAINDICATIONS, WARNINGS AND PRECAUTIONS, and CLINICAL PHARMACOLOGY]. VIRAMUNE XR has not been evaluated in subjects with hepatic impairment.