Nevirapine Tablet, Extended Release
FDA Label NDC 0378-4890

HEPATOTOXICITY: Severe, life-threatening, and in some cases fatal hepatotoxicity, particularly in the first 18 weeks, has been reported in patients treated with nevirapine. In some cases, patients presented with non-specific prodromal signs or symptoms of hepatitis and progressed to hepatic failure. These events are often associated with rash. Female gender and higher CD4⁺ cell counts at initiation of therapy place patients at increased risk; women with CD4⁺ cell counts greater than 250 cells/mm³, including pregnant women receiving nevirapine in combination with other antiretrovirals for the treatment of HIV-1 infection, are at the greatest risk. However, hepatotoxicity associated with nevirapine use can occur in both genders, all CD4⁺ cell counts and at any time during treatment. Hepatic failure has also been reported in patients without HIV taking nevirapine for post-exposure prophylaxis (PEP). Use of nevirapine for occupational and non-occupational PEP is contraindicated [see Contraindications (4)]. Patients with signs or symptoms of hepatitis, or with increased transaminases combined with rash or other systemic symptoms, must discontinue nevirapine and seek medical evaluation immediately [see Warnings and Precautions (5.1)].

SKIN REACTIONS: Severe, life-threatening skin reactions, including fatal cases, have occurred in patients treated with nevirapine. These have included cases of Stevens-Johnson syndrome, toxic epidermal necrolysis, and hypersensitivity reactions characterized by rash, constitutional findings, and organ dysfunction. Patients developing signs or symptoms of severe skin reactions or hypersensitivity reactions must discontinue nevirapine and seek medical evaluation immediately. Transaminase levels should be checked immediately for all patients who develop a rash in the first 18 weeks of treatment. The 14-day lead-in period with immediate-release nevirapine 200 mg daily dosing has been observed to decrease the incidence of rash and must be followed [see Warnings and Precautions (5.2)].

MONITORING FOR HEPATOTOXICITY AND SKIN REACTIONS: Patients must be monitored intensively during the first 18 weeks of therapy with nevirapine to detect potentially life-threatening hepatotoxicity or skin reactions. Extra vigilance is warranted during the first 6 weeks of therapy, which is the period of greatest risk of these events. Do not restart nevirapine following clinical hepatitis, or transaminase elevations combined with rash or other systemic symptoms, or following severe skin rash or hypersensitivity reactions. In some cases, hepatic injury has progressed despite discontinuation of treatment.

Nevirapine extended-release tablets are indicated in combination with other antiretroviral agents for the treatment of human immunodeficiency virus (HIV-1) infection in adults and pediatric patients 6 to less than 18 years of age [see Clinical Studies (14.1, 14.2)].

Limitations of Use:

Based on serious and life-threatening hepatotoxicity observed in controlled and uncontrolled trials, nevirapine extended-release tablets are not recommended to be initiated, unless the benefit outweighs the risk, in:

• adult females with CD4⁺ cell counts greater than 250 cells/mm³ or
• adult males with CD4⁺ cell counts greater than 400 cells/mm³ [see Warnings and Precautions (5.1)].

• Nevirapine extended-release tablets must be swallowed whole and must not be chewed, crushed, or divided.
• Children should be assessed for their ability to swallow tablets before prescribing nevirapine extended-release tablets.
• Nevirapine extended-release tablets can be taken with or without food.
• No recommendations can be made regarding substitution of four nevirapine extended-release 100 mg tablets for one nevirapine extended-release 400 mg tablet.

• Patients must initiate therapy with one 200 mg tablet of immediate-release nevirapine daily for the first 14 days in combination with other antiretroviral agents. The 14-day lead-in period with nevirapine 200 mg daily dosing must be strictly followed (the lead-in period has been observed to decrease the incidence of rash), followed by one 400 mg tablet of nevirapine extended-release once daily [see Dosage and Administration (2.5), Warnings and Precautions (5.2)]. If rash persists beyond the 14-day lead-in period, with immediate-release nevirapine, do not begin dosing with nevirapine extended-release tablets. The lead-in dosing with 200 mg once daily immediate-release nevirapine should not be continued beyond 28 days, at which point an alternative regimen should be sought.

Patients already on a regimen of immediate-release nevirapine twice daily in combination with other antiretroviral agents can be switched to nevirapine extended-release tablets 400 mg once daily in combination with other antiretroviral agents without the 14-day lead-in period of immediate-release nevirapine. Patients already on a regimen of immediate-release nevirapine twice daily who switch to nevirapine extended-release tablet therapy should continue with their ongoing clinical and laboratory monitoring.

Pediatric patients may be dosed using nevirapine extended-release 400 mg or 100 mg tablets. Nevirapine extended-release tablets are dosed based on a patient’s body surface area (BSA) calculated using the Mosteller formula. All pediatric patients must initiate therapy with immediate-release nevirapine (as 150 mg/m² of nevirapine oral suspension or as nevirapine tablets), at a dose not to exceed 200 mg per day, administered once daily for the first 14 days. This lead-in period should be used because it has been demonstrated to reduce the frequency of rash. This lead-in period is not required if the patient is already on a regimen of twice daily immediate-release formulation in combination with other antiretroviral agents.

The recommended oral doses of nevirapine extended-release tablets for pediatric patients 6 to less than 18 years of age based upon their BSA are described in the table below. The total daily dose should not exceed 400 mg for any patient.

Mosteller Formula (Image 02)

Intensive clinical and laboratory monitoring, including liver enzyme tests, is essential at baseline and during the first 18 weeks of treatment with nevirapine. The optimal frequency of monitoring during this period has not been established. Some experts recommend clinical and laboratory monitoring more often than once per month, and in particular, would include monitoring of liver enzyme tests prior to beginning the 14-day lead-in period with immediate-release nevirapine, prior to initiation of nevirapine extended-release tablets, and at 2 weeks after initiation of nevirapine extended-release tablet therapy. After the initial 18-week period, frequent clinical and laboratory monitoring should continue throughout nevirapine extended-release tablet treatment [see Warnings and Precautions (5)]. In some cases, hepatic injury has progressed despite discontinuation of treatment.

Patients already on a regimen of immediate-release nevirapine twice daily who switch to nevirapine extended-release tablets once daily should continue with their ongoing clinical and laboratory monitoring.

Discontinue nevirapine if a patient experiences severe rash or any rash accompanied by constitutional findings [see Warnings and Precautions (5.2)]. Do not initiate therapy with nevirapine extended-release tablets if a patient experiences mild to moderate rash without constitutional symptoms during the 14-day lead-in period of immediate-release nevirapine until the rash has resolved [see Warnings and Precautions (5.2)]. The total duration of the once daily lead-in dosing period should not exceed 28 days at which point an alternative regimen should be sought.

If a clinical (symptomatic) hepatic event occurs, permanently discontinue nevirapine. Do not restart nevirapine after recovery [see Warnings and Precautions (5.1)].

For patients who interrupt nevirapine extended-release tablet dosing for more than 7 days, restart the recommended lead-in dosing with immediate-release nevirapine, using one 200 mg tablet daily for the first 14 days.

Patients with CrCL greater than or equal to 20 mL per min and not requiring dialysis do not require an adjustment in dosing. The pharmacokinetics of nevirapine have not been evaluated in patients with CrCL less than 20 mL per min. An additional 200 mg dose of immediate-release nevirapine following each dialysis treatment is indicated in patients requiring dialysis. Nevirapine metabolites may accumulate in patients receiving dialysis; however, the clinical significance of this accumulation is not known [see Clinical Pharmacology (12.3)]. Nevirapine extended-release tablets have not been studied in patients with renal dysfunction.

Nevirapine Extended-Release Tablets, USP are available containing 100 mg or 400 mg of nevirapine, USP.

• The 100 mg tablets are white to off-white, round, unscored tablets debossed with M on one side of the tablet and N100 on the other side.
• The 400 mg tablets are white to off-white, oval, unscored tablets debossed with M on one side of the tablet and N400 on the other side.

Nevirapine extended-release tablets are contraindicated:

• in patients with moderate or severe (Child-Pugh Class B or C, respectively) hepatic impairment [see Warnings and Precautions (5.1) and Use in Specific Populations (8.7)].
• for use as part of occupational and non-occupational post-exposure prophylaxis (PEP) regimens [see Warnings and Precautions (5.1)].

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 non-specific, 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 nevirapine extended-release tablets 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 2 weeks post-dose escalation. After the initial 18-week period, frequent clinical and laboratory monitoring should continue throughout nevirapine extended-release tablet 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 (2.4)].

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 nevirapine, 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 nevirapine in the setting of post-exposure prophylaxis (PEP), an unapproved use. Use of nevirapine extended-release tablets for occupational and non-occupational PEP is contraindicated [see Contraindications (4)].

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 (4), Use in Specific Populations (8.7), and Clinical Pharmacology (12.3)]. Nevirapine extended-release tablets have 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 nevirapine extended-release tablets 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 2 weeks post-dose escalation. After the initial 18-week period, frequent clinical and laboratory monitoring should continue throughout nevirapine extended-release tablet treatment. In addition, the 14-day lead-in period with nevirapine 200 mg daily dosing has been demonstrated to reduce the frequency of rash [see Dosage and Administration (2.1)].

If patients present with a suspected nevirapine-associated rash, measure transaminases immediately. Permanently discontinue nevirapine in patients with rash-associated transaminase elevations [see Warnings and Precautions (5.1)].

Patients must initiate therapy with immediate-release nevirapine 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 nevirapine extended-release tablets if a patient experiencing a mild to moderate rash without constitutional symptoms during the 14-day immediate-release nevirapine 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 nevirapine lead-in dosing period must not exceed 28 days at which point an alternative regimen should be sought [see Dosage and Administration (2.5)]. 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 nevirapine, 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.

Nevirapine extended-release tablets 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 nevirapine extended-release tablets, 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 (12.4)].

See Table 4 for listings of established and potential drug interactions [see Drug Interactions (7)].

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 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.

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 clinical practice.

The most serious adverse reactions associated with nevirapine are hepatitis, hepatic failure, Stevens-Johnson syndrome, toxic epidermal necrolysis, and hypersensitivity reactions. Hepatitis/hepatic failure may be isolated or associated with signs of hypersensitivity which may 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 [see Boxed Warning and Warnings and Precautions (5.1, 5.2)].

The most common clinical toxicity of nevirapine is rash, which can be severe or life-threatening [see Boxed Warning and Warnings and Precautions (5.2)]. Rash occurs most frequently within the first 6 weeks of therapy. Rashes are usually mild to moderate, maculopapular erythematous cutaneous eruptions, with or without pruritus, located on the trunk, face and extremities.

The safety database in nevirapine extended-release tablet clinical trials contains data from 800 subjects treated with nevirapine extended-release tablets and 654 subjects treated with immediate-release nevirapine.

In Trial 1100.1486 (VERxVE) treatment-naïve subjects received a lead-in dose of immediate-release nevirapine 200 mg once daily for 14 days (n = 1068) and then were randomized to receive either immediate-release nevirapine 200 mg twice daily (n = 506) or nevirapine extended-release tablets 400 mg once daily (n = 505). All subjects received tenofovir + emtricitabine as background therapy. Subjects were enrolled with CD4⁺ counts less than 250 cells/mm³ for women and less than 400 cells/mm³ for men [see Indications and Usage (1)]. Data on potential symptoms of hepatic events were prospectively collected in this trial. The safety data include all subject visits up to the time of the last subject’s completion of the 96 week endpoint in the trial (mean observation period 98 weeks).

After the lead-in period, the incidence of any hepatic event was 9% in the immediate-release nevirapine group and 6% in the nevirapine extended-release tablet group; the incidence of symptomatic hepatic events (anorexia, jaundice, vomiting) was 3% and 2%, respectively. The incidence of GRADE 3 or 4 ALT/AST elevation was 8% in both the immediate-release nevirapine group and nevirapine extended-release tablet group. Overall, there was a comparable incidence of symptomatic hepatic events among men and women enrolled in VERxVE.

Severe or life-threatening rash considered to be related to nevirapine treatment occurred in 1% of subjects during the lead-in phase with immediate-release nevirapine, and in 1% of subjects in either treatment group during the randomization phase. In addition, six cases of Stevens-Johnson syndrome were reported in the trial; all but one occurred within the first 30 days of nevirapine treatment.

No Grade 2 or above adverse reactions judged to be related to treatment by the investigator occurred in more than 2% of subjects during the 14-day lead-in with immediate-release nevirapine (200 mg once daily), with the exception of rash which occurred in 4% of subjects.

Adverse reactions of at least moderate intensity (Grades 2 or above) 2% or more of treatment-naïve subjects receiving either immediate-release nevirapine or nevirapine extended-release tablets after randomization in Trial 1100.1486 are shown in Table 2.

Liver enzyme test abnormalities (AST, ALT) were observed in subjects receiving nevirapine extended-release tablets. Asymptomatic elevations in GGT occur frequently but are not a contraindication to continue therapy with nevirapine in the absence of elevations in other liver enzyme tests. Laboratory abnormalities that occurred in trial 1100.1486 are shown in Table 3.

In Trial 1100.1526 (TRANxITION) subjects on immediate-release nevirapine 200 mg twice daily for at least 18 weeks were randomized to either receive nevirapine extended-release tablets 400 mg once daily (n = 295) or remain on their immediate-release nevirapine treatment (n = 148). Adverse reactions observed for nevirapine extended-release tablet subjects (48 week analysis) were similar to those observed in trial 1100.1486, as displayed in Table 2.

Adverse reactions were assessed in Trial 1100.1518, an open-label, multiple-dose, non-randomized, crossover trial to evaluate the safety and steady-state pharmacokinetic parameters of nevirapine extended-release tablets in HIV-1-infected pediatric subjects 3 to less than 18 years of age. Safety was further examined in an optional extension phase of the trial. Forty subjects who completed the pharmacokinetic part of the trial were treated with nevirapine extended-release tablets once daily in combination with other antiretrovirals for a median duration of 33 weeks. The most frequently reported adverse reactions related to nevirapine extended-release tablets in pediatric subjects were similar to those observed in adults. In pediatric subjects the incidence of Grade 2 or higher drug-related rash was 1%. There were no adverse reactions of Grade 2 or above which were considered to be related to treatment by the investigator that occurred in more than 1% of subjects [see Use in Specific Populations (8.4), Clinical Pharmacology (12.3), and Clinical Studies (14.2)].

The following adverse reactions have been identified during post-approval use of immediate-release nevirapine. 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.

Body as a Whole: fever, somnolence, drug withdrawal [see Drug Interactions (7)], redistribution/accumulation of body fat [see Warnings and Precautions (5.6)]

Gastrointestinal: vomiting

Liver and Biliary: jaundice, fulminant and cholestatic hepatitis, hepatic necrosis, hepatic failure

Hematology: anemia, eosinophilia, neutropenia

Investigations: decreased serum phosphorus

Musculoskeletal: arthralgia, rhabdomyolysis associated with skin and/or liver reactions

Neurologic: paraesthesia

Skin and Appendages: allergic reactions including anaphylaxis, angioedema, bullous eruptions, ulcerative stomatitis and urticaria have all been reported. In addition, hypersensitivity syndrome and hypersensitivity reactions with rash associated with constitutional findings such as fever, blistering, oral lesions, conjunctivitis, facial edema, muscle or joint aches, general malaise, fatigue, or significant hepatic abnormalities [see Warnings and Precautions (5.1)] plus one or more of the following: hepatitis, eosinophilia, granulocytopenia, lymphadenopathy, and/or renal dysfunction have been reported.

Nevirapine is principally metabolized by the liver via the cytochrome P450 isoenzymes, 3A and 2B6. Nevirapine is known to be an inducer of these enzymes. As a result, drugs that are metabolized by these enzyme systems may have lower than expected plasma levels when co-administered with nevirapine.

The results of drug interactions studies with immediate-release nevirapine are expected to also apply to nevirapine extended-release tablets. The specific pharmacokinetic changes that occur with co-administration of nevirapine and other drugs are listed in Clinical Pharmacology, Table 5. Clinical comments about possible dosage modifications based on established drug interactions are listed in Table 4. The data in Tables 4 and 5 are based on the results of drug interaction studies conducted in HIV-1 seropositive subjects unless otherwise indicated. In addition to established drug interactions, there may be potential pharmacokinetic interactions between nevirapine and other drug classes that are metabolized by the cytochrome P450 system. These potential drug interactions are also listed in Table 4. Although specific drug interaction studies in HIV-1 seropositive subjects have not been conducted for some classes of drugs listed in Table 4, additional clinical monitoring may be warranted when co-administering these drugs.

The in vitro interaction between nevirapine and the antithrombotic agent warfarin is complex. As a result, when giving these drugs concomitantly, plasma warfarin levels may change with the potential for increases in coagulation time. When warfarin is co-administered with nevirapine, anticoagulation levels should be monitored frequently.

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 nevirapine 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 nevirapine extended-release tablets [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 400 mg daily dose [see Data].

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 (5.1)].

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 nevirapine extended-release tablets.

Limited human data are insufficient to determine the risk of infertility in humans. Based on results from animal fertility studies conducted in rats, nevirapine extended-release tablets may reduce fertility in females of reproductive potential. It is not known if these effects on fertility are reversible [see Nonclinical Toxicology (13.1)].

Nevirapine extended-release tablets are 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 (1), Dosage and Administration (2.3)].

The use of nevirapine extended-release tablets 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 nevirapine extended-release tablets. The results of this trial were supported by previous demonstration of efficacy in adult patients [see Adverse Reactions (6.1), Clinical Pharmacology (12.3), and Clinical Studies (14.2)].

Nevirapine extended-release tablets are 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 nevirapine extended-release tablets in this age group. Furthermore, nevirapine extended-release tablets are not recommended for children less than 3 years of age because they are not able to swallow tablets.

Clinical studies of nevirapine extended-release tablets 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 nevirapine (200 mg) following each dialysis treatment is indicated [see Dosage and Administration (2.5) and Clinical Pharmacology (12.3)]. Nevirapine extended-release tablets have 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 (4), Warnings and Precautions (5.1), and Clinical Pharmacology (12.3)]. Nevirapine extended-release tablets have not been evaluated in subjects with hepatic impairment.

There is no known antidote for nevirapine overdosage. Cases of immediate-release nevirapine overdose at doses ranging from 800 to 1800 mg per day for up to 15 days have been reported. Patients have experienced events including edema, erythema nodosum, fatigue, fever, headache, insomnia, nausea, pulmonary infiltrates, rash, vertigo, vomiting and weight decrease. All events subsided following discontinuation of immediate-release nevirapine.

Nevirapine is a non-nucleoside reverse transcriptase inhibitor (NNRTI) with activity against Human Immunodeficiency Virus Type 1 (HIV-1). Nevirapine is structurally a member of the dipyridodiazepinone chemical class of compounds.

The chemical name of nevirapine is 11-Cyclopropyl-5,11-dihydro-4-methyl-6H-dipyrido[3,2-b:2’,3’-e][1, 4]diazepin-6-one. Nevirapine, USP is a white to off-white, odorless to nearly odorless crystalline powder with the molecular weight of 266.30 and the molecular formula C₁₅H₁₄N₄O. Nevirapine has the following structural formula:

Nevirapine Structural Formula (Image 03)

Nevirapine extended-release tablets, USP are for oral administration. Each tablet contains 100 mg or 400 mg of nevirapine and the inactive ingredients hypromellose, lactose monohydrate, and sodium stearyl fumarate.

Nevirapine is an antiretroviral drug [see Microbiology (12.4)].

The single-dose pharmacokinetics of nevirapine extended-release tablets was studied in 17 healthy volunteers. Nevirapine was absorbed with a median t_max of approximately 24 hrs. The mean C_max and AUC_0-∞ of nevirapine were 2060 ng per mL and 161,000 ng*hr/mL, respectively. The bioavailability of 400 mg of nevirapine extended-release tablets, relative to 400 mg of immediate-release nevirapine, was approximately 75%.

The multiple-dose pharmacokinetics of nevirapine extended-release tablets was studied in 24 HIV-1 infected subjects who switched from chronic immediate-release nevirapine to nevirapine extended-release tablets. The mean nevirapine AUC_0-24,ss and C_min,ss after 19 days of nevirapine extended-release tablet dosing under fasted conditions were 82,000 ng*hr/mL and 2920 ng per mL, respectively. When nevirapine extended-release tablets were administered under fed conditions, the mean nevirapine AUC_0-24,ss and C_min,ss were 96,700 ng*hr/mL and 3150 ng per mL, respectively. The bioavailability of 400 mg of nevirapine extended-release tablets, relative to 400 mg of immediate-release nevirapine, under fasted and fed conditions, was 80% and 94%, respectively. The difference in the bioavailability of nevirapine, when nevirapine extended-release tablets are dosed under fasted or fed conditions, is not considered clinically relevant. Nevirapine extended-release tablets can be taken with or without food.

In single-dose, parallel-group bioavailability trial (1100.1517) in adults, the nevirapine extended-release 100 mg tablet exhibited extended-release characteristics of prolonged absorption and lower maximal concentration, as compared to the immediate-release nevirapine 200 mg tablet.

Nevirapine is highly lipophilic and is essentially nonionized at physiologic pH. Following intravenous administration to healthy adults, the apparent volume of distribution (Vdss) of nevirapine was 1.21 ± 0.09 L/kg, suggesting that nevirapine is widely distributed in humans. Nevirapine readily crosses the placenta and is also found in breast milk [see Use in Specific Populations (8.2)]. Nevirapine is about 60% bound to plasma proteins in the plasma concentration range of 1-10 mcg per mL. Nevirapine concentrations in human cerebrospinal fluid (n = 6) were 45% (± 5%) of the concentrations in plasma; this ratio is approximately equal to the fraction not bound to plasma protein.

In vivo studies in humans and in vitro studies with human liver microsomes have shown that nevirapine is extensively biotransformed via cytochrome P450 (oxidative) metabolism to several hydroxylated metabolites. In vitro studies with human liver microsomes suggest that oxidative metabolism of nevirapine is mediated primarily by cytochrome P450 (CYP) isozymes from the CYP3A and CYP2B6 families, although other isozymes may have a secondary role. In a mass balance/excretion trial in eight healthy male volunteers dosed to steady-state with immediate-release nevirapine 200 mg given twice daily followed by a single 50 mg dose of ¹⁴C-nevirapine, approximately 91.4 ± 10.5% of the radiolabeled dose was recovered, with urine (81.3 ± 11.1%) representing the primary route of excretion compared to feces (10.1 ± 1.5%). Greater than 80% of the radioactivity in urine was made up of glucuronide conjugates of hydroxylated metabolites. Thus cytochrome P450 metabolism, glucuronide conjugation, and urinary excretion of glucuronidated metabolites represent the primary route of nevirapine biotransformation and elimination in humans. Only a small fraction (less than 5%) of the radioactivity in urine (representing less than 3% of the total dose) was made up of parent compound; therefore, renal excretion plays a minor role in elimination of the parent compound.

Nevirapine is an inducer of hepatic cytochrome P450 (CYP) metabolic enzymes 3A and 2B6. Nevirapine induces CYP3A and CYP2B6 by approximately 20-25%, as indicated by erythromycin breath test results and urine metabolites. Autoinduction of CYP3A and CYP2B6 mediated metabolism leads to an approximately 1.5- to 2-fold increase in the apparent oral clearance of nevirapine as treatment continues from a single dose to 2-4 weeks of dosing with 200-400 mg per day of immediate-release nevirapine. Autoinduction also results in a corresponding decrease in the terminal phase half-life of nevirapine in plasma, from approximately 45 hours (single dose) to approximately 25-30 hours following multiple dosing with 200-400 mg per day.

HIV-1 seronegative adults with mild (CrCL 50-79 mL per min; n = 7), moderate (CrCL 30-49 mL per min; n = 6), or severe (CrCL less than 30 mL per min; n = 4) renal impairment received a single 200 mg dose of immediate-release nevirapine in a pharmacokinetic trial. These subjects did not require dialysis. The trial included six additional subjects with renal failure requiring dialysis.

In subjects with renal impairment (mild, moderate or severe), there were no significant changes in the pharmacokinetics of nevirapine. However, subjects requiring dialysis exhibited a 44% reduction in nevirapine AUC over a 1-week exposure period. There was also evidence of accumulation of nevirapine hydroxy-metabolites in plasma in subjects requiring dialysis. An additional 200 mg dose of immediate-release nevirapine following each dialysis treatment is indicated [see Dosage and Administration (2.5) and Use in Specific Populations (8.6)]. Nevirapine extended-release tablets have not been studied in patients with renal dysfunction.

In a steady-state trial comparing 46 subjects with mild (n = 17; expansion of some portal areas; Ishak Score 1-2), moderate (n = 20; expansion of most portal areas with occasional portal-to-portal and portal-to-central bridging; Ishak Score 3-4), or severe (n = 9; marked bridging with occasional cirrhosis without decompensation indicating Child-Pugh A; Ishak Score 5-6) fibrosis as a measure of hepatic impairment, the multiple dose pharmacokinetic disposition of nevirapine and its five oxidative metabolites were not altered. However, approximately 15% of these subjects with hepatic fibrosis had nevirapine trough concentrations above 9,000 mcg per mL (2-fold the usual mean trough). Therefore, patients with hepatic impairment should be monitored carefully for evidence of drug-induced toxicity [see Warnings and Precautions (5.1)]. The subjects studied were receiving antiretroviral therapy containing immediate-release nevirapine 200 mg twice daily for at least 6 weeks prior to pharmacokinetic sampling, with a median duration of therapy of 3.4 years.

In a pharmacokinetic trial where HIV-1 negative cirrhotic subjects with mild (Child-Pugh A; n = 6) or moderate (Child-Pugh B; n = 4) hepatic impairment received a single 200 mg dose of immediate-release nevirapine, a significant increase in the AUC of nevirapine was observed in one subject with Child-Pugh B and ascites suggesting that patients with worsening hepatic function and ascites may be at risk of accumulating nevirapine in the systemic circulation. Because nevirapine induces its own metabolism with multiple dosing, this single-dose trial may not reflect the impact of hepatic impairment on multiple-dose pharmacokinetics.

Do not administer nevirapine to patients with moderate or severe (Child-Pugh Class B or C, respectively) hepatic impairment [see Contraindications (4), Warnings and Precautions (5.1), and Use in Specific Populations (8.7)]. Nevirapine extended-release tablets have not been evaluated in patients with hepatic impairment.

In the multinational 2NN trial of immediate-release nevirapine, a population pharmacokinetic substudy of 1077 subjects was performed that included 391 females. Female subjects showed a 13.8% lower clearance of nevirapine than did men. Since neither body weight nor Body Mass Index (BMI) had an influence on the clearance of nevirapine, the effect of gender cannot solely be explained by body size.

The effects of gender on the pharmacokinetics of nevirapine extended-release tablets have been investigated in Trial 1100.1486. Female subjects tend to have higher (approximately 20-30%) trough concentrations in both nevirapine extended-release tablets and immediate-release nevirapine treatment groups.

An evaluation of nevirapine plasma concentrations (pooled data from several clinical trials) from HIV-1-infected subjects (27 Black, 24 Hispanic, 189 Caucasian) revealed no marked difference in nevirapine steady-state trough concentrations (median C_min,ss = 4.7 mcg per mL Black, 3.8 mcg per mL Hispanic, 4.3 mcg per mL Caucasian) with long-term treatment with immediate-release nevirapine at 400 mg per day. However, the pharmacokinetics of nevirapine have not been evaluated specifically for the effects of ethnicity.

Black subjects (n = 80/group) in Trial 1100.1486 showed approximately 30-35% higher trough concentrations than Caucasian subjects (250-325 subjects/group) in both immediate-release nevirapine and nevirapine extended-release tablet treatment groups over 96 weeks of treatment at 400 mg per day.

Nevirapine pharmacokinetics in HIV-1-infected adults do not appear to change with age (range 18-68 years); however, nevirapine has not been extensively evaluated in patients beyond the age of 65 years [see Use in Specific Populations (8.5)].

The pharmacokinetics of nevirapine extended-release tablets were assessed in HIV-1 infected children 3 to less than 18 years of age. Children enrolled received weight or body surface area dose-adjusted immediate-release nevirapine in combination with other antiretrovirals for a minimum of 18 weeks and then were switched to nevirapine extended-release tablets in combination with other antiretrovirals for 10 days, after which steady-state pharmacokinetic parameters were determined.

Overall, the mean systemic nevirapine exposures in children 6 to less than 18 years of age following administration of nevirapine extended-release tablets and immediate-release nevirapine were similar. Based on intensive PK data (N = 17), the observed geometric mean ratios of nevirapine extended-release tablets to immediate-release nevirapine were approximately 97% for C_min,ss and 94% for AUC_ss with 90% confidence intervals within 80-125%; the ratio for C_max,ss was lower and consistent with a once daily extended-release dosage form.

Trial 1100.1518 did not provide sufficient pharmacokinetic data for children 3 to less than 6 years of age to support the use of nevirapine extended-release tablets in this age group.

[See Drug Interactions (7).]

Nevirapine induces hepatic cytochrome P450 metabolic isoenzymes 3A and 2B6. Co-administration of nevirapine extended-release tablets and drugs primarily metabolized by CYP3A or CYP2B6 may result in decreased plasma concentrations of these drugs and attenuate their therapeutic effects.

While primarily an inducer of cytochrome P450 3A and 2B6 enzymes, nevirapine may also inhibit this system. Among human hepatic cytochrome P450s, nevirapine was capable in vitro of inhibiting the 10-hydroxylation of (R)-warfarin (CYP3A). The estimated K_i for the inhibition of CYP3A was 270 micromolar, a concentration that is unlikely to be achieved in patients as the therapeutic range is less than 25 micromolar. Therefore, nevirapine may have minimal inhibitory effect on other substrates of CYP3A.

Nevirapine does not appear to affect the plasma concentrations of drugs that are substrates of other CYP450 enzyme systems, such as 1A2, 2D6, 2A6, 2E1, 2C9, or 2C19.

Table 5 (see below) contains the results of drug interaction trials performed with immediate-release nevirapine and other drugs likely to be co-administered. The effects of nevirapine on the AUC, C_max, and C_min of co-administered drugs are summarized. Results of drug interaction studies with immediate-release nevirapine are expected to also apply to nevirapine extended-release tablets.

Because of the design of the drug interaction trials (addition of 28 days of nevirapine therapy to existing HIV-1 therapy), the effect of the concomitant drug on plasma nevirapine steady-state concentrations was estimated by comparison to historical controls.

Administration of rifampin had a clinically significant effect on nevirapine pharmacokinetics, decreasing AUC and C_max by greater than 50%. Administration of fluconazole resulted in an approximate 100% increase in nevirapine exposure, based on a comparison to historic data [see Drug Interactions (7)]. The effect of other drugs listed in Table 5 on nevirapine pharmacokinetics was not significant. No significant interaction was observed when tipranavir was co-administered with low-dose ritonavir and nevirapine.

Nevirapine is a non-nucleoside reverse transcriptase inhibitor (NNRTI) of HIV-1. Nevirapine binds directly to reverse transcriptase (RT) and blocks the RNA-dependent and DNA-dependent DNA polymerase activities by causing a disruption of the enzyme’s catalytic site. The activity of nevirapine does not compete with template or nucleoside triphosphates. HIV-2 RT and eukaryotic DNA polymerases (such as human DNA polymerases α, ß, γ, or δ) are not inhibited by nevirapine.

The antiviral activity of nevirapine has been measured in a variety of cell lines including peripheral blood mononuclear cells, monocyte-derived macrophages, and lymphoblastoid cell lines. In an assay using human embryonic kidney 293 cells, the median EC₅₀ value (50% inhibitory concentration) of nevirapine was 90 nM against a panel of 2923 wild-type isolates of HIV-1 that were primarily (93%) clade B clinical isolates from the United States. The 99^th percentile EC₅₀ value was 470 nM in this trial. The median EC₅₀ value was 63 nM (range 14-302 nM, n = 29) against clinical isolates of HIV-1 clades A, B, C, D, F, G, and H, and circulating recombinant forms CRF01_AE, CRF02_AG and CRF12_BF. Nevirapine had no antiviral activity in cell culture against group O HIV-1 isolates (n = 3) or HIV-2 isolates (n = 3) replicating in cord blood mononuclear cells. Nevirapine in combination with efavirenz exhibited strong antagonistic anti-HIV-1 activity in cell culture and was additive to antagonistic with the protease inhibitor ritonavir or the fusion inhibitor enfuvirtide. The anti-HIV-1 activity of nevirapine was not antagonistic in combination with the NRTIs abacavir, didanosine, emtricitabine, lamivudine, stavudine, tenofovir and zidovudine, and the protease inhibitors amprenavir, atazanavir, indinavir, lopinavir, nelfinavir, saquinavir and tipranavir. The anti-HIV-1 activity of nevirapine was antagonized by the anti-HBV drug adefovir and by the anti-HCV drug ribavirin in cell culture.

HIV-1 isolates with reduced susceptibility (100- to 250-fold) to nevirapine emerge in cell culture. Genotypic analysis showed mutations in the HIV-1 RT gene encoding Y181C and/or V106A substitutions depending upon the virus strain and cell line employed. Time to emergence of nevirapine resistance in cell culture was not altered when selection included nevirapine in combination with several other NNRTIs.

Phenotypic and genotypic changes in HIV-1 isolates from treatment-naïve subjects receiving either nevirapine (n = 24) or nevirapine and zidovudine (n = 14) were monitored in Phase 1 and 2 trials ranging from 1 to 12 weeks or longer. After 1 week of nevirapine monotherapy, isolates from 3/3 subjects had decreased susceptibility to nevirapine in cell culture. One or more of the RT mutations resulting in amino acid substitutions K103N, V106A, V108I, Y181C, Y188C, and G190A were detected in HIV-1 isolates from some subjects as early as 2 weeks after therapy initiation. By week 8 of nevirapine monotherapy, 100% of the subjects tested (n = 24) had HIV-1 isolates with a greater than 100-fold decrease in susceptibility to nevirapine in cell culture compared to baseline, and had one or more of the nevirapine-associated RT resistance substitutions. Nineteen of these subjects (80%) had isolates with Y181C substitutions regardless of dose.

Genotypic analysis of isolates from antiretroviral-naïve subjects experiencing virologic failure (n = 71) receiving nevirapine once daily (n = 25) or twice daily (n = 46) in combination with lamivudine and stavudine (trial 2NN) for 48 weeks showed that isolates from 8/25 and 23/46 subjects, respectively, contained one or more of the following NNRTI resistance-associated substitutions: Y181C, K101E, G190A/S, K103N, V106A/M, V108I, Y188C/L, A98G, F227L, and M230L.

For trial 1100.1486, genotypic analysis was performed for baseline and on-therapy isolates from 23 and 34 subjects who experienced virologic failure in the nevirapine extended-release tablet and immediate-release nevirapine treatment group, respectively. Nevirapine resistance-associated substitutions developed in the on-therapy isolates of 78% (18/23) of the subjects who had virologic failures in the nevirapine extended-release tablet treatment group and 88% (30/34) of the subjects in the immediate-release nevirapine treatment group, respectively. The Y181C nevirapine resistance-associated substitution was found alone or in combination with other nevirapine resistance-associated substitutions (K101E, K103N, V106A, V108I, V179D/E/I, Y188 C/F/H/L/N, G190A, P225H, F227L, M230L) in isolates from 14 subjects failing nevirapine extended-release tablet treatment and 25 subjects failing immediate-release nevirapine treatment. On-therapy isolates from one subject in nevirapine extended-release tablet treatment group developed a novel amino acid substitution Y181I and isolates from another subject in the immediate-release nevirapine treatment group developed a novel amino acid substitution Y188N. Phenotypic analysis showed that Y188N and Y181I substitutions conferred 103- and 22-fold reductions in susceptibility to nevirapine, respectively.

Rapid emergence of HIV-1 strains which are cross-resistant to NNRTIs has been observed in cell culture. Nevirapine-resistant HIV-1 isolates were cross-resistant to the NNRTIs delavirdine, efavirenz, and etravirine. The Y188N conferred 22- and 7-fold reductions in susceptibility to delavirdine and efavirenz, respectively, but showed no decrease in susceptibility to etravirine. Similarly, the Y181I substitution reduced susceptibility to delavirdine and etravirine 3- and 8-fold, respectively, but did not reduce susceptibility to efavirenz. However, nevirapine-resistant isolates were susceptible to the NRTIs ddI and ZDV. Similarly, ZDV-resistant isolates were susceptible to nevirapine in cell culture.

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 2 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 2 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 nevirapine. 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.

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.

Animal studies have shown that nevirapine is widely distributed to nearly all tissues and readily crosses the blood-brain barrier.

The clinical efficacy of nevirapine extended-release tablets is based on 96-week data from an ongoing, randomized, double-blind, double-dummy, Phase 3 trial (Trial 1100.1486, VERxVE) in treatment-naïve subjects and on 48-week data in an ongoing, randomized, open-label trial in subjects who switched from immediate-release nevirapine tablets administered twice daily to nevirapine extended-release tablets administered once daily (Trial 1100.1526, TRANxITION).

Trial 1100.1486 (VERxVE) is a Phase 3 trial in which treatment-naïve subjects received immediate-release nevirapine 200 mg once daily for 14 days and then were randomized to receive either immediate-release nevirapine 200 mg twice daily or nevirapine extended-release tablets 400 mg once daily. All subjects received tenofovir + emtricitabine as background therapy. Randomization was stratified by screening HIV-1 RNA level (less than or equal to 100,000 copies per mL and greater than 100,000 copies per mL). Subject demographic and baseline disease characteristics were balanced between the two treatment groups. With respect to demographics: 85% of the subjects were male, 75% were white, 20% were black, and approximately 29% were from North America. With respect to baseline disease characteristics: mean viral load was 4.7 log₁₀ copies per mL, mean CD4⁺ cell count was 228 cells/mm³ and 73% of subjects had clade B HIV-1 subtype. Approximately two-thirds of the subjects had a baseline HIV-RNA level of less than or equal to 100,000 copies per mL.

Table 6 describes week 96 outcomes in the Trial 1100.1486 (VERxVE). These outcomes include all subjects who were randomized after the 14 day lead-in with immediate-release nevirapine and received at least one dose of blinded study medication.

At 96 weeks, mean change from baseline in CD4⁺ cell count adjusting for baseline HIV-1 viral load stratum was 222 cells/mm³ and 244 cells/mm³ for the groups receiving immediate-release nevirapine and nevirapine extended-release tablets, respectively.

Trial 1100.1526 (TRANxITION) is a Phase 3 trial to evaluate safety and antiviral activity of switching from immediate-release nevirapine to nevirapine extended-release tablets. In this open-label trial, 443 subjects already on an antiviral regimen containing immediate-release nevirapine 200 mg twice daily with HIV-1 RNA less than 50 copies per mL were randomized in a 2:1 ratio to nevirapine extended-release tablets 400 mg once daily or immediate-release nevirapine 200 mg twice daily. Approximately half of the subjects had tenofovir + emtricitabine as their background therapy, with the remaining subjects receiving abacavir sulfate + lamivudine or zidovudine + lamivudine. Approximately half of the subjects had at least 3 years of exposure to immediate-release nevirapine prior to entering the trial.

At 48 weeks after randomization in Trial 1100.1526, 91% of subjects receiving immediate-release nevirapine 200 mg twice daily and 93% of subjects receiving nevirapine extended-release tablets 400 mg once daily continued to have HIV-1 RNA less than 50 copies per mL.

Trial 1100.1518 was an open-label, multiple-dose, non-randomized, crossover trial performed in 85 HIV-1 infected pediatric subjects 3 to less than 18 years of age who had received at least 18 weeks of immediate-release nevirapine and had plasma HIV-1 RNA less than 50 copies per mL prior to trial enrollment. Subjects were stratified according to age (3 to less than 6 years, 6 to less than 12 years, and 12 to less than 18 years). Following a 10-day period with immediate-release nevirapine, subjects were treated with nevirapine extended-release tablets once daily in combination with other antiretrovirals for 10 days, after which steady-state pharmacokinetic parameters were determined. Forty of the 80 subjects who completed the initial part of the study were enrolled in an optional extension phase of the trial which evaluated the safety and antiviral activity of nevirapine extended-release tablets through a minimum of 24 weeks of treatment. Zidovudine or stavudine plus lamivudine were the most commonly used background therapies in subjects who entered the optional extension phase.

Baseline demographics included: 55% of the subjects were female, 93% were black, 7% were white, and approximately 84% were from Africa. Subjects had a median baseline CD4⁺ cell count of 925 cells/mm³ (range 207 to 2057 cells/mm³).

Of the 40 subjects who entered the treatment extension phase, 39 completed at least 24 weeks of treatment and one subject discontinued prematurely due to an adverse reaction. After 24 weeks or more of treatment with nevirapine extended-release tablets, all 39 subjects continued to have plasma HIV-1 RNA less than 50 copies per mL. Median CD4⁺ cell counts for the 3 to less than 6 year, 6 to less than 12 year, and 12 to less than 18 year age groups were 1113 cells/mm³, 853 cells/mm³, and 682 cells/mm³, respectively. These CD4⁺ cell counts were similar to those observed at baseline.

Nevirapine Extended-Release Tablets, USP are available containing 100 mg or 400 mg of nevirapine, USP.

The 100 mg tablets are white to off-white, round, unscored tablets debossed with M on one side of the tablet and N100 on the other side. They are available as follows:

NDC 0378-6950-77
bottles of 90 tablets

The 400 mg tablets are white to off-white, oval, unscored tablets debossed with M on one side of the tablet and N400 on the other side. They are available as follows:

NDC 0378-4890-93
bottles of 30 tablets

Store at 20° to 25°C (68° to 77°F). [See USP Controlled Room Temperature.]

Store in a safe place out of the reach of children.

Dispense in a tight, light-resistant container as defined in the USP using a child-resistant closure.

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 (5.1)].

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 2-week lead-in period with immediate-release nevirapine, do not initiate nevirapine extended-release tablets until the rash resolves. The total duration of the lead-in dosing period with immediate-release nevirapine 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 nevirapine-associated rash. For patients who interrupt nevirapine extended-release tablet dosing for more than 7 days and for whom restarting nevirapine therapy is not contraindicated, restart the recommended lead-in dosing with immediate-release nevirapine using one 200 mg tablet daily (150 mg/m²/day in pediatric patients) for the first 14 days [see Warnings and Precautions (5.2)].

Administration and Missed Dosage: Inform patients to take nevirapine extended-release tablets 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 nevirapine extended-release tablets in their stool, which sometimes resemble intact tablets. These occurrences have not been shown to affect drug levels or response.

Instruct patients to swallow nevirapine extended-release tablets whole. They must not be chewed, crushed, or divided.

To avoid overdose, inform patients that they should never take immediate-release nevirapine and extended-release nevirapine tablets concomitantly.

Drug Interactions: Nevirapine extended-release tablets 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 (5.4) and Drug Interactions (7)].

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 nevirapine extended-release tablets are started [see Warnings and Precautions (5.5)].

Fat Redistribution: 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 (5.6)].

Pregnancy Registry: Advise patients that there is a pregnancy registry that monitors pregnancy outcomes in women exposed to nevirapine extended-release tablets during pregnancy [see Use in Specific Populations (8.1)].

Lactation: 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 (8.2)].

Infertility: Advise females of reproductive potential of the potential for impaired fertility from nevirapine extended-release tablets [see Use in Specific Populations (8.3) and Nonclinical Toxicology (13.1)].

Starting nevirapine tablets:

• Call your doctor right away if you get a skin rash during the first 14 days of nevirapine treatment.
• Do not increase your dose to 2 times a day if you have a rash.
• You should never take your starting dose for longer than 28 days. If after 28 days you are still receiving this starting dose because you have a rash, you and your doctor should talk about prescribing another HIV-1 medicine for you instead of nevirapine.

Starting nevirapine extended-release tablets when this is the first time you are taking any form of nevirapine:

• Call your doctor right away if you get a skin rash during the first 14 days of nevirapine treatment.
• You should never take your starting dose for longer than 28 days. If after 28 days you are still receiving this starting dose because you have a rash, you and your doctor should talk about prescribing another HIV-1 medicine for you instead of nevirapine.
• Do not start nevirapine extended-release tablets if you have a rash.

Switching from nevirapine tablets or oral suspension to nevirapine extended-release tablets:

• Take nevirapine extended-release tablets 1 time a day as prescribed by your doctor.
• You may sometimes pass a soft mass in your stools (bowel movement) that looks like your nevirapine extended-release tablets. This will not affect the way your medicine works.

This Medication Guide has been approved by the U.S. Food and Drug Administration

The brands listed are trademarks of their respective owners.

Manufactured for:
Mylan Pharmaceuticals Inc.
Morgantown, WV 26505 U.S.A.

Manufactured by:
Mylan Laboratories Limited
Hyderabad — 500 096, India

75063966

Revised: 12/2017
MXA:NEV1:R4

NDC 0378-6950-77

Nevirapine
Extended-Release
Tablets, USP
100 mg

PHARMACIST: Dispense the accompanying
Medication Guide to each patient.

Rx only     90 Tablets

Each tablet contains:
Nevirapine, USP   100 mg

Usual Dosage: See accompanying
prescribing information.

Tablets must be swallowed whole and
must not be chewed, crushed, or divided.

Keep this and all medication out of
the reach of children.

Store at 20° to 25°C (68° to 77°F). [See
USP Controlled Room Temperature.]

Manufactured for:
Mylan Pharmaceuticals Inc.
Morgantown, WV 26505 U.S.A.

Made in India

Mylan.com

RMXA6950MM2

Dispense in a tight, light-resistant
container as defined in the USP
using a child-resistant closure.

Keep container tightly closed.

Code No.: MH/DRUGS/AD/089

Nevirapine Extended-release Tablets, Usp 100 mg Bottle Label (Image 01)

NDC 0378-4890-93

Nevirapine
Extended-Release
Tablets, USP
400 mg

PHARMACIST: Dispense the accompanying
Medication Guide to each patient.

Rx only     30 Tablets

Each tablet contains:
Nevirapine, USP    400 mg

Usual Dosage: See accompanying
prescribing information.

Tablets must be swallowed whole and
must not be chewed, crushed, or divided.

Keep this and all medication out of
the reach of children.

Store at 20° to 25°C (68° to 77°F). [See
USP Controlled Room Temperature.]

Manufactured for:
Mylan Pharmaceuticals Inc.
Morgantown, WV 26505 U.S.A.

Made in India

Mylan.com

RMXA4890H2

Dispense in a tight, light-resistant
container as defined in the USP
using a child-resistant closure.

Keep container tightly closed.

Code No.: MH/DRUGS/AD/089

Nevirapine Extended-release Tablets, Usp 400 mg Bottle Label (Image 04)