Other
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 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 is indicated in combination with other antiretroviral agents for the treatment of human immunodeficiency virus (HIV-1) infection in adults and pediatric patients 15 days and older [see Clinical Studies (14.1, 14.2].
Limitations of Use:
Based on serious and life-threatening hepatotoxicity observed in controlled and uncontrolled trials, nevirapine is 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 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 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 trials 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 trials 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.
* The interaction between nevirapine and the drug was evaluated in a clinical study. All other drug interactions shown are predicted. | ||
| Drug name | Effect on concentration of nevirapine or concomitant drug | Clinical comment |
| HIV Antiviral Agents: Protease Inhibitors (PIs) | ||
| Atazanavir/Ritonavir* | ↓ Atazanavir ↑ Nevirapine | Do not co-administer nevirapine with atazanavir because nevirapine substantially decreases atazanavir exposure and there is a potential risk for nevirapine-associated toxicity due to increased nevirapine exposures. |
| Fosamprenavir* Fosamprenavir /Ritonavir* | ↓ Amprenavir ↑ Nevirapine ↓ Amprenavir ↑ Nevirapine | Co-administration of nevirapine and fosamprenavir without ritonavir is not recommended. No dosing adjustments are required when nevirapine is co-administered with 700/100 mg of fosamprenavir/ ritonavir twice daily. The combination of nevirapine administered with fosamprenavir/ritonavir once daily has not been studied. |
| Indinavir* | ↓ Indinavir | The appropriate doses of this combination of indinavir and nevirapine with respect to efficacy and safety have not been established. |
| Lopinavir/Ritonavir* | ↓ Lopinavir | Dosing in adult patients:A dose adjustment of lopinavir/ritonavir to 500/125 mg tablets twice daily or 533/133 mg (6.5 mL) oral solution twice daily is recommended when used in combination with nevirapine. Neither lopinavir/ritonavir tablets nor oral solution should be administered once daily in combination with nevirapine. Dosing in pediatric patients:Please refer to the Kaletra® prescribing information for dosing recommendations based on body surface area and body weight. Neither lopinavir/ritonavir tablets nor oral solution should be administered once daily in combination with nevirapine. |
| Nelfinavir* | ↓ Nelfinavir M8 Metabolite ↓ Nelfinavir Cmin | The appropriate doses of the combination of nevirapine and nelfinavir with respect to safety and efficacy have not been established. |
| Saquinavir /ritonavir | The interaction between nevirapine and saquinavir/ritonavir has not been evaluated | The appropriate doses of the combination of nevirapine and saquinavir/ritonavir with respect to safety and efficacy have not been established. |
| HIV Antiviral Agents: Non-Nucleoside Reverse Transcriptase Inhibitors (NNRTIs) | ||
| Efavirenz* Delavirdine Etravirine Rilpivirine | ↓ Efavirenz | The appropriate doses of these combinations with respect to safety and efficacy have not been established. Plasma concentrations may be altered. Nevirapine should not be coadministered with another NNRTI as this combination has not been shown to be beneficial. |
| Hepatitis C Antiviral Agents | ||
| Boceprevir | Plasma concentrations of boceprevir may be decreased due to induction of CYP3A4/5 by nevirapine. | Nevirapine and boceprevir should not be coadministered because decreases in boceprevir plasma concentrations may result in a reduction in efficacy. |
| Telaprevir | Plasma concentrations of telaprevir may be decreased due to induction of CYP3A4 by nevirapine and plasma concentrations of nevirapine may be increased due to inhibition of CYP3A4 by telaprevir. | Nevirapine and telaprevir should not be coadministered because changes in plasma concentrations of nevirapine, telaprevir, or both may result in a reduction in telaprevir efficacy or an increase in nevirapine- associated adverse events. |
| Other Agents | ||
| Analgesics: Methadone* | ↓ Methadone | Methadone levels were decreased; increased dosages may be required to prevent symptoms of opiate withdrawal. Methadone-maintained patients beginning nevirapine therapy should be monitored for evidence of withdrawal and methadone dose should be adjusted accordingly. |
| Antiarrhythmics: Amiodarone, disopyramide, lidocaine | Plasma concentrations may be decreased. | Appropriate doses for this combination have not been established. |
| Antibiotics : Clarithromycin* Rifabutin* Rifampin* | ↓ Clarithromycin ↑ 14-OH clarithromycin ↑ Rifabutin ↓ Nevirapine | Clarithromycin exposure was significantly decreased by nevirapine; however, 14-OH metabolite concentrations were increased. Because clarithromycin active metabolite has reduced activity against Mycobacterium avium-intracellulare complex, overall activity against this pathogen may be altered. Alternatives to clarithromycin, such as azithromycin, should be considered. Rifabutin and its metabolite concentrations were moderately increased. Due to high intersubject variability, however, some patients may experience large increases in rifabutin exposure and may be at higher risk for rifabutin toxicity. Therefore, caution should be used in concomitant administration. Nevirapine and rifampin should not be administered concomitantly because decreases in nevirapine plasma concentrations may reduce the efficacy of the drug. Physicians needing to treat patients co- infected with tuberculosis and using a nevirapine- containing regimen may use rifabutin instead. |
| Anticonvulsants: Carbamazepine, clonazepam, ethosuximide | Plasma concentrations of nevirapine and the anticonvulsant may be decreased. | Use with caution and monitor virologic response and levels of anticonvulsants. |
| Antifungals: Fluconazole* Ketoconazole* Itraconazole | ↑ Nevirapine ↓ Ketoconazole ↓ Itraconazole | Because of the risk of increased exposure to nevirapine, caution should be used in concomitant administration, and patients should be monitored closely for nevirapine -associated adverse events. Nevirapine and ketoconazole should not be administered concomitantly because decreases in ketoconazole plasma concentrations may reduce the efficacy of the drug. Nevirapine and itraconazole should not be administered concomitantly due to a potential decreases in itraconazole plasma concentrations that may reduce efficacy of the drug. |
| Antithrombotics: Warfarin | Plasma concentrations may be increased. | Potential effect on anticoagulation. Monitoring of anticoagulation levels is recommended. |
| Calcium channel blockers: Diltiazem, nifedipine, verapamil | Plasma concentrations may be decreased. | Appropriate doses for these combinations have not been established. |
| Cancer chemotherapy: Cyclophosphamide | Plasma concentrations may be decreased. | Appropriate doses for this combination have not been established. |
| Ergot alkaloids: Ergotamine | Plasma concentrations may be decreased. | Appropriate doses for this combination have not been established. |
| Immunosuppressants: Cyclosporine, tacrolimus, sirolimus | Plasma concentrations may be decreased. | Appropriate doses for these combinations have not been established. |
| Motility agents: Cisapride | Plasma concentrations may be decreased. | Appropriate doses for this combination have not been established. |
| Opiate agonists: Fentanyl | Plasma concentrations may be decreased. | Appropriate doses for this combination have not been established. |
| Oral contraceptives: Ethinyl estradiol and Norethindrone* | ↓ Ethinyl estradiol ↓ Norethindrone | Despite lower ethinyl estradiol and norethindrone exposures when coadministered with nevirapine, literature reports suggest that nevirapine has no effect on pregnancy rates among HIV-infected women on combined oral contraceptives. When coadministered with nevirapine, no dose adjustment of ethinyl estradiol or norethindrone is needed when used in combination for contraception. When these oral contraceptives are used for hormonal regulation during nevirapine therapy, the therapeutic effect of the hormonal therapy should be monitored. |
There is no known antidote for nevirapine overdosage. Cases of 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 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 is a white to off-white crystalline powder with the molecular weight of 266.30 and the molecular formula C15H14N4O. Nevirapine has the following structural formula:
Nevirapine Tablets are for oral administration. Each tablet contains 200 mg of nevirapine and the inactive ingredients microcrystalline cellulose (Avicel pH 101) corn starch, lactose monohydrate (lactose 200), sodium starch glycolate (Primojel), magnesium stearate.
Nevirapine Tablets USP, 200 mg, are white oval shaped biconvex tablets (9.3 mm x 19.10 mm) with central break line on one side and 'N' debossed on the other side.
Nevirapine Tablets USP, 200 mg are available as follows:
Bottle of 60 tablets (NDC 53104 0166 2)
Bottle of 1000 tablets (NDC 53104 0166 6)
Storage
Store at 20°C-25°C (68°F-77°F) [See USP Controlled room temperature]. Keep out of the reach of children.