1 tablet orally every 12 hours
(Not approved by FDA)
Centers for Disease Control and Prevention recommendations: 1 tablet orally every 12 hours
Duration: 28 days
Prophylaxis should be initiated as soon as possible, within 72 hours of exposure. An alternative regimen recommended for nonoccupational postexposure HIV prophylaxis includes abacavir plus lamivudine plus zidovudine. This triple nucleoside reverse transcriptase inhibitor (NRTI) regimen is recommended only when a nonnucleoside reverse transcriptase inhibitor (NNRTI)-based or a protease inhibitor (PI)-based regimen cannot or should not be used.
Adolescents, 40 kg or more: 1 tablet orally every 12 hours
This fixed-dose tablet is not recommended for adolescents who weigh less than 40 kg.
CrCl less than 50 mL/min: Not recommended.
Abacavir/lamivudine/zidovudine is contraindicated in patients with hepatic impairment.
Abacavir/lamivudine/zidovudine should not be prescribed for patients requiring dose adjustment, such as those experiencing dose-limiting adverse events.
Serious and sometimes fatal hypersensitivity reactions have been associated with abacavir therapy and usually appear within the first 6 weeks of treatment. Patients with the HLA-B*5701 allele are at increased risk of hypersensitivity reaction to abacavir; therefore, screening for the HLA-B*5701 allele is recommended prior to starting abacavir treatment. Therapy with an abacavir-containing regimen is not recommended for HLA-B*5701-positive patients and should be considered only with close medical supervision under exceptional conditions where potential benefit outweighs the risk. Considerably less frequently, HLA-B*5701-negative patients may experience hypersensitivity reaction with abacavir. Frequently observed signs and symptoms include, but are not limited to, fever, skin rash, fatigue, nausea, vomiting, diarrhea, abdominal pain, malaise, pharyngitis, dyspnea, and cough. This drug should be discontinued as soon as a hypersensitivity reaction is suspected and should not be restarted because more severe symptoms will occur within hours and may include life-threatening hypotension and death.
Severe or fatal hypersensitivity reactions can also occur within hours after restarting abacavir in patients who have no identified history or unrecognized symptoms of this reaction. Screening for the HLA-B*5701 allele is also recommended prior to restarting abacavir treatment in patients whose HLA-B*5701 status is unknown. Abacavir therapy should be permanently discontinued if hypersensitivity cannot be ruled out, even when other diagnoses are possible, to minimize the risk of a life-threatening hypersensitivity reaction. Once-daily dosing of abacavir was associated with more severe reactions in a clinical study.
The manufacturer's Medication Guide and Warning Card with information about the abacavir hypersensitivity reaction must be dispensed with each new and refill prescription.
Zidovudine has been associated with hematologic toxicity (including neutropenia and severe anemia), particularly in patients with advanced HIV-1 disease. Abacavir/lamivudine/zidovudine should be used with caution in patients with bone marrow suppression indicated by granulocyte count below 1000 cells/mm3 or hemoglobin less than 9.5 g/dL. Frequent blood counts are strongly recommended in patients with advanced HIV-1 disease treated with abacavir/lamivudine/zidovudine. Periodic blood counts are recommended for HIV-1-infected individuals and patients with asymptomatic or early HIV-1 disease.
Lactic acidosis and severe hepatomegaly with steatosis, including fatal cases, have been reported with the use of nucleoside analogs alone or in combination with other antiretroviral agents. Risk factors may include female gender, obesity, and prolonged nucleoside exposure. Caution is recommended in patients with risk factors for liver disease; however, cases have also been reported in patients with no known risk factors. Treatment with abacavir/lamivudine/zidovudine should be suspended in any patient who develops clinical or laboratory findings suggestive of lactic acidosis or pronounced hepatotoxicity.
In clinical trials in non-HIV-1-infected patients treated with lamivudine for chronic hepatitis B virus (HBV) infection, posttreatment exacerbations of hepatitis have occurred once lamivudine was discontinued. While most cases were self-limited, some fatalities have been reported. Similar events have occurred during postmarketing experience after patients coinfected with HIV-1 and HBV switched from lamivudine-containing HIV-1 treatment regimens to non-lamivudine-containing regimens. Close monitoring of hepatic function with clinical and laboratory follow-up is recommended for at least several months after stopping treatment. If appropriate, resumption of antihepatitis B therapy may be necessary.
Safety and efficacy of lamivudine have not been established in patients who are coinfected with HIV-1 and HBV.
Hepatic decompensation, sometimes fatal, has occurred in HIV-1/HCV coinfected patients receiving combination antiretroviral therapy for HIV-1 and interferon alfa with or without ribavirin. Patients receiving interferon alfa with or without ribavirin and abacavir/lamivudine/zidovudine should be closely monitored for treatment-associated toxicities, especially hepatic decompensation, neutropenia, and anemia. Discontinuation of abacavir/lamivudine/zidovudine should be considered as medically appropriate. Dose reduction or discontinuation of interferon alfa, ribavirin or both should be considered if worsening clinical toxicities are observed, including hepatic decompensation (Child Pugh greater than 6).
Immune reconstitution syndrome has occurred during combination antiretroviral therapy. Patients responding to therapy may develop an inflammatory response to indolent or residual opportunistic infections and require evaluation and treatment.
The potential for HIV-1 cross-resistance among nucleoside reverse transcriptase inhibitors (NRTIs) exists but has not been fully explored. It is unknown what effect abacavir/lamivudine/zidovudine therapy will have on the activity of subsequently administered NRTIs. Selection of antiretroviral agents for a patient's medication regimen should be done carefully.
Abacavir/lamivudine/zidovudine should not be administered concurrently with other abacavir-containing, lamivudine-containing, and/or zidovudine-containing products (abacavir, lamivudine, zidovudine, abacavir-lamivudine, or lamivudine-zidovudine). Due to similar resistance profiles and lack of therapeutic benefit, the concomitant use of lamivudine and emtricitabine-containing medications is not recommended.
Abacavir/lamivudine/zidovudine is not intended for use in pediatric patients. It should not be administered to adolescents weighing less than 40 kg.
May be taken with or without food