Data from FDA (Food and Drug Administration, USA) - Curated by Marshall Pearce - Last updated 28 September 2017

Indication(s)

1 INDICATIONS AND USAGE Abacavir and lamivudine tablet, a combination of abacavir and lamivudine, both nucleoside analogue HIV-1 reverse transcriptase inhibitors, is indicated in combination with other antiretroviral agents for the treatment of HIV-1 infection. ( 1) Abacavir and lamivudine tablets, in combination with other antiretroviral agents, are indicated for the treatment of human immunodeficiency virus type 1 (HIV-1) infection.

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Advisory information

contraindications
4 CONTRAINDICATIONS Presence of HLA-B*5701 allele. ( 4) Prior hypersensitivity reaction to abacavir or lamivudine. ( 4) Moderate or severe hepatic impairment. ( 4, 8.7) Abacavir and lamivudine tablets are contraindicated in patients: who have the HLA-B*5701 allele [see WARNINGS AND PRECAUTIONS ( 5.1)]. with prior hypersensitivity reaction to abacavir [see WARNINGS AND PRECAUTIONS ( 5.1)] or lamivudine. with moderate or severe hepatic impairment [see USE IN SPECIFIC POPULATIONS ( 8.7)].
Adverse reactions
6 ADVERSE REACTIONS The most commonly reported adverse reactions of at least moderate intensity (incidence greater than 5%) in an adult HIV-1 clinical trial were drug hypersensitivity, insomnia, depression/depressed mood, headache/migraine, fatigue/malaise, dizziness/vertigo, nausea, and diarrhea. ( 6.1) To report SUSPECTED ADVERSE REACTIONS, contact Lupin Pharmaceuticals, Inc. at 1-800-399-2561 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. The following adverse reactions are discussed in greater detail in other sections of the labeling: Serious and sometimes fatal hypersensitivity reaction. [see BOXED WARNING, WARNINGS AND PRECAUTIONS ( 5.1)] . Lactic acidosis and severe hepatomegaly with steatosis [see BOXED WARNING, WARNINGS AND PRECAUTIONS ( 5.2)] . Exacerbations of hepatitis B [see BOXED WARNING, WARNINGS AND PRECAUTIONS ( 5.3)] . Hepatic decompensation in patients co-infected with HIV-1 and Hepatitis C [see WARNINGS AND PRECAUTIONS ( 5.4)] . Immune reconstitution syndrome [see WARNINGS AND PRECAUTIONS ( 5.5)]. Fat redistribution [see WARNINGS AND PRECAUTIONS ( 5.6)]. Myocardial infarction [see WARNINGS AND PRECAUTIONS ( 5.7)]. 6.1 Clinical Trials Experience in Adult Subjects Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared with rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice. Serious and Fatal Abacavir-Associated Hypersensitivity Reactions In clinical trials, serious and sometimes fatal hypersensitivity reactions have occurred with abacavir, a component of abacavir and lamivudine tablets [see BOXED WARNING, WARNINGS AND PRECAUTIONS (5.1)]. These reactions have been characterized by 2 or more of the following signs or symptoms: (1) fever; (2) rash; (3) gastrointestinal symptoms (including nausea, vomiting, diarrhea, or abdominal pain); (4) constitutional symptoms (including generalized malaise, fatigue, or achiness); (5) respiratory symptoms (including dyspnea, cough, or pharyngitis). Almost all abacavir hypersensitivity reactions include fever and/or rash as part of the syndrome. Other signs and symptoms have included lethargy, headache, myalgia, edema, arthralgia, and paresthesia. Anaphylaxis, liver failure, renal failure, hypotension, adult respiratory distress syndrome, respiratory failure, myolysis, and death have occurred in association with these hypersensitivity reactions. Physical findings have included lymphadenopathy, mucous membrane lesions (conjunctivitis and mouth ulcerations), and maculopapular or urticarial rash (although some patients had other types of rashes and others did not have a rash). There were reports of erythema multiforme. Laboratory abnormalities included elevated liver chemistries, elevated creatine phosphokinase, elevated creatinine, and lymphopenia and abnormal chest x-ray findings (predominantly infiltrates, which were localized). Additional Adverse Reactions with Use of Abacavir and Lamivudine Tablets: Therapy-Naive Adults: Treatment-emergent clinical adverse reactions (rated by the investigator as moderate or severe) with greater than or equal to 5% frequency during therapy with ZIAGEN 600 mg once daily or ZIAGEN 300 mg twice daily, both in combination with lamivudine 300 mg once daily and efavirenz 600 mg once daily, are listed in Table 1. Table 1. Treatment-Emergent (All Causality) Adverse Reactions of at Least Moderate Intensity (Grades 2 to 4, Greater than or Equal to 5% Frequency) in Therapy-Naive Adults (CNA30021) through 48 Weeks of Treatment aSubjects receiving ZIAGEN 600 mg once daily, experienced a significantly higher incidence of severe drug hypersensitivity reactions and severe diarrhea compared with subjects who received ZIAGEN 300 mg twice daily. Five percent (5%) of subjects receiving ZIAGEN 600 mg once daily had severe drug hypersensitivity reactions compared with 2% of subjects receiving ZIAGEN 300 mg twice daily. Two percent (2%) of subjects receiving ZIAGEN 600 mg once daily had severe diarrhea while none of the subjects receiving ZIAGEN 300 mg twice daily had this event. bCNA30024 was a multi-center, double-blind, controlled trial in which 649 HIV-1-infected, therapy-naive adults were randomized and received either ZIAGEN (300 mg twice daily), EPIVIR (150 mg twice daily), and efavirenz (600 mg once daily); or zidovudine (300 mg twice daily), EPIVIR (150 mg twice daily), and efavirenz (600 mg once daily). CNA30024 used double-blind ascertainment of suspected hypersensitivity reactions. During the blinded portion of the trial, suspected hypersensitivity to abacavir was reported by investigators in 9% of 324 subjects in the abacavir group and 3% of 325 subjects in the zidovudine group. Adverse Event ZIAGEN 600 mg q . d . plus EPIVIR plus Efavirenz ( n = 384 ) ZIAGEN 300 mg b . i . d . plus EPIVIR plus Efavirenz ( n = 386 ) Drug hypersensitivity a , b 9% 7% Insomnia 7% 9% Depression/Depressed mood 7% 7% Headache/Migraine 7% 6% Fatigue/Malaise 6% 8% Dizziness/Vertigo 6% 6% Nausea 5% 6% Diarrhea a 5% 6% Rash 5% 5% Pyrexia 5% 3% Abdominal pain/gastritis 4% 5% Abnormal dreams 4% 5% Anxiety 3% 5% Laboratory Abnormalities Laboratory abnormalities observed in clinical trials of ZIAGEN were anemia, neutropenia, liver function test abnormalities, and elevations of CPK, blood glucose, and triglycerides. Additional laboratory abnormalities observed in clinical trials of EPIVIR were thrombocytopenia and elevated levels of bilirubin, amylase, and lipase. The frequencies of treatment-emergent laboratory abnormalities were comparable between treatment groups in CNA30021. Other Adverse Events In addition to adverse reactions listed above, other adverse events observed in the expanded access program for abacavir were pancreatitis and increased GGT. 6.3 Clinical Trials Experience in Pediatric Subjects The safety of once-daily compared with twice-daily dosing of abacavir and lamivudine, administered as either single products or as abacavir and lamivudine tablets, was assessed in the ARROW trial (n = 336). Primary safety assessment in the ARROW (COL105677) trial was based on Grade 3 and Grade 4 adverse events. The frequency of Grade 3 and 4 adverse events was similar among subjects randomized to once-daily dosing compared with subjects randomized to twice-daily dosing. One event of Grade 4 hepatitis in the once-daily cohort was considered as uncertain causality by the investigator and all other Grade 3 or 4 adverse events were considered not related by the investigator. No additional safety issues were identified in pediatric subjects receiving abacavir and lamivudine once-daily compared with historical data in adults [see ADVERSE REACTIONS ( 6.1)] . 6.2 Postmarketing Experience The following adverse reactions have been identified during postmarketing use. Because these reactions are reported voluntarily from a population of unknown size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. Abacavir Cardiovascular: Myocardial infarction. Skin: Suspected Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) have been reported in patients receiving abacavir primarily in combination with medications known to be associated with SJS and TEN, respectively. Because of the overlap of clinical signs and symptoms between hypersensitivity to abacavir and SJS and TEN, and the possibility of multiple drug sensitivities in some patients, abacavir should be discontinued and not restarted in such cases. There have also been reports of erythema multiforme with abacavir use [see ADVERSE REACTIONS ( 6.1)] . Abacavir and Lamivudine Body as a Whole: Redistribution/accumulation of body fat [see WARNINGS AND PRECAUTIONS ( 5.6)] . Digestive: Stomatitis. Endocrine and Metabolic: Hyperglycemia. General: Weakness. Hemic and Lymphatic: Aplastic anemia, anemia (including pure red cell aplasia and severe anemias progressing on therapy), lymphadenopathy, splenomegaly. Hepatic: Lactic acidosis and hepatic steatosis [see WARNINGS AND PRECAUTIONS ( 5.2)] , posttreatment exacerbation of hepatitis B [see WARNINGS AND PRECAUTIONS ( 5.3)] . Hypersensitivity: Sensitization reactions (including anaphylaxis), urticaria. Musculoskeletal: Muscle weakness, CPK elevation, rhabdomyolysis. Nervous: Paresthesia, peripheral neuropathy, seizures. Respiratory: Abnormal breath sounds/wheezing. Skin: Alopecia, erythema multiforme, Stevens-Johnson syndrome.

Usage information

Dosing and administration
2 DOSAGE AND ADMINISTRATION Before initiating abacavir and lamivudine tablets, screen for the HLA-B*5701 allele because abacavir and lamivudine tablets contain abacavir. ( 2.1) Adults: One tablet orally once daily. ( 2.2) Pediatric patients weighing at least 25 kg: One tablet daily. ( 2.3) Because abacavir and lamivudine tablets is a fixed-dose tablet and cannot be dose adjusted, Abacavir and lamivudine tablets is not recommended in patients requiring dosage adjustment or patients with hepatic impairment. ( 2.4, 4) 2.1 Screening for HLA-B*5701 Allele Prior to Starting Abacavir and Lamivudine Tablets Screen for the HLA-B*5701 allele prior to initiating therapy with abacavir and lamivudine tablets [see BOXED WARNING, WARNINGS AND PRECAUTIONS ( 5.1)] . 2.2 Recommended Dosage for Adult Patients The recommended dosage of abacavir and lamivudine tablets for adults is one tablet taken orally once daily, in combination with other antiretroviral agents, with or without food. 2.3 Recommended Dosage for Pediatric Patients The recommended oral dose of abacavir and lamivudine tablets for pediatric patients weighing at least 25 kg is one tablet daily in combination with other antiretroviral agents [see CLINICAL STUDIES ( 14.2)] . Before prescribing abacavir and lamivudine tablets, pediatric patients should be assessed for the ability to swallow tablets. 2.4 Not Recommended Due to Lack of Dosage Adjustment Because abacavir and lamivudine tablet is a fixed-dose tablet and cannot be dose adjusted, abacavir and lamivudine tablets are not recommended for: patients with creatinine clearance less than 50 mL per minute [see USE IN SPECIFIC POPULATIONS ( 8.6)] . patients with mild hepatic impairment. Abacavir and lamivudine tablets is contraindicated in patients with moderate or severe hepatic impairment [see CONTRAINDICATIONS ( 4), USE IN SPECIFIC POPULATIONS ( 8.7)] . Use of EPIVIR® (lamivudine) oral solution or tablets and ZIAGEN® (abacavir) oral solution may be considered.
Use in special populations
8 USE IN SPECIFIC POPULATIONS Lactation: Women infected with HIV should be instructed not to breastfeed due to potential for HIV transmession. ( 8.2) 8.1 Pregnancy Pregnancy Exposure Registry There is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to abacavir and lamivudine tablets during pregnancy. Healthcare providers are encouraged to register patients by calling the Antiretroviral Pregnancy Registry (APR) at 1-800-258-4263. Risk Summary Available data from the (APR) show no difference in the overall risk of birth defects for abacavir or lamivudine compared with the background rate for birth defects of 2.7% in the Metropolitan Atlanta Congenital Defects Program (MACDP) reference population [see Data]. The APR uses the MACDP as the U.S. reference population for birth defects in the general population. The MACDP evaluates women and infants from a limited geographic area and does not include outcomes for births that occurred at less than 20 weeks gestation. 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% to 20%. The background risk for major birth defects and miscarriage for the indicated population is unknown. In animal reproduction studies, oral administration of abacavir to pregnant rats during organogenesis resulted in fetal malformations and other embryonic and fetal toxicities at exposures 35 times the human exposure (AUC) at the recommended clinical daily dose. However, no adverse developmental effects were observed following oral administration of abacavir to pregnant rabbits during organogenesis, at exposures approximately 9 times the human exposure (AUC) at the recommended clinical dose. Oral administration of lamivudine to pregnant rabbits during organogenesis resulted in embryolethality at systemic exposure (AUC) similar to the recommended clinical dose; however, no adverse development effects were observed with oral administration of lamivudine to pregnant rats during organogenesis at plasma concentrations (Cmax) 35 times the recommended clinical dose [see Data].. Data Human Data: Abacavir Based on prospective reports to the APR of over 2,000 exposures to abacavir during pregnancy resulting in live births (including over 1,000 exposed in the first trimester), there was no difference between the overall risk of birth defects for abacavir compared with the background birth defect rate of 2.7% in the U.S. reference population of the MACDP. The prevalence of defects in live births was 2.9% (95% CI: 2.0% to 4.1%) following first trimester exposure to abacavir-containing regimens and 2.7% (95% CI: 1.9% to 3.7%) following second/third trimester exposure to abacavir-containing regimens. Abacavir has been shown to cross the placenta and concentrations in neonatal plasma at birth were essentially equal to those in maternal plasma at delivery [see CLINICAL PHARMACOLOGY ( 12.3)]. Lamivudine Based on prospective reports to the APR of over 11,000 exposures to lamivudine during pregnancy resulting in live births (including over 4,500 exposed in the first trimester), there was no difference between the overall risk of birth defects for lamivudine compared with the background birth defect rate of 2.7% in the U.S. reference population of the MACDP. The prevalence of birth defects in live births was 3.1% (95% CI: 2.6% to 3.6%) following first trimester exposure to lamivudine-containing regimens and 2.8% (95% CI: 2.5%, 3.3%) following second/third trimester exposure to lamivudine-containing regimens. Lamivudine pharmacokinetics were studied in pregnant women during 2 clinical trials conducted in South Africa. The trials assessed pharmacokinetics in 16 women at 36 weeks gestation using 150 mg lamivudine twice daily with zidovudine, 10 women at 38 weeks gestation using 150 mg lamivudine twice daily with zidovudine, and 10 women at 38 weeks gestation using lamivudine 300 mg twice daily without other antiretrovirals. These trials were not designed or powered to provide efficacy information. Lamivudine concentrations were generally similar in maternal, neonatal, and umbilical cord serum samples. In a subset of subjects, amniotic fluid specimens were collected following natural rupture of membranes and confirmed that lamivudine crosses the placenta in humans. Based on limited data at delivery, median (range) amniotic fluid concentrations of lamivudine were 3.9 (1.2 to 12.8)–fold greater compared with paired maternal serum concentration (n = 8). Animal Data: Abacavir Abacavir was administered orally to pregnant rats (at 100, 300, and 1,000 mg per kg per day) and rabbits (at 125, 350, or 700 mg per kg per day) during organogenesis (on gestation Days 6 through 17 and 6 through 20, respectively). Fetal malformations (increased incidences of fetal anasarca and skeletal malformations) or developmental toxicity (decreased fetal body weight and crown-rump length) were observed in rats at doses up to 1,000 mg per kg per day, resulting in exposures approximately 35 times the human exposure (AUC) at the recommended daily dose. No developmental effects were observed in rats at 100 mg per kg per day, resulting in exposures (AUC) 3.5 times the human exposure at the recommended daily dose. In a fertility and early embryo-fetal development study conducted in rats (at 60, 160, or 500 mg per kg per day), embryonic and fetal toxicities (increased resorptions, decreased fetal body weights) or toxicities to the offspring (increased incidence of stillbirth and lower body weights) occurred at doses up to 500 mg per kg per day. No developmental effects were observed in rats at 60 mg per kg per day, resulting in exposures (AUC) approximately 4 times the human exposure at the recommended daily dose. Studies in pregnant rats showed that abacavir is transferred to the fetus through the placenta. In pregnant rabbits, no developmental toxicities and no increases in fetal malformations occurred at up to the highest dose evaluated, resulting in exposures (AUC) approximately 9 times the human exposure at the recommended dose. Lamivudine Lamivudine was administered orally to pregnant rats (at 90, 600, and 4,000 mg per kg per day) and rabbits (at 90, 300 and 1,000 mg per kg per day and at 15, 40, and 90 mg per kg per day) during organogenesis (on gestation Days 7 through 16 [rat] and 8 through 20 [rabbit]). No evidence of fetal malformations due to lamivudine was observed in rats and rabbits at doses producing plasma concentrations (C max) approximately 35 times higher than human exposure at the recommended daily dose. Evidence of early embryolethality was seen in the rabbit at systemic exposures (AUC) similar to those observed in humans, but there was no indication of this effect in the rat at plasma concentrations (C max) 35 times higher than human exposure at the recommended daily dose. Studies in pregnant rats showed that lamivudine is transferred to the fetus through the placenta. In the pre-and postnatal development study in rats, lamivudine was administered orally at doses of 180, 900, and 4,000 mg per kg per day from gestation Day 6 through postnatal Day 20). In the study, development of the offspring, including fertility and reproductive performance, were not affected by the maternal administration of lamivudine. 8.2 Lactation Risk Summary The Centers for Disease Control and Prevention recommend that HIV-1-infected mothers in the United States not breastfeed their infants to avoid risking postnatal transmission of HIV-1 infection. Abacavir and lamivudine are present in human milk. There is no information on the effects of abacavir and lamivudine on the breastfed infant or the effects of the drug 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 a breastfed infant, instruct mothers not to breastfeed if they are receiving abacavir and lamivudine tablets. 8.4 Pediatric Use The dosing recommendations in this population are based on the safety and efficacy established in a controlled trial conducted using either the combination of EPIVIR and ZIAGEN or abacavir and lamivudine tablets [see DOSAGE AND ADMINISTRATION ( 2.3), ADVERSE REACTIONS ( 6.2), CLINICAL STUDIES ( 14.2)] . In pediatric patients weighing less than 25 kg, use of abacavir and lamivudine as single products is recommended to achieve appropriate dosing. 8.5 Geriatric Use Clinical trials of abacavir and lamivudine did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects. In general, caution should be exercised in the administration of abacavir and lamivudine tablets in elderly patients reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy [see DOSAGE AND ADMINISTRATION ( 2.4), USE IN SPECIFIC POPULATIONS ( 8.6, 8.7)]. 8.6 Patients with Impaired Renal Function Abacavir and lamivudine tablets is not recommended for patients with creatinine clearance less than 50 mL per min because abacavir and lamivudine tablets is a fixed-dose combination and the dosage of the individual components cannot be adjusted. If a dose reduction of lamivudine, a component of abacavir and lamivudine tablets, is required for patients with creatinine clearance less than 50 mL per min, then the individual components should be used [see CLINICAL PHARMACOLOGY ( 12.3)]. 8.7 Patients with Impaired Hepatic Function Abacavir and lamivudine tablet is a fixed-dose combination and the dosage of the individual components cannot be adjusted. If a dose reduction of abacavir, a component of abacavir and lamivudine tablets, is required for patients with mild hepatic impairment (Child-Pugh Class A), then the individual components should be used [see CLINICAL PHARMACOLOGY ( 12.3)] . The safety, efficacy, and pharmacokinetic properties of abacavir have not been established in patients with moderate (Child-Pugh Class B) or severe (Child-Pugh Class C) hepatic impairment; therefore, abacavir and lamivudine tablets are contraindicated in these patients [see CONTRAINDICATIONS ( 4)].

Interactions

7 DRUG INTERACTIONS Methadone: An increased methadone dose may be required in a small number of patients. ( 7.1) 7.1 Methadone In a trial of 11 HIV-1-infected subjects receiving methadone-maintenance therapy with 600 mg of ZIAGEN twice daily (twice the currently recommended dose), oral methadone clearance increased [see CLINICAL PHARMACOLOGY ( 12.3)] . This alteration will not result in a methadone dose modification in the majority of patients; however, an increased methadone dose may be required in a small number of patients.

More information

Category Value
Authorisation number ANDA204990
Agency product number J220T4J9Q2
Orphan designation No
Product NDC 70518-0715
Date Last Revised 28-08-2017
Type HUMAN PRESCRIPTION DRUG
RXCUI 602393
Marketing authorisation holder REMEDYREPACK INC.
Warnings WARNING: HYPERSENSITIVITY REACTIONS, LACTIC ACIDOSIS AND SEVERE HEPATOMEGALY WITH STEATOSIS, and EXACERBATIONS OF HEPATITIS B WARNING: HYPERSENSITIVITY REACTIONS, LACTIC ACIDOSIS AND SEVERE HEPATOMEGALY WITH STEATOSIS, and EXACERBATIONS OF HEPATITIS B See full prescribing information for complete boxed warning. Hypersensitivity Reactions Serious and sometimes fatal hypersensitivity reactions have occurred with abacavir-containing products. ( 5.1) Hypersensitivity to abacavir is a multi-organ clinical syndrome. ( 5.1) Patients who carry the HLA-B*5701 allele are at a higher risk of experiencing a hypersensitivity reaction to abacavir. ( 5.1) Abacavir and lamivudine tablets are contraindicated in patients with a prior hypersensitivity reaction to abacavir and in HLA-B*5701-positive patients. ( 4) Discontinue abacavir and lamivudine tablets as soon as a hypersensitivity reaction is suspected. Regardless of HLA-B*5701 status, permanently discontinue abacavir and lamivudine tablets if hypersensitivity cannot be ruled out, even when other diagnoses are possible. ( 5.1) Following a hypersensitivity reaction to abacavir and lamivudine tablets, NEVER restart abacavir and lamivudine tablets or any other abacavir-containing product. ( 5.1) Lactic Acidosis and Severe Hepatomegaly with Steatosis Lactic acidosis and severe hepatomegaly with steatosis, including fatal cases, have been reported with the use of nucleoside analogues. ( 5.2) Exacerbations of Hepatitis B Severe acute exacerbations of hepatitis B have been reported in patients who are co-infected with hepatitis B virus (HBV) and human immunodeficiency virus (HIV-1) and have discontinued lamivudine, a component of abacavir and lamivudine tablets. Monitor hepatic function closely in these patients and, if appropriate, initiate anti-hepatitis B treatment. ( 5.3) Hypersensitivity Reactions Serious and sometimes fatal hypersensitivity reactions, with multiple organ involvement, have occurred with abacavir, a component of abacavir and lamivudine Tablets. Patients who carry the HLA-B*5701 allele are at a higher risk of a hypersensitivity reaction to abacavir; although, hypersensitivity reactions have occurred in patients who do not carry the HLA-B*5701 allele [see WARNINGS AND PRECAUTIONS ( 5.1)] . Abacavir and lamivudine tablets are contraindicated in patients with a prior hypersensitivity reaction to abacavir and in HLA-B*5701-positive patients [see CONTRAINDICATIONS ( 4), WARNINGS AND PRECAUTIONS ( 5.1)] . All patients should be screened for the HLA-B*5701 allele prior to initiating therapy with abacavir and lamivudine tablets or reinitiation of therapy with abacavir and lamivudine tablets, unless patients have a previously documented HLA-B*5701 allele assessment. Discontinue Abacavir and lamivudine tablets immediately if a hypersensitivity reaction is suspected, regardless of HLA-B*5701 status and even when other diagnoses are possible [see CONTRAINDICATIONS ( 4), WARNINGS AND PRECAUTIONS ( 5.1)] . Following a hypersensitivity reaction to abacavir and lamivudine tablets, NEVER restart abacavir and lamivudine tablets or any other abacavir-containing product because more severe symptoms, including death, can occur within hours. Similar severe reactions have also occurred rarely following the reintroduction of abacavir-containing products in patients who have no history of abacavir hypersensitivity [see WARNINGS AND PRECAUTIONS ( 5.1)] . Lactic Acidosis and Severe Hepatomegaly with Steatosis Lactic acidosis and severe hepatomegaly with steatosis, including fatal cases, have been reported with the use of nucleoside analogues and other antiretrovirals. Discontinue abacavir and lamivudine tablets if clinical or laboratory findings suggestive of lactic acidosis or pronounced hepatotoxicity occur [see WARNINGS AND PRECAUTIONS ( 5.2)] . Exacerbations of Hepatitis B Severe acute exacerbations of hepatitis B have been reported in patients who are co-infected with hepatitis B virus (HBV) and human immunodeficiency virus (HIV-1) and have discontinued lamivudine, which is a component of abacavir and lamivudine tablets. Hepatic function should be monitored closely with both clinical and laboratory follow-up for at least several months in patients who discontinue abacavir and lamivudine tablets and are co-infected with HIV-1 and HBV. If appropriate, initiation of anti-hepatitis B therapy may be warranted [see WARNINGS AND PRECAUTIONS ( 5.3)] .