Lamivudine

1 INDICATIONS AND USAGE Lamivudine oral solution, USP is a nucleoside analogue indicated in combination with other antiretroviral agents for the treatment of human immunodeficiency virus type 1 (HIV-1) infection. Limitations of Use: The dosage of this product is for HIV-1 and not for HBV. Lamivudine oral solution, USP is a nucleoside analogue reverse transcriptase inhibitor indicated in combination with other antiretroviral agents for the treatment of HIV-1 infection. Limitations of Use: The dosage of this product is for HIV-1 and not for HBV. ( 1 )

2 DOSAGE AND ADMINISTRATION Adults: 300 mg daily, administered as either 150 mg twice daily or 300 mg once daily. ( 2.1 ) Pediatric Patients Aged 3 Months and Older: Administered either once or twice daily. Dose should be calculated on body weight (kg) and should not exceed 300 mg daily. ( 2.2 ) Patients with Renal Impairment: Doses of lamivudine oral solution must be adjusted in accordance with renal function. ( 2.3 ) 2.1 Recommended Dosage for Adult Patients The recommended dosage of lamivudine oral solution in HIV-1-infected adults is 300 mg daily, administered as either 150 mg taken orally twice daily or 300 mg taken orally once daily with or without food. If lamivudine is administered to a patient infected with HIV-1 and HBV, the dosage indicated for HIV-1 therapy should be used as part of an appropriate combination regimen [see Warnings and Precautions (5.1) ]. 2.2 Recommended Dosage for Pediatric Patients Lamivudine scored tablet is the preferred formulation for HIV-1-infected pediatric patients who weigh at least 14 kg and for whom a solid dosage form is appropriate. Before prescribing lamivudine scored tablets, pediatric patients should be assessed for the ability to swallow tablets. For patients unable to safely and reliably swallow lamivudine tablets, the oral solution formulation may be prescribed [see Warnings and Precautions (5.5) ] . The recommended oral dosage of lamivudine tablets for HIV-1-infected pediatric patients is presented in Table 1. Table 1. Dosing Recommendations for Lamivudine Scored (150 mg) Tablets in Pediatric Patients Weight (kg) Twice-Daily Dosing Regimen Using Scored 150 mg Tablet Once-Daily Dosing Regimen a AM Dose PM Dose Total Daily Dose 14 to <20 1 tablet (150 mg) 1⁄2 tablet (75 mg) 1⁄2 tablet (75 mg) 150 mg ≥ 20 to <25 11⁄2 tablets (225 mg) 1⁄2 tablet (75 mg) 1 tablet (150 mg) 225 mg ≥25 2 tablets (300 mg) b 1 tablet (150 mg) 1 tablet (150 mg) 300 mg a Data regarding the efficacy of once-daily dosing is limited to subjects who transitioned from twice-daily dosing to once-daily dosing after 36 weeks of treatment [see Clinical Studies (14.2) ] . b Patients may alternatively take one 300 mg tablet, which is not scored. Oral Solution The recommended dosage of lamivudine oral solution in HIV-1-infected pediatric patients aged 3 months and older is 5 mg per kg taken orally twice daily or 10 mg per kg taken orally once daily (up to a maximum of 300 mg daily), administered in combination with other antiretroviral agents [see Clinical Pharmacology (12.3) ] . Consider HIV-1 viral load and CD4+ cell count/percentage when selecting the dosing interval for patients initiating treatment with oral solution [see Warnings and Precautions (5.5) , Clinical Pharmacology (12.3) ] . 2.3 Patients with Renal Impairment Dosing of lamivudine is adjusted in accordance with renal function. Dosage adjustments are listed in Table 2 [see Clinical Pharmacology (12.3) ] . Table 2. Adjustment of Dosage of Lamivudine in Adults and Adolescents (Greater than or Equal to 25 kg) in Accordance with Creatinine Clearance Creatinine Clearance (mL/min) Recommended Dosage of Lamivudine ≥50 150 mg twice daily or 300 mg once daily 30 to 49 150 mg once daily 15 to 29 150 mg first dose, then 100 mg once daily 5 to 14 150 mg first dose, then 50 mg once daily <5 50 mg first dose, then 25 mg once daily No additional dosing of lamivudine is required after routine (4-hour) hemodialysis or peritoneal dialysis. Although there are insufficient data to recommend a specific dose adjustment of lamivudine in pediatric patients with renal impairment, a reduction in the dose and/or an increase in the dosing interval should be considered.

3 DOSAGE FORMS AND STRENGTHS Lamivudine Oral Solution, USP contains 10 mg of lamivudine per 1 mL. The solution is a clear, colorless to pale yellow, strawberry flavored liquid. Oral Solution: 10 mg per mL ( 3 )

4 CONTRAINDICATIONS Lamivudine oral solution is contraindicated in patients with a previous hypersensitivity reaction to lamivudine. Lamivudine oral solution is contraindicated in patients with previous hypersensitivity reaction to lamivudine. ( 4 )

6 ADVERSE REACTIONS The following adverse reactions are discussed in other sections of the labeling: Exacerbations of hepatitis B [see Boxed Warning , Warnings and Precautions (5.1) ] . Lactic acidosis and severe hepatomegaly with steatosis [see Warnings and Precautions (5.2) ] . Pancreatitis [see Warnings and Precautions (5.3) ] . Immune reconstitution syndrome [see Warnings and Precautions (5.4) ] . The most common reported adverse reactions (incidence greater than or equal to 15%) in adults were headache, nausea, malaise and fatigue, nasal signs and symptoms, diarrhea, and cough. ( 6.1 ) The most common reported adverse reactions (incidence greater than or equal to 15%) in pediatric subjects were fever and cough. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Rising Health, LLC at 1-833-395-6928 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . 6.1 Clinical Trials Experience 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. The safety profile of lamivudine in adults is primarily based on 3,568 HIV-1-infected subjects in 7 clinical trials. The most common adverse reactions are headache, nausea, malaise, fatigue, nasal signs and symptoms, diarrhea, and cough. Selected clinical adverse reactions in greater than or equal to 5% of subjects during therapy with lamivudine 150 mg twice daily plus RETROVIR 200 mg 3 times daily for up to 24 weeks are listed in Table 3. Table 3. Selected Clinical Adverse Reactions (Greater than or Equal to 5% Frequency) in Four Controlled Clinical Trials (NUCA3001, NUCA3002, NUCB3001, NUCB3002) a Either zidovudine monotherapy or zidovudine in combination with zalcitabine. Adverse Reaction Lamivudine 150 mg Twice Daily plus RETROVIR (n = 251) RETROVIR a (n = 230) Body as a Whole Headache 35% 27% Malaise & fatigue 27% 23% Fever or chills 10% 12% Digestive Nausea 33% 29% Diarrhea 18% 22% Nausea & vomiting 13% 12% Anorexia and/or decreased appetite 10% 7% Abdominal pain 9% 11% Abdominal cramps 6% 3% Dyspepsia 5% 5% Nervous System Neuropathy 12% 10% Insomnia & other sleep disorders 11% 7% Dizziness 10% 4% Depressive disorders 9% 4% Respiratory Nasal signs & symptoms 20% 11% Cough 18% 13% Skin Skin rashes 9% 6% Musculoskeletal Musculoskeletal pain 12% 10% Myalgia 8% 6% Arthralgia 5% 5% Pancreatitis: Pancreatitis was observed in 9 out of 2,613 adult subjects (0.3%) who received lamivudine in controlled clinical trials EPV20001, NUCA3001, NUCB3001, NUCA3002, NUCB3002, and NUCB3007 [see Warnings and Precautions (5.4) ]. Lamivudine 300 mg Once Daily: The types and frequencies of clinical adverse reactions reported in subjects receiving lamivudine 300 mg once daily or lamivudine 150 mg twice daily (in 3-drug combination regimens in EPV20001 and EPV40001) for 48 weeks were similar. Selected laboratory abnormalities observed during therapy are summarized in Table 4. Table 4. Frequencies of Selected Grade 3 to 4 Laboratory Abnormalities in Adults in Four 24-Week Surrogate Endpoint Trials (NUCA3001, NUCA3002, NUCB3001, NUCB3002) and a Clinical Endpoint Trial (NUCB3007) a The median duration on study was 12 months. b Either zidovudine monotherapy or zidovudine in combination with zalcitabine. c Current therapy was either zidovudine, zidovudine plus didanosine, or zidovudine plus zalcitabine. ULN = Upper limit of normal. ND = Not done. Test (Threshold Level) 24-Week Surrogate Endpoint Trials a Clinical Endpoint Trial a Lamivudine plus RETROVIR RETROVIR b Lamivudine plus Current Therapy c Placebo plus Current Therapy c Absolute neutrophil count (5.0 x ULN) 3.7% 3.6% 3.8% 1.9% AST (>5.0 x ULN) 1.7% 1.8% 4.0% 2.1% Bilirubin (>2.5 x ULN) 0.8% 0.4% ND ND Amylase (>2.0 x ULN) 4.2% 1.5% 2.2% 1.1% The frequencies of selected laboratory abnormalities re …

7 DRUG INTERACTIONS Sorbitol: Coadministration of lamivudine and sorbitol may decrease lamivudine concentrations; when possible, avoid chronic coadministration. ( 7.2 ) 7.1 Drugs Inhibiting Organic Cation Transporters Lamivudine is predominantly eliminated in the urine by active organic cationic secretion. The possibility of interactions with other drugs administered concurrently should be considered, particularly when their main route of elimination is active renal secretion via the organic cationic transport system (e.g., trimethoprim) [see Clinical Pharmacology (12.3) ] . No data are available regarding interactions with other drugs that have renal clearance mechanisms similar to that of lamivudine. 7.2 Sorbitol Coadministration of single doses of lamivudine and sorbitol resulted in a sorbitol dose-dependent reduction in lamivudine exposures. When possible, avoid use of sorbitol-containing medicines with lamivudine [see Warnings and Precautions (5.5) , Clinical Pharmacology (12.3) ].

8 USE IN SPECIFIC POPULATIONS Lactation: Women infected with HIV should be instructed not to breastfeed due to potential for HIV transmission . (8.2) 8.1 Pregnancy Pregnancy Exposure Registry There is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to lamivudine 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 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 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 (C max ) 35 times the recommended clinical dose (see Data) . Data Human Data: 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 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% to 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: 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 system 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 …

12.1 Mechanism of Action Lamivudine is an antiretroviral agent [see Microbiology (12.4) ] .

11 DESCRIPTION Lamivudine (also known as 3TC) is a synthetic nucleoside analogue with activity against HIV-1 and HBV. The chemical name of lamivudine is (2R,cis)-4-amino-1-(2-hydroxymethyl-1,3-oxathiolan-5-yl)-(1H)-pyrimidin-2-one. Lamivudine is the (-)enantiomer of a dideoxy analogue of cytidine. Lamivudine has also been referred to as (-)2′,3′-dideoxy, 3′-thiacytidine. It has a molecular formula of C 8 H 11 N 3 O 3 S and a molecular weight of 229.3 g per mol. It has the following structural formula: Lamivudine is a white to off-white crystalline solid with a solubility of approximately 70 mg per mL in water at 20°C. Lamivudine Oral Solution, USP is for oral administration. One milliliter (1 mL) of lamivudine oral solution, USP contains 10 mg of lamivudine (10 mg per mL) in an aqueous solution and the inactive ingredients alcohol (5% v/v), edetate disodium, artificial strawberry flavor, citric acid (anhydrous), methylparaben, propylene glycol, propylparaben, sodium citrate (dihydrate), sucrose (200 mg) and purified water. image description

10 OVERDOSAGE There is no known specific treatment for overdose with lamivudine. If overdose occurs, the patient should be monitored and standard supportive treatment applied as required. Because a negligible amount of lamivudine was removed via (4-hour) hemodialysis, continuous ambulatory peritoneal dialysis, and automated peritoneal dialysis, it is not known if continuous hemodialysis would provide clinical benefit in a lamivudine overdose event.

16 HOW SUPPLIED/STORAGE AND HANDLING Lamivudine Oral Solution, USP is a clear, colorless to pale yellow, strawberry flavored liquid. Each mL of the solution contains 10 mg of lamivudine. Packaged as follows: Plastic bottle of 240 mL (NDC 62135-706-37) with child-resistant closure. Unit-Dose cup 30 mL NDC 62135-706-30 20 Unit-Dose Cups of 30 mL each NDC 62135-706-24. This product does not require reconstitution. Recommended Storage: Store bottle at 20° to 25°C (68° to 77°F); excursions permitted to 15° to 30°C (59° to 86°F) [See USP Controlled Room Temperature]. Dispense in a tight, light-resistant container, as defined in the USP.