EMTRICITABINE

Emtricitabine (FTC) is a synthetic nucleoside analog with activity against human immunodeficiency virus type 1 (HIV-1) reverse transcriptase. The chemical name of FTC is 5-fluoro-1-(2 R ,5 S )-[2-(hydroxymethyl)-1,3-oxathiolan-5-yl]cytosine. Emtricitabine is the (-) enantiomer of a thio analog of cytidine, which differs from other cytidine analogs in that it has a fluorine in the 5-position. It has a molecular formula of C 8 H 10 FN 3 O 3 S and a molecular weight of 247.24. It has the following structural formula: Emtricitabine is a white to off-white powder with a solubility of approximately 112 mg/mL in water at 25°C. The partition coefficient (log P) for FTC is −0.43 and the pKa is 2.65. Emtricitabine capsules are for oral administration. Each capsule contains 200 mg of FTC and the inactive ingredients: crospovidone, gelatin, magnesium stearate, microcrystalline cellulose, povidone, sodium lauryl sulphate, titanium dioxide and yellow iron oxide. The capsules are imprinted with edible ink containing black iron oxide, potassium hydroxide, propylene glycol, shellac and strong ammonia solution. Figure1

Emtricitabine capsules are indicated in combination with other antiretroviral agents for the treatment of HIV-1 infection. Emtricitabine, a nucleoside analog HIV-1 reverse transcriptase inhibitor, is indicated in combination with other antiretroviral agents for the treatment of HIV-1 infection. ( 1 )

Testing: Prior to or when initiating emtricitabine capsules test for hepatitis B virus infection. ( 2.1 ) Emtricitabine capsules may be taken without regard to food. ( 2.2 ) Adult Patients (18 years of age and older) ( 2.3 ): One 200 mg capsule administered once daily orally. Pediatric Patients (3 months through 17 years of age) ( 2.5 ): For children weighing more than 33 kg who can swallow an intact capsule, one 200 mg capsule administered once daily orally. Dose interval adjustment in adult patients with renal impairment ( 2.6 ): Formulation Creatinine Clearance (mL/min) ≥50 mL/min 30 to 49 mL/min 15 to 29 mL/min <15 mL/min or on hemodialysis a Capsule (200 mg) 200 mg every 24 hours 200 mg every 48 hours 200 mg every 72 hours 200 mg every 96 hours a. Hemodialysis Patients: If dosing on day of dialysis, give dose after dialysis. 2.1 Testing Prior to Initiation of Treatment with Emtricitabine Capsules Prior to or when initiating emtricitabine capsules, test patients for hepatitis B virus infection [see Warnings and Precautions (5.1) ]. 2.2 Recommended Dosage Emtricitabine capsules are taken by mouth once daily and may be taken without regard to food [see Clinical Pharmacology (12.3) ]. 2.3 Recommended Dosage in Adult Patients (18 years of age and older) One 200 mg capsule administered once daily orally. 2.5 Recommended Dosage in Pediatric Patients (3 months through 17 years of age) For pediatric patients weighing more than 33 kg who can swallow an intact capsule, one 200 mg capsule administered once daily orally. 2.6 Dosage Adjustment in Patients with Renal Impairment Table 1 provides dosage interval adjustment for patients with renal impairment. No dosage adjustment is necessary for patients with mild renal impairment (creatinine clearance 50 to 80 mL/min). The safety and effectiveness of dose adjustment recommendations in patients with moderate to severe renal impairment (creatinine clearance below 50 mL/min) have not been clinically evaluated. Therefore, clinical response to treatment and renal function should be closely monitored in these patients [see Warnings and Precautions (5.4) , Use in Specific Populations (8.6) ]. Table 1 Dose Interval Adjustment for Adult Patients with Altered Creatinine Clearance a. Hemodialysis Patients: If dosing on day of dialysis, give dose after dialysis. Formulation Creatinine Clearance (mL/min) ≥50 mL/min 30 to 49 mL/min 15 to 29 mL/min <15 mL/min or on hemodialysis a Capsule (200 mg) 200 mg every 24 hours 200 mg every 48 hours 200 mg every 72 hours 200 mg every 96 hours There are insufficient data available to make dosage recommendations in pediatric patients with renal impairment.

Emtricitabine capsules are contraindicated in patients with previously demonstrated hypersensitivity to any of the components of the products. Emtricitabine capsules are contraindicated in patients with previously demonstrated hypersensitivity to any of the components of the products. ( 4 )

The following adverse reactions are discussed in other sections of the labeling: Severe Acute Exacerbation of Hepatitis B in Patients Coinfected with HIV-1 and HBV [see Warnings and Precautions (5.1) ] . Immune Reconstitution Syndrome [see Warnings and Precautions (5.2) ] . Lactic Acidosis/Severe Hepatomegaly with Steatosis [see Warnings and Precautions (5.3) ]. Most common adverse reactions (incidence ≥10%) are headache, diarrhea, nausea, fatigue, dizziness, depression, insomnia, abnormal dreams, rash, abdominal pain, asthenia, increased cough, and rhinitis. Skin hyperpigmentation was very common (≥10%) in pediatric patients. ( 6 ) To report SUSPECTED ADVERSE REACTIONS, contact Aurobindo Pharma USA, Inc. at 1-866-850-2876 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience 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 practice. Adverse Reactions from Clinical Trials Experience in Adults More than 2,000 adult subjects with HIV-1 infection have been treated with emtricitabine alone or in combination with other antiretroviral agents for periods of 10 days to 200 weeks in clinical trials. The most common adverse reactions (incidence greater than or equal to 10%, any severity) identified from any of the three large, controlled clinical trials include headache, diarrhea, nausea, fatigue, dizziness, depression, insomnia, abnormal dreams, rash, abdominal pain, asthenia, increased cough, and rhinitis. In Trials 301A and 303, the most common adverse reactions that occurred in subjects receiving emtricitabine with other antiretroviral agents were headache, diarrhea, nausea, and rash, which were generally mild to moderate. Approximately 1% of subjects discontinued participation in the clinical trials due to these events. All adverse reactions were reported with similar frequency in emtricitabine and control treatment groups except for skin discoloration, which was reported with higher frequency in the emtricitabine-treated group. Skin discoloration, manifested by hyperpigmentation on the palms or soles, was generally mild and asymptomatic. The mechanism and clinical significance are unknown. A summary of emtricitabine treatment-emergent clinical adverse reactions in Trials 301A and 303 is provided in Table 2. Table 2 Selected Treatment-Emergent Adverse Reactions (All Grades, Regardless of Causality) Reported in ≥3% of Emtricitabine-Treated Subjects in Either Trial 301A or 303 (0 to 48 Weeks) AZT=zidovudine; d4T=stavudine; NNRTI/PI=non-nucleoside reverse transcriptase inhibitor/protease inhibitor; 3TC=lamivudine; EFV=efavirenz. a. Rash event includes rash, pruritus, maculopapular rash, urticaria, vesiculobullous rash, pustular rash, and allergic reaction. 303 301A Emtricitabine + AZT/d4T + NNRTI/PI (N=294) 3TC + AZT/d4T + NNRTI/PI (N=146) Emtricitabine + didanosine + EFV (N=286) d4 T + didanosine + EFV (N=285) Body as a Whole Asthenia 16% 10% 12% 17% Headache 13% 6% 22% 25% Abdominal pain 8% 11% 14% 17% Digestive System Diarrhea 23% 18% 23% 32% Nausea 18% 12% 13% 23% Vomiting 9% 7% 9% 12% Dyspepsia 4% 5% 8% 12% Musculoskeletal Myalgia 4% 4% 6% 3% Arthralgia 3% 4% 5% 6% Nervous System Insomnia 7% 3% 16% 21% Depressive disorders 6% 10% 9% 13% Paresthesia 5% 7% 6% 12% Dizziness 4% 5% 25% 26% Neuropathy/peripheral neuritis 4% 3% 4% 13% Abnormal dreams 2% <1% 11% 19% Respiratory Rhinitis 18% 12% 12% 10% Increased cough 14% 11% 14% 8% Skin Rash event a 17% 14% 30% 33% Laboratory Abnormalities : Laboratory abnormalities in these trials occurred with similar frequency in the emtricitabine and comparator groups. A summary of Grades 3 to 4 laboratory abnormalities is provided in Table 3. Table 3 Treatment-Emergent Grades 3 to 4 Laboratory Abnormalities Reported in ≥1% of Emtricitabine-Treated Subjects in Either Trial 301A or 303 a. ULN = Upper limit of normal 303 301A Emtricitabine + AZT/d4T + NNRTI/PI (N=294) 3TC + AZT/d4T + NNRTI/PI (N=146) Emtricitabine + Didanosine + EFV (N=286) d4 T + Didanosine + EFV (N=285) Any ≥ Grade 3 Laboratory Abnormality 31% 28% 34% 38% ALT (>5.0 × ULN a ) 2% 1% 5% 6% AST (>5.0 × ULN) 3% <1% 6% 9% Bilirubin (>2.5 × ULN) 1% 2% <1% <1% Creatine kinase (>4.0 × ULN) 11% 14% 12% 11% Neutrophils (<750 mm 3 ) 5% 3% 5% 7% Pancreatic amylase (>2.0 × ULN) 2% 2% <1% 1% Serum amylase (>2.0 × ULN) 2% 2% 5% 10% Serum glucose <40 or >250 mg/dL) 3% 3% 2% 3% Serum lipase (>2.0 × ULN) <1% <1% 1% 2% Triglycerides (>750 mg/dL) 10% 8% 9% 6% In Trial 934, 511 antiretroviral-naïve subjects received efavirenz (EFV) administered in combination with either emtricitabine + tenofovir disoproxil fumarate (TDF) (N=257) or AZT/3TC (N=254) for 144 weeks. The most common adverse reactions (incidence greater than or equal to 10%, all grades) included diarrhea, nausea, fatigue, headache, dizziness, depression, insomnia, abnormal dreams, and rash. Table 4 provides the treatment-emergent adverse reactions (Grades 2 to 4) occurring in greater than or equal to 5% of subjects treated in any treatment group. Table 4 Selected Adverse Reactions a (Grades 2 to 4) Reported in ≥5% in Any Treatment Group in Trial 934 (0 to 144 Weeks) a. Frequencies of adverse reactions are based on all treatment-emergent adverse events, regardless of relationship to study drug. b. From Weeks 96 to 144 of the trial, subjects received TRUVADA ® with EFV in place of emtricitabine + TDF with EFV. c. Rash event includes rash, exfoliative rash, rash generalized, rash macular, rash maculo-papular, rash pruritic, and rash vesicular. Emtricitabine + TDF + EFV b AZT/3TC + EFV N=257 N=254 Fatigue 9% 8% Depression 9% 7% Nausea 9% 7% Diarrhea 9% 5% Dizziness 8% 7% Upper respiratory tract infections 8% 5% Sinusitis 8% 4% Rash event c 7% 9% Headache 6% 5% Insomnia 5% 7% Nasopharyngitis 5% 3% Vomiting 2% 5% Laboratory Abnormalities: Laboratory abnormalities observed in Trial 934 were generally consistent with those seen in previous trials (Table 5). Table 5 Significant Laboratory Abnormalities Reported in ≥1% of Subjects in Any Treatment Group in Trial 934 (0 to 144 Weeks) a. From Weeks 96 to 144 of the trial, subjects received TRUVADA with EFV in place of emtricitabine + TDF with EFV. Emtricitabine + TDF + EFV a AZT/3TC + EFV N=257 N=254 Any ≥ Grade 3 Laboratory Abnormality 30% 26% Fasting Cholesterol (>240 mg/dL) 22% 24% Creatine Kinase (M: >990 U/L) (F: >845 U/L) 9% 7% Serum Amylase (>175 U/L) 8% 4% Alkaline Phosphatase (>550 U/L) 1% 0% AST (M: >180 U/L) (F: >170 U/L) 3% 3% ALT (M: >215 U/L) (F: >170 U/L) 2% 3% Hemoglobin (<8.0 mg/dL) 0% 4% Hyperglycemia (>250 mg/dL) 2% 1% Hematuria (>75 RBC/HPF) 3% 2% Glycosuria (3+) <1% 1% Neutrophils (<750/mm 3 ) 3% 5% Fasting Triglycerides (>750 mg/dL) 4% 2% Adverse Reactions from Clinical Trials Experience in Pediatric Subjects Assessment of adverse reactions in pediatric subjects is based on data from Trial 203, an open label, uncontrolled trial of 116 HIV-1 infected subjects who received FTC through 48 weeks. The adverse reaction profile in pediatric subjects was generally comparable to that observed in clinical trials of emtricitabine in adult subjects [see Adverse Reactions (6.1) ] . Hyperpigmentation was more frequent in children. Additional adverse reactions identified from this trial include anemia. Selected treatment-emergent adverse events, regardless of causality, reported in subjects during 48 weeks of treatment were the following: infection (44%), hyperpigmentation (32%), increased cough (28%), vomiting (23%), otitis media (23%), rash (21%), rhinitis (20%), diarrhea (20%), fever (18%), pneumonia (15%), gastroenteritis (11%), abdominal pain (10%), and anemia (7%). Treatment-emergent Grades 3 to 4 laboratory abnormalities were experienced by 9% of pediatric subjects, including elevated amylase (>2.0 x ULN) (n=4), decreased neutrophils (<750/mm 3 ) (n=3), elevated ALT (>5 x ULN) (n=2), elevated CPK (>4 x ULN) (n=2) and one subject each with elevated bilirubin (>3.0 x ULN), elevated GGT (>10 x ULN), elevated lipase (>2.5 x ULN), decreased hemoglobin (<7 g/dL), and decreased glucose (<40 mg/dL).

The potential for drug interactions with emtricitabine has been studied in combination with AZT, indinavir, d4T, famciclovir, and tenofovir DF (TDF). There were no clinically significant drug interactions for any of these drugs. Drug interactions trials are described elsewhere in the labeling [see Clinical Pharmacology (12.3) ].