Emtriva Drug Information

® is indicated in combination with other antiretroviral agents for the treatment of HIV-1 infection. EMTRIVA, a nucleoside analog HIV-1 reverse transcriptase inhibitor, is indicated in combination with other antiretroviral agents for the treatment of HIV-1 infection.

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 EMTRIVA 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 EMTRIVA 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 EMTRIVA and control treatment groups except for skin discoloration, which was reported with higher frequency in the EMTRIVA-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 EMTRIVA 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 EMTRIVA-Treated Subjects in Either Trial 301A or 303 (0–48 Weeks) 303 301A EMTRIVA + AZT/d4T + NNRTI/PI (N=294) 3TC + AZT/d4T + NNRTI/PI (N=146) EMTRIVA + didanosine + EFV (N=286) d4T + didanosine + EFV (N=285) AZT=zidovudine; d4T=stavudine; NNRTI/PI=non-nucleoside reverse transcriptase inhibitor/protease inhibitor; 3TC=lamivudine; EFV=efavirenz.

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 Rash event includes rash, pruritus, maculopapular rash, urticaria, vesiculobullous rash, pustular rash, and allergic reaction. 17% 14% 30% 33% Laboratory Abnormalities : Laboratory abnormalities in these trials occurred with similar frequency in the EMTRIVA and comparator groups. A summary of Grades 3−4 laboratory abnormalities is provided in Table 3. Table 3 Treatment-Emergent Grades 3–4 Laboratory Abnormalities Reported in ≥1% of EMTRIVA-Treated Subjects in Either Trial 301A or 303 303 301A EMTRIVA + AZT/d4T + NNRTI/PI (N=294) 3TC + AZT/d4T + NNRTI/PI (N=146) EMTRIVA + Didanosine + EFV (N=286) d4T + Didanosine + EFV (N=285) Any ≥ Grade 3 Laboratory Abnormality 31% 28% 34% 38% ALT (>5.0 × ULN ULN = Upper limit of normal ) 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 EMTRIVA + 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 2−4) occurring in greater than or equal to 5% of subjects treated in any treatment group. Table 4 Selected Adverse Reactions Frequencies of adverse reactions are based on all treatment-emergent adverse events, regardless of relationship to study drug. (Grades 2–4) Reported in ≥5% in Any Treatment Group in Trial 934 (0–144 Weeks) EMTRIVA + TDF + EFV From Weeks 96 to 144 of the trial, subjects received TRUVADA ® with EFV in place of EMTRIVA + TDF with EFV. 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 Rash event includes rash, exfoliative rash, rash generalized, rash macular, rash maculo-papular, rash pruritic, and rash vesicular. 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 (0–144 Weeks) EMTRIVA + TDF + EFV From Weeks 96 to 144 of the trial, subjects received TRUVADA with EFV in place of EMTRIVA + TDF with EFV. 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 EMTRIVA in adult subjects . 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 3−4 laboratory abnormalities were experienced by 9% of pediatric subjects, including elevated amylase (>2.0 × ULN) (n=4), decreased neutrophils (<750/mm 3 ) (n=3), elevated ALT (>5 × ULN) (n=2), elevated CPK (>4 × ULN) (n=2) and one subject each with elevated bilirubin (>3.0 × ULN), elevated GGT (>10 × ULN), elevated lipase (>2.5 × ULN), decreased hemoglobin (<7 g/dL), and decreased glucose (<40 mg/dL).

The potential for drug interactions with EMTRIVA 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.

Pregnancy Pregnancy Exposure Registry There is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to EMTRIVA 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 increase in the overall risk of major birth defects with first trimester exposure for emtricitabine (FTC) (2.3%) compared with the background rate for major birth defects of 2.7% in a U.S. reference population of the Metropolitan Atlanta Congenital Defects Program (MACDP) (see Data ). The rate of miscarriage for individual drugs is not reported in the APR. In the U.S. general population, the estimated background risk of miscarriage in clinically recognized pregnancies is 15–20%. In animal reproduction studies, no adverse developmental effects were observed when FTC was administered at exposures ≥60 times that of the recommended daily dose of EMTRIVA (see Data ). Data Human Data Based on prospective reports to the APR of exposures to FTC-containing regimens during pregnancy resulting in live births (including over 2,700 exposed in the first trimester and over 1,200 exposed in the second/third trimester), there was no increase between FTC and overall birth defects compared with the background birth defect rate of 2.7% in a U.S. reference population of the MACDP. The prevalence of birth defects in live births was 2.4% (95% CI: 1.9% to 3.1%) with first trimester exposure to FTC-containing regimens and 2.3% (95% CI: 1.5% to 3.3%) with the second/third trimester exposure to FTC-containing regimens. Prospective reports from the APR of overall major birth defects in pregnancies exposed to FTC are compared with a U.S. background major birth defect rate.

Methodologic limitations of the APR include the use of MACDP as the external comparator group. Limitations of using an external comparator include differences in methodology and populations, as well as confounding due to the underlying disease. Additionally, published observational studies on FTC exposure in pregnancy have not shown an increased risk for major malformations.

Animal Data FTC was administered orally to pregnant mice (at 0, 250, 500, or 1,000 mg/kg/day), and rabbits (at 0, 100, 300, or 1,000 mg/kg/day) through organogenesis (on gestation days 6 through 15, and 7 through 19, respectively). No significant toxicological effects were observed in embryo-fetal toxicity studies performed with FTC in mice at exposures (AUC) approximately 60 times higher and in rabbits at approximately 120 times higher than human exposures at the recommended daily dose. In a pre/postnatal development study in mice, FTC was administered orally at doses up to 1,000 mg/kg/day; no significant adverse effects directly related to drug were observed in the offspring exposed daily from before birth (in utero) through sexual maturity at daily exposures (AUC) of approximately 60 times higher than human exposures at the recommended daily dose.

Pediatric Use The safety and efficacy of FTC in patients between 3 months and 21 years of age is supported by data from three open-label, nonrandomized clinical trials in which FTC was administered to 169 HIV-1 infected treatment-naïve and experienced (defined as virologically suppressed on a 3TC containing regimen for which FTC was substituted for 3TC) subjects . The pharmacokinetics of FTC were studied in 20 neonates born to HIV-1 positive mothers . All neonates were HIV-1 negative at the end of the trial; the efficacy of FTC in preventing or treating HIV-1 could not be determined.

is contraindicated in patients with previously demonstrated hypersensitivity to any of the components of the products. EMTRIVA is contraindicated in patients with previously demonstrated hypersensitivity to any of the components of the products.

If overdose occurs, the patient should be monitored for evidence of toxicity, and standard supportive treatment applied as necessary. Hemodialysis treatment removes approximately 30% of the FTC dose over a 3-hour dialysis period starting within 1.5 hours of FTC dosing (blood flow rate of 400 mL/min and a dialysate flow rate of 600 mL/min). It is not known whether FTC can be removed by peritoneal dialysis.