Tenofovir Disoproxil Fumarate

VIREAD is a nucleotide analog HIV-1 reverse transcriptase inhibitor and an HBV reverse transcriptase inhibitor and is indicated: in combination with other antiretroviral agents for the treatment of HIV-1 infection in adults and pediatric patients 2 years of age and older weighing at least 10 kg. ( 1.1 ) for the treatment of chronic hepatitis B in adults and pediatric patients 2 years and older weighing at least 10 kg. ( 1.2 ) 1.1 HIV-1 Infection VIREAD is indicated in combination with other antiretroviral agents for the treatment of human immunodeficiency virus type 1 (HIV-1) infection in adults and pediatric patients 2 years of age and older weighing at least 10 kg.

1.2 Chronic Hepatitis B VIREAD is indicated for the treatment of chronic hepatitis B virus (HBV) in adults and pediatric patients 2 years of age and older weighing at least 10 kg .

VIREAD is available as tablets in four dose strengths or as an oral powder. 150 mg Tablets: 150 mg of tenofovir disoproxil fumarate (TDF) (equivalent to 123 mg of tenofovir disoproxil): triangle shaped, white, film coated, debossed with "GSI" on one side and with "150" on the other side. 200 mg Tablets: 200 mg of TDF (equivalent to 163 mg of tenofovir disoproxil): round shaped, white, film coated, debossed with "GSI" on one side and with "200" on the other side. 250 mg Tablets: 250 mg of TDF (equivalent to 204 mg of tenofovir disoproxil): capsule shaped, white, film coated, debossed with "GSI" on one side and with "250" on the other side. 300 mg Tablets: 300 mg of TDF (equivalent to 245 mg of tenofovir disoproxil): almond shaped, light blue, film coated, debossed with "GILEAD" and "4331" on one side and with "300" on the other side. Oral Powder: white, taste-masked, coated granules containing 40 mg of TDF (equivalent to 33 mg of tenofovir disoproxil) per level scoop. Each level scoop contains 1 gram of oral powder. Tablets: 150 mg, 200 mg, 250 mg, and 300 mg of tenofovir disoproxil fumarate. ( 3 ) Oral Powder: 40 mg per 1 g of oral powder of tenofovir disoproxil fumarate. ( 3 )

None. None. ( 4 )

New onset or worsening renal impairment: Can include acute renal failure and Fanconi syndrome. Avoid administering VIREAD with concurrent or recent use of nephrotoxic drugs. ( 5.2 ) HIV testing: HIV antibody testing should be offered to all HBV-infected patients before initiating therapy with VIREAD. VIREAD should only be used as part of an appropriate antiretroviral combination regimen in HIV-infected patients with or without HBV coinfection. ( 5.3 ) Immune reconstitution syndrome: May necessitate further evaluation and treatment. ( 5.4 ) Decreases in bone mineral density (BMD): Consider assessment of BMD in patients with a history of pathologic fracture or other risk factors for osteoporosis or bone loss. ( 5.5 ) Lactic acidosis/severe hepatomegaly with steatosis: Discontinue treatment in patients who develop symptoms or laboratory findings suggestive of lactic acidosis or pronounced hepatotoxicity. ( 5.6 )

5.1 Severe Acute Exacerbation of Hepatitis B in Patients with HBV Infection All patients should be tested for the presence of chronic hepatitis B virus (HBV) before or when initiating VIREAD [see Dosage and Administration (2.1) ] . Discontinuation of anti-HBV therapy, including VIREAD, may be associated with severe acute exacerbations of hepatitis B. Patients infected with HBV who discontinue VIREAD should be closely monitored with both clinical and laboratory follow-up for at least several months after stopping treatment. If appropriate, resumption of anti-hepatitis B therapy may be warranted, especially in patients with advanced liver disease or cirrhosis, since posttreatment exacerbation of hepatitis may lead to hepatic decompensation and liver failure.

5.2 New Onset or Worsening Renal Impairment Tenofovir is principally eliminated by the kidney. Renal impairment, including cases of acute renal failure and Fanconi syndrome (renal tubular injury with severe hypophosphatemia), has been reported with the use of VIREAD [see Adverse Reactions (6.2) ] . Prior to initiation and during use of VIREAD, on a clinically appropriate schedule, assess serum creatinine, estimated creatinine clearance, urine glucose, and urine protein in all patients. In patients with chronic kidney disease, also assess serum phosphorus. Dosing interval adjustment of VIREAD and close monitoring of renal function are recommended in all patients with creatinine clearance below 50 mL/min [see Dosage and Administration (2.4) ] . No safety or efficacy data are available in patients with renal impairment who received VIREAD using these dosing guidelines, so the potential benefit of VIREAD therapy should be assessed against the potential risk of renal toxicity. VIREAD should be avoided with concurrent or recent use of a nephrotoxic agent (e.g., high-dose or multiple non-steroidal anti-inflammatory drugs [NSAIDs]) [see Drug Interactions (7.1) ] . Cases of acute renal failure after initiation of high-dose or multiple NSAIDs have been reported in HIV-infected patients with risk factors for renal dysfunction who appeared stable on TDF. Some patients required hospitalization and renal replacement therapy. Alternatives to NSAIDs should be considered, if needed, in patients at risk for renal dysfunction. Persistent or worsening bone pain, pain in extremities, fractures and/or muscular pain or weakness may be manifestations of proximal renal tubulopathy and should prompt an evaluation of renal function in patients at risk of renal dysfunction.

5.3 Patients Coinfected with HIV-1 and HBV Due to the risk of development of HIV-1 resistance, VIREAD should only be used in HIV-1 and HBV coinfected patients as part of an appropriate antiretroviral combination regimen. HIV-1 antibody testing should be offered to all HBV-infected patients before initiating therapy with VIREAD. It is also recommended that all patients with HIV-1 be tested for the presence of chronic hepatitis B before initiating treatment with VIREAD.

5.4 Immune Reconstitution Syndrome Immune reconstitution syndrome has been reported in HIV-1 infected patients treated with combination antiretroviral therapy, including VIREAD. During the initial phase of combination antiretroviral treatment, HIV-1 infected patients whose immune system responds may develop an inflammatory response to indolent or residual opportunistic infections (such as Mycobacterium avium infection, cytomegalovirus, Pneumocystis jirovecii pneumonia [PCP], or tuberculosis), which may necessitate further evaluation and treatment. Autoimmune disorders (such as Graves' disease, polymyositis, and Guillain-Barré syndrome) have also been reported to occur in the setting of immune reconstitution; however, the time to onset is more variable, and can occur many months after initiation of treatment.

5.5 Bone Loss and Mineralization Defects Bone Mineral Density In clinical trials in HIV-1 infected adults, VIREAD was associated with slightly greater decreases in bone mineral density (BMD) and increases in biochemical markers of bone metabolism, suggesting increased bone turnover relative to comparators [see Adverse Reactions (6.1) ] . Serum parathyroid hormone levels and 1,25 Vitamin D levels were also higher in subjects receiving VIREAD. Clinical trials evaluating VIREAD in pediatric subjects were conducted. Under normal circumstances, BMD increases rapidly in pediatric patients. In HIV-1 infected subjects 2 years to less than 18 years of age, bone effects were similar to those observed in adult subjects and suggest increased bone turnover. Total body BMD gain was less in the VIREAD-treated HIV-1 infected pediatric subjects as compared to the control groups. Similar trends were observed in chronic HBV-infected pediatric subjects 2 years to less than 18 years of age. In all pediatric trials, normal skeletal growth (height) was not affected for the duration of the clinical trials [see Adverse Reactions (6.1) ] . The effects of VIREAD-associated changes in BMD and biochemical markers on long-term bone health and future fracture risk in adults and pediatric subjects 2 years and older are unknown. The long-term effect of lower spine and total body BMD on skeletal growth in pediatric patients, and in particular, the effects of long-duration exposure in younger children is unknown. Although the effect of supplementation with calcium and vitamin D was not studied, such supplementation may be beneficial. Assessment of BMD should be considered for adult and pediatric patients who have a history of pathologic bone fracture or other risk factors for osteoporosis or bone loss. If bone abnormalities are suspected, appropriate consultation should be obtained. Mineralization Defects Cases of osteomalacia associated with proximal renal tubulopathy, manifested as bone pain or pain in extremities and which may contribute to fractures, have been reported in association with VIREAD use [see Adverse Reactions (6.2) ] . Arthralgia and muscle pain or weakness have also been reported in cases of proximal renal tubulopathy. Hypophosphatemia and osteomalacia secondary to proximal renal tubulopathy should be considered in patients at risk of renal dysfunction who present with persistent or worsening bone or muscle symptoms while receiving TDF-containing products [see Warnings and Precautions (5.2) ].

5.6 Lactic Acidosis/Severe Hepatomegaly with Steatosis Lactic acidosis and severe hepatomegaly with steatosis, including fatal cases, have been reported with the use of nucleoside analogs, including TDF, alone or in combination with other antiretrovirals. Treatment with VIREAD should be suspended in any patient who develops clinical or laboratory findings suggestive of lactic acidosis or pronounced hepatotoxicity (which may include hepatomegaly and steatosis even in the absence of marked transaminase elevations). […]

The following adverse reactions are discussed in other sections of the labeling: Severe Acute Exacerbation of Hepatitis B in Patients with HBV Infection [see Warnings and Precautions (5.1) ] . New Onset or Worsening Renal Impairment [see Warnings and Precautions (5.2) ] . Immune Reconstitution Syndrome [see Warnings and Precautions (5.4) ] . Bone Loss and Mineralization Defects [see Warnings and Precautions (5.5) ] . Lactic Acidosis/Severe Hepatomegaly with Steatosis [see Warnings and Precautions (5.6) ] . In HIV-infected adult subjects: Most common adverse reactions (incidence greater than or equal to 10%, Grades 2–4) were rash, diarrhea, nausea, headache, pain, depression, and asthenia. ( 6.1 ) In HBV-infected subjects with compensated liver disease: Most common adverse reaction (all grades) was nausea (9%). ( 6.1 ) In HBV-infected subjects with decompensated liver disease: Most common adverse reactions (incidence greater than or equal to 10%, all grades) were abdominal pain, nausea, insomnia, pruritus, vomiting, dizziness, and pyrexia. ( 6.1 ) In pediatric subjects: Adverse reactions in pediatric subjects were consistent with those observed in adults. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Gilead Sciences, Inc. at 1-800-GILEAD-5 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 HIV-1 Infected Adults More than 12,000 subjects have been treated with VIREAD alone or in combination with other antiretroviral medicinal products for periods of 28 days to 215 weeks in clinical trials and expanded access programs. A total of 1,544 subjects have received VIREAD 300 mg once daily in clinical trials; over 11,000 subjects have received VIREAD in expanded access programs. The most common adverse reactions (incidence greater than or equal to 10%, Grades 2–4) identified from any of the 3 large controlled clinical trials include rash, diarrhea, headache, pain, depression, asthenia, and nausea. Clinical Trials in Treatment-Naïve HIV-1 Infected Adult Subjects In Trial 903, 600 antiretroviral-naïve subjects received VIREAD (N=299) or stavudine (d4T) (N=301) administered in combination with lamivudine (3TC) and efavirenz (EFV) for 144 weeks. The most common adverse reactions were mild to moderate gastrointestinal events and dizziness. Mild adverse reactions (Grade 1) were common with a similar incidence in both arms and included dizziness, diarrhea, and nausea. 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 903 (0–144 Weeks) VIREAD+3TC+EFV d4T+3TC+EFV N=299 N=301 Rash event Rash event includes rash, pruritus, maculopapular rash, urticaria, vesiculobullous rash, and pustular rash. 18% 12% Headache 14% 17% Pain 13% 12% Diarrhea 11% 13% Depression 11% 10% Back pain 9% 8% Nausea 8% 9% Fever 8% 7% Abdominal pain 7% 12% Asthenia 6% 7% Anxiety 6% 6% Vomiting 5% 9% Insomnia 5% 8% Arthralgia 5% 7% Pneumonia 5% 5% Dyspepsia 4% 5% Dizziness 3% 6% Myalgia 3% 5% Lipodystrophy Lipodystrophy represents a variety of investigator-described adverse events not a protocol-defined syndrome. 1% 8% Peripheral neuropathy Peripheral neuropathy includes peripheral neuritis and neuropathy. 1% 5% Laboratory Abnormalities: Table 5 provides a list of laboratory abnormalities (Grades 3–4) observed in Trial 903. With the exception of fasting cholesterol and fasting triglyceride elevations that were more common in the d4T group (40% and 9%) compared with the VIREAD group (19% and 1%), respectively, laboratory abnormalities observed in this trial occurred with similar frequency in the VIREAD and d4T treatment arms. Table 5 Grades 3–4 Laboratory Abnormalities Reported in ≥1% of VIREAD-Treated Subjects in Trial 903 (0–144 Weeks) VIREAD+3TC+EFV d4T+3TC+EFV N=299 N=301 Any ≥ Grade 3 Laboratory Abnormality 36% 42% Fasting Cholesterol (>240 mg/dL) 19% 40% Creatine Kinase (M: >990 U/L; F: >845 U/L) 12% 12% Serum Amylase (>175 U/L) 9% 8% AST (M: >180 U/L; F: >170 U/L) 5% 7% ALT (M: >215 U/L; F: >170 U/L) 4% 5% Hematuria (>100 RBC/HPF) 7% 7% Neutrophils (<750/mm 3 ) 3% 1% Fasting Triglycerides (>750 mg/dL) 1% 9% Changes in Bone Mineral Density: In HIV-1 infected adult subjects in Trial 903, there was a significantly greater mean percentage decrease from baseline in BMD at the lumbar spine in subjects receiving VIREAD + 3TC + EFV (−2.2% ± 3.9) compared with subjects receiving d4T + 3TC + EFV (−1.0% ± 4.6) through 144 weeks. Changes in BMD at the hip were similar between the two treatment groups (−2.8% ± 3.5 in the VIREAD group vs. −2.4% ± 4.5 in the d4T group). In both groups, the majority of the reduction in BMD occurred in the first 24–48 weeks of the trial and this reduction was sustained through Week 144. Twenty-eight percent of VIREAD-treated subjects vs. 21% of d4T-treated subjects lost at least 5% of BMD at the spine or 7% of BMD at the hip. Clinically relevant fractures (excluding fingers and toes) were reported in 4 subjects in the VIREAD group and 6 subjects in the d4T group. In addition, there were significant increases in biochemical markers of bone metabolism (serum bone-specific alkaline phosphatase, serum osteocalcin, serum C telopeptide, and urinary N telopeptide) and higher serum parathyroid hormone levels and 1,25 Vitamin D levels in the VIREAD group relative to the d4T group; however, except for bone-specific alkaline phosphatase, these changes resulted in values that remained within the normal range [see Warnings and Precautions (5.5) ] . In Trial 934, 511 antiretroviral-naïve subjects received efavirenz (EFV) administered in combination with either emtricitabine (FTC) + VIREAD (N=257) or zidovudine (AZT)/lamivudine (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 6 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 6 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) VIREAD From Weeks 96 to 144 of the trial, subjects received TRUVADA ® with EFV in place of VIREAD + FTC with EFV. +FTC+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 maculopapular, 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 this trial were generally consistent with those seen in previous trials (Table 7). Table 7 Significant Laboratory Abnormalities Reported in ≥1% of Subjects in Any Treatment Group in Trial 934 (0–144 Weeks) VIREAD+FTC+EFV From Weeks 96 to 144 of the trial, subjects received TRUVADA with EFV in place of VIREAD + FTC with EFV. […]

Tenofovir disoproxil fumarate increases didanosine concentrations. Dose reduction and close monitoring for didanosine toxicity are warranted. ( 7.2 ) Coadministration decreases atazanavir concentrations. When coadministered with VIREAD, use atazanavir given with ritonavir. ( 7.2 ) Coadministration of VIREAD with certain HIV-1 protease inhibitors or certain drugs to treat HCV increases tenofovir concentrations. Monitor for evidence of tenofovir toxicity. ( 7.2 ) Consult Full Prescribing Information prior to and during treatment for important drug interactions. ( 7.2 )

7.1 Drugs Affecting Renal Function Tenofovir is primarily eliminated by the kidneys [see Clinical Pharmacology (12.3) ]. Coadministration of VIREAD with drugs that are eliminated by active tubular secretion may increase concentrations of tenofovir and/or the coadministered drug. Some examples include, but are not limited to, acyclovir, cidofovir, ganciclovir, valacyclovir, valganciclovir, aminoglycosides (e.g., gentamicin), and high-dose or multiple NSAIDs [see Warnings and Precautions (5.2) ]. Drugs that decrease renal function may increase concentrations of tenofovir. In the treatment of chronic hepatitis B, VIREAD should not be administered in combination with HEPSERA (adefovir dipivoxil).

7.2 Established and Significant Interactions Table 12 provides a listing of established or clinically significant drug interactions. The drug interactions described are based on studies conducted with TDF [see Clinical Pharmacology (12.3) ]. Table 12 Established and Significant This table is not all inclusive. Drug Interactions: Alteration in Dose or Regimen May Be Recommended Based on Drug Interaction Trials Concomitant Drug Class: Drug Name Effect on Concentration ↑=Increase, ↓=Decrease Clinical Comment NRTI: didanosine ↑ didanosine Patients receiving VIREAD and didanosine should be monitored closely for didanosine-associated adverse reactions. Discontinue didanosine in patients who develop didanosine-associated adverse reactions. Higher didanosine concentrations could potentiate didanosine-associated adverse reactions, including pancreatitis, and neuropathy. Suppression of CD4+ cell counts has been observed in patients receiving VIREAD with didanosine 400 mg daily. In patients weighing greater than 60 kg, reduce the didanosine dose to 250 mg when it is coadministered with VIREAD. In patients weighing less than 60 kg, reduce the didanosine dose to 200 mg when it is coadministered with VIREAD. When coadministered, VIREAD and Videx EC may be taken under fasted conditions or with a light meal (less than 400 kcal, 20% fat). HIV-1 Protease Inhibitor s: atazanavir ↓ atazanavir When coadministered with VIREAD, atazanavir 300 mg should be given with ritonavir 100 mg. lopinavir/ritonavir atazanavir/ritonavir darunavir/ritonavir ↑ tenofovir Monitor patients receiving VIREAD concomitantly with lopinavir/ritonavir, ritonavir-boosted atazanavir, or ritonavir-boosted darunavir for TDF-associated adverse reactions. Discontinue VIREAD in patients who develop TDF-associated adverse reactions. Hepatitis C Antiviral Agents: sofosbuvir/velpatasvir sofosbuvir/velpatasvir/voxilaprevir ↑ tenofovir Monitor patients receiving VIREAD concomitantly with EPCLUSA ® (sofosbuvir/velpatasvir) for adverse reactions associated with TDF. ledipasvir/sofosbuvir Monitor patients receiving VIREAD concomitantly with HARVONI ® (ledipasvir/sofosbuvir) without an HIV-1 protease inhibitor/ritonavir or an HIV-1 protease inhibitor/cobicistat combination, for adverse reactions associated with TDF. In patients receiving VIREAD concomitantly with HARVONI and an HIV-1 protease inhibitor/ritonavir or an HIV-1 protease inhibitor/cobicistat combination, consider an alternative HCV or antiretroviral therapy, as the safety of increased tenofovir concentrations in this setting has not been established. If coadministration is necessary, monitor for adverse reactions associated with TDF.

Lactation: Breastfeeding in HIV-1 infected mothers is not recommended due to the potential for HIV-1 transmission. ( 8.2 )

8.1 Pregnancy Pregnancy Exposure Registry There is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to VIREAD 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 tenofovir disoproxil fumarate (TDF) (2.1%) 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%. Published studies in HBV-infected subjects do not report an increased risk of adverse pregnancy-related outcomes with the use of VIREAD during the third trimester of pregnancy (see Data ) . In animal reproduction studies, no adverse developmental effects were observed when TDF was administered at doses/exposures ≥ 14 (TDF) and 2.7 (tenofovir) times those of the recommended daily dose of VIREAD (see Data ). Data Human Data Based on prospective reports from the APR exposures to TDF-containing regimens during pregnancy resulting in live births (including 3,342 exposed in the first trimester and 1,475 exposed in the second/third trimester), there was no increase in overall major birth defects with TDF compared with the background birth defect rate of 2.7% in a U.S. reference population of the MACDP. The prevalence of major birth defects in live births was 2.3% (95% CI: 1.8% to 2.8%) with first trimester exposure to TDF-containing regimens, and 2.1% (95% CI: 1.4% to 3.0%) with the second/third trimester exposure to TDF-containing regimens. Prospective reports from the APR of overall major birth defects in pregnancies exposed to TDF are compared with a U.S. background major birth defect rate. Methodological 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. In published data from three controlled clinical trials, a total of 327 pregnant women with chronic HBV infection were administered VIREAD from 28 to 32 weeks gestation through 1 to 2 months postpartum and followed for up to 12 months after delivery. There were no new safety findings in pregnant women compared with the known safety profile of VIREAD in HBV-infected adults. An increased risk of adverse pregnancy-related outcomes was not observed; 2 stillbirths were identified, and there was 1 major birth defect (talipes) and 1 occurrence of multiple congenital abnormalities (not further specified) in VIREAD-exposed infants. Infants were followed for up to 12 months after delivery; there were no clinically relevant drug-related safety findings in infants exposed to VIREAD during late gestation. Animal Data TDF was administered orally to pregnant rats (at 0, 50, 150, or 450 mg/kg/day) and rabbits (at 0, 30, 100, or 300 mg/kg/day) through organogenesis (on gestation days 7 through 17, and 6 through 18, respectively). No significant toxicological effects were observed in embryo-fetal toxicity studies performed with TDF in rats at doses up to 14 times the human dose based on body surface area comparisons and in rabbits at doses up to 19 times the human dose based on body surface area comparisons. In a pre/postnatal development study in rats, TDF was administered orally through lactation at doses up to 600 mg/kg/day; no adverse effects were observed in the offspring at tenofovir exposures of approximately 2.7 times higher than human exposures at the recommended daily dose of VIREAD.

8.2 Lactation Risk Summary Based on published data, tenofovir has been shown to be present in human breast milk (see Data ). It is not known if tenofovir affects milk production or has effects on the breastfed child. Treatment of HIV-1 infection: The Centers for Disease Control and Prevention recommend that HIV-1 infected mothers not breastfeed their infants to avoid risking postnatal transmission of HIV-1. Because of the potential for: (1) HIV transmission (in HIV-negative infants); (2) developing viral resistance (in HIV-positive infants); and (3) adverse reactions in a breastfed infant similar to those seen in adults, instruct mothers not to breastfeed if they are taking VIREAD for the treatment of HIV-1. Treatment of HBV infection: The developmental and health benefits of breastfeeding should be considered along with the mother's clinical need for VIREAD and any potential adverse effects on the breastfed infant from VIREAD or from the underlying maternal condition. Data In a study of 50 HIV-uninfected, breastfeeding women on a tenofovir-containing regimen initiated between 1 and 24 weeks postpartum (median 13 weeks), tenofovir was undetectable in the plasma of most infants after 7 days of treatment in mothers. There were no serious adverse events in mothers or infants.

8.4 Pediatric Use Pediatric Patients 2 Years and Older with HIV-1 Infection The safety and effectiveness of VIREAD in pediatric patients 2 years to less than 18 years of age is supported by data from two randomized trials. Trial 352 was a randomized controlled trial in 92 HIV-1 treatment experienced subjects 2 years to less than 12 years of age who were virologically suppressed on a stavudine- or zidovudine-containing regimen and were randomized to either switch to a VIREAD-containing regimen (N=44) or stay on their original regimen (N=48) for 48 weeks. At Week 48, 89% of subjects in the VIREAD treatment group and 90% of subjects in the d4T or AZT treatment group had HIV-1 RNA concentrations <400 copies/mL. Trial 321 was a placebo-controlled trial in 87 HIV-1 treatment experienced subjects 12 years to less than 18 years of age who were treated with VIREAD (N=45) or placebo (N=42) in combination with an optimized background regimen for 48 weeks. Overall, the trial failed to show a difference in virologic response between the VIREAD and placebo groups. Subgroup analyses suggest the lack of difference in virologic response may be attributable to imbalances between treatment arms in baseline viral susceptibility to VIREAD and OBR [see Adverse Reactions (6.1) and Clinical Studies (14.3) ]. Although changes in HIV-1 RNA in these highly treatment-experienced subjects in Trial 321 were less than anticipated, the pharmacokinetic profile of tenofovir in patients 2 years to less than 18 years of age at the recommended doses was similar to that found to be safe and effective in adult clinical trials [see Clinical Pharmacology (12.3) ] . The effects of VIREAD-associated changes in BMD and biochemical markers on long-term bone health and future fracture risk in HIV-1 pediatric patients 2 years and older are unknown. The long-term effect of lower spine and total body BMD on skeletal growth in pediatric patients 2 years and older, and in particular, the effects of long-duration exposure in younger children is unknown [see Warnings and Precautions (5.5) , Adverse Reactions (6.1) ] . Safety and effectiveness of VIREAD in pediatric patients younger than 2 years of age and weighing less than 10 kg with HIV-1 infection have not been established. Pediatric Patients 2 Years of Age and Older with Chronic Hepatitis B The safety and effectiveness of VIREAD in pediatric patients 2 years to less than 18 years of age is supported by data from two randomized trials (Trial 115 and Trial 144) in which VIREAD was administered to HBV-infected treatment-experienced subjects . […]

Tenofovir disoproxil fumarate is an antiviral drug [see Microbiology (12.4) ].