Tenofovir Disoproxil Fumarate

1 INDICATIONS & USAGE Tenofovir disoproxil fumarate tablets are a nucleotide analog HIV-1 reverse transcriptase inhibitor and an HBV reverse transcriptase inhibitor. • Tenofovir disoproxil fumarate tablets are 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. (1) • Tenofovir disoproxil fumarate tablets are indicated for the treatment of chronic hepatitis B in adults and pediatric patients 12 years of age and older. (1) 1.1 HIV-1 Infection Tenofovir disoproxil fumarate tablets are 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. The following points should be considered when initiating therapy with tenofovir disoproxil fumarate tablets for the treatment of HIV-1 infection: • Tenofovir disoproxil fumarate tablets should not be used in combination with ATRIPLA ® , BIKTARVY ® , COMPLERA ® , DESCOVY ® , GENVOYA ® , ODEFSEY ® , STRIBILD ® , TRUVADA ® , or VEMLIDY ® [See Warnings and Precautions (5.4)]. 1.2 Chronic Hepatitis B Tenofovir disoproxil fumarate tablets are indicated for the treatment of chronic hepatitis B in adults and pediatric patients 12 years of age and older. The following points should be considered when initiating therapy with tenofovir disoproxil fumarate tablets for the treatment of chronic hepatitis B infection: • The indication in adults is based on safety and efficacy data from treatment of subjects who were nucleoside-treatment-naïve and subjects who were treatment-experienced with documented resistance to lamivudine. Subjects were adults with HBeAg-positive and HBeAg-negative chronic hepatitis B with compensated liver disease [See Clinical Studies (14.2)]. • Tenofovir disoproxil fumarate tablets were evaluated in a limited number of subjects with chronic hepatitis B and decompensated liver disease [See Adverse Reactions (6.1), Clinical Studies (14.2)]. • The numbers of subjects in clinical trials who had adefovir resistance-associated substitutions at baseline were too small to reach conclusions of efficacy [See Microbiology (12.4), Clinical Studies ( 14.2)].

2 DOSAGE & ADMINISTRATION • Recommended dose for the treatment of HIV-1 or chronic hepatitis B in adults and pediatric patients 12 years of age and older (35 kg or more): 300 mg once daily taken orally without regard to food. (2.1) • Recommended dose for the treatment of HIV-1 in pediatric patients (2 to less than 12 years of age): o Tablets: For pediatric patients weighing greater than or equal to 17 kg who can swallow an intact tablet, one tenofovir disoproxil fumarate tablet (300 mg based on body weight) once daily taken orally without regard to food. (2.2) • Dose recommended in renal impairment in adults: o Creatinine clearance 30 to 49 mL/min: 300 mg every 48 hours. (2.3) o Creatinine clearance 10 to 29 mL/min: 300 mg every 72 to 96 hours. (2.3) o Hemodialysis: 300 mg every 7 days or after approximately 12 hours of dialysis. (2.3) 2.1 Recommended Dose in Adults and Pediatric Patients 12 Years of Age and Older (35 kg or more) For the treatment of HIV-1 or chronic hepatitis B: The dose is one 300 mg tenofovir disoproxil fumarate tablet once daily taken orally, without regard to food. In the treatment of chronic hepatitis B, the optimal duration of treatment is unknown. Safety and efficacy in pediatric patients with chronic hepatitis B weighing less than 35 kg have not been established. 2.2 Recommended Dose in Pediatric Patients 2 Years to Less than 12 Years of Age HIV-1 Infection For the treatment of HIV-1 in pediatric patients 2 years of age and older, the recommended oral dose of tenofovir disoproxil fumarate tablet is 8 mg of tenofovir disoproxil fumarate (tenofovir DF) per kilogram of body weight (up to a maximum of 300 mg) once daily administered as tablets. Tenofovir disoproxil fumarate is available as tablets in 300 mg strength for pediatric patients who weigh greater than or equal to 17 kg and who are able to reliably swallow intact tablets. The dose is one tablet once daily taken orally, without regard to food. Table 2 contain dosing recommendations for tenofovir disoproxil fumarate tablets based on body weight. Weight should be monitored periodically and the tenofovir disoproxil fumarate tablets dose adjusted accordingly. Table 2 Dosing Recommendations for Pediatric Patients 2 Years of Age and Older and Weighing At Least 17 kg Using Tenofovir Disoproxil Fumarate Tablets Body Weight Kilogram (kg) Tablets Once Daily 17 to less than 22 150 mg 22 to less than 28 200 mg 28 to less than 35 250 mg 35 or greater 300 mg Chronic Hepatitis B Safety and efficacy of tenofovir disoproxil fumarate tablets in patients younger than 12 years of age have not been established. 2.3 Dose Adjustment for Renal Impairment in Adults Significantly increased drug exposures occurred when tenofovir disoproxil fumarate tablets were administered to subjects with moderate to severe renal impairment [See Clinical Pharmacology (12.3)] . Therefore, the dosing interval of tenofovir disoproxil fumarate tablets 300 mg should be adjusted in patients with baseline creatinine clearance below 50 mL/min using the recommendations in Table 3. These dosing interval recommendations are based on modeling of single-dose pharmacokinetic data in non-HIV and non-HBV infected subjects with varying degrees of renal impairment, including end-stage renal disease requiring hemodialysis. The safety and effectiveness of these dosing interval adjustment recommendations have not been clinically evaluated in patients with moderate or severe renal impairment; therefore, clinical response to treatment and renal function should be closely monitored in these patients [See Warnings and Precautions (5.2)] . No dose adjustment of tenofovir disoproxil fumarate tablets 300 mg is necessary for patients with mild renal impairment (creatinine clearance 50 to 80 mL/min). Routine monitoring of estimated creatinine clearance, serum phosphorus, urine glucose, and urine protein should be performed in patients with mild renal impairment [See Warnings and Precautions (5.2)] . Table 3 Dosage Adjustment for Patients with Altered Creatinine Clearance Cre atinine Clearan ce (mL/min) a Hemodial ysis Patients 50 or greater 30- 49 10- 29 Recomm en ded 300 mg Dosing Inte r v al Every 24 hours Every 48 hours Every 72 to 96 hours Every 7 days or after a tot al of approximate ly 12 hours of dialysis a. Calculated using ideal (lean) body weight. b. Generally once weekly assuming three hemodialysis sessions a week of approximately 4 hours duration. Tenofovir disoproxil fumarate tablets should be administered following completion of dialysis. The pharmacokinetics of tenofovir have not been evaluated in non-hemodialysis patients with creatinine clearance below 10 mL/min; therefore, no dosing recommendation is available for these patients. No data are available to make dose recommendations in pediatric patients with renal impairment.

6 ADVERSE REACTIONS The following adverse reactions are discussed in other sections of the labeling: • Severe Acute Exacerbation of Hepatitis [See Boxed Warning, Warnings and Precautions ( 5.1 )]. • New Onset or Worsening Renal Impairment [See Warnings and Precautions ( 5.2 )]. • Lactic Acidosis/Severe Hepatomegaly with Steatosis [See Warnings and Precautions ( 5.3 )]. • Bone Effects [See Warnings and Precautions ( 5.6 )]. • Immune Reconstitution Syndrome [See Warnings and Precautions ( 5.7)]. • In HIV-infected adult subjects: Most common adverse reactions (incidence greater than or equal to 10%, Grades 2 to 4) are rash, diarrhea, headache, pain, depression, asthenia, and nausea. (6.1) • In HBV-infected subjects with compensated liver disease: Most common adverse reaction (all grades) was nausea (9%). (6.1) • In pediatric subjects: Adverse reactions in pediatric subjects were consistent with those observed in adults. (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) To report SUSPECTED ADVERSE REACTIONS, contact NorthStar Rx LLC at 1-800-206-7821 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch 6.1 Adverse Reactions from 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. Clinical Trials in Adult Patients with HIV-1 Infection More than 12,000 subjects have been treated with tenofovir disoproxil fumarate tablets 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 tenofovir disoproxil fumarate tablets 300 mg once daily in clinical trials; over 11,000 subjects have received tenofovir disoproxil fumarate tablets in expanded access programs. The most common adverse reactions (incidence greater than or equal to 10%, Grades 2 to 4) identified from any of the 3 large controlled clinical trials include rash, diarrhea, headache, pain, depression, asthenia, and nausea. Treatment-Naïve Patients Study 903 - Treatment-Emergent Adverse-Reactions: The most common adverse reactions seen in a double-blind comparative controlled trial in which 600 treatment-naïve subjects received tenofovir disoproxil fumarate tablets (N=299) or stavudine (N=301) in combination with lamivudine and efavirenz for 144 weeks (Study 903) 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. Selected treatment-emergent moderate to severe adverse reactions are summarized in Table 4. Table 4 Selected Treatment-Emergent Adverse Reactionsa (Grades 2 to 4) Reported in ≥5% in Any Treatment Group in Study 903 (0 to 144 Weeks) Tenofovir disoproxil fumarate Tablets +3TC+EFV d4T+3TC+EFV N=299 N=301 Body as a Whole Headache Pain Fever Abdominal pain Back pain Asthenia 14% 13% 8% 7% 9% 6% 17% 12% 7% 12% 8% 7% Digestive System Diarrhea Nausea Dyspepsia Vomiting 11% 8% 4% 5% 13% 9% 5% 9% Metabolic Disorders Lipodystrophy b 1% 8% Musculoskeletal Arthralgia Myalgia 5% 3% 7% 5% Nervous System Depression Insomnia Dizziness Peripheral neuropathy c Anxiety 11% 5% 3% 1% 6% 10% 8% 6% 5% 6% Respiratory Pneumonia 5% 5% Skin and Appendages Rash event d 18% 12% a. Frequencies of adverse reactions are based on all treatment-emergent adverse events, regardless of relationship to study drug. b. Lipodystrophy represents a variety of investigator-described adverse events not a protocol-defined syndrome. c. Peripheral neuropathy includes peripheral neuritis and neuropathy. d. Rash event includes rash, pruritus, maculopapular rash, urticaria, vesiculobullous rash, and pustular rash. Laboratory Abnormalities: With the exception of fasting cholesterol and fasting triglyceride elevations that were more common in the stavudine group (40% and 9%) compared with tenofovir disoproxil fumarate tablets (19% and 1%), respectively, laboratory abnormalities observed in this trial occurred with similar frequency in the tenofovir disoproxil fumarate tablets and stavudine treatment arms. A summary of Grades 3 to 4 laboratory abnormalities is provided in Table 5. Table 5 Grades 3 to 4 Laboratory Abnormalities Reported in ≥1% of Tenofovir Disoproxil Fumarate-Treated Subjects in Study 903 (0 to 144 Weeks) Tenofovir disoproxil fumarate Tablets+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% Study 934 – Treatment-Emergent Adverse Reactions: In Study 934, 511 antiretroviral-naïve subjects received either tenofovir disoproxil fumarate tablets + EMTRIVA ® administered in combination with efavirenz (N=257) or zidovudine/lamivudine administered in combination with efavirenz (N=254). Adverse reactions observed in this trial were generally consistent with those seen in previous studies in treatment-experienced or treatment-naïve subjects (Table 6). Changes in Bone Mineral Density In HIV-1 infected adult subjects in Study 903, there was a significantly greater mean percentage decrease from baseline in BMD at the lumbar spine in subjects receiving tenofovir disoproxil fumarate tablets + lamivudine + efavirenz (-2.2% ± 3.9) compared with subjects receiving stavudine + lamivudine + efavirenz (-1% ± 4.6) through 144 weeks. Changes in BMD at the hip were similar between the two treatment groups (-2.8% ± 3.5 in the tenofovir disoproxil fumarate tablets group vs. -2.4% ± 4.5 in the stavudine group). In both groups, the majority of the reduction in BMD occurred in the first 24 to 48 weeks of the trial and this reduction was sustained through Week 144. Twenty-eight percent of tenofovir disoproxil fumarate tablets-treated subjects vs. 21% of the stavudine-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 tenofovir disoproxil fumarate tablets group and 6 subjects in the stavudine 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 tenofovir disoproxil fumarate tablets group relative to the stavudine group; however, except for bone-specific alkaline phosphatase, these changes resulted in values that remained within the normal range [See Warnings and Precautions (5.6)]. Table 6 Selected Treatment-Emergent Adverse Reactions a (Grades 2 to 4) Reported in ≥5% in Any Treatment Group in Study 934 (0 to 144 Weeks) Tenofovir disoproxil fumarate Tablets b +FTC+EFV AZT/3TC+EFV N=257 N=254 Gastrointestinal Disorder Diarrhea Nausea Vomiting 9% 9% 2% 5% 7% 5% General Disorders and Administration Site Condition Fatigue 9% 8% Infections and Infestations Sinusitis Upper respiratory tract infections Nasopharyngitis 8% 8% 5% 4% 5% 3% Nervous System Disorders Headache Dizziness 6% 8% 5% 7% Psychiatric Disorders Depression Insomnia 9% 5% 7% 7% Skin and Subcutaneous Tissue Disorders Rash event c 7% 9% 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 efavirenz in place of tenofovir disoproxil fumarate tablets + EMTRIVA with efavirenz. c. Rash event includes rash, exfoliative rash, rash generalized, rash macular, rash maculopapular, rash pruritic, and rash vesicular. 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 Study 934 (0 to 144 Weeks) Tenofovir disoproxil fumarate a Tablets+FTC+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 mg/dL) 0% 4% Hyperglycemia (>250 mg/dL) 2% 1% Hematuria (>75 RBC/HPF) 3% 2% Glycosuria (³3+) <1% 1% Neutrophils (<750/mm 3 ) 3% 5% Fasting Triglycerides (>750 mg/dL) 4% 2% a. From Weeks 96 to 144 of the trial, subjects received TRUVADA with efavirenz in place of tenofovir disoproxil fumarate tablets + EMTRIVA with efavirenz. Treatment-Experienced Patients Treatment-Emergent Adverse Reactions: The adverse reactions seen in treatment-experienced subjects were generally consistent with those seen in treatment-naïve subjects including mild to moderate gastrointestinal events, such as nausea, diarrhea, vomiting, and flatulence. Less than 1% of subjects discontinued participation in the clinical trials due to gastrointestinal adverse reactions (Study 907). A summary of moderate to severe treatment-emergent adverse reactions that occurred during the first 48 weeks of Study 907 is provided in Table 8. Table 8 Selected Treatment-Emergent Adverse Reactionsa (Grades 2 to 4) Reported in ≥3% in Any Treatment Group in Study 907 (0 to 48 Weeks) Tenofovir disoproxil fumarate Tablets ( N=3 68) (Week 0 -2 4) Placebo ( N=1 82) (Week 0 -2 4) Tenofovir disoproxil fumarate Tablets ( N=3 68) (Week 0 -4 8) Placebo C rosso ver to T enofovir disoproxil fumarate Tablets ( N=1 70) (Week 2 4 -4 8) Body as a Whole Asthenia Pain He ad a che Abdomi nal p ain Back pain Ch e st pain Fever 7% 7% 5% 4% 3% 3% 2% 6% 7% 5% 3% 3% 1% 2% 11% 12% 8% 7% 4% 3% 4% 1% 4% 2% 6% 2% 2% 2% Dig estive System Diarr hea Na u s ea Vomiting Anorexia Dys pe psia Flatule nce 11% 8% 4% 3% 3% 3% 10% 5% 1% 2% 2% 1% 16% 11% 7% 4% 4% 4% 11% 7% 5% 1% 2% 1% R espiratory Pneum onia 2% 0% 3% 2% Ner vous S ys tem De pr ess ion Insomn ia Perip heral neuropathy b Dizzi ness 4% 3% 3% 1% 3% 2% 3% 3% 8% 4% 5% 3% 4% 4% 2% 1% Skin and A ppend age R ash event c Sweating 5% 3% 4% 2% 7% 3% 1% 1% Musculoskeletal Myalgia 3% 3% 4% 1% Metabol ic Wei ght loss 2% 1% 4% 2% a. Frequencies of adverse reactions are based on all treatment-emergent adverse events, regardless of relationship to study drug. b. Peripheral neuropathy includes peripheral neuritis and neuropathy. c. Rash event includes rash, pruritus, maculopapular rash, urticaria, vesiculobullous rash, and pustular rash. Laboratory Abnormalities: Laboratory abnormalities observed in this trial occurred with similar frequency in the tenofovir disoproxil fumarate tablets and placebo-treated groups. A summary of Grades 3 to 4 laboratory abnormalities is provided in Table 9. Table 9 Grades 3 to 4 Laboratory Abnormalities Reported in ≥1% of Tenofovir Disoproxil Fumarate Tablets-Treated Subjects in Study 907 (0 to 48 Weeks) Tenofovir disoproxil fumarate Tablets ( N=3 68) (Week 0-2 4) Placebo ( N=1 82) (Week 0-2 4) Tenofovir disoproxil fumarate Tablets ( N=3 68) (Week 0-4 8) Placebo Cro sso ver to Tenofovir disoproxil fumarate (N=170) (Week 24-48) Any ≥ Gra de 3 Lab orat ory Abnor mality 25% 38% 35% 34% Triglyceri des (> 750 mg/ dL) 8% 13% 11% 9% Cr eatine Kin ase (M: >9 90 U/ L; F: >845 U/L) 7% 14% 12% 12% Serum Amyl a se (>1 75 U/ L) 6% 7% 7% 6% Glycosuria (≥ 3+) 3% 3% 3% 2% AST (M: >180 U/L; F: >170 U/L) 3% 3% 4% 5% ALT (M: >215 U/L; F: >170 U/L) 2% 2% 4% 5% Serum Gl u c o se (>2 50 U/ L) 2% 4% 3% 3% Neutrophi ls (<7 50/mm 3 ) 1% 1% 2% 1% Clinical Trials in Pediatric Subjects 2 Years of Age and Older with HIV-1 Infection Assessment of adverse reactions is based on two randomized trials (Studies 352 and 321) in 184 HIV-1 infected pediatric subjects (2 to less than 18 years of age) who received treatment with tenofovir disoproxil fumarate tablets (N=93) or placebo/active comparator (N=91) in combination with other antiretroviral agents for 48 weeks. The adverse reactions observed in subjects who received treatment with tenofovir disoproxil fumarate tablets were consistent with those observed in clinical trials in adults. Eighty-nine pediatric subjects (2 to less than 12 years of age) received tenofovir disoproxil fumarate tablets in Study 352 for a median exposure of 104 weeks. Of these, 4 subjects discontinued from the trial due to adverse reactions consistent with proximal renal tubulopathy. Three of these 4 subjects presented with hypophosphatemia and also had decreases in total body or spine BMD Z score [See Warnings and Precautions (5.6)]. Changes in Bone Mineral Density: Clinical trials in HIV-1 infected children and adolescents evaluated BMD changes. In Study 321 (12 to less than 18 years), the mean rate of BMD gain at Week 48 was less in the tenofovir disoproxil fumarate tablets compared to the placebo treatment group. Six tenofovir disoproxil fumarate tablets-treated subjects and one placebo-treated subject had significant (greater than 4%) lumbar spine BMD loss at Week 48. Changes from baseline BMD Z-scores were -0.341 for lumbar spine and -0.458 for total body in the 28 subjects who were treated with tenofovir disoproxil fumarate tablets for 96 weeks. In Study 352 (2 to less than 12 years), the mean rate of BMD gain in lumbar spine at Week 48 was similar between the tenofovir disoproxil fumarate tablets and the d4T or AZT treatment groups. Total body BMD gain was less in the tenofovir disoproxil fumarate tablets compared to the d4T or AZT treatment groups. One tenofovir disoproxil fumarate-treated subject and none of the d4T or AZT-treated subjects experienced significant (greater than 4%) lumbar spine BMD loss at Week 48. Changes from baseline in BMD Z scores were -0.012 for lumbar spine and -0.338 for total body in the 64 subjects who were treated with tenofovir disoproxil fumarate tablets for 96 weeks. In both trials, skeletal growth (height) appeared to be unaffected [See Warnings and Precautions (5.6)]. Clinical Trials in Adult Subjects with Chronic Hepatitis B and Compensated Liver Disease Treatment-Emergent Adverse Reactions: In controlled clinical trials in 641 subjects with chronic hepatitis B (0102 and 0103), more subjects treated with tenofovir disoproxil fumarate tablets during the 48-week double-blind period experienced nausea: 9% with tenofovir disoproxil fumarate tablets versus 2% with HEPSERA. Other treatment-emergent adverse reactions reported in more than 5% of subjects treated with tenofovir disoproxil fumarate tablets included: abdominal pain, diarrhea, headache, dizziness, fatigue, nasopharyngitis, back pain, and skin rash. During the open-label phase of treatment with tenofovir disoproxil fumarate tablets (weeks 48 to 384) in Studies 0102 and 0103, 2% of subjects (13/585) experienced a confirmed increase in serum creatinine of 0.5 mg/dL from baseline. No significant change in the tolerability profile was observed with continued treatment for up to 384 weeks. Laboratory Abnormalities: A summary of Grades 3 to 4 laboratory abnormalities through Week 48 is provided in Table 10. Grades 3 to 4 laboratory abnormalities were similar in subjects continuing tenofovir disoproxil fumarate tablets treatment for up to 384 weeks in these trials. Table 10 Grades 3 to 4 Laboratory Abnormalities Reported in ≥1% of Tenofovir disoproxil fumarate -Treated Subjects in Studies 0102 and 0103 (0 to 48 Weeks) Tenofovir disoproxil fumarate Tablets (N=426) HEPSERA (N=215) Any ≥ Grade 3 Laboratory Abnormality 19% 13% Creatine Kinase (M: >990 U/L; F: >845 U/L) 2% 3% Serum Amylase (>175 U/L) 4% 1% Glycosuria (≥3+) 3% <1% AST (M: >180 U/L; F: >170 U/L) 4% 4% ALT (M: >215 U/L; F: >170 U/L) 10% 6% The overall incidence of on-treatment ALT flares (defined as serum ALT greater than 2 × baseline and greater than 10 × ULN, with or without associated symptoms) was similar between tenofovir disoproxil fumarate tablets (2.6%) and HEPSERA (2%). ALT flares generally occurred within the first 4 to 8 weeks of treatment and were accompanied by decreases in HBV DNA levels. No subject had evidence of decompensation. ALT flares typically resolved within 4 to 8 weeks without changes in study medication. The adverse reactions observed in subjects with chronic hepatitis B and lamivudine resistance who received treatment with tenofovir disoproxil fumarate tablets were consistent with those observed in other hepatitis B clinical trials in adults. Clinical Trials in Adult Subjects with Chronic Hepatitis B and Decompensated Liver Disease In a small randomized, double-blind, active-controlled trial (0108), subjects with CHB and decompensated liver disease received treatment with tenofovir disoproxil fumarate tablets or other antiviral drugs for up to 48 weeks [See Clinical Studies (14.2)]. Among the 45 subjects receiving tenofovir disoproxil fumarate tablets, the most frequently reported treatment-emergent adverse reactions of any severity were abdominal pain (22%), nausea (20%), insomnia (18%), pruritus (16%), vomiting (13%), dizziness (13%), and pyrexia (11%). Two of 45 (4%) subjects died through Week 48 of the trial due to progression of liver disease. Three of 45 (7%) subjects discontinued treatment due to an adverse event. Four of 45 (9%) subjects experienced a confirmed increase in serum creatinine of 0.5 mg/dL (1 subject also had a confirmed serum phosphorus less than 2 mg/dL through Week 48). Three of these subjects (each of whom had a Child-Pugh score greater than or equal to 10 and MELD score greater than or equal to 14 at entry) developed renal failure. Because both tenofovir disoproxil fumarate tablets and decompensated liver disease may have an impact on renal function, the contribution of tenofovir disoproxil fumarate tablets to renal impairment in this population is difficult to ascertain. One of 45 subjects experienced an on-treatment hepatic flare during the 48-Week trial. Clinical Trials in Pediatric Subjects 12 Years of Age and Older with Chronic Hepatitis B Assessment of adverse reactions is based on one randomized study (Study GS-US-174-0115) in 106 pediatric subjects (12 to less than 18 years of age) infected with chronic hepatitis B receiving treatment with tenofovir disoproxil fumarate tablets (N=52) or placebo (N=54) for 72 weeks. The adverse reactions observed in pediatric subjects who received treatment with tenofovir disoproxil fumarate tablets were consistent with those observed in clinical trials of tenofovir disoproxil fumarate tablets in adults. In this study, both the tenofovir disoproxil fumarate tablets and placebo treatment arms experienced an overall increase in mean lumbar spine BMD over 72 weeks, as expected for an adolescent population. The BMD gains from baseline to Week 72 in lumbar spine and total body BMD in tenofovir disoproxil fumarate-treated subjects (+5% and +3%, respectively) were less than the BMD gains observed in placebo-treated subjects (+8% and +5%, respectively). Three subjects in the tenofovir disoproxil fumarate tablets group and two subjects in the placebo group had significant (greater than 4%) lumbar spine BMD loss at Week 72. At baseline, mean BMD Z-scores in subjects randomized to tenofovir disoproxil fumarate tablets were −0.43 for lumbar spine and −0.20 for total body, and mean BMD Z-scores in subjects randomized to placebo were −0.28 for lumbar spine and −0.26 for total body. In subjects receiving tenofovir disoproxil fumarate tablets for 72 weeks, the mean change in BMD Z-score was −0.05 for lumbar spine and −0.15 for total body compared to +0.07 and +0.06, respectively, in subjects receiving placebo. As observed in pediatric studies of HIV-infected patients, skeletal growth (height) appeared to be unaffected [See Warnings and Precautions ( 5.6)]. 6.2 Postmarketing Experience The following adverse reactions have been identified during postapproval use of tenofovir disoproxil fumarate tablets. Because postmarketing reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. Immune System Disorders allergic reaction, including angioedema Metabolism and Nutrition Disorders lactic acidosis, hypokalemia, hypophosphatemia Respiratory, Thoracic, and Mediastinal Disorders dyspnea Gastrointestinal Disorders pancreatitis, increased amylase, abdominal pain Hepatobiliary Disorders hepatic steatosis, hepatitis, increased liver enzymes (most commonly AST, ALT gamma GT) Skin and Subcutaneous Tissue Disorders rash Musculoskeletal and Connective Tissue Disorders rhabdomyolysis, osteomalacia (manifested as bone pain and which may contribute to fractures), muscular weakness, myopathy Renal and Urinary Disorders acute renal failure, renal failure, acute tubular necrosis, Fanconi syndrome, proximal renal tubulopathy, interstitial nephritis (including acute cases), nephrogenic diabetes insipidus, renal insufficiency, increased creatinine, proteinuria, polyuria General Disorders and Administration Site Conditions asthenia The following adverse reactions, listed under the body system headings above, may occur as a consequence of proximal renal tubulopathy: rhabdomyolysis, osteomalacia, hypokalemia, muscular weakness, myopathy, hypophosphatemia.

12.3 Pharmacokinetics The pharmacokinetics of tenofovir DF have been evaluated in healthy volunteers and HIV-1 infected individuals. Tenofovir pharmacokinetics are similar between these populations. Absorption Tenofovir disoproxil fumarate tablets are a water soluble diester prodrug of the active ingredient tenofovir. The oral bioavailability of tenofovir from tenofovir disoproxil fumarate tablets in fasted subjects is approximately 25%. Following oral administration of a single dose of tenofovir disoproxil fumarate tablets 300 mg to HIV-1 infected subjects in the fasted state, maximum serum concentrations (C max ) are achieved in 1 ± 0.4 hrs. C max and AUC values are 0.30 ± 0.09 mcg/mL and 2.29 ± 0.69 mcg·hr/mL, respectively. The pharmacokinetics of tenofovir are dose proportional over a tenofovir disoproxil fumarate tablets dose range of 75 to 600 mg and are not affected by repeated dosing. Distribution In vitro binding of tenofovir to human plasma or serum proteins is less than 0.7 and 7.2%, respectively, over the tenofovir concentration range 0.01 to 25 mcg/mL. The volume of distribution at steady-state is 1.3 ± 0.6 L/kg and 1.2 ± 0.4 L/kg, following intravenous administration of tenofovir 1 mg/kg and 3 mg/kg. Metabolism and Elimination In vitro studies indicate that neither tenofovir disoproxil nor tenofovir are substrates of CYP enzymes. Following IV administration of tenofovir, approximately 70 to 80% of the dose is recovered in the urine as unchanged tenofovir within 72 hours of dosing. Following single dose, oral administration of tenofovir disoproxil fumarate tablets, the terminal elimination half-life of tenofovir is approximately 17 hours. After multiple oral doses of tenofovir disoproxil fumarate tablets 300 mg once daily (under fed conditions), 32 ± 10% of the administered dose is recovered in urine over 24 hours. Tenofovir is eliminated by a combination of glomerular filtration and active tubular secretion. There may be competition for elimination with other compounds that are also renally eliminated. Effects of Food on Oral Absorption Administration of tenofovir disoproxil fumarate 300 mg tablets following a high-fat meal (~700 to 1,000 kcal containing 40 to 50% fat) increases the oral bioavailability, with an increase in tenofovir AUC 0 to ∞ of approximately 40% and an increase in C max of approximately 14%. However, administration of tenofovir disoproxil fumarate tablets with a light meal did not have a significant effect on the pharmacokinetics of tenofovir when compared to fasted administration of the drug. Food delays the time to tenofovir C max by approximately 1 hour. C max and AUC of tenofovir are 0.33 ± 0.12 mcg/mL and 3.32 ± 1.37 mcg·hr/mL following multiple doses of tenofovir disoproxil fumarate tablets 300 mg once daily in the fed state, when meal content was not controlled. Special Populations Race: There were insufficient numbers from racial and ethnic groups other than Caucasian to adequately determine potential pharmacokinetic differences among these populations. Gender: Tenofovir pharmacokinetics are similar in male and female subjects. Pediatric Patients 2 Years of Age and Older: Steady-state pharmacokinetics of tenofovir were evaluated in 31 HIV-1 infected pediatric subjects 2 to less than 18 years (Table 12). Tenofovir exposure achieved in these pediatric subjects receiving oral once daily doses of tenofovir disoproxil fumarate tablets 300 mg up to a maximum dose of 300 mg was similar to exposures achieved in adults receiving once-daily doses of tenofovir disoproxil fumarate tablets 300 mg. Table 12 Mean (± SD) Tenofovir Pharmacokinetic Parameters by Age Groups for HIV-1- infected Pediatric Patients Dose and Formulation 300 mg tablet 12 to <18 Years (N=8) C max (mcg/mL) 0.38 ± 0.13 AUC tau (mcg•hr/mL) 3.39 ± 1.22 Tenofovir exposures in 52 HBV-infected pediatric subjects (12 to less than 18 years of age) receiving oral once-daily doses of tenofovir disoproxil fumarate 300 mg tablet were comparable to exposures achieved in HIV-1 infected adults and adolescents receiving once-daily doses of 300 mg. Geriatric Patients: Pharmacokinetic trials have not been performed in the elderly (65 years and older). Patients with Impaired Renal Function: The pharmacokinetics of tenofovir are altered in subjects with renal impairment [See Warnings and Precautions (5.2)]. In subjects with creatinine clearance below 50 mL/min or with end-stage renal disease (ESRD) requiring dialysis, C max , and AUC 0 to ∞ of tenofovir were increased (Table 13). It is recommended that the dosing interval for tenofovir disoproxil fumarate tablets be modified in patients with estimated creatinine clearance below 50 mL/min or in patients with ESRD who require dialysis [See Dosage and Administration ( 2.3)]. Table 13 Pharmacokinetic Parameters (Mean ± SD) of Tenofovira in Subjects with Varying Degrees of Renal Function Baseline Creatinine Clearance (mL/min) >80 ( N = 3 ) 50-80 (N=10) 30-49 ( N = 8 ) 12-29 (N=11) C max (mcg/mL) 0.34 ± 0.03 0.33 ± 0.06 0.37 ± 0.16 0.60 ± 0.19 AUC 0 to ∞ (mcg · hr/mL) 2.18 ± 0.26 3.06 ± 0.93 6.01 ± 2.50 15.98 ± 7.22 CL/F (mL/min) 1043.7 ± 115.4 807.7 ± 279.2 444.4 ± 209.8 177 ± 97.1 CL renal (mL/min) 243.5 ± 33.3 168.6 ± 27.5 100.6 ± 27.5 43 ± 31.2 a. 300 mg, single dose of tenofovir disoproxil fumarate tablets Tenofovir is efficiently removed by hemodialysis with an extraction coefficient of approximately 54%. Following a single 300 mg dose of tenofovir disoproxil fumarate tablets, a four-hour hemodialysis session removed approximately 10% of the administered tenofovir dose. Patients with Hepatic Impairment: The pharmacokinetics of tenofovir following a 300 mg single dose of tenofovir disoproxil fumarate tablets have been studied in non-HIV infected subjects with moderate to severe hepatic impairment. There were no substantial alterations in tenofovir pharmacokinetics in subjects with hepatic impairment compared with unimpaired subjects. No change in tenofovir disoproxil fumarate tablets dosing is required in patients with hepatic impairment. Assessment of Drug Interactions At concentrations substantially higher (~300-fold) than those observed in vivo, tenofovir did not inhibit in vitro drug metabolism mediated by any of the following human CYP isoforms: CYP3A4, CYP2D6, CYP2C9, or CYP2E1. However, a small (6%) but statistically significant reduction in metabolism of CYP1A substrate was observed. Based on the results of in vitro experiments and the known elimination pathway of tenofovir, the potential for CYP-mediated interactions involving tenofovir with other medicinal products is low. Tenofovir disoproxil fumarate tablets have been evaluated in healthy volunteers in combination with other antiretroviral and potential concomitant drugs. Tables 14 and 15 summarize pharmacokinetic effects of coadministered drug on tenofovir pharmacokinetics and effects of tenofovir disoproxil fumarate tablets on the pharmacokinetics of coadministered drug. TDF is a substrate of P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) transporters. When TDF is coadministered with an inhibitor of these transporters, an increase in absorption may be observed. No clinically significant drug interactions have been observed between tenofovir disoproxil fumarate tablets and efavirenz, methadone, nelfinavir, oral contraceptives, ribavirin, or sofosbuvir. Table 14 Drug Interactions: Changes in Pharmacokinetic Parameters for Tenofovira in the Presence of the Coadministered Drug Coadministered Drug Dose of Coadministered Drug (mg) N % Change of Tenofovir Pharmacokinetic Parameters b (90% CI) C max AUC C min Atazanavir c 400 once daily × 14 days 33 ↑ 14 (↑ 8 to ↑ 20) ↑ 24 (↑ 21 to ↑ 28) ↑ 22 (↑ 15 to ↑ 30) Atazanavir/ Ritonavir c 300/100 once daily 12 ↑ 34 (↑ 20 to ↑ 51) ↑ 37 (↑ 30 to ↑ 45) ↑ 29 (↑ 21 to ↑ 36) Darunavir/ Ritonavir d 300/100 twice daily 12 ↑ 24 (↑ 8 to ↑ 42) ↑ 22 (↑ 10 to ↑ 35) ↑ 37 (↑ 19 to ↑ 57) Indinavir 800 three times daily × 7 days 13 ↑ 14 (↓ 3 to ↑ 33) Û Û Ledipasvir/ Sofosbuvir e,f 90/400 once daily x 10 days 24 ↑ 47 (↑ 37 to ↑ 58) ↑ 35 (↑ 29 to ↑ 42 ) ↑ 47 (↑ 38 to ↑ 57) Ledipasvir/ Sofosbuvir e,g 23 ↑ 64 (↑ 54 to ↑ 74) ↑ 50 (↑ 42 to ↑ 59) ↑ 59 (↑ 49 to ↑ 70) Ledipasvir/ Sofosbuvir h 90/400 once daily x 14 days 15 ↑ 79 (↑ 56 to ↑ 104) ↑ 98 (↑ 77 to ↑ 123) ↑ 163 (↑ 132 to ↑197) Lopinavir/ Ritonavir 400/100 twice daily × 14 days 24 Û ↑ 32 (↑ 25 to ↑ 38) ↑ 51 (↑ 37 to ↑ 66) Saquinavir/ Ritonavir 1,000/100 twice daily × 14 days 35 Û Û ↑ 23 (↑ 16 to ↑ 30) Sofosbuvir i 400 single dose 16 ↑ 25 (↑ 8 to ↑ 45) Û Û Sofosbuvir/ Velpatasvir j 400/100 once daily 24 ↑ 44 (↑ 33 to ↑ 55) ↑ 40 (↑ 34 to ↑ 46) ↑ 84 (↑ 76 to ↑ 92) Sofosbuvir/ Velpatasvir k 400/100 once daily 30 ↑ 46 (↑ 39 to ↑ 54) ↑ 40 (↑ 34 to ↑ 45) ↑ 70 (↑ 61 to ↑ 79) Sofosbuvir/ Velpatasvir/ Voxilaprevir l 400/100/100 + Voxilaprevirm 100 once daily 29 ↑ 48 (↑ 36 to ↑ 61) ↑ 39 (↑ 32 to↑ 46) ↑ 47 (↑ 38 to ↑ 56) Tacrolimus 0.05 mg/kg twice Daily × 7 days 21 ↑ 13 (↑ 1 to ↑ 27) Û Û Tipranavir/ Ritonavir n 500/100 twice daily 22 ↓ 23 (↓ 32 to ↓ 13) ↓ 2 (↓ 9 to ↑ 5) ↑ 7 (↓ 2 to ↑ 17) 750/200 twice daily (23 doses) 20 ↓ 38 (↓ 46 to ↓ 29) ↑ 2 (↓ 6 to ↑ 10) ↑ 14 (↑ 1 to ↑ 27) a. Subjects received tenofovir disoproxil fumarate tablets 300 mg once daily. b. Increase = ↑; Decrease = ↓; No Effect = Û c. Reyataz Prescribing Information. d. Prezista Prescribing Information. e Data generated from simultaneous dosing with HARVONI (ledipasvir/sofosbuvir). Staggered administration (12 hours apart) provided similar results. f. Comparison based on exposures when administered as atazanavir/ritonavir + emtricitabine/tenofovir DF. g. Comparison based on exposures when administered as darunavir/ritonavir + emtricitabine/tenofovir DF. h. Study conducted with ATRIPLA (efavirenz/emtricitabine/tenofovir DF) coadministered with HARVONI; coadministration with HARVONI also results in comparable increases in tenofovir exposure when TDF is administered as COMPLERA, or TRUVADA + dolutegravir. i. Study conducted with ATRIPLA coadministered with SOVALDI ® (sofosbuvir). j. Study conducted with COMPLERA coadministered with EPCLUSA; coadministration with EPCLUSA also results in comparable increases in tenofovir exposures when TDF is administered as ATRIPLA, STRIBILD, TRUVADA + atazanavir/ritonavir, or TRUVADA + darunavir/ritonavir. k. Administered as raltegravir + emtricitabine/tenofovir DF. l. Comparison based on exposures when administered as darunavir/ritonavir + emtricitabine/tenofovir DF. m. Study conducted with additional voxilaprevir 100 mg to achieve voxilaprevir exposures expected in HCV-infected patients. n. Aptivus Prescribing Information. No effect on the pharmacokinetic parameters of the following coadministered drugs was observed with tenofovir disoproxil fumarate: abacavir, didanosine (buffered tablets), emtricitabine, entecavir, and lamivudine. Table 15 Drug Interactions: Changes in Pharmacokinetic Parameters for Coadministered Drug in the Presence of Tenofovir disoproxil fumarate Tablets Coadministered Drug Dose of Coadministered Drug (mg) N % Change of Coadministered Drug Pharmacokinetic Parameters a (90% CI) C max A UC C min Abacavir 300 once 8 ­ 12 (¯ 1 to ­26) Û NA Atazanavirb 400 once daily x 14 days 34 ¯21 (¯27 to ¯ 14) ¯25 (¯30 to ¯19) ¯ 40 (¯ 48 to ¯ 32) Atazanavirb Atazanavir/Ritonavir 300/100 once daily x 42 days 10 ¯28 (¯ 50 to­ 5) ¯25c (¯42 to ¯ 3) ¯23c (¯46 to ­10) Darunavir d Darunavir/Ritonavir 300/100 once daily 12 ­ 16 (¯ to ­ 42) ­ 21 (¯ to ­ 54) ­ 24 (¯ to ­ 69) Didanosine e 250 once, simultaneously with tenofovir disoproxil fumarate tablets and a light meal f 33 ¯ 20 g (¯ 32 to ¯ 7) Û g NA Emtricitabine 200 once daily x 7 days 17 Û Û ­ 20 (­ 12 to ­ 29) Entecavir 1 mg once daily x 10 days 28 Û ­ 13 ( ­ to ­ 15) Û Indinavir 800 three times daily x 7 days 12 ¯ 11 (¯ 30 to ­12) Û Û Lamivudine 150 twice daily x 7 days 15 24 (¯ 34 to ¯ 12) Û Û Lopinavir Ritonavir Lopinavir/Ritonavir 400/100 twice daily x 14 days 24 Û Û Û Û Û Û Saquinavir Ritonavir Saquinavir/Ritonavir 1,000/100 twice daily x 14 days 32 ­ 22 ( ­ 6 to ­ 41) Û ­ 29 h ( ­ 12 to ­ 48) Û ­ 47 h ( ­ 23 to ­ 76) ­ 23 ( ­ 3 to ­ 46) Tacrolimus 0.05 mg/kg twice daily x 7 days 21 Û Û Û Tipranavir i Tipranavir/Ritonavir 500/100 twice daily 22 ¯ 17 (¯ 26 to¯ 6) ¯ 18 (¯ 25 to ¯ 9) ¯ 21 (¯ 30 to ¯ 10) Tipranavir/Ritonavir 750/200 twice daily (23 doses) 20 ¯ 11 (¯ 16 to ¯ 4) ¯ 9 (¯ 15 to ¯ 3) ¯ 12 (¯ 22 to0) a. Increase = ↑; Decrease = ↓; No Effect = Û; NA = Not Applicable b. Reyataz Prescribing Information. c. In HIV-infected subjects, addition of tenofovir DF to atazanavir 300 mg plus ritonavir 100 mg, resulted in AUC and C min values of atazanavir that were 2.3- and 4-fold higher than the respective values observed for atazanavir 400 mg when given alone. d. Prezista Prescribing Information. e. Videx EC Prescribing Information. Subjects received didanosine enteric-coated capsules. f. 373 kcal, 8.2 g fat g. Compared with didanosine (enteric-coated) 400 mg administered alone under fasting conditions. h. Increases in AUC and C min are not expected to be clinically relevant; hence no dose adjustments are required when tenofovir DF and ritonavir-boosted saquinavir are coadministered. i. Aptivus Prescribing Information.