TENOFOVIR ALAFENAMIDE: 2,990 Adverse Event Reports & Safety Profile

VEMLIDY is a tablet containing tenofovir alafenamide for oral administration. Tenofovir alafenamide, a hepatitis B virus (HBV) nucleoside analog reverse transcriptase inhibitor, is converted in vivo to tenofovir, an acyclic nucleoside phosphonate (nucleotide) analog of adenosine 5′-monophosphate. Each tablet contains 25 mg of tenofovir alafenamide (equivalent to 28 mg of tenofovir alafenamide fumarate). The tablets include the following inactive ingredients: croscarmellose sodium, lactose monohydrate, magnesium stearate, and microcrystalline cellulose. The tablets are film coated with a coating material containing: iron oxide yellow, polyethylene glycol, polyvinyl alcohol, talc, and titanium dioxide. The chemical name of tenofovir alafenamide fumarate drug substance is L-alanine, N -[( S )-[[(1 R )-2-(6-amino-9 H -purin-9-yl)-1-methylethoxy]methyl]phenoxyphosphinyl]-, 1-methylethyl ester, (2 E )-2-butenedioate (2:1). It has an empirical formula of C 21 H 29 O 5 N 6 P∙½(C 4 H 4 O 4 ) and a formula weight of 534.50. It has the following structural formula: Tenofovir alafenamide fumarate is a white to off-white or tan powder with a solubility of 4.7 mg per mL in water at 20 °C.

Chemical

Structure

AND USAGE VEMLIDY is indicated for the treatment of chronic hepatitis B virus (HBV) infection in adults and pediatric patients 6 years of age and older and weighing at least 25 kg with compensated liver disease [see Clinical Studies (14) ] . VEMLIDY is a hepatitis B virus (HBV) nucleoside analog reverse transcriptase inhibitor and is indicated for the treatment of chronic hepatitis B virus infection in adults and pediatric patients 6 years of age and older and weighing at least 25 kg with compensated liver disease. ( 1 )

AND ADMINISTRATION Testing: Prior to initiation of VEMLIDY, test patients for HIV infection. VEMLIDY alone should not be used in patients with HIV infection. Prior to or when initiating VEMLIDY, and during treatment on a clinically appropriate schedule, assess serum creatinine, estimated creatinine clearance, urine glucose, and urine protein in all patients. Also assess serum phosphorus in patients with chronic kidney disease. ( 2.1 ) Recommended dosage: 25 mg (one tablet) taken orally once daily with food. ( 2.2 )

Renal

Impairment: VEMLIDY is not recommended in patients with estimated creatinine clearance below 15 mL per minute who are not receiving chronic hemodialysis. In patients on chronic hemodialysis, on hemodialysis days, administer VEMLIDY after hemodialysis. ( 2.3 )

Hepatic

Impairment: VEMLIDY is not recommended in patients with decompensated (Child-Pugh B or C) hepatic impairment. ( 2.4 )

2.1 Testing Prior to Initiation of VEMLIDY Prior to initiation of VEMLIDY, patients should be tested for HIV-1 infection. VEMLIDY alone should not be used in patients with HIV-1 infection <span class="opacity-50 text-xs">[see Warnings and Precautions (5.2) ]</span> . Prior to or when initiating VEMLIDY, and during treatment with VEMLIDY 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 <span class="opacity-50 text-xs">[see Warnings and Precautions (5.3) ]</span>.

2.2 Recommended Dosage in Adults and Pediatric Patients 6 Years of Age and Older and Weighing at Least 25 kg The recommended dosage of VEMLIDY in adults and pediatric patients 6 years of age and older and weighing at least 25 kg is one 25 mg tablet taken orally once daily with food <span class="opacity-50 text-xs">[see Clinical Pharmacology (12.3) ]</span>.

2.3 Dosage in Patients with Renal Impairment No dosage adjustment of VEMLIDY is required in patients with estimated creatinine clearance greater than or equal to 15 mL per minute, or in patients with end stage renal disease (ESRD; estimated creatinine clearance below 15 mL per minute) who are receiving chronic hemodialysis. On days of hemodialysis, administer VEMLIDY after completion of hemodialysis treatment. VEMLIDY is not recommended in patients with ESRD who are not receiving chronic hemodialysis <span class="opacity-50 text-xs">[see Use in Specific Populations (8.6) and Clinical Pharmacology (12.3) ]</span> . No data are available to make dose recommendations in pediatric patients with renal impairment.

2.4 Dosage in Patients with Hepatic Impairment No dosage adjustment of VEMLIDY is required in patients with mild hepatic impairment (Child-Pugh A). VEMLIDY is not recommended in patients with decompensated (Child-Pugh B or C) hepatic impairment <span class="opacity-50 text-xs">[see Use in Specific Populations (8.7) and Clinical Pharmacology (12.3) ]</span>.

None. None. ( 4 )

REACTIONS The following adverse reactions are discussed in other sections of the labeling: Severe Acute Exacerbation of Hepatitis B [see Warnings and Precautions (5.1) ]

New

Onset or Worsening of Renal Impairment [see Warnings and Precautions (5.3) ]

Lactic Acidosis/Severe

Hepatomegaly with Steatosis [see Warnings and Precautions (5.4) ] Most common adverse reaction (incidence greater than or equal to 10%, all grades) is headache. ( 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 in Adult Subjects with Chronic Hepatitis B and Compensated Liver Disease The safety assessment of VEMLIDY was based on pooled data through the Week 96 data analysis from 1298 subjects in two randomized, double-blind, active-controlled trials, Trial 108 and Trial 110, in adult subjects with chronic hepatitis B and compensated liver disease. A total of 866 subjects received VEMLIDY 25 mg once daily [see Clinical Studies (14.2) ] . Further safety assessment was based on pooled data from Trials 108 and 110 from subjects who continued to receive their original blinded treatment through Week 120 and additionally from subjects who received open-label VEMLIDY from Week 96 through Week 120 (n = 361 remained on VEMLIDY; n = 180 switched from TDF to VEMLIDY at Week 96). Based on the Week 96 analysis, the most common adverse reaction (all Grades) reported in at least 10% of subjects in the VEMLIDY group was headache. The proportion of subjects who discontinued treatment with VEMLIDY or TDF due to adverse reactions of any severity was 1.5% and 0.9%, respectively.

Table

1 displays the frequency of the adverse reactions (all Grades) greater than or equal to 5% in the VEMLIDY group.

Table

1 Adverse Reactions Frequencies of adverse reactions are based on all treatment-emergent adverse events, regardless of relationship to study drug. (All Grades) Reported in ≥5% of Subjects with Chronic HBV Infection and Compensated Liver Disease in Trials 108 and 110 (Week 96 analysis Double-blind phase. ) VEMLIDY (N=866) TDF (N=432)

Headache

12% 10% Abdominal pain Grouped term including abdominal pain upper, abdominal pain, abdominal pain lower, and abdominal tenderness. 9% 6% Cough 8% 8% Back pain 6% 6% Fatigue 6% 5% Nausea 6% 6% Arthralgia 5% 6% Diarrhea 5% 5% Dyspepsia 5% 5% Additional adverse reactions occurring in less than 5% of subjects in Trials 108 and 110 included vomiting, rash, and flatulence. The safety profile of VEMLIDY in subjects who continued to receive blinded treatment through Week 120 was similar to that at Week 96. The safety profile of VEMLIDY in subjects who remained on VEMLIDY in the open-label phase through Week 120 was similar to that in subjects who switched from TDF to VEMLIDY at Week 96.

Renal Laboratory

Tests In a pooled analysis of Trials 108 and 110 in adult subjects with chronic hepatitis B and a median baseline estimated creatinine clearance between 106 and 105 mL per minute (for the VEMLIDY and TDF groups, respectively), mean serum creatinine increased by less than 0.1 mg/dL and median serum phosphorus decreased by 0.1 mg/dL in both treatment groups at Week 96. Median change from baseline to Week 96 in estimated creatinine clearance was -1.2 mL per minute in the VEMLIDY group and -4.8 mL per minute in those receiving TDF. In subjects who remained on blinded treatment beyond Week 96 in Trials 108 and 110, change from baseline in renal laboratory parameter values in each group at Week 120 were similar to those at Week 96. In the open-label phase, median change in estimated creatinine clearance by Cockcroft-Gault method from Week 96 to Week 120 was -0.6 mL per minute in subjects who remained on VEMLIDY and +1.8 mL per minute in those who switched from TDF to VEMLIDY at Week 96. Mean serum creatinine and median serum phosphorus values at Week 120 were similar to those at Week 96 in subjects who remained on VEMLIDY and in subjects who switched from TDF to VEMLIDY. The long-term clinical significance of these renal laboratory changes on adverse reaction frequencies between VEMLIDY and TDF is not known.

Bone Mineral Density

Effects In a pooled analysis of Trials 108 and 110, the mean percentage change in bone mineral density (BMD) from baseline to Week 96 as assessed by dual-energy X-ray absorptiometry (DXA) was -0.7% with VEMLIDY compared to -2.6% with TDF at the lumbar spine and -0.3% compared to -2.5% at the total hip. BMD declines of 5% or greater at the lumbar spine were experienced by 11% of VEMLIDY subjects and 25% of TDF subjects at Week 96. BMD declines of 7% or greater at the femoral neck were experienced by 5% of VEMLIDY subjects and 13% of TDF subjects at Week 96. In subjects who remained on blinded treatment beyond Week 96 in Trials 108 and 110, mean percentage change in BMD in each group at Week 120 was similar to that at Week 96. In the open-label phase, mean percentage change in BMD from Week 96 to Week 120 in subjects who remained on VEMLIDY was 0.6% at the lumbar spine and 0% at the total hip, compared to 1.7% at the lumbar spine and 0.6% at the total hip in those who switched from TDF to VEMLIDY. The long-term clinical significance of these BMD changes is not known.

Laboratory Abnormalities

The frequency of laboratory abnormalities (Grades 3–4) occurring in at least 2% of subjects receiving VEMLIDY in Trials 108 and 110 are presented in Table 2.

Table

2 Laboratory Abnormalities (Grades 3–4) Reported in ≥2% of Subjects with Chronic HBV Infection and Compensated Liver Disease in Trials 108 and 110 (Week 96 analysis Double-blind phase. )

Laboratory Parameter Abnormality

Frequencies are based on treatment-emergent laboratory abnormalities. VEMLIDY (N=866) TDF (N=432) ULN=Upper Limit of Normal ALT (>5 × ULN) 8% 10% LDL-cholesterol (fasted) (>190 mg/dL) 6% 1% Glycosuria (≥3+) 5% 2% AST (>5 × ULN) 3% 5% Creatine Kinase (≥10 × ULN) 3% 3% Serum Amylase (>2.0 × ULN) 3% 3% The overall incidence of blinded treatment ALT flares (defined as confirmed serum ALT greater than 2 × baseline and greater than 10 × ULN at 2 consecutive postbaseline visits, with or without associated symptoms) was similar between VEMLIDY (0.6%) and TDF (0.9%) through Week 96. ALT flares generally were not associated with coincident elevations in bilirubin, occurred within the first 12 weeks of treatment, and resolved without recurrence. Based on the Week 120 analysis, the frequencies of lab abnormalities in subjects who remained on VEMLIDY in the open-label phase were similar to those in subjects who switched from TDF to VEMLIDY at Week 96. Amylase and Lipase Elevations and Pancreatitis At Week 96, in Trials 108 and 110, eight subjects treated with VEMLIDY with elevated amylase levels had associated symptoms, such as nausea, low back pain; abdominal tenderness, pain, and distension; and biliary pancreatitis and pancreatitis. Of these eight, two subjects discontinued VEMLIDY due to elevated amylase and/or lipase; one subject experienced recurrence of adverse events when VEMLIDY was restarted. No subject treated with TDF had associated symptoms or discontinued treatment.

From Week

96 to Week 120, one additional subject who continued open-label VEMLIDY and none of the subjects who switched from TDF to VEMLIDY had elevated amylase levels and associated symptoms.

Serum Lipids

Changes from baseline in total cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides, and total cholesterol to HDL ratio among subjects treated with VEMLIDY and TDF in Trials 108 and 110 are presented in Table 3.

Table

3 Lipid Abnormalities: Mean Change from Baseline in Lipid Parameters in Patients with Chronic HBV Infection and Compensated Liver Disease in Trials 108 and 110 (Week 96 analysis) VEMLIDY (N=866) TDF (N=432)

Baseline Week

96 Baseline Week 96 mg/dL Change The change from baseline is the mean of within-subject changes from baseline for subjects with both baseline and Week 96 values. mg/dL Change Total Cholesterol (fasted) 188 [n=835] -1 [n=742] 193 [n=423] -25 [n=368] HDL-Cholesterol (fasted) 60 [n=835] -5 [n=740] 61 [n=423] -12 [n=368] LDL-Cholesterol (fasted) 116 [n=835] +7 [n=741] 120 [n=423] -10 [n=368] Triglycerides (fasted) 102 [n=836] +13 [n=743] 102 [n=423] -7 [n=368]

Total

Cholesterol to HDL ratio 3 [n=835] 0 [n=740] 3 [n=423] 0 [n=368] In the open-label phase, lipid parameters at Week 120 in subjects who remained on VEMLIDY were similar to those at Week 96. In subjects who switched from TDF to VEMLIDY, mean change from Week 96 to Week 120 in total cholesterol was 23 mg/dL, HDL-cholesterol was 5 mg/dL, LDL-cholesterol was 16 mg/dL, triglycerides was 30 mg/dL, and total cholesterol to HDL ratio was 0 mg/dL.

Adverse

Reactions in Virologically Suppressed Adult Subjects with Chronic Hepatitis B The safety of VEMLIDY in virologically suppressed adults is based on Week 48 data from a randomized, double-blind, active-controlled trial (Trial 4018) in which subjects taking TDF at baseline were randomized to switch to VEMLIDY (N=243) or to continue their TDF treatment (N=245). Adverse reactions observed with VEMLIDY in Trial 4018 were similar to those in Trials 108 and 110 [see Clinical Studies (14.3) ].

Renal Laboratory

Tests, Bone Mineral Density Effects, and Serum Lipids In virologically suppressed adults in Trial 4018, changes from baseline in renal function, BMD, and lipid parameters in the VEMLIDY and TDF groups at Week 48 were similar to those observed in Trials 108 and 110 at Week 96.

Adverse

Reactions in Adult Subjects with Chronic Hepatitis B and Renal Impairment In an open-label trial (Trial 4035) in virologically suppressed adult subjects with chronic hepatitis B switching to VEMLIDY 25 mg, the safety of VEMLIDY was assessed in 78 subjects with moderate to severe renal impairment (estimated creatinine clearance between 15 and 59 mL per minute by Cockcroft-Gault method; Part A, Cohort 1) and 15 subjects with ESRD (estimated creatinine clearance below 15 mL per minute) receiving chronic hemodialysis (Part A, Cohort 2). The safety of VEMLIDY, including changes from baseline in renal function, BMD, and lipid parameters, was similar to that observed in clinical trials of VEMLIDY in subjects with compensated liver disease but without renal impairment [see Use in Specific Populations (8.6) and Clinical Studies (14.4) ].

Adverse

Reactions in Pediatric Subjects with Chronic Hepatitis B The safety of VEMLIDY was evaluated in HBV-infected treatment-naïve and treatment-experienced pediatric subjects between the ages of 12 to less than 18 years and weighing at least 35 kg (Cohort 1; N=70) and 6 to less than 12 years and weighing at least 25 kg (Cohort 2, Group 1: N=18) through Week 24 in a randomized, double-blind, placebo-controlled clinical trial (Trial 1092). Subjects were then eligible to roll over to receive open-label VEMLIDY. Safety data are available through Week 96 [see Clinical Studies (14.5) ]. The safety profile of VEMLIDY was similar to that in adults.

Bone Mineral Density Effects

Among the Cohort 1 and Cohort 2, Group 1 subjects treated with VEMLIDY and placebo, the mean percent change in BMD from baseline to Week 24 was 1.6% (N=48) and 1.9% (N=23) for lumbar spine, and 1.9% (N=50) and 2.0% (N=23) for whole body, respectively.

At Week

24, mean changes from baseline BMD Z-scores were 0.01 and -0.07 for lumbar spine, and -0.04 and -0.04 for whole body, for the VEMLIDY and placebo groups, respectively.

At Week

24, BMD declines of 4% or greater at lumbar spine and whole body were experienced by 6% and 2% of VEMLIDY subjects, respectively. In the open-label phase, mean percentage change in lumbar spine and whole body BMD and BMD Z-scores from baseline to Week 96 was similar in subjects who remained on VEMLIDY compared to those who switched from placebo to VEMLIDY.

6.2 Postmarketing Experience The following adverse reactions have been identified during post approval use of VEMLIDY or other products containing tenofovir alafenamide. Because these 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. Skin and Subcutaneous Tissue Disorders Angioedema, urticaria Renal and Urinary Disorders Acute renal failure, acute tubular necrosis, proximal renal tubulopathy, and Fanconi syndrome

AND PRECAUTIONS HBV and HIV-1 coinfection: VEMLIDY alone is not recommended for the treatment of HIV-1 infection. HIV-1 resistance may develop in these patients. ( 5.2 ) New onset or worsening renal impairment: Prior to or when initiating VEMLIDY, and during treatment on a clinically appropriate schedule, assess serum creatinine, estimated creatinine clearance, urine glucose, and urine protein in all patients. Also assess serum phosphorus in patients with chronic kidney disease. ( 5.3 ) Lactic acidosis/severe hepatomegaly with steatosis: Discontinue treatment in patients who develop symptoms or laboratory findings suggestive of lactic acidosis or pronounced hepatotoxicity. ( 5.4 )

5.1 Severe Acute Exacerbation of Hepatitis B after Discontinuation of Treatment Discontinuation of anti-hepatitis B therapy, including VEMLIDY, may result in severe acute exacerbations of hepatitis B. Patients who discontinue VEMLIDY 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.

5.2 Risk of Development of HIV-1 Resistance in Patients Coinfected with HBV and HIV-1 Due to the risk of development of HIV-1 resistance, VEMLIDY alone is not recommended for the treatment of HIV-1 infection. The safety and efficacy of VEMLIDY have not been established in patients coinfected with HBV and HIV-1. HIV antibody testing should be offered to all HBV-infected patients before initiating therapy with VEMLIDY, and, if positive, an appropriate antiretroviral combination regimen that is recommended for patients coinfected with HIV-1 should be used.

5.3 New Onset or Worsening Renal Impairment Postmarketing cases of renal impairment, including acute renal failure, proximal renal tubulopathy (PRT), and Fanconi syndrome have been reported with TAF-containing products; while most of these cases were characterized by potential confounders that may have contributed to the reported renal events, it is also possible these factors may have predisposed patients to tenofovir-related adverse events <span class="opacity-50 text-xs">[see Adverse Reactions (6.2) ]</span>. Patients taking tenofovir prodrugs who have impaired renal function and those taking nephrotoxic agents, including non-steroidal anti-inflammatory drugs, are at increased risk of developing renal-related adverse reactions <span class="opacity-50 text-xs">[see Drug Interactions (7.2) ]</span> . Prior to or when initiating VEMLIDY, and during treatment with VEMLIDY 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. Discontinue VEMLIDY in patients who develop clinically significant decreases in renal function or evidence of Fanconi syndrome <span class="opacity-50 text-xs">[see Adverse Reactions (6.1) and Use in Specific Populations (8.6) ]</span> .

5.4 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 tenofovir disoproxil fumarate (TDF), another prodrug of tenofovir, alone or in combination with other antiretrovirals. Treatment with VEMLIDY 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).

INTERACTIONS VEMLIDY is a substrate of P-glycoprotein (P-gp) and BCRP. Drugs that strongly affect P-gp and BCRP activity may lead to changes in VEMLIDY absorption. Consult the full prescribing information prior to and during treatment for potential drug-drug interactions. ( 7 )

7.1 Potential for Other Drugs to Affect VEMLIDY VEMLIDY is a substrate of P-glycoprotein (P-gp) and BCRP. Drugs that strongly affect P-gp and BCRP activity may lead to changes in tenofovir alafenamide absorption (see Table 4 ). Drugs that induce P-gp activity are expected to decrease the absorption of tenofovir alafenamide, resulting in decreased plasma concentrations of tenofovir alafenamide, which may lead to loss of therapeutic effect of VEMLIDY. Coadministration of VEMLIDY with other drugs that inhibit P-gp and BCRP may increase the absorption and plasma concentration of tenofovir alafenamide.

7.2 Drugs Affecting Renal Function Because tenofovir is primarily excreted by the kidneys by a combination of glomerular filtration and active tubular secretion, coadministration of VEMLIDY with drugs that reduce renal function or compete for active tubular secretion may increase concentrations of tenofovir and other renally eliminated drugs and this may increase the risk of adverse reactions. Some examples of drugs that are eliminated by active tubular secretion include, but are not limited to, acyclovir, cidofovir, ganciclovir, valacyclovir, valganciclovir, aminoglycosides (e.g., gentamicin), and high-dose or multiple NSAIDs <span class="opacity-50 text-xs">[see Warnings and Precautions (5.3) ]</span> .

7.3 Established and Other Potentially Significant Interactions Table 4 provides a listing of established or potentially clinically significant drug interactions. The drug interactions described are based on studies conducted with tenofovir alafenamide or are predicted drug interactions that may occur with VEMLIDY [For magnitude of interaction, see Clinical Pharmacology (12.3) ] . Information regarding potential drug-drug interactions with HIV antiretrovirals is not provided (see the prescribing information for emtricitabine/tenofovir alafenamide for interactions with HIV antiretrovirals). The table includes potentially significant interactions but is not all inclusive.

Table

4 Established and Other Potentially Significant Drug Interactions This table is not all inclusive.

Concomitant Drug

Class: Drug Name Effect on Concentration ↓ = decrease.

Clinical Comment

Anticonvulsants: ↓ tenofovir alafenamide When coadministered with carbamazepine, the tenofovir alafenamide dose should be increased to two tablets once daily. Coadministration of VEMLIDY with oxcarbazepine, phenobarbital, or phenytoin is not recommended.

Carbamazepine

Indicates that a drug interaction study was conducted. P-gp inducer Oxcarbazepine Phenobarbital Phenytoin Antimycobacterials: ↓ tenofovir alafenamide Coadministration of VEMLIDY with rifabutin, rifampin or rifapentine is not recommended.

Rifabutin Rifampin Rifapentine Herbal

Products: ↓ tenofovir alafenamide Coadministration of VEMLIDY with St. John's wort is not recommended. St. John's wort (Hypericum perforatum)

7.4 Drugs without Clinically Significant Interactions with VEMLIDY Based on drug interaction studies conducted with VEMLIDY, no clinically significant drug interactions have been observed with: ethinyl estradiol, ledipasvir/sofosbuvir, midazolam, norgestimate, sertraline, sofosbuvir, sofosbuvir/velpatasvir, and sofosbuvir/velpatasvir/voxilaprevir.