Truvada
TRUVADA®
(emtricitabine/tenofovir disoproxil fumarate) Tablets
WARNINGS: LACTIC ACIDOSIS/SEVERE HEPATOMEGALY WITH STEATOSIS and POST TREATMENT ACUTE EXACERBATION OF HEPATITIS B.
Lactic acidosis and severe hepatomegaly with steatosis, including fatal cases, have been reported with the use of nucleoside analogs alone or in combination with other antiretrovirals [See WARNINGS and PRECAUTIONS].
TRUVADA is not approved for the treatment of chronic hepatitis B virus (HBV) infection and the safety and efficacy of TRUVADA have not been established in patients coinfected with HBV and HIV-1. Severe acute exacerbations of hepatitis B have been reported in patients who are coinfected with HBV and HIV-1 and have discontinued EMBRIVA or VIREAD, the components of TRUVADA. Hepatic function should be monitored closely with both clinical and laboratory follow-up for at least several months in patients who are coinfected with HIV-1 and HBV and discontinue TRUVADA. If appropriate, initiation of anti-hepatitis B therapy may be warranted [See WARNINGS and PRECAUTIONS].
DRUG DESCRIPTION
TRUVADA tablets are fixed dose combination tablets containing emtricitabine and tenofovir disoproxil fumarate. EMTRIVA is the brand name for emtricitabine, a synthetic nucleoside analog of cytidine. Tenofovir disoproxil fumarate (tenofovir DF) is converted in vivo to tenofovir, an acyclic nucleoside phosphonate (nucleotide) analog of adenosine 5'-monophosphate. Both emtricitabine and tenofovir exhibit inhibitory activity against HIV-1 reverse transcriptase.
Emtricitabine: The chemical name of emtricitabine is 5-fluoro-1-(2R,5S)-[2-(hydroxymethyl)-1,3-oxathiolan-5-yl]cytosine. Emtricitabine is the (-) enantiomer of a thio analog of cytidine, which differs from other cytidine analogs in that it has a fluorine in the 5-position.
It has a molecular formula of C8H10FN3O3S and a molecular weight of 247.24. It has the following structural formula:
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Emtricitabine is a white to off-white crystalline powder with a solubility of approximately 112 mg/mL in water at 25 ° C. The partition coefficient (log p) for emtricitabine is -0.43 and the pKa is 2.65.
Tenofovir Disoproxil Fumarate: Tenofovir disoproxil fumarate is a fumaric acid salt of the bis-isopropoxycarbonyloxymethyl ester derivative of tenofovir. The chemical name of tenofovir disoproxil fumarate is 9-[(R)-2 [[bis[[(isopropoxycarbonyl)oxy]- methoxy]phosphinyl]methoxy]propyl]adenine fumarate (1:1). It has a molecular formula of C19H30N5O10P•C4H4O4 and a molecular weight of 635.52. It has the following structural formula:
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Tenofovir disoproxil fumarate is a white to off-white crystalline powder with a solubility of 13.4 mg/mL in water at 25 °C. The partition coefficient (log p) for tenofovir disoproxil is 1.25 and the pKa is 3.75. All dosages are expressed in terms of tenofovir disoproxil fumarate except where otherwise noted.
TRUVADA tablets are for oral administration. Each film-coated tablet contains 200 mg of emtricitabine and 300 mg of tenofovir disoproxil fumarate, (which is equivalent to 245 mg of tenofovir disoproxil), as active ingredients. The tablets also include the following inactive ingredients: croscarmellose sodium, lactose monohydrate, magnesium stearate, microcrystalline cellulose, and pregelatinized starch (gluten free). The tablets are coated with Opadry II Blue Y-30-10701, which contains FD&C Blue #2 aluminum lake, hydroxypropyl methylcellulose 2910, lactose monohydrate, titanium dioxide, and triacetin.
INDICATIONS
TRUVADA®, a combination of EMTRIVA® and VIREAD®, is indicated in combination with other antiretroviral agents (such as non-nucleoside reverse transcriptase inhibitors or protease inhibitors) for the treatment of HIV-1 infection in adults. Additional important information regarding the use of TRUVADA for the treatment of HIV-1 infection:
- It is not recommended that TRUVADA be used as a component of a triple nucleoside regimen.
- TRUVADA should not be coadministered with ATRIPLA®, EMTRIVA, VIREAD or lamivudine-containing products [See WARNINGS and PRECAUTIONS].
- In treatment experienced patients, the use of TRUVADA should be guided by laboratory testing and treatment history [See CLINICAL PHARMACOLOGY].
DOSAGE AND ADMINISTRATION
Recommended Dose
The dose of TRUVADA is one tablet (containing 200 mg of emtricitabine and 300 mg of tenofovir disoproxil fumarate) once daily taken orally with or without food.
Dose Adjustment for Renal Impairment
Significantly increased drug exposures occurred when EMTRIVA or VIREAD were administered to patients with moderate to severe renal impairment [see EMTRIVA or VIREAD Package Insert]. Therefore, the dosing interval of TRUVADA should be adjusted in patients with baseline creatinine clearance 30-49 mL/min using the recommendations in Table 1. These dosing interval recommendations are based on modeling of single-dose pharmacokinetic data in non-HIV infected subjects. The safety and effectiveness of these dosing interval adjustment recommendations have not been clinically evaluated in patients with moderate renal impairment, therefore clinical response to treatment and renal function should be closely monitored in these patients [See WARNINGS and PRECAUTIONS].
No dose adjustment is necessary for patients with mild renal impairment (creatinine clearance 50-80 mL/min). Routine monitoring of calculated creatinine clearance and serum phosphorus should be performed in patients with mild renal impairment [See WARNINGS and PRECAUTIONS].
Table 1: Dosage Adjustment for Patients with Altered Creatinine
Clearance
| Creatinine Clearance (mL/min)a | |||
| ≥ 50 | 30-49 | <30 (Including Patients Requiring Hemodialysis) | |
| Recommended Dosing Interval | Every 24 hours | Every 48 hours | TRUVADA should not be administered. |
| a. Calculated using ideal (lean) body weight | |||
HOW SUPPLIED
Dosage Forms And Strengths
TRUVADA is available as tablets. Each tablet contains 200 mg of emtricitabine and 300 mg of tenofovir disoproxil fumarate (which is equivalent to 245 mg of tenofovir disoproxil). The tablets are blue, capsule-shaped, film-coated, debossed with "GILEAD" on one side and with "701" on the other side.
The blue, capsule-shaped, film-coated, tablets contain 200 mg of emtricitabine and 300 mg of tenofovir disoproxil fumarate (which is equivalent to 245 mg of tenofovir disoproxil), are debossed with "GILEAD" on one side and with "701" on the other side, and are available in unit of use bottles (containing a dessicant [silica gel canister or sachet] and closed with a child-resistant closure) of:
- 30 tablets (NDC 61958-0701-1)
Store at 25 °C (77 °F), excursions permitted to 15-30 °C (59-86 °F) (see USP Controlled Room Temperature).
- Keep container tightly closed
- Dispense only in original container
- Do not use if seal over bottle opening is broken or missing.
TRUVADA, EMTRIVA, and VIREAD are registered trademarks of Gilead Sciences, Inc. ATRIPLA is a trademark of Bristol-Myers Squibb & Gilead Sciences, LLC. All other trademarks referenced herein are the property of their respective owners. MAY08. FDA rev date: 5/16/2008
SIDE EFFECTS
The following adverse reactions are discussed in other sections of the labeling:
- Lactic acidosis/severe hepatomegaly with steatosis [See Boxed Warning, WARNINGS and PRECAUTIONS].
- Severe acute exacerbations of Hepatitis B [See Boxed Warning, WARNINGS and PRECAUTIONS].
- New onset or worsening renal impairment [See WARNINGS and PRECAUTIONS].
- Decreases in bone mineral density [See WARNINGS and PRECAUTIONS].
- Immune reconstitution syndrome [See WARNINGS and PRECAUTIONS].
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.
The most common adverse reactions (incidence ≥ 10%, any severity) occurring in Study 934, an active-controlled clinical study of efavirenz, emtricitabine, and tenofovir disoproxil fumarate, include diarrhea, nausea, fatigue, headache, dizziness, depression, insomnia, abnormal dreams, and rash. See also Table 2 for the frequency of treatment-emergent adverse reactions (Grade 2-4) occurring in ≥ 5% of patients treated with efavirenz, emtricitabine, and tenofovir disoproxil fumarate in this study.
Skin discoloration, manifested by hyperpigmentation on the palms and/or soles was generally mild and asymptomatic. The mechanism and clinical significance are unknown.
Study 934 - Treatment Emergent Adverse Reactions: In Study 934, 511 antiretroviral-naïve patients received either VIREAD + EMTRIVA administered in combination with efavirenz (N=257) or zidovudine/lamivudine administered in combination with efavirenz (N=254). Adverse reactions observed in this study were generally consistent with those seen in other studies in treatment-experienced or treatment-naïve patients receiving VIREAD and/or EMTRIVA (Table 2).
Table 2: Selected Treatment-Emergent Adverse Reactionsa
(Grades 2-4) Reported in ≥ 5% in Any Treatment Group in Study 934 (0-144 Weeks)
| FTC + TDF + EFVb | AZT/3TC + EFV | |
| N=257 | N=254 | |
| Gastrointestinal Disorder | ||
| Diarrhea | 9% | 5% |
| Nausea | 9% | 7% |
| Vomiting | 2% | 5% |
| General Disorders and Administration Site Condition | ||
| Fatigue | 9% | 8% |
| Infections and Infestations | ||
| Sinusitis | 8% | 4% |
| Upper respiratory tract infections | 8% | 5% |
| Nasopharyngitis | 5% | 3% |
| NervousSystem Disorders | ||
| Headache | 6% | 5% |
| Dizziness | 8% | 7% |
| PsychiatricDisorders | ||
| Depression | 9% | 7% |
| Insomnia | 5% | 7% |
| Skinand Subcutaneous Tissue Disorders | ||
| Rash Eventc | 7% | 9% |
| a.Frequencies of adverse reactions are based on
alltreatment-emergent adverse events, regardless of relationship to study
drug. b.From Weeks 96 to 144 of the study, patients received TRUVADA with efavirenzin place of VIREAD + EMTRIVA with efavirenz. c. Rash event includes rash, exfoliative rash, rashgeneralized, rash macular, rashmaculo-papular, rash pruritic, and rash vesicular. |
||
Laboratory Abnormalities: Laboratory abnormalities observed in this study were generally consistent with those seen in other studies of VIREAD and/or EMTRIVA (Table 3).
Table 3: Significant Laboratory Abnormalities Reported in
≥ 1% of Patients in Any Treatment Group in Study 934 (0-144 Weeks)
| FTC + TDF + EFVa | AZT/3TC + EFV | |
| N=257 | N=254 | |
| Any ≥ Grade 3 Laboratory Abnormality | 30% | 26% |
| Fasting Cholesterol (>240 mg/dL) | 22% | 24% |
| Creatine Kinase (M: >990 U/L) (F: >845 U/L) |
9% | 7% |
| Serum Amylase (>175 U/L) | 8% | 4% |
| Alkaline Phosphatase (>550 U/L) | 1% | 0% |
| AST (M: >180 U/L) (F: >170 U/L) |
3% | 3% |
| ALT (M: >215 U/L) (F: >170 U/L) |
2% | 3% |
| Hemoglobin (<8.0 mg/dL) | 0% | 4% |
| Hyperglycemia (>250 mg/dL) | 2% | 1% |
| Hematuria (>75 RBC/HPF) | 3% | 2% |
| Glycosuria ( ≥ 3+) | <1% | 1% |
| Neutrophils (<750/mm3) | 3% | 5% |
| Fasting Triglycerides (>750 mg/dL) | 4% | 2% |
| a. From Weeks 96 to 144 of the study, patients received TRUVADA with efavirenzin place of VIREAD + EMTRIVA with efavirenz. | ||
In addition to the events described above for Study 934, other adverse reactions that occurred in at least 5% of patients receiving EMTRIVA or VIREAD with other antiretroviral agents in clinical trials include anxiety, arthralgia, increased cough, dyspepsia, fever, myalgia, pain, abdominal pain, back pain, paresthesia, peripheral neuropathy (including peripheral neuritis and neuropathy), pneumonia, and rhinitis.
In addition to the laboratory abnormalities described above for Study 934, Grade 3/4 elevations of bilirubin ( > 2.5 x ULN), pancreatic amylase ( > 2.0 x ULN), serum glucose ( < 40 or > 250 mg/dL), and serum lipase ( > 2.0 x ULN) occurred in up to 3% of patients treated with EMTRIVA or VIREAD with other antiretroviral agents in clinical trials.
Postmarketing Experience
The following adverse reactions have been identified during postapproval use of VIREAD. 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
Metabolism and Nutrition Disorders
Hypophosphatemia, lactic acidosis
Respiratory, Thoracic, and Mediastinal Disorders
Dyspnea
Gastrointestinal Disorders
Abdominal pain, increased amylase, pancreatitis
Hepatobiliary Disorders
Increased liver enzymes (most commonly increased AST, ALT, Gamma GT), hepatitis
Skin and Subcutaneous Tissue Disorders
Rash
Musculoskeletal and Connective Tissue Disorders
Myopathy, osteomalacia (both associated with proximal renal tubulopathy)
Renal and Urinary Disorders
Renal insufficiency, renal failure, acute renal failure, Fanconi syndrome, proximal tubulopathy, proteinuria, increased creatinine, acute tubular necrosis, nephrogenic diabetes insipidus, polyuria, interstitial nephritis (including acute cases)
General Disorders and Administration Site Conditions
Asthenia
DRUG INTERACTIONS
No drug interaction studies have been conducted using TRUVADA tablets. Drug interaction studies have been conducted with emtricitabine and tenofovir disoproxil fumarate, the components of TRUVADA. This section describes clinically relevant drug interactions observed with emtricitabine and tenofovir disoproxil fumarate [See CLINICAL PHARMACOLOGY].
Didanosine
Coadministration of TRUVADA and didanosine should be undertaken with caution and patients receiving this combination should be monitored closely for didanosine-associated adverse reactions. Didanosine should be discontinued in patients who develop didanosine-associated adverse reactions.
When tenofovir disoproxil fumarate was administered with didanosine the Cmax and AUC of didanosine administered as either the buffered or enteric-coated formulation increased significantly [See CLINICAL PHARMACOLOGY]. The mechanism of this interaction is unknown. Higher didanosine concentrations could potentiate didanosine-associated adverse reactions, including pancreatitis, and neuropathy. Suppression of CD4+cell counts has been observed in patients receiving tenofovir DF with didanosine 400 mg daily.
In adults weighing > 60 kg, the didanosine dose should be reduced to 250 mg when it is coadministered with TRUVADA. Data are not available to recommend a dose adjustment of didanosine for patients weighing < 60 kg. When coadministered, TRUVADA and Videx EC may be taken under fasted conditions or with a light meal ( < 400 kcal, 20% fat). Coadministration of didanosine buffered tablet formulation with TRUVADA should be under fasted conditions.
Atazanavir
Atazanavir has been shown to increase tenofovir concentrations [See CLINICAL PHARMACOLOGY]. The mechanism of this interaction is unknown. Patients receiving atazanavir and TRUVADA should be monitored for TRUVADA-associated adverse reactions. TRUVADA should be discontinued in patients who develop TRUVADA-associated adverse reactions.
Tenofovir decreases the AUC and Cmin of atazanavir [See CLINICAL PHARMACOLOGY]. When coadministered with TRUVADA, it is recommended that atazanavir 300 mg is given with ritonavir 100 mg. Atazanavir without ritonavir should not be coadministered with TRUVADA.
Lopinavir/Ritonavir
Lopinavir/ritonavir has has been shown to increase tenofovir concentrations [See CLINICAL PHARMACOLOGY]. The mechanism of this interaction is unknown. Patients receiving lopinavir/ritonavir and TRUVADA should be monitored for TRUVADA-associated adverse reactions. TRUVADA should be discontinued in patients who develop TRUVADA-associated adverse reactions.
Drugs Affecting Renal Function
Emtricitabine and tenofovir are primarily excreted by the kidneys by a combination of glomerular filtration and active tubular secretion [See CLINICAL PHARMACOLOGY]. No drug-drug interactions due to competition for renal excretion have been observed; however, coadministration of TRUVADA with drugs that are eliminated by active tubular secretion may increase concentrations of emtricitabine, tenofovir, and/or the coadministered drug. Some examples include, but are not limited to acyclovir, adefovir dipivoxil, cidofovir, ganciclovir, valacyclovir, and valganciclovir. Drugs that decrease renal function may increase concentrations of emtricitabine and/or tenofovir.
PRECAUTIONS
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 alone or in combination with other antiretrovirals. A majority of these cases have been in women. Obesity and prolonged nucleoside exposure may be risk factors. Particular caution should be exercised when administering nucleoside analogs to any patient with known risk factors for liver disease; however, cases have also been reported in patients with no known risk factors. Treatment with TRUVADA 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).
Patients Coinfected with HIV-1 and HBV
It is recommended that all patients with HIV-1 be tested for the presence of chronic Hepatitis B virus (HBV) before initiating antiretroviral therapy. TRUVADA is not approved for the treatment of chronic HBV infection and the safety and efficacy of TRUVADA have not been established in patients coinfected with HBV and HIV-1. Severe acute exacerbations of Hepatitis B have been reported in patients who are coinfected with HBV and HIV-1 and have discontinued EMTRIVA or VIREAD. In some patients infected with HBV and treated with EMTRIVA, the exacerbations of Hepatitis B were associated with liver decompensation and liver failure. Hepatic function should be monitored closely with both clinical and laboratory follow up for at least several months in patients who are coinfected with HIV-1 and HBV and discontinue TRUVADA. If appropriate, initiation of anti-Hepatitis B therapy may be warranted.
New Onset or Worsening Renal Impairment
Emtricitabine and tenofovir are 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].
It is recommended that creatinine clearance be calculated in all patients prior to initiating therapy and as clinically appropriate during therapy with TRUVADA. Routine monitoring of calculated creatinine clearance and serum phosphorus should be performed in patients at risk for renal impairment.
Dosing interval adjustment of TRUVADA and close monitoring of renal function are recommended in all patients with creatinine clearance 30-49 mL/min, [See DOSAGE AND ADMINISTRATION]. No safety or efficacy data are available in patients with renal impairment who received TRUVADA using these dosing guidelines, so the potential benefit of TRUVADA therapy should be assessed against the potential risk of renal toxicity. TRUVADA should not be administered to patients with creatinine clearance < 30 mL/min or patients requiring hemodialysis.
TRUVADA should be avoided with concurrent or recent use of a nephrotoxic agent.
Coadministration with Related Products
TRUVADA is a fixed-dose combination of emtricitabine and tenofovir disoproxil fumarate. TRUVADA should not be coadministered with ATRIPLA, EMTRIVA, or VIREAD. Due to similarities between emtricitabine and lamivudine, TRUVADA should not be coadministered with other drugs containing lamivudine, including Combivir (lamivudine/zidovudine), Epivir or Epivir-HBV (lamivudine), Epzicom (abacavir sulfate/lamivudine), or Trizivir (abacavir sulfate/lamivudine/zidovudine).
Decreases in Bone Mineral Density
Bone mineral density monitoring should be considered for HIV-1 infected patients who have a history of pathologic bone fracture or are at risk for osteopenia. Although the effect of supplementation with calcium and vitamin D was not studied, such supplementation may be beneficial for all patients. If bone abnormalities are suspected then appropriate consultation should be obtained
Tenofovir Disoproxil Fumarate: In a 144-week study of treatment naive patients, decreases in bone mineral density (BMD) were seen at the lumbar spine and hip in both arms of the study. At Week 144, there was a significantly greater mean percentage decrease from baseline in BMD at the lumbar spine in patients receiving VIREAD + lamivudine + efavirenz compared with patients receiving stavudine + lamivudine + efavirenz. Changes in BMD at the hip were similar between the two treatment groups. In both groups, the majority of the reduction in BMD occurred in the first 24-48 weeks of the study and this reduction was sustained through 144 weeks. Twenty-eight percent of VIREAD-treated patients vs. 21% of the comparator patients 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 patients in the VIREAD group and 6 patients in the comparator group. Tenofovir disoproxil fumarate was associated with significant increases in biochemical markers of bone metabolism (serum bone-specific alkaline phosphatase, serum osteocalcin, serum C-telopeptide, and urinary N-telopeptide), suggesting increased bone turnover. Serum parathyroid hormone levels and 1,25 Vitamin D levels were also higher in patients receiving VIREAD. The effects of VIREAD-associated changes in BMD and biochemical markers on long-term bone health and future fracture risk are unknown. For additional information, please consult the VIREAD prescribing information.
Cases of osteomalacia (associated with proximal renal tubulopathy) have been reported in association with the use of VIREAD [See ADVERSE REACTIONS].
Fat Redistribution
Redistribution/accumulation of body fat including central obesity, dorsocervical fat enlargement (buffalo hump), peripheral wasting, facial wasting, breast enlargement, and "cushingoid appearance" have been observed in patients receiving antiretroviral therapy. The mechanism and long-term consequences of these events are currently unknown. A causal relationship has not been established.
Immune Reconstitution Syndrome
Immune reconstitution syndrome has been reported in patients treated with combination antiretroviral therapy, including EMTRIVA and VIREAD. During the initial phase of combination antiretroviral treatment, 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.
Patient Counseling Information
See FDA-approved patient labeling
Information for Patients
Patients should be advised that:
- TRUVADA is not a cure for HIV-1 infection and patients may continue to experience illnesses associated with HIV-1 infection, including opportunistic infections. Patients should remain under the care of a physician when using TRUVADA.
- The use of TRUVADA has not been shown to reduce the risk of transmission of HIV-1 to others through sexual contact or blood contamination.
- The long term effects of TRUVADA are unknown.
- TRUVADA tablets are for oral ingestion only.
- It is important to take TRUVADA with combination therapy on a regular dosing schedule to avoid missing doses.
- Lactic acidosis and severe hepatomegaly with steatosis, including fatal cases, have been reported. Treatment with TRUVADA should be suspended in any patients who develop clinical symptoms suggestive of lactic acidosis or pronounced hepatotoxicity (including nausea, vomiting, unusual or unexpected stomach discomfort, and weakness) [See WARNING and PRECAUTIONS].
- All patients with HIV-1 should be tested for Hepatitis B virus (HBV) before initiating antiretroviral therapy.
- Severe acute exacerbations of Hepatitis B have been reported in patients who are coinfected with HBV and HIV-1 and have discontinued EMTRIVA or VIREAD.
- Renal impairment, including cases of acute renal failure and Fanconi syndrome, has been reported in association with the use of VIREAD. TRUVADA should be avoided with concurrent or recent use of a nephrotoxic agent [See WARNING and PRECAUTIONS]. Dosing interval of TRUVADA may need adjustment in patients with renal impairment [See DOSAGE AND ADMINISTRATION].
- TRUVADA should not be coadministered with ATRIPLA, EMTRIVA, or VIREAD; or with drugs containing lamivudine, including Combivir (lamivudine/zidovudine), Epivir or Epivir-HBV (lamivudine), Epzicom (abacavir sulfate/lamivudine), or Trizivir (abacavir sulfate/lamivudine/zidovudine) [See WARNING and PRECAUTIONS].
- Decreases in bone mineral density have been observed with the use of VIREAD. Bone monitoring should be considered in patients who have a history of pathologic bone fracture or at risk for osteopenia [See WARNING and PRECAUTIONS].
Nonclinical Toxicology
Carcinogenesis, Mutagenesis, Impairment of Fertility
Emtricitabine: In long-term oral carcinogenicity studies of emtricitabine, no drug-related increases in tumor incidence were found in mice at doses up to 750 mg/kg/day (26 times the human systemic exposure at the therapeutic dose of 200 mg/day) or in rats at doses up to 600 mg/kg/day (31 times the human systemic exposure at the therapeutic dose).
Emtricitabine was not genotoxic in the reverse mutation bacterial test (Ames test), mouse lymphoma or mouse micronucleus assays.
Emtricitabine did not affect fertility in male rats at approximately 140-fold or in male and female mice at approximately 60-fold higher exposures (AUC) than in humans given the recommended 200 mg daily dose. Fertility was normal in the offspring of mice exposed daily from before birth (in utero) through sexual maturity at daily exposures (AUC) of approximately 60-fold higher than human exposures at the recommended 200 mg daily dose.
Tenofovir Disoproxil Fumarate: Long-term oral carcinogenicity studies of tenofovir disoproxil fumarate in mice and rats were carried out at exposures up to approximately 16 times (mice) and 5 times (rats) those observed in humans at the therapeutic dose for HIV-1 infection. At the high dose in female mice, liver adenomas were increased at exposures 16 times that in humans. In rats, the study was negative for carcinogenic findings at exposures up to 5 times that observed in humans at the therapeutic dose.
Tenofovir disoproxil fumarate was mutagenic in the in vitro mouse lymphoma assay and negative in an in vitro bacterial mutagenicity test (Ames test). In an in vivo mouse micronucleus assay, tenofovir disoproxil fumarate was negative when administered to male mice.
There were no effects on fertility, mating performance or early embryonic development when tenofovir disoproxil fumarate was administered to male rats at a dose equivalent to 10 times the human dose based on body surface area comparisons for 28 days prior to mating and to female rats for 15 days prior to mating through day seven of gestation. There was, however, an alteration of the estrous cycle in female rats.
Use In Specific Populations
Pregnancy
Pregnancy Category B
Emtricitabine: The incidence of fetal variations and malformations was not increased in embryofetal toxicity studies performed with emtricitabine in mice at exposures (AUC) approximately 60-fold higher and in rabbits at approximately 120-fold higher than human exposures at the recommended daily dose.
Tenofovir Disoproxil Fumarate: Reproduction studies have been performed in rats and rabbits at doses up to 14 and 19 times the human dose based on body surface area comparisons and revealed no evidence of impaired fertility or harm to the fetus due to tenofovir.
There are, however, no adequate and well-controlled studies in pregnant women. Because animal reproduction studies are not always predictive of human response, TRUVADA should be used during pregnancy only if clearly needed.
Antiretroviral Pregnancy Registry: To monitor fetal outcomes of pregnant women exposed to TRUVADA, an Antiretroviral Pregnancy Registry has been established. Healthcare providers are encouraged to register patients by calling 1-800-258-4263.
Nursing Mothers
Nursing Mothers: The Centers for Disease Control and Prevention recommend that HIV-1-infected mothers not breast-feed their infants to avoid risking postnatal transmission of HIV-1. Studies in rats have demonstrated that tenofovir is secreted in milk. It is not known whether tenofovir is excreted in human milk. It is not known whether emtricitabine is excreted in human milk. Because of both the potential for HIV-1 transmission and the potential for serious adverse reactions in nursing infants, mothers should be instructed not to breast-feed if they are receiving TRUVADA.
Pediatric Use
Truvada is not recommended for patients less than 18 years of age because it is a fixed-dose combination tablet containing a component, VIREAD, for which safety and efficacy have not been established in this age group.
Geriatric Use
Clinical studies of EMTRIVA or VIREAD did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects. In general, dose selection for the elderly patients should be cautious, keeping in mind the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy.
Patients with Impaired Renal Function
It is recommended that the dosing interval for TRUVADA be modified in patients with creatinine clearance 30-49 mL/min. TRUVADA should not be used in patients with creatinine clearance < 30 mL/min and in patients with end-stage renal disease requiring dialysis [See DOSAGE AND ADMINISTRATION].
OVERDOSE
If overdose occurs the patient must be monitored for evidence of toxicity, and standard supportive treatment applied as necessary.
Emtricitabine: Limited clinical experience is available at doses higher than the therapeutic dose of EMTRIVA. In one clinical pharmacology study single doses of emtricitabine 1200 mg were administered to 11 patients. No severe adverse reactions were reported.
Hemodialysis treatment removes approximately 30% of the emtricitabine dose over a 3-hour dialysis period starting within 1.5 hours of emtricitabine dosing (blood flow rate of 400 mL/min and a dialysate flow rate of 600 mL/min). It is not known whether emtricitabine can be removed by peritoneal dialysis.
Tenofovir Disoproxil Fumarate: Limited clinical experience at doses higher than the therapeutic dose of VIREAD 300 mg is available. In one study, 600 mg tenofovir disoproxil fumarate was administered to 8 patients orally for 28 days, and no severe adverse reactions were reported. The effects of higher doses are not known.
Tenofovir is efficiently removed by hemodialysis with an extraction coefficient of approximately 54%. Following a single 300 mg dose of VIREAD, a four-hour hemodialysis session removed approximately 10% of the administered tenofovir dose.
CONTRAINDICATIONS
TRUVADA is contraindicated in patients with previously demonstrated hypersensitivity to any of the components of the product.
CLINICAL PHARMACOLOGY
For additional information on Mechanism of Action, Antiviral Activity, Resistance and Cross Resistance, please consult the EMTRIVA and VIREAD prescribing information.
Mechanism of Action
TRUVADA is a fixed-dose combination of antiviral drugs emtricitabine and tenofovir disoproxil fumarate. [See CLINICAL PHARMACOLOGY].
Pharmacokinetics
TRUVADA: One TRUVADA tablet was bioequivalent to one EMTRIVA capsule (200 mg) plus one VIREAD tablet (300 mg) following single-dose administration to fasting healthy subjects (N=39).
Emtricitabine: The pharmacokinetic properties of emtricitabine are summarized in Table 4. Following oral administration of EMTRIVA, emtricitabine is rapidly absorbed with peak plasma concentrations occurring at 1-2 hours post-dose. In vitro binding of emtricitabine to human plasma proteins is < 4% and is independent of concentration over the range of 0.02-200 µg/mL. Following administration of radiolabelled emtricitabine, approximately 86% is recovered in the urine and 13% is recovered as metabolites. The metabolites of emtricitabine include 3' -sulfoxide diastereomers and their glucuronic acid conjugate. Emtricitabine is eliminated by a combination of glomerular filtration and active tubular secretion. Following a single oral dose of EMTRIVA, the plasma emtricitabine half-life is approximately 10 hours.
Tenofovir Disoproxil Fumarate: The pharmacokinetic properties of tenofovir disoproxil fumarate are summarized in Table 4. Following oral administration of VIREAD, maximum tenofovir serum concentrations are achieved in 1.0 ± 0.4 hour. In vitro binding of tenofovir to human plasma proteins is < 0.7% and is independent of concentration over the range of 0.01-25 µg/mL. Approximately 70-80% of the intravenous dose of tenofovir is recovered as unchanged drug in the urine. Tenofovir is eliminated by a combination of glomerular filtration and active tubular secretion. Following a single oral dose of VIREAD, the terminal elimination half-life of tenofovir is approximately 17 hours.
Table 4: Single Dose Pharmacokinetic Parameters for Emtricitabine
and Tenofovir in Adultsa
| Emtricitabine | Tenofovir | |
| Fasted Oral Bioavailabilityb (%) | 92 (83.1-106.4) | 25 (NC-45.0) |
| Plasma Terminal Elimination Half-Lifeb (hr) | 10 (7.4-18.0) | 17 (12.0-25.7) |
| Cmaxc (µg/mL) | 1.8 ± 0.72d | 0.30 ± 0.09 |
| AUCc (µg·hr/mL) | 10.0 ± 3.12d | 2.29 ± 0.69 |
| CL/Fc (mL/min) | 302 ± 94 | 1043 ± 115 |
| CLrenalc (mL/min) | 213 ± 89 | 243 ± 33 |
| a. NC = Not calculated bMedian (range) c Mean (± SD) d Data presented as steady state values. |
||
Effects of Food on Oral Absorption
TRUVADA may be administered with or without food. Administration of TRUVADA following a high fat meal (784 kcal; 49 grams of fat) or a light meal (373 kcal; 8 grams of fat) delayed the time of tenofovir Cmax by approximately 0.75 hour. The mean increases in tenofovir AUC and Cmax were approximately 35% and 15%, respectively, when administered with a high fat or light meal, compared to administration in the fasted state. In previous safety and efficacy studies, VIREAD (tenofovir) was taken under fed conditions. Emtricitabine systemic exposures (AUC and Cmax) were unaffected when TRUVADA was administered with either a high fat or a light meal.
Special Populations
Race
Emtricitabine: No pharmacokinetic differences due to race have been identified following the administration of EMTRIVA.
Tenofovir Disoproxil Fumarate: There were insufficient numbers from racial and ethnic groups other than Caucasian to adequately determine potential pharmacokinetic differences among these populations following the administration of VIREAD.
Gender
Emtricitabine and Tenofovir Disoproxil Fumarate: Emtricitabine and tenofovir pharmacokinetics are similar in male and female patients.
Pediatric and Geriatric Patients
Pharmacokinetic studies of tenofovir have not been performed in pediatric patients ( < 18 years). Pharmacokinetics of emtricitabine and tenofovir have not been fully evaluated in the elderly ( > 65 years).
Patients with Impaired Renal Function
The pharmacokinetics of emtricitabine and tenofovir are altered in patients with renal impairment [See WARNINGS and PRECAUTIONS]. In patients with creatinine clearance < 50 mL/min, Cmax, and AUC0-&inifn; of emtricitabine and tenofovir were increased. It is recommended that the dosing interval for TRUVADA be modified in patients with creatinine clearance 30-49 mL/min. TRUVADA should not be used in patients with creatinine clearance < 30 mL/min and in patients with end-stage renal disease requiring dialysis [See DOSAGE AND ADMINISTRATION].
Patients with Hepatic Impairment
The pharmacokinetics of tenofovir following a 300 mg dose of VIREAD have been studied in non-HIV infected patients with moderate to severe hepatic impairment. There were no substantial alterations in tenofovir pharmacokinetics in patients with hepatic impairment compared with unimpaired patients. The pharmacokinetics of TRUVADA or emtricitabine have not been studied in patients with hepatic impairment; however, emtricitabine is not significantly metabolized by liver enzymes, so the impact of liver impairment should be limited.
Assessment of Drug Interactions
The steady state pharmacokinetics of emtricitabine and tenofovir were unaffected when emtricitabine and tenofovir disoproxil fumarate were administered together versus each agent dosed alone.
In vitro and clinical pharmacokinetic drug-drug interaction studies have shown that the potential for CYP mediated interactions involving emtricitabine and tenofovir with other medicinal products is low.
No clinically significant drug interactions have been observed between emtricitabine and famciclovir, indinavir, stavudine, tenofovir disoproxil fumarate, and zidovudine (see Tables 5 and 6). Similarly, no clinically significant drug interactions have been observed between tenofovir disoproxil fumarate and abacavir, adefovir dipivoxil, efavirenz, emtricitabine, indinavir, lamivudine, lopinavir/ritonavir, methadone, nelfinavir, oral contraceptives, ribavirin, and saquinavir/ritonavir in studies conducted in healthy volunteers (see Tables 7 and 8).
Table 5: Drug Interactions: Changes in Pharmacokinetic Parameters
for Emtricitabine in the Presence of the Coadministered Druga
| Coadministered Drug | Dose of Coadministered Drug (mg) | Emtricitabine Dose (mg) | N | % Change of Emtricitabine Pharmacokinetic Parametersb (90%CI) | ||
| Cmax | AUC | Cmin | ||||
| Tenofovir DF | 300 once daily × 7 days | 200 once daily × 7 days | 17 | ⇔ | ⇔ | ↑20 (↑12 to ↑29) |
| Zidovudine | 300 twice daily × 7 days | 200 once daily × 7 days | 27 | ⇔ | ⇔ | ⇔ |
| Indinavir | 800 × 1 | 200 × 1 | 12 | ⇔ | ⇔ | NA |
| Famciclovir | 500 × 1 | 200 × 1 | 12 | ⇔ | ⇔ | NA |
| Stavudine | 40 × 1 | 200 × 1 | 6 | ⇔ | ⇔ | NA |
| a. All interaction studies conducted in healthy
volunteers. b↑= Increase; ↓= Decrease; ⇔= NoEffect; NA = Not Applicable |
||||||
Table 6: Drug Interactions: Changes in Pharmacokinetic Parameters
for Coadministered Drug in the Presence of Emtricitabinea
| Coadministered Drug | Dose of Coadministered Drug (mg) | Emtricitabine Dose (mg) | N | % Change of Coadministered Drug Pharmacokinetic Parametersb (90%CI) | ||
| Cmax | AUC | Cmin | ||||
| Tenofovir DF | 300 once daily × 7 days | 200 once daily × 7 days | 17 | ⇔ | ⇔ | ⇔ |
| Zidovudine | 300 twice daily × 7 days | 200 once daily × 7 days | 27 | ↑17 (↑0 to ↑38) |
↑13 (↑5 to ↑20) |
⇔ |
| Indinavir | 800 × 1 | 200 × 1 | 12 | ⇔ | ⇔ | NA |
| Famciclovir | 500 × 1 | 200 × 1 | 12 | ⇔ | ⇔ | NA |
| Stavudine | 40 × 1 | 200 × 1 | 6 | ⇔ | ⇔ | NA |
| a.All interaction studies conducted in healthy
volunteers. b.↑= Increase; ↓= Decrease; ⇔ = No Effect; NA = Not Applicable |
||||||
Table 7: 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 Parametersb (90% CI) | ||
| Cmax | AUC | Cmin | |||
| Abacavir | 300 once | 8 | ⇔ | ⇔ | NC |
| Adefovir dipivoxil | 10 once | 22 | ⇔ | ⇔ | NC |
| Atazanavirc | 400 once daily × 14 days | 33 | ↑14 (↑8 to ↑20) |
↑24 (↑21 to ↑28) |
↑22 (↑15 to ↑30) |
| Didanosine (enteric-coated) | 400 once | 25 | ⇔ | ⇔ | ⇔ |
| Didanosine (buffered) | 250 or 400 once daily × 7 days | 14 | ⇔ | ⇔ | ⇔ |
| Efavirenz | 600 once daily × 14 days | 29 | ⇔ | ⇔ | ⇔ |
| Emtricitabine | 200 once daily × 7 days | 17 | ⇔ | ⇔ | ⇔ |
| Indinavir | 800 three timesdaily × 7 days | 13 | ↑14 (↓3 to ↑33) |
⇔ | ⇔ |
| Lamivudine | 150 twice daily × 7 days | 15 | ⇔ | ⇔ | ⇔ |
| Lopinavir/Ritonavir | 400/100 twicedaily × 14 days | 24 | ⇔ | ↑32 (↑25 to ↑38) |
↑51 (↑37 to ↑66) |
| Nelfinavir | 1250 twice daily × 14 days | 29 | ⇔ | ⇔ | ⇔ |
| Saquinavir/Ritonavir | 1000/100 twicedaily × 14 days | 35 | ⇔ | ⇔ | ↑23 (↑16 to ↑30) |
| a.Patients received VIREAD 300 mg once daily. b Increase = ↑;Decrease = ↓; No Effect =⇔; NC= Not Calculated c.Reyataz Prescribing Information |
|||||
Table 8: Drug Interactions: Changes in Pharmacokinetic Parameters
for Coadministered Drug in the Presence of Tenofovir
| Coadministered Drug | Dose of Coadministered Drug (mg) | N | % Change of Coadministered Drug Pharmacokinetic Parametersa(90% CI) | ||
| Cmax | AUC | Cmin | |||
| Abacavir | 300 once | 8 | ↑12 (↓1 to ↑26) |
⇔ | NA |
| Adefovir dipivoxil | 10 once | 22 | ⇔ | ⇔ | NA |
| Atazanavirb | 400 once daily × 14 days | 34 | ↓21 (↓27 to ↓14) |
↓25 (↓30 to ↓19) |
↓40 (↓48 to ↓32) |
| Atazanavirb | Atazanavir/ Ritonavir 300/100 once daily × 42 days | 10 | ↓28 (↓50 to ↓5) |
↓25c (↓42 to ↓3) |
↓23c (↓46 to ↓10) |
| Efavirenz | 600 once daily × 14 days | 30 | ⇔ | ⇔ | ⇔ |
| Emtricitabine | 200 once daily × 7 days | 17 | ⇔ | ⇔ | ↑20 (↑12 to ↑29) |
| Indinavir | 800 three times daily × 7 days | 12 | ↓11 (↓30 to ↑12) |
⇔ | ⇔ |
| Lamivudine | 150 twice daily × 7 days | 15 | ↓24 (↓34 to ↓12) |
⇔ | ⇔ |
| Lopinavir Ritonavir | Lopinavir/Ritonavir 400/100 twice daily × 14 days | 24 | ⇔ | ⇔ | ⇔ |
| ⇔ | ⇔ | ⇔ | |||
| Methadoned | 40-110 once daily × 14 dayse | 13 | ⇔ | ⇔ | ⇔ |
| Nelfinavir M8 metabolite | 1250 twice daily × 14 days | 29 | ⇔ | ⇔ | ⇔ |
| ⇔ | ⇔ | ⇔ | |||
| Oral Contraceptivesf | Ethinyl Estradiol/ Norgestimate (Ortho-Tricyclen) Once daily × 7 days | 20 | ⇔ | ⇔ | ⇔ |
| Ribavirin | 600 once | 22 | ⇔ | ⇔ | NA |
| Saquinavir Ritonavir |
Saquinavir/Ritonavir 1000/100 twice daily × 14 days | 32 | ↑22 (↑6 to ↑41) |
↑29g (↑12 to ↑48) |
↑47g (↑23 to ↑76) |
| ⇔ | ⇔ | ↑23 (↑3 to ↑46) |
|||
| a. Increase = ↑; Decrease = ↓; No Effect
= ⇔; NA = Not Applicable b. Reyataz Prescribing Information c. In HIV-infected patients, addition of tenofovir DF to atazanavir 300 mg plus ritonavir 100 mg, resulted in AUC and Cmin values of atazanavir that were 2.3 and 4-fold higher than the respective values observed for atazanavir 400 mg when given alone. d. R-(active), S- and total methadone exposures were equivalent when dosed alone or with VIREAD. e. Individual subjects were maintained on their stable methadone dose. No pharmacodynamic alterations (opiate toxicity or withdrawal signs or symptoms) were reported. f. Ethinyl estradiol and 17-deacetyl norgestimate (pharmacologically active metabolite) exposures were equivalent when dosed alone or with VIREAD. g. Increases in AUC and Cmin are not expected to be clinically relevant; hence no dose adjustments are required when tenofovir DF and ritonavir-boosted saquinavir are coadministered. |
|||||
Following multiple dosing to HIV-negative subjects receiving either chronic methadone maintenance therapy or oral contraceptives, or single doses of ribavirin, steady state tenofovir pharmacokinetics were similar to those observed in previous studies, indicating lack of clinically significant drug interactions between these agents and VIREAD.
Coadministration of tenofovir disoproxil fumarate with didanosine results in changes in the pharmacokinetics of didanosine that may be of clinical significance. Table 9 summarizes the effects of tenofovir disoproxil fumarate on the pharmacokinetics of didanosine. Concomitant dosing of tenofovir disoproxil fumarate with didanosine buffered tablets or enteric-coated capsules significantly increases the Cmax and AUC of didanosine. When didanosine 250 mg enteric-coated capsules were administered with tenofovir disoproxil fumarate, systemic exposures of didanosine were similar to those seen with the 400 mg enteric-coated capsules alone under fasted conditions. The mechanism of this interaction is unknown. See DRUG INTERACTIONS regarding use of didanosine with VIREAD.
Table 9: Drug Interactions: Pharmacokinetic Parameters for
Didanosine in the Presence of VIREAD
| Didanosinea Dose (mg)/Method of Administrationa | VIREAD Method of Administrationa | N | % Difference (90% CI) vs. Didanosine 400 mg Alone, Fastedb | |
| Cmax | AUC | |||
| Buffered tablets | ||||
| 400 once dailyc x 7 days | Fasted 1 hour after didanosine | 14 | ↑28 (↑11 to ↑48) |
↑44 (↑31 to ↑59) |
| Enteric coated capsules | ||||
| 400 once, fasted | With food, 2 hours after didanosine | 26 | ↑48 (↑25 to ↑76) |
↑48 (↑31 to ↑67) |
| 400 once, with food | Simultaneously with didanosine | 26 | ↑64 (↑41 to ↑89) |
↑60 (↑44 to ↑79) |
| 250 once, fasted | With food, 2 hours after didanosine | 28 | ↓10 (↓22 to ↑3) |
⇔ |
| 250 once, fasted | Simultaneously with didanosine | 28 | ⇔ | ↑14 (0 to ↑31) |
| 250 once, with food | Simultaneously with didanosine | 28 | ↓29 (↓39 to ↓18) |
↓11 (↓23 to ↑2) |
| a.Administration with food was with a light meal
(~373 kcal, 20% fat). b. Increase =↑; Decrease =↓ ; No Effect =⇔ c.Includes 4 subjects weighing <60 kg receiving ddI 250 mg. |
||||
Microbiology
Mechanism of Action
Emtricitabine: Emtricitabine, a synthetic nucleoside analog of cytidine, is phosphorylated by cellular enzymes to form emtricitabine 5'-triphosphate. Emtricitabine 5'-triphosphate inhibits the activity of the HIV-1 reverse transcriptase (RT) by competing with the natural substrate deoxycytidine 5'-triphosphate and by being incorporated into nascent viral DNA which results in chain termination. Emtricitabine 5' -triphosphate is a weak inhibitor of mammalian DNA polymerase α, &bets;, ε and mitochondrial DNA polymerase γ .
Tenofovir Disoproxil Fumarate: Tenofovir disoproxil fumarate is an acyclic nucleoside phosphonate diester analog of adenosine monophosphate. Tenofovir disoproxil fumarate requires initial diester hydrolysis for conversion to tenofovir and subsequent phosphorylations by cellular enzymes to form tenofovir diphosphate. Tenofovir diphosphate inhibits the activity of HIV-1 RT by competing with the natural substrate deoxyadenosine 5' -triphosphate and, after incorporation into DNA, by DNA chain termination. Tenofovir diphosphate is a weak inhibitor of mammalian DNA polymerases α, β, and mitochondrial DNA polymerase γ .
Antiviral Activity
Emtricitabine and Tenofovir Disoproxil Fumarate: In combination studies evaluating the cell culture antiviral activity of emtricitabine and tenofovir together, synergistic antiviral effects were observed.
Emtricitabine: The antiviral activity of emtricitabine against laboratory and clinical isolates of HIV-1 was assessed in lymphoblastoid cell lines, the MAGI-CCR5 cell line, and peripheral blood mononuclear cells. The 50% effective concentration (EC50) values
for emtricitabine were in the range of 0.0013-0.64 µM (0.0003-0.158 µg/mL). In drug combination studies of emtricitabine with nucleoside reverse transcriptase inhibitors (abacavir, lamivudine, stavudine, zalcitabine, zidovudine), non-nucleoside reverse transcriptase inhibitors (delavirdine, efavirenz, nevirapine), and protease inhibitors (amprenavir, nelfinavir, ritonavir, saquinavir), additive to synergistic effects were observed. Emtricitabine displayed antiviral activity in cell culture against HIV-1 clades A, B, C, D, E, F, and G (EC50 values ranged from 0.007-0.075 µM) and showed strain specific activity against HIV-2 (EC50 values ranged from 0.007-1.5 µM).
Tenofovir Disoproxil Fumarate: The antiviral activity of tenofovir against laboratory and clinical isolates of HIV-1 was assessed in lymphoblastoid cell lines, primary monocyte/macrophage cells and peripheral blood lymphocytes. The EC50 values for tenofovir were in the range of 0.04-8.5 µM. In drug combination studies of tenofovir with nucleoside reverse transcriptase inhibitors (abacavir, didanosine, lamivudine, stavudine, zalcitabine, zidovudine), non-nucleoside reverse transcriptase inhibitors (delavirdine, efavirenz, nevirapine), and protease inhibitors (amprenavir, indinavir, nelfinavir, ritonavir, saquinavir), additive to synergistic effects were observed. Tenofovir displayed antiviral activity in cell culture against HIV-1 clades A, B, C, D, E, F, G and O (EC50 values ranged from 0.5-2.2 µM) and showed strain specific activity against HIV-2 (EC50 values ranged from 1.6 µM to 5.5 µM).
Resistance
Emtricitabine and Tenofovir Disoproxil Fumarate: HIV-1 isolates with reduced susceptibility to the combination of emtricitabine and tenofovir have been selected in cell culture. Genotypic analysis of these isolates identified the M184V/I and/or K65R amino acid substitutions in the viral RT. In a clinical study of treatment-naïve patients [Study 934, see Clinical Studies], resistance analysis was performed on HIV-1 isolates from all confirmed virologic failure patients with > 400 copies/mL of HIV-1 RNA at Week 144 or early discontinuation. Development of efavirenz resistance-associated substitutions occurred most frequently and was similar between the treatment arms. The M184V amino acid substitution, associated with resistance to EMTRIVA and lamivudine, was observed in 2/19 analyzed patient isolates in the EMTRIVA + VIREAD group and in 10/29 analyzed patient isolates in the zidovudine/lamivudine group. Through 144 weeks of Study 934, no patients have developed a detectable K65R substitution in their HIV-1 as analyzed through standard genotypic analysis.
Emtricitabine: Emtricitabine-resistant isolates of HIV-1 have been selected in cell culture and in vivo. Genotypic analysis of these isolates showed that the reduced susceptibility to emtricitabine was associated with a substitution in the HIV-1 RT gene at codon 184 which resulted in an amino acid substitution of methionine by valine or isoleucine (M184V/I).
Tenofovir Disoproxil Fumarate: HIV-1 isolates with reduced susceptibility to tenofovir have been selected in cell culture. These viruses expressed a K65R substitution in RT and showed a 2-4 fold reduction in susceptibility to tenofovir. In treatment-naïve patients, isolates from 8/47 (17%) analyzed patients developed the K65R substitution in the VIREAD arm through 144 weeks; 7 occurred in the first 48 weeks of treatment and 1 at Week 96. In treatment-experienced patients, 14/304 (5%) isolates from patients failing VIREAD through Week 96 showed > 1.4 fold (median 2.7) reduced susceptibility to tenofovir. Genotypic analysis of the resistant isolates showed a substitution in the HIV-1 RT gene resulting in the K65R amino acid substitution.
Cross Resistance
Emtricitabine and Tenofovir Disoproxil Fumarate: Cross-resistance among certain nucleoside reverse transcriptase inhibitors (NRTIs) has been recognized. The M184V/I and/or K65R substitutions selected in cell culture by the combination of emtricitabine and tenofovir are also observed in some HIV-1 isolates from subjects failing treatment with tenofovir in combination with either lamivudine or emtricitabine, and either abacavir or didanosine. Therefore, cross-resistance among these drugs may occur in patients whose virus harbors either or both of these amino acid substitutions.
Emtricitabine: Emtricitabine-resistant isolates (M184V/I) were cross-resistant to lamivudine and zalcitabine but retained susceptibility in cell culture to didanosine, stavudine, tenofovir, zidovudine, and NNRTIs (delavirdine, efavirenz, and nevirapine). HIV-1 isolates containing the K65R substitution, selected in vivo by abacavir, didanosine, tenofovir, and zalcitabine, demonstrated reduced susceptibility to inhibition by emtricitabine. Viruses harboring substitutions conferring reduced susceptibility to stavudine and zidovudine (M41L, D67N, K70R, L210W, T215Y/F, K219Q/E), or didanosine (L74V) remained sensitive to emtricitabine. HIV-1 containing the K103N substitution associated with resistance to NNRTIs was susceptible to emtricitabine.
Tenofovir Disoproxil Fumarate: HIV-1 isolates from patients (N=20) whose HIV-1 expressed a mean of 3 zidovudine-associated RT amino acid substitutions (M41L, D67N, K70R, L210W, T215Y/F, or K219Q/E/N) showed a 3.1-fold decrease in the susceptibility to tenofovir. Multinucleoside resistant HIV-1 with a T69S double insertion substitution in the RT showed reduced susceptibility to tenofovir.
Animal Toxicology and/or Pharmacology
Tenofovir and tenofovir disoproxil fumarate administered in toxicology studies to rats, dogs and monkeys at exposures (based on AUCs) greater than or equal to 6-fold those observed in humans caused bone toxicity. In monkeys the bone toxicity was diagnosed as osteomalacia. Osteomalacia observed in monkeys appeared to be reversible upon dose reduction or discontinuation of tenofovir. In rats and dogs, the bone toxicity manifested as reduced bone mineral density. The mechanism(s) underlying bone toxicity is unknown.
Evidence of renal toxicity was noted in 4 animal species. Increases in serum creatinine, BUN, glycosuria, proteinuria, phosphaturia, and/or calciuria and decreases in serum phosphate were observed to varying degrees in these animals. These toxicities were noted at exposures (based on AUCs) 2-20 times higher than those observed in humans. The relationship of the renal abnormalities, particularly the phosphaturia, to the bone toxicity is not known.
Clinical Studies
Clinical Study 934 supports the use of TRUVADA tablets for the treatment of HIV-1 infection. Additional data in support of the use of TRUVADA are derived from Study 903, in which lamivudine and tenofovir disoproxil fumarate (tenofovir DF) were used in combination in treatment-naïve adults, and clinical Study 303 in which emtricitabine and lamivudine demonstrated comparable efficacy, safety and resistance patterns as part of multidrug regimens. For additional information about these studies, please consult the prescribing information for tenofovir DF and emtricitabine.
Study 934
Data through 144 weeks are reported for Study 934, a randomized, open-label, active-controlled multicenter study comparing emtricitabine + tenofovir DF administered in combination with efavirenz versus zidovudine/lamivudine fixed-dose combination administered in combination with efavirenz in 511 antiretroviral-naïve patients. From Weeks 96 to 144 of the study, patients received TRUVADA with efavirenz in place of emtricitabine + tenofovir DF with efavirenz. Patients had a mean age of 38 years (range 18-80), 86% were male, 59% were Caucasian and 23% were Black. The mean baseline CD4+ cell count was 245 cells/mm3 (range 2-1191) and median baseline plasma HIV-1 RNA was 5.01 log10 copies/mL (range 3.56-6.54). Patients were stratified by baseline CD4+ cell count ( < or 200 cells/mm3); 41% had CD4+ cell counts < 200 cells/mm3 and 51% of patients had baseline viral loads > 100,000 copies/mL. Treatment outcomes through 48 and 144 weeks for those patients who did not have efavirenz resistance at baseline are presented in Table 10.
Table 10: Outcomes of Randomized Treatment at Week 48 and
144 (Study 934)
| Outcomes | At Week 48 | At Week 144 | ||
| FTC + TDF + EFV (N=244) |
AZT/3TC + EFV (N=243) |
FTC + TDF + EFV (N=227)a |
AZT/3TC + EFV (N=229)a |
|
| Responderb | 84% | 73% | 71% | 58% |
| Virologic failurec | 2% | 4% | 3% | 6% |
| Rebound | 1% | 3% | 2% | 5% |
| Never suppressed | 0% | 0% | 0% | 0% |
| Change in antiretroviral regimen | 1% | 1% | 1% | 1% |
| Death | <1% | 1% | 1% | 1% |
| Discontinued due to adverse event | 4% | 9% | 5% | 12% |
| Discontinued for other reasonsd | 10% | 14% | 20% | 22% |
| a. Patients who were responders at Week48 or Week
96(HIV-1 RNA < 400 copies/mL) but didnot consent to continue study after
Week 48 or Week 96 were excluded from analysis. b.Patients achieved and maintained confirmed HIV-1 RNA < 400copies/mL through Weeks48 and 144. c. Includes confirmed viral rebound and failure to achieve confirmed <400 copies/mL through Weeks 48 and 144. d.Includes lost to follow-up, patient with drawal, noncompliance, protocol violation and other reasons. |
||||
Through Week 48, 84% and 73% of patients in the emtricitabine + tenofovir DF group and the zidovudine/lamivudine group, respectively, achieved and maintained HIV-1 RNA < 400 copies/mL (71% and 58% through Week 144). The difference in the proportion of patients who achieved and maintained HIV-1 RNA < 400 copies/mL through 48 weeks largely results from the higher number of discontinuations due to adverse events and other reasons in the zidovudine/lamivudine group in this open-label study. In addition, 80% and 70% of patients in the emtricitabine + tenofovir DF group and the zidovudine/lamivudine group, respectively, achieved and maintained HIV-1 RNA < 50 copies/mL through Week 48 (64% and 56% through Week 144). The mean increase from baseline in CD4+ cell count was 190 cells/mm3 in the emtricitabine + tenofovir DF group and 158 cells/mm3 in the zidovudine/lamivudine group at Week 48 (312 and 271 cells/mm3 at Week 144). Through 48 weeks, 7 patients in the emtricitabine + tenofovir DF group and 5 patients in the zidovudine/lamivudine group experienced a new CDC Class C event (10 and 6 patients through 144 weeks).
PATIENT INFORMATION
TRUVADA®
(tru-VAH-dah) tablets
Generic name: emtricitabine and tenofovir disoproxil fumarate (em tri SIT uh bean and te NOE' fo veer dye soe PROX il FYOU mar ate)
Read the Patient Information that comes with TRUVADA before you start taking it and each time you get a refill. There may be new information. This information does not take the place of talking to your healthcare provider about your medical condition or treatment. You should stay under a healthcare provider's care when taking TRUVADA. Do not change or stop your medicine without first talking with your healthcare provider. Talk to your healthcare provider or pharmacist if you have any questions about TRUVADA.
What is the most important information I should know about TRUVADA?
- Some people who have taken medicine like TRUVADA (nucleoside analogs) have developed a serious condition called lactic acidosis(build up of an acid in the blood). Lactic acidosis can be a medical emergency and may need to be treated in the hospital. Call your healthcare provider right away if you get the following signs or symptoms of lactic acidosis.
- Some people who have taken medicines like TRUVADA have developed serious liver problems called hepatotoxicity, with liver enlargement (hepatomegaly) and fat in the liver (steatosis). Call your healthcare provider right away if you get the following signs or symptoms of liver problems.
- You may be more likely to get lactic acidosis or liver problems if you are female, very overweight (obese), or have been taking nucleoside analog medicines, like TRUVADA, for a long time.
- If you are also infected with the Hepatitis B Virus (HBV), you need close medical follow-up for several months after stopping treatment with TRUVADA. Follow-up includes medical exams and blood tests to check for HBV that could be getting worse. Patients with Hepatitis B Virus infection, who take TRUVADA and then stop it, may get "flare-ups" of their hepatitis. A "flare-up" is when the disease suddenly returns in a worse way than before.
What is TRUVADA?
TRUVADA is a type of medicine called an HIV-1 (human immunodeficiency virus) nucleoside analog reverse transcriptase inhibitor (NRTI). TRUVADA contains 2 medicines, EMTRIVA® (emtricitabine) and VIREAD® (tenofovir disoproxil fumarate, or tenofovir DF) combined in one pill. TRUVADA is always used with other anti-HIV-1 medicines to treat people with HIV-1 infection. TRUVADA is for adults age 18 and older. TRUVADA has not been studied in children under age 18 or adults over age 65.
HIV infection destroys CD4+ T cells, which are important to the immune system. The immune system helps fight infection. After a large number of T cells are destroyed, acquired immune deficiency syndrome (AIDS) develops. TRUVADA helps block HIV-1 reverse transcriptase, a chemical in your body (enzyme) that is needed for HIV-1 to multiply. TRUVADA lowers the amount of HIV-1 in the blood (viral load). TRUVADA may also help to increase the number of T cells (CD4+ cells). Lowering the amount of HIV-1 in the blood lowers the chance of death or infections that happen when your immune system is weak (opportunistic infections).
TRUVADA does not cure HIV-1 infection or AIDS. The long-term effects of TRUVADA are not known at this time. People taking TRUVADA may still get opportunistic infections or other conditions that happen with HIV-1 infection. Opportunistic infections are infections that develop because the immune system is weak. Some of these conditions are pneumonia, herpes virus infections, and Mycobacterium avium complex (MAC) infection. It is very important that you see your healthcare provider regularly while taking TRUVADA.
TRUVADA does not lower your chance of passing HIV-1 to other people through sexual contact, sharing needles, or being exposed to your blood. For your health and the health of others, it is important to always practice safer sex by using a latex or polyurethane condom or other barrier to lower the chance of sexual contact with semen, vaginal secretions, or blood. Never use or share dirty needles.
Who should not take TRUVADA?
- Do not take TRUVADA if you are allergic to TRUVADA or any of its ingredients. The active ingredients of TRUVADA are emtricitabine and tenofovir DF. See the end of this leaflet for a complete list of ingredients.
- Do not take TRUVADA if you are already taking ATRIPLA®, Combivir
(lamivudine/zidovudine), EMTRIVA, Epivir or Epivir-HBV (lamivudine), Epzicom (abacavir sulfate/lamivudine), Trizivir (abacavir sulfate/lamivudine/zidovudine), or VIREAD because these medicines contain the same or similar active ingredients.
What should I tell my healthcare provider before taking TRUVADA?
Tell your healthcare provider if you:
- are pregnant or planning to become pregnant. We do not know if TRUVADA can harm your unborn child. You and your healthcare provider will need to decide if TRUVADA is right for you. If you use TRUVADA while you are pregnant, talk to your healthcare provider about how you can be on the TRUVADA Antiviral Pregnancy Registry.
- are breast-feeding. You should not breast feed if you are HIV-positive because of the chance of passing the HIV virus to your baby. Also, it is not known if TRUVADA can pass into your breast milk and if it can harm your baby. If you are a woman who has or will have a baby, talk with your healthcare provider about the best way to feed your baby.
- have kidney problems or are undergoing kidney dialysis treatment.
- have bone problems.
- have liver problems including Hepatitis B Virus infection.
Tell your healthcare provider about all the medicines you take, including prescription and non-prescription medicines, vitamins, and herbal supplements. Especially tell your healthcare provider if you take:
- Videx, Videx EC (didanosine). Tenofovir DF (a component of TRUVADA) may increase the amount of Videx in your blood. You may need to be followed more carefully if you are taking TRUVADA and Videx together. Also, the dose of didanosine may need to be reduced.
- Reyataz (atazanavir sulfate) or Kaletra (lopinavir/ritonavir). These medicines may increase the amount of tenofovir DF (a component of TRUVADA) in your blood, which could result in more side effects. You may need to be followed more carefully if you are taking TRUVADA and Reyataz or Kaletra together. TRUVADA may decrease the amount of Reyataz in your blood. If you are taking TRUVADA and Reyataz together, you should also be taking Norvir (ritonavir).
Keep a complete list of all the medicines that you take. Make a new list when medicines are added or stopped. Give copies of this list to all of your healthcare providers and pharmacist every time you visit your healthcare provider or fill a prescription.
How should I take TRUVADA?
- Take TRUVADA exactly as your healthcare provider prescribed it. Follow the directions from your healthcare provider, exactly as written on the label.
- The usual dose of TRUVADA is 1 tablet once a day. TRUVADA is always used with other anti-HIV-1 medicines. If you have kidney problems, you may need to take TRUVADA less often.
- TRUVADA may be taken with or without a meal. Food does not affect how TRUVADA works. Take TRUVADA at the same time each day.
- If you forget to take TRUVADA, take it as soon as you remember that day. Do not take more than 1 dose of TRUVADA in a day. Do not take 2 doses at the same time. Call your healthcare provider or pharmacist if you are not sure what to do. It is important that you do not miss any doses of TRUVADA or your anti-HIV-1 medicines.
- When your TRUVADA supply starts to run low, get more from your healthcare provider or pharmacy. This is very important because the amount of virus in your blood may increase if the medicine is stopped for even a short time. The virus may develop resistance to TRUVADA and become harder to treat.
- Do not change your dose or stop taking TRUVADA without first talking with your healthcare provider. Stay under a healthcare provider's care when taking TRUVADA.
- If you take too much TRUVADA, call your local poison control center or emergency room right away.
What should I avoid while taking TRUVADA?
- Do not breast-feed. See "What should I tell my healthcare provider before taking TRUVADA?"
- Avoid doing things that can spread HIV infection since TRUVADA does
not stop you from passing the HIV infection to others.
- Do not share needles or other injection equipment.
- Do not share personal items that can have blood or body fluids on them, like toothbrushes or razor blades.
- Do not have any kind of sex without protection. Always practice safer sex by using a latex or polyurethane condom or other barrier to reduce the chance of sexual contact with semen, vaginal secretions, or blood.
- ATRIPLA, Combivir (lamivudine/zidovudine), EMTRIVA, Epivir or Epivir-HBV (lamivudine), Epzicom (abacavir sulfate/lamivudine), Trizivir (abacavir sulfate/lamivudine/zidovudine), or VIREAD. TRUVADA should not be used with these medicines.
What are the possible side effects of TRUVADA?
TRUVADA may cause the following serious side effects (see "What is the most important information I should know about TRUVADA?"):
- Lactic acidosis (buildup of an acid in the blood). Lactic acidosis can be a medical emergency and may need to be treated in the hospital. Call your doctor right away if you get signs of lactic acidosis. (See "What is the most important information I should know about TRUVADA?")
- Serious liver problems (hepatotoxicity), with liver enlargement (hepatomegaly) and fat in the liver (steatosis). Call your healthcare provider right away if you get any signs of liver problems. (See "What is the most important information I should know about TRUVADA?")
- "Flare-ups" of Hepatitis B Virus infection, in which the disease suddenly returns in a worse way than before, can occur if you stop taking TRUVADA. Your healthcare provider will monitor your condition for several months after stopping TRUVADA if you have both HIV-1 and HBV infection. TRUVADA is not approved for the treatment of Hepatitis B Virus infection.
- Kidney problems. If you have had kidney problems in the past or take other medicines that can cause kidney problems, your healthcare provider should do regular blood tests to check your kidneys.
- Changes in bone mineral density (thinning bones). It is not known whether long-term use of TRUVADA will cause damage to your bones. If you have had bone problems in the past, your healthcare provider may need to do tests to check your bone mineral density or may prescribe medicines to help your bone mineral density.
Other side effects with TRUVADA when used with other anti-HIV-1 medicines include:
- Changes in body fat have been seen in some patients taking TRUVADA and other anti-HIV-1 medicines. These changes may include increased amount of fat in the upper back and neck ("buffalo hump"), breast, and around the main part of your body (trunk). Loss of fat from the legs, arms and face may also happen. The cause and long term health effect of these conditions are not known at this time.
The most common side effects of EMTRIVA or VIREAD when used with other anti-HIV-1 medicines are: diarrhea, nausea, vomiting, dizziness and headache. Additional side effects are stomach pain, indigestion, gas, inflammation of the pancreas, increased amylase, sleeping problems, abnormal dreams, weakness, pain, low blood phosphate, shortness of breath, increase liver enzymes, inflammation of the liver, allergic reaction, muscle problems and rash. Skin discoloration (small spots or freckles) may also happen with TRUVADA.
These are not all the side effects of TRUVADA. This list of side effects with TRUVADA is not complete at this time because TRUVADA is still being studied. If you have questions about side effects, ask your healthcare provider. Report any new or continuing symptoms to your healthcare provider right away. Your healthcare provider may be able to help you manage these side effects.
How do I store TRUVADA?
- Keep TRUVADA and all other medicines out of reach of children.
- Store TRUVADA at room temperature 77 ° F (25 ° C).
- Keep TRUVADA in its original container and keep the container tightly closed.
- Do not keep medicine that is out of date or that you no longer need. If you throw any medicines away make sure that children will not find them.
General information about TRUVADA:
Medicines are sometimes prescribed for conditions that are not mentioned in patient information leaflets. Do not use TRUVADA for a condition for which it was not prescribed. Do not give TRUVADA to other people, even if they have the same symptoms you have. It may harm them.
This leaflet summarizes the most important information about TRUVADA. If you would like more information, talk with your healthcare provider. You can ask your healthcare provider or pharmacist for information about TRUVADA that is written for health professionals. For more information, you may also call 1-800-GILEAD-5 or access the TRUVADA website at www.TRUVADA.com. Do not use TRUVADA if seal over bottle opening is broken or missing.
What are the ingredients of TRUVADA?
Active Ingredients: emtricitabine and tenofovir disoproxil fumarate
Inactive Ingredients: Croscarmellose sodium, lactose monohydrate, magnesium stearate, microcrystalline cellulose, and pregelatinized starch (gluten free). The tablets are coated with Opadry II Blue Y-30-10701 containing FD&C Blue #2 aluminum lake, hydroxypropyl methylcellulose 2910, lactose monohydrate, titanium dioxide, and triacetin.
Consumer
IMPORTANT NOTE: This is a summary and does not contain all possible information about this product. For complete information about this product or your specific health needs, ask your health care professional. Always seek the advice of your health care professional if you have any questions about this product or your medical condition. This information is not intended as individual medical advice and does not substitute for the knowledge and judgment of your health care professional. This information does not contain any assurances that this product is safe, effective, or appropriate for you.
EMTRICITABINE/TENOFOVIR - ORAL
(em-tri-SITE-ah-bean/te-NOE-fo-veer)
COMMON BRAND NAME(S): Truvada
WARNING: Rarely, this medication can cause severe (sometimes fatal) liver and blood problems (lactic acidosis). Immediately tell your doctor if you develop symptoms of liver problems (e.g., persistent nausea, light-colored stools, stomach/abdominal pain, dark urine, yellowing eyes/skin) or lactic acidosis (e.g., rapid breathing, drowsiness, fast/irregular heartbeat, unusual weakness, feeling cold especially in the arms/legs).
If you have hepatitis B infection along with HIV, your hepatitis symptoms may get worse or become very serious if you stop taking this medication. Talk with your doctor before stopping this medication. Your doctor will perform liver function tests for several months after you stop. Tell your doctor immediately if you develop symptoms of worsening liver problems.
USES: This product is a combination of two different drugs, emtricitabine and tenofovir. This product is used to treat HIV infection. It works by slowing the growth of the virus. Emtricitabine is called a nucleoside reverse transcriptase inhibitor, while tenofovir is called a nucleotide reverse transcriptase inhibitor. They are often referred to as NRTIs.
NRTIs are usually used in combination with other HIV medications (e.g., protease inhibitor). Consult your doctor or pharmacist for more details.
This product and other anti-HIV drugs may help to control your HIV infection, thereby improving your quality of life and lowering your risk of getting complications from HIV (e.g., opportunistic infections, cancer).
This product is not a cure for HIV infection, and it does not prevent the spread of HIV to others through sexual contact or blood contamination (e.g., sharing used needles).
HOW TO USE: Read the Patient Information Leaflet provided by your pharmacist before you start taking this medication and each time you get a refill. If you have any questions, consult your doctor or pharmacist.
Take this medication by mouth, usually once daily with or without food or as directed by your doctor. The dosage is based on your kidney function, medical condition, and response to treatment.
This product is taken with other medicines to treat HIV. If you are also taking didanosine enteric-coated tablets, take both products either on an empty stomach or with a light meal. If you are taking the didanosine buffered tablets, take both drug products on an empty stomach.
Continue taking this medication and your other anti-HIV medications exactly as prescribed by your doctor. This medication works best when the amount of drugs in your body is kept at a constant level. Therefore, take this drug at evenly spaced intervals. To help you remember, take it at the same time each day.
Do not take more or less of this drug than prescribed or stop taking it (or other HIV medicines) even for a short time unless directed to do so by your doctor. Skipping or changing your dose without approval from your doctor may cause the amount of virus to increase, make the infection more difficult to treat (resistant), or worsen side effects. Order your refills early to make sure you do not run out of medication.
SIDE EFFECTS: See also Warning section.
Nausea, vomiting, diarrhea, headache, dizziness, mu


