Health Canada Approves ATRIPLA For HIV Treatment
Bristol-Myers Squibb Company, Gilead Sciences announced that Health Canada has approved ATRIPLA (efavirenz 600 mg/emtricitabine 200 mg/tenofovir disoproxil fumarate 300 mg) for the treatment of HIV-1 infection in adults. With this Notice of Compliance, ATRIPLA becomes the first once-daily single tablet regimen for HIV approved in Canada for use as a stand-alone therapy or in combination with other antiretrovirals.
ATRIPLA combines SUSTIVA (efavirenz), manufactured by Bristol-Myers Squibb Company, and Truvada (emtricitabine/tenofovir disoproxil fumarate), manufactured by Gilead Sciences. Truvada itself is a fixed-dose product that contains two of Gilead's anti-HIV medications, Viread (tenofovir disoproxil fumarate) and Emtriva (emtricitabine), in a single once-daily tablet for use as part of combination therapy. All three medicines work by blocking reverse transcriptase, an enzyme necessary for HIV replication.
"ATRIPLA represents a milestone in treatment for this disease," said Mark Wainberg, MD, director of the McGill AIDS Centre and professor of medicine and microbiology at McGill University. "I commend the companies involved for joining forces to make ATRIPLA, the first complete three-drug regimen in a single once-daily pill."
ATRIPLA was developed through a joint venture partnership between Bristol-Myers Squibb Company and Gilead Sciences. The product was approved by the U.S. Food and Drug Administration in July 2006 and has since become the most-prescribed treatment regimen for patients starting HIV therapy in the United States. In Canada, approximately 60,000 people are living with HIV, and around 2,500 new HIV diagnoses are reported each year.
Clinical data support the use of the three-drug regimen contained in ATRIPLA in HIV treatment-naive patients. A randomized, open label, active-controlled, multicenter, non-inferiority study, Study 934, compared a once-daily regimen of Viread, Emtriva and SUSTIVA, the components of ATRIPLA, with twice-daily Combivir (lamivudine/zidovudine) and once-daily SUSTIVA in treatment-naive patients with HIV. Through 48 weeks, 84 percent of patients in the Viread/Emtriva/SUSTIVA group (n=244) compared to 73 percent of patients in the Combivir/SUSTIVA group (n=243) achieved and maintained a viral load of less than 400 copies/mL. This difference largely results from the higher number of discontinuations in the Combivir/SUSTIVA group due to adverse events (9 percent vs. 4 percent in the Viread/Emtriva/SUSTIVA group) and other reasons including loss to follow-up, patient withdrawal, non-compliance and protocol violation (14 percent vs. 10 percent in the Viread/Emtriva/SUSTIVA group).
In addition, 80 percent and 70 percent of patients in the Viread/Emtriva/SUSTIVA group and the Combivir/SUSTIVA group, respectively, achieved and maintained a viral load less than 50 copies/mL through 48 weeks. Selected treatment-emergent adverse events (Grades 2-4) reported in greater than or equal to 5 percent of patients in the Viread/Emtriva/SUSTIVA group through 48 weeks included dizziness, nausea, diarrhea, fatigue, headache and rash.
Important Product Safety Information About ATRIPLA (efavirenz 600 mg/emtricitabine 200 mg/tenofovir disoproxil fumarate 300 mg), Emtriva (emtricitabine), Viread (tenofovir disoproxil fumarate [DF]) and Truvada (emtricitabine/tenofovir DF)
Lactic acidosis and severe hepatomegaly with steatosis, including fatal cases, have been reported with the use of nucleoside analogues alone or in combination with other antiretrovirals.
Emtriva, Viread, Truvada and ATRIPLA are not approved for the treatment of chronic hepatitis B virus (HBV) infection and their safety and efficacy have not been established in patients co-infected with HBV and HIV. Severe acute exacerbations of hepatitis B have been reported in patients who have discontinued Viread or Emtriva, which are components of Truvada and ATRIPLA. In some of these patients 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 co-infected with HIV and HBV and discontinue Truvada or ATRIPLA. If appropriate, initiation of anti-hepatitis B treatment may be warranted.
It is important for patients to be aware that anti-HIV medicines including Truvada, Viread, Emtriva, SUSTIVA and ATRIPLA do not cure HIV infection or AIDS and do not reduce the risk of transmitting HIV to others.
Additional Important Information About ATRIPLA
ATRIPLA (efavirenz 600 mg/emtricitabine 200 mg/tenofovir disoproxil fumarate [DF] 300 mg) is indicated for use alone as a complete regimen or in combination with other antiretroviral agents for the treatment of HIV-1 infection in adults.
Coadministration of ATRIPLA with astemizole, bepridil, cisapride, midazolam, pimozide, triazolam, ergot derivatives, or voriconazole is contraindicated. Concomitant use of ATRIPLA with St. John's wort (Hypericum perforatum) or St. John's wort-containing products is not recommended.
Since ATRIPLA contains efavirenz, emtricitabine, and tenofovir DF, ATRIPLA should not be coadministered with SUSTIVA (efavirenz), Emtriva (emtricitabine), Viread (tenofovir disoproxil fumarate), or Truvada (emtricitabine/tenofovir DF). Due to similarities between emtricitabine and lamivudine, ATRIPLA should not be coadministered with drugs containing lamivudine, including Combivir (lamivudine/zidovudine), Epivir or Epivir-HBV (lamivudine), Epzicom(TM) (abacavir sulfate/lamivudine), or Trizivir (abacavir sulfate/lamivudine/zidovudine).
Serious psychiatric adverse experiences, including severe depression (2.4%), suicidal ideation (0.7%), nonfatal suicide attempts (0.5%), aggressive behavior (0.4%), paranoid reactions (0.4%), and manic reactions (0.2%), have been reported in patients receiving efavirenz. In addition to efavirenz, factors identified in a clinical study that were associated with an increase in psychiatric symptoms included a history of injection drug use, psychiatric history, and use of psychiatric medication. There have been occasional reports of suicide, delusions, and psychosis-like behavior, but it could not be determined if efavirenz was the cause. Patients with serious psychiatric adverse experiences should be evaluated immediately to determine whether the risks of continued therapy outweigh the benefits.
Fifty-three percent of patients reported central nervous system symptoms (including dizziness [28.1%], insomnia [16.3%], impaired concentration [8.3%], somnolence [7.0%], abnormal dreams [6.2%], and hallucinations [1.2%]) when taking efavirenz compared to 25% of patients receiving control regimens. These symptoms usually begin during Days 1-2 of therapy and generally resolve after the first 2-4 weeks of therapy; they were severe in 2.0% of patients, and 2.1% of patients discontinued therapy. After 4 weeks of therapy, the prevalence of nervous system symptoms of at least moderate severity ranged from 5% to 9% in patients treated with regimens containing efavirenz. Nervous system symptoms are not predictive of the less frequent psychiatric symptoms.
It is recommended that creatinine clearance (CrCl) be calculated in all patients prior to initiating therapy and as clinically appropriate during therapy with ATRIPLA, and routine monitoring of CrCl and serum phosphorous be performed for patients at risk of renal impairment. ATRIPLA should not be given to patients with CrCl <50 mL/min. Renal impairment, including cases of acute renal failure and Fanconi syndrome (renal tubular injury with severe hypophosphatemia), has been reported in association with the use of tenofovir DF. ATRIPLA should be avoided with concurrent or recent use of a nephrotoxic agent.
ATRIPLA may cause fetal harm when administered during the first trimester to a pregnant woman. Women should not become pregnant or breast-feed while taking ATRIPLA. Barrier contraception must always be used in combination with other methods of contraception (e.g., oral or other hormonal contraceptives). If the patient becomes pregnant while taking ATRIPLA, she should be apprised of the potential harm to the fetus.
Mild-to-moderate rash is a common side effect of efavirenz. In controlled clinical trials, 26% of patients treated with efavirenz experienced new-onset skin rash compared with 17% of patients treated incontrol groups. ATRIPLA should be discontinued in patients developing severe rash associated with blistering, desquamation, mucosal involvement, or fever. Skin discoloration, associated with emtricitabine, may also occur.
Liver enzymes should be monitored in patients with known or suspected hepatitis B or C and when ATRIPLA is administered with ritonavir or other medications associated with liver toxicity.
Decreases in bone mineral density (BMD) have been seen with tenofovir DF. Cases of osteomalacia (associated with proximal renal tubulopathy) have been reported in association with the use of tenofovir DF.
Use ATRIPLA with caution in patients with a history of seizures. Convulsions have been observed in patients receiving efavirenz, generally in the presence of known medical history of seizures.
Redistribution/accumulation of body fat has been observed in patients receiving antiretroviral therapy.
Immune reconstitution syndrome has been reported in patients treated with combination antiretroviral therapy, including the components of ATRIPLA.
Saquinavir should not be used as the only protease inhibitor in combination with ATRIPLA.
Coadministration of ATRIPLA and atazanavir is not recommended due to concerns regarding decreased atazanavir concentrations. Atazanavir and lopinavir/ritonavir have been shown to increase tenofovir concentrations. Patients on atazanavir or lopinavir/ritonavir plus ATRIPLA should be monitored for tenofovir-associated adverse events. ATRIPLA should be discontinued in patients who develop tenofovir-associated adverse events.
Coadministration of ATRIPLA with didanosine should be undertaken with caution. Patients receiving this combination should be monitored closely for didanosine-associated adverse events. See Full Prescribing Information for complete list of drug-drug interactions.
In Study 934, the most frequently reported grades 2-4 adverse events through 48 weeks in patients receiving efavirenz + emtricitabine + tenofovir DF were dizziness (8%), nausea (8%), diarrhea (7%), fatigue (7%), headache (5%), rash (5%), sinusitis (4%), depression (4%), insomnia (4%), and abnormal dreams (4%).
The dose of ATRIPLA is one tablet (containing 600 mg of efavirenz, 200 mg of emtricitabine, and 300 mg of tenofovir DF) once daily taken orally on an empty stomach. Dosing at bedtime may improve the tolerability of nervous system symptoms. ATRIPLA is not recommended for use in patients <18 years of age.