A Telura tablets includesof three moieties of anti-retroviral agents like tenofovir DF, lamivudine & efavirenz. Telura tablets are not necessary for curing the infection, but it is expanding in failure of advancement of HIV-1 into AIDS. Telura is needed to reduce the HIV viral replication. Telura is prescription drug used under the guidance of medical practioners
TDF + lamivudine + efavirenz
300mg + 300mg + 600mg
Telura used for
Telura tablets are usedfor adults & pediatric patients of weighing at least 40kg forthe therapy of HIV-1 infection which is applicable
Mechanism of action of Telura
The mainly the drug Telura mechanism which includes in prevention of reverse transcriptase enzyme. The enzyme is needed for HIV viral production.
This prodrug changes into tenofovir by diester hydrolysis and gets phosphorylated to from triphosphate form (nucleoside analogue), infused into viral cells by HIV RT enzyme causes chain termination.
after absorption, go through phosphorylation intracellularly leads to form an active moiety known as lamivudine 5’ triphosphate (nucleoside analogue). This metabolite gets inserted into DNA of HIV virus which is aided by HIV RT & HBV polymerase.
The anti-viral activity of Efavirenz is depends on formation of active triphosphate form of efavirenz by undergoing intracellular conversion. This formed active metabolite entered viral cells by RT causes prevention of newly formed virions by obstruct the DNA duplicates.
ADME Properties of Telura
Tenofovir bioavailability is 25% & increases up to 40% by administering with food. Maximum plasma concentration time of tenofovir is 1.0 plus or minus 0.4 hour The absolute bioavailability of lamivudine is occurring by 86% plus or minus 16%. Lamivudine get absorbed very quickly.
Lamivudine get bounded to human plasma protein by <36% The apparent volume of distribution is 1.3 plus or minus 0.4L/kg. Tenofovir has low protein binding capacity by 0.7% to human plasma protein or <7.2% to serum proteins. The binding nature of efavirenz is nearly 99.5 to 99.75%.
The metabolism of Telura is occurs hepatically. Efavirenz get metabolized by using cytochrome P450 isoenzymes to form metabolites. Lamivudine get metabolized by undergoing biotransformation. Tenofovir metabolism is not induced by cytochrome isoenzymes.
The elimination of tenofovir DF is occurs via glomerular filtration& active tubular secretion. Efavirenz get eliminated via urine and Lamivudine eliminated by urine. The half-lives of Telura ; Tenofovir: 17 hours Efavirenz: 40 to 55 hours Lamivudine: 5 to 7 hours
Dosage & Administration of Telura
Before starting the therapy with Telura , patient should be investigating for presence of HBV infection or not.
The tests like Renal function test&liver function test should be performed.
The usual dose of Telura is one tablet of Tenofovir DF 300mg+Lamivudine 300mg+ Efavirenz 600mg should be administered as once daily.
Telura is a three-drug fixed dose combination: it should be administered on an empty stomach. This tablet should be consumed at bed time due to reducing the neurological problems.
Telura should not be recommended for: Patients who have creatinine clearance less than 50ml/min With severe renal impairment Hemodialysis patient
Telura should not be used for: Moderate & severe liver impairment patients
Side effects of Telura
Lactic acidosis, Aggravation of HBV, Renal damage, Psychiatric problems, Nervous problems, Liver toxicity, Hepatic decompensated cirrhosis, Pancreatitis, Bone defects, Immune reconstitution syndrome, Redistribution of fat, Skin related problems
The most common side effects
Pain in head, lipodystrophy, pain, fever, abdominal pain, back pain, asthenia, diarrhea, nausea, dyspepsia, vomiting, , arthralgia, insomnia
Increased cholesterol, elevation of creatine kinase, increased AST & ALT, Hematuria, neutropenia, increased serum amylase
Warning & precautions
Loss of virological effects:
Thereis a chance of occurring resistance due to Telura is a three-drug fixed dose combination; Monitor the patient’s condition frequently.
Inhibits the problem by measuring the hepatic enzymes level In serious condition discontinue the Telura treatment.
Aggravation of HBV:
After stopping of the anti-HBV agents, reactivation of HBV infection occurs. Prohibit the problem by investigating the patient’s history whether suspected with HBV infection or not.
Embryo fetal damage:
During pregnancy condition the drug Telura is contraindicated
check the liver function test Control the hepatic enzymes In serious condition discontinue the Telura treatment.
Serious hypersensitivity reactions are produced during Telura therapy. Prevent the problem by providing general supportive measures.
During the treatment, loss of calcium levels occurs causes osteomalacia Prevent the problem by providing vitamin D supplements.
Reduce the problem by giving Telura at bed time on an empty stomach.
Immune reconstitution syndrome:
This fatal case is frequently occurred in anti-retroviral therapy. In serious condition stop the Telura tablets.
Discontinue the Telura tablets
Drug- drug interaction
- The drug Telura should not be interact with other anti-retroviral drugs.
- Telura co administration with drugs affecting the kidney functions causes raised concentration of tenofovir and cause to increase the adverse effects.
- Concomitant use with QT prolonged drugs should not occur with Telura
- Telura interaction with anti-fungal, anti-depressants, or anti-infective causes reduced effect of concentration of these drugs
- Concomitant use of Telura with CYP3A inducers causes increased clearance of Telura & leads to reduce the plasma concentration.
- Combination of Telura with anti-malarial, anti-mycobacterial, calcium channel blockers, or lipid lowering drugs causes decreased effect of concentration of these drugs.
- Interaction of Telura with warfarin causes fluctuation in prothrombin time & INR values.
- Combination of Telura with anti-convulsant causes reduced effect of concentration of these drugs.