Tenvir L tablets are containing anti-viral agents known as tenofovir disoproxil fumarate and lamivudine. Tenvir L is pharmacologically categorized as adenine analogue reverse transcriptase inhibitor containing anti-viral activity against
HIV-1. Tenvir L is used by combining with other anti-viral agents for better activity. Tenvir L is present as prodrug form, which get converted into an active moiety in-vivo. Tenvir L is also classified as nucleoside reverse transcriptase prohibitor of adenosine.
Tenofovir disoproxil fumarate + lamivudine
300mg + 300mg
Indication of Tenvir L
The primary indications of Tenvir L are; HIV-1 infection
For HIV-1 infection
Tenvir L is used by combining with other anti-retroviral agents during this condition. Tenvir L is applicable for adults & pediatrics with age of 2 years & older. Before beginning the treatment with Tenvir L , caution should be taken; Avoid combination of Tenvir L with Atripla.
Mechanism of Tenvir L
Tenvir L containing an active component like Tenofovir disoproxil fumarate is a prodrug which gets altered into Tenofovir by undergoing intracellular mechanism. Tenofovir is show a hostile to viral action by forbidding the turnaround transcriptase compound by battling with regular substrate deoxyadenosine 5' triphosphate and after addition into DNA, by viral DNA chain eliminator. Tenvir L is used to halt the viral DNA synthesis which is a process of chain elimination.
Lamivudine undergoes phosphorylation intracellularly, to form active moiety known as 5’ triphosphate metabolite, lamivudine triphosphate which exhibits anti-retro viral action. The most important action of this metabolite is prohibition of reverse transcriptasethrough DNA chain elimination which is occurring after insertion of nucleoside analogues
After absorption of Tenvir L tablets, the mean oral bioavailability is reaches by almost 25% is Tenofovir DF and Lamivudine: 86 ± 16%; The high serum concentration time occurs in 1 hour plus or minus 0.4 hours is Tenofovir DF. Tenvir L administered with food.
Tenofovir DF get bounds to human plasma protein or serum proteins by less than 0.7 & 7.2% respectively and <36% for lamivudine.
No cytochrome isoenzymes are involved in the metabolism of Tenofovir DF. The known metabolite of lamivudine is trans-sulfoxide metabolite. Biotransformation is occurred by using sulfotransferases.
The elimination of Tenofovir DF occurs via glomerular filtration & active tubular secretion. After oral administration of single dose of Tenofovir DF, reaches half-life period at almost 17 hours. Nearly 70 to 80% of dose gets eliminated via urine & feces. The major route of elimination of lamivudine occurs via urine as an unchanged form. It also excreted in human milk. The terminal half-life period of lamivudine is 5 to 7 hours.
In HIV-1 infection; (adults & pediatric patients 2 years to less than 12 years of age
Before beginning the therapy with Tenvir L , patient should be examined for presence of HBV infection or not. Follow Renal function & liver function test before the treatment. The Tenvir L recommended dose for adult suffering from HIV infection The administrated one tablet orally given once a day with combination of other antiretroviral agents. Tenvir L 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.
Tenvir L should not be prescribed for
Patients who have creatinine clearance less than 50ml/min With severe renal impairment Hemodialysis patient Tenvir L should not be used for; Moderate & severe liver impairment patients In pediatric patient’s dose: The patients should be weighing at least 35kg administrated one tablet given once a day via orally with combination of other antiretroviral agents.
The most common adverse effects are
Serious acute aggravation of hepatitis New commencement of worsening renal damage, Lactic acidosis, Hepatic steatosis, Bone defects, Immune reconstitution syndrome
The most common side effects
Headache, Pain, Fever, Abdominal pain, Back pain, Asthenia, Diarrhea, Nausea, Dyspepsia, Vomiting, Muscular skeletal disorders, Arthralgia, Myalgia, Depression, Dizziness, Insomnia, Peripheral neuropathy, Anxiety, Respiratory , Pneumonia, Skin rashes, Anemia
Aggravation of hepatitis infection
After conclusion of treatment, patients may suspect with worsening of HBV infection condition. Patient infected with HBV condition should be monitored frequently after discontinuing the HBV anti-viral therapy. In this condition, patient should be resuming the anti-HBV treatment.
New outbreak or worsening of renal damage
Avoid combination of Tenvir L with drugs affecting the renal function. Monitor the renal function by measuring the creatinine clearance, serum protein, serum glucose levels.
Lactic acidosis & hepatic steatosis
This condition should be takes place due to imbalance level of hepatic enzymes. To overcome the problem by monitoring the hepatic function test In severe condition, therapy should be discontinued.
Some drugs may interact with activity of Tenvir L and produced adverse effects. In some condition, over dosage or duplication of therapy should be occurred. Avoid the combination of Tenvir L with Trustiva, Viraday or Atripla.
HIV-1 & HBV co infection
Before initiating Tenvir L treatment in co infected patients, HIV-1 antibody testing should be undergone. Examine the HIV-1 infected patients thoroughly whether they are co infected with HBV infection or not.
During Tenvir L receiving condition, patients bone mineral density will be drops and causes bone related defects like osteomalacia. To overcome the problem by maintain the calcium levels in the body by supplying vitamin D supplements.
Immune reconstitution syndrome
During anti-retroviral treatment, patients must acquire this fatal case. In this condition, discontinue the treatment.