Virataz R (Atazanavir & Ritonavir)

INDICATION

Virataz R tablets are two medicines fixed dose combination with protease inhibitor activity. Virataz R tablets are primarily indicated for the condition like HIV-1 infection. Virataz R tablets are majorly indicated for adolescents.

MECHANISM OF ACTION

A Virataz R tablet contains Atazanavir & ritonavir as an active substance.

Atazanavir

Atazanavir is pharmacologically classified as an azapeptide protease inhibitor, this may specifically prohibits the virus specific processing of viral Gag & Gag Pol polyproteins present in HIV-1 infected cells. This may results as stoppage of production of new mature virions.

Ritonavir

Ritonavir is pharmacologically categorized as peptidomimetic prohibitor of HIV-1 protease enzyme. This inhibition process restore the enzyme inadequate for the processing the gag-pol polyprotein precursor which undergoes formation of non infectious immature HIV particles.

ADME PROPERTIES

ABSORPTION

Atazanavir is quickly absorbed with the Tmax of relatively 2.5 hours. If Virataz R is taken with food, leads to increase bioavailability of Atazanavir and depletes its pharmacokinetic variability. Oral bioavailability is around 60-68%

DISTRIBUTION

Atazanavir is highly bound to human serum protein nearly 86%. It binds to alpha-1-acid glycoprotein and albumin (89% and 86%) respectively

METABOLISM

The major biotransformation pathways like; Monooxygenation Dioxygenation Virataz R is highly metabolized in liver It is metabolized by CYP3A

ELIMINATION

The route of elimination is not known clearly The terminal half life of Virataz R in healthy persons is around 7 hours Hepatic impairment patients 12.1 hours

DOSAGE MANAGEMENT

DOSAGE AND ADMINISTRATION

Virataz R tablets should be administered with food. Depending up on the therapy history of patients or use of other anti-retroviral drugs, the dosage of Virataz R tablets should be recommended. In case of co administration of Virataz R with H2 receptors antagonist or proton pump inhibitors, dose separation should be needed for reducing the impacts. Patients who are treated with earlier virologic failure, Atazanavir without Ritonavir should not be suggested.

BEFORE BEGIN THE TREATMENT OR DURING THE THERAPY WITH ATAZANAVIR

Renal function test should be performed before the therapy starts. Serum creatinine, creatinine clearance, urinalysis should be tested frequently. Hepatic function test also performed before begin the therapy with Virataz R .

RECOMMENDED ADULT DOSAGE
FOR NEWLY TREATED PATIENTS

The prescribed dose is one Virataz R tablet should be administered orally as once daily with food.

COMBINATIONAL TREATMENT

Virataz R combined with; Tenofovir H2 receptor antagonist: The dose of H2 receptor antagonist should not be maximized while compared to famotidine 40mg as two times a day. The administration of Virataz R & H2 receptor antagonist has time interval of at least 10 hours after the dose of gastric regulators. Proton pump inhibitors: The dose of proton pump inhibitors should not be maximized while compared to pantoprazole 20mg as two times a day. The administration of Virataz R & proton pump inhibitors has time interval of at least 12 hours after the dose of gastric regulators.

FOR ALREADY TREATED PATIENTS

The prescribed dose is one Virataz R tablet should be administered orally as once daily with food.

COMBINATIONAL TREATMENT

Do not take Virataz R tablets, if tenofovir & H2 receptor antagonist have taken together. Do not administer Virataz R tablets with efavirenz due to depletion of atazanavir exposure.

RENAL & HEPATIC IMPAIRMENT PATIENTS

Renal impeded patients, including serious condition are not made do with hemodialysis; dose change ought not to be required for atazanavir. Therapy newly commenced patients with chronic stage renal disease managed with hemodialysis should getting Virataz R tablets. Atazanavir should not recommended for HIV treated experienced patients with chronic stage renal disease with hemodialysis. The safety of Virataz R tablets should be established in mild or moderate hepatic impaired patients. Severe liver impaired patients, Virataz R should not be recommended.

SIDE EFFECTS
SIDE EFFECTS
Abnormalities of cardiac conduction Rash Hyperbillirubemia Advanced renal disease Nephrolithiasis & cholelithiasis

COMMON SIDE EFFECTS
Nausea, Jaundice or scleral icterus, Diarrhea, Fever, depression, Myalgia

LAB ABNORMALITIES
Increased AST, ALT Increased bilirubin Increased lipase Increased creatine kinase Increased cholesterol Neutropenia Increased glucose level

POST MARKETING EFFECTS
Edema, pancreatitis, hepatic function abnormalities, cholelithiasis, arthralgia, alopecia, angioedema

PRECAUTION

Cardiac conduction abnormalities

Virataz r receiving patients may suffer with qt prolongation. Prevent the problem by monitoring the ecg levels periodically.

Serious skin reactions

Severe rash are occurs during the therapy with virataz r tablets. In serious condition stop the therapy.

Hyperbilirubinaemia

Patients who are receiving atazanavir should be suggested with increased bilirubin levels. Dose reduction should not be applicable in long term efficacy. Prevent this worsening condition by monitoring the hepatic enzymes levels during the therapy. In severe condition, the therapy should be discontinued.

Advanced renal failure

In chronic condition, stop the therapy with virataz r tablets. Nephrolithiasis & cholelithiasis; virataz r tablets should be postponed or discontinued.

Diabetes mellitus

During the treatment, patient’s blood glucose level should be elevated. Prevent the problem by measuring the blood glucose level frequently during the therapy. Initiate the anti-diabetic medications.

Fat redistribution

Re accumulation of fat in the body occurs during the treatment, this may leads to cause obesity.

Hemophilia

Increased bleeding occurs during protease inhibitor therapy. Caution should be taken.

STORAGE

Virataz R tablet container should be stored at temperature between 20° to 25°C. Do not refrigerator. Keep away from moisture, heat & light