- What is Viekira Pak, and how does it work (mechanism of action)?
- What brand names are available for Viekira Pak?
- Is Viekira Pak available as a generic drug?
- Do I need a prescription for Viekira Pak?
- What are the side effects of Viekira Pak?
- What is the dosage for Viekira Pak?
- Which drugs or supplements interact with Viekira Pak?
- Is Viekira Pak safe to take if I'm pregnant or breastfeeding?
- What else should I know about Viekira Pak?
What is Viekira Pak, and how does it work (mechanism of action)?
Viekira Pak is a combination of drugs used to treat patients with hepatitis C virus (HCV) genotype 1. It contains four medicines, dasabuvir, ombitasvir, paritaprevir, and ritonavir. Viekira Pak belongs to a class of drugs called direct-acting antiviral agents. Similar drugs include
- boceprevir (Victrelis),
- sofosbuvir (Sovaldi),
- simeprevir (Olysio),
- telaprevir (Incivek), and
- ombitasvir, paritaprevir, ritonavir (Technivie).
Dasabuvir, ombitasvir, and paritaprevir are antivirals that work in three different ways to help stop HCV from multiplying. They block the effect of proteases which are enzymes that HCV uses for making new virus, leading to reduced numbers of HCV copies in the body. Ombitasvir blocks HCV NS5A protease while paritaprevir blocks HCV NS3/4A protease. Dasabuvir blocks a viral structure called NS5B palm polymerase which is also needed for replication of HCV. Ritonavir is not active against the HCV virus. It is used to increase blood levels of paritaprevir by inhibiting the breakdown of paritaprevir.
In clinical studies Viekira Pak, with or without ribavirin (Rebetol) HCV was cured in 95% to 100% of patients treated. Cure was defined as undetectable levels of HCV in the blood 3 months after treatment. The FDA approved Viekira Pak in December 2014.
What are the side effects of Viekira Pak?
The most common side effects of Viekira Pak when used with ribavirin include
- skin reactions such as redness or rash,
- sleep problems (insomnia), and
- feeling weak.
The most common side effects of Viekira Pak when used without ribavirin include
- itching, and
- problems sleeping.
Other side effects include
Quick GuideHepatitis C (Hep C) Symptoms and Treatment
What is the dosage for Viekira Pak?
- Viekira Pak is supplied in monthly cartons that contain enough medicine for 28 days. Each daily dose pack contains four tablets: two 12.5/75/50 mg ombitasvir, paritaprevir, ritonavir tablets and two 250 mg dasabuvir tablets.
- The recommended dose of Viekira Pak is two tablets containing ombitasvir, paritaprevir, ritonavir in the morning and one dasabuvir tablet in the morning and evening. Viekira Pak should be taken with meals.
- Certain patients may also be treated with ribavirin. The dosage of ribavirin is based on weight and is usually administered twice daily with food.
- The recommended treatment regimen and duration of treatment for each type of
HCV infection is as follows:
- Patients with HCV genotype 1a without cirrhosis may be treated with Viekira Pak plus ribavirin for 12 weeks.
- Patients with HCV genotype 1a with cirrhosis may be treated with Viekira Pak plus ribavirin for 24 weeks. (Some patients who have had prior treatment with other drugs may be considered for a shorter treatment duration of 12 weeks.)
- Patients with HCV genotype 1b without cirrhosis may be treated with Viekira Pak for 12 weeks.
- Patients with HCV genotype 1b with cirrhosis may be treated with Viekira Pak plus ribavirin for 12 weeks.
- No dosage adjustment is required in patients with mild liver impairment. Viekira Pak is not recommended for patients with moderate liver impairment and is contraindicated in patients with severe liver impairment.
Which drugs or supplements interact with Viekira Pak?
- Viekira Pak interacts with many drugs. The prescribing information should be consulted for a complete list of drugs that interact with Viekira Pak. Viekira Pak should not be used with the following medications:
- Afluzosin hydrochloride (Uroxatral), a medicine used to treat benign prostate hyperplasia (BPH), due to the risk of hypotension (low blood pressure).
- Certain anti-seizure medications, including carbamazepine (Tegretol), phenytoin (Dilantin), and phenobarbital (Luminal), may decrease the blood concentrations of Viekira Pak and reduce the effectiveness of treatment.
- Rifampin (Rifadin, Rimactane), a component of many tuberculosis treatment regimens, may decrease the blood concentrations of Viekira Pak, reducing the effectiveness of treatment.
- Ergot derivatives which are used to treat migraine headaches should not be used with Viekira Pak due to the risk of ergot toxicity.
- Combination birth control pills that contain ethinyl estradiol should be avoided due to the potential for liver damage.
- St. John's Wort may decrease the blood concentrations of Viekira Pak, resulting in reduced effectiveness of treatment.
- Commonly used cholesterol lowering agents, lovastatin (Mevacor) and simvastatin (Zocor), should be avoided due to the risk for serious muscle pain and injury, including rhabdomyolysis.
- Combining Viekira Pak and pimozide (Orap) may increase the risk for abnormal heart beats.
- Combining efavirenz (Sustiva) and Viekira Pak may increase the risk of liver damage.
- Combining Viekira Pak with sildenafil (Viagra, Revatio) and similar drugs may increase the risk of vision problems, low blood pressure, fainting, and priapism (painful, long lasting erection).
- Viekira Pak increases blood levels of triazolam (Halcion) and midazolam, leading to increased sedation and respiratory depression.
Is Viekira Pak safe to take if I'm pregnant or breastfeeding?
Viekira Pak has not been evaluated in pregnant women. Therefore, Viekira Pak should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.
When Viekira Pak is administered with ribavirin, the combination regimen should not be used in pregnant women and in men who can father children. Ribavirin is known to cause birth defects and should be avoided during pregnancy.
There is an antiretroviral pregnancy registry that monitors the use of products such as Viekira Pak in HCV/HIV-1 co-infected women. Patients are advised to enroll in this program to help study and understand the safety of antiretroviral therapy during pregnancy.
It is not known whether any of the drugs contained in Viekira Pak are excreted into human milk. Due to the lack of conclusive safety data, Viekira Pak should be used cautiously in nursing mothers.
What else should I know about Viekira Pak?
What preparations of Viekira Pak are available?
Tablets: 12.5/75/50 mg ombitasvir, paritaprevir, ritonavir co-packaged with 250 mg dasabuvir tablets.
How should I keep Viekira Pak stored?
Viekira Pak should be stored at room temperature between 15 C and 30 C (59 F and 86 F). Viekira Pak as well as all medicines should be kept out of the reach of children and pets.
Viekira Pak (ombitasvir, paritaprevir, ritonavir, and dasabuvir) is a combination drug prescribed to treat hepatitis C infection to include those patients with compensated liver cirrhosis. Side effects, drug interactions, dosing, storage, and pregnancy and breastfeeding information should be reviewed prior to taking this medication
Multimedia: Slideshows, Images & Quizzes
Hepatitis C (Hep C) Symptoms and Treatment
What is Hepatitis C (Hep C, HVC)? Learn about hepatitis c symptoms, how you get hepatitis c, contagiousness, and hepatitis C...
Hepatitis C Quiz: What is Hepatitis C?
How many Americans have hepatitis C? Take this quiz to learn the facts about this chronic disease....
Liver Disease Quiz: Fatty Liver Disease, Cirrhosis & Symptoms
What is liver disease? Take the Liver Disease Quiz and test your knowledge about this organ and its function....
Picture of Liver
Front View of the Liver. The liver is a large, meaty organ that sits on the right side of the belly. See a picture of the Liver...
Hepatitis in Pictures: What Puts You at Risk?
See how Hepatitis types A, B and C are trasmitted through issues such as poor hygiene, contamination, sexual contact and more....
Related Disease Conditions
Cirrhosis of the liver refers to a disease in which normal liver cells are replaced by scar tissue caused by alcohol and viral...
Liver disease can be cause by a variety of things including infection (hepatitis), diseases such as: gallstones, high...
Liver (Anatomy and Function)
The liver is the largest gland and organ in the body. There are a variety of liver diseases caused by liver inflammation,...
Hepatitis C (HCV, Hep C)
Hepatitis C is an inflammation of the liver due to the hepatitis C virus (HCV), which is usually spread by blood transfusion,...
Hepatitis (Viral Hepatitis, A, B, C, D, E, G)
Hepatitis is most often viral, due to infection with one of the hepatitis viruses (A, B, C, D, E, F (not confirmed), and G) or...
Hepatitis C Cure (Symptoms, Transmission, Treatments, and Cost)
Hepatitis is inflammation of the liver. There are a variety of toxins, diseases, illicit drugs, medications, bacterial and viral...
Is Hepatitis Contagious?
Hepatitis means "inflammation of the liver," and there are several different types of such as A, B, C, D, and E. Some types of...
Is Hepatitis C Contagious?
Hepatitis C or hep C causes acute and chronic liver disease. Hep C is a form of liver disease with symptoms like: fatigue,...
Treatment & Diagnosis
Medications & Supplements
Prevention & Wellness
Daily Health News
Subscribe to MedicineNet's General Health Newsletter
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
Top Viekira Pak Related Articles
CirrhosisCirrhosis of the liver refers to a disease in which normal liver cells are replaced by scar tissue caused by alcohol and viral hepatitis B and C. This disease leads to abnormalities in the liver's ability to handle toxins and blood flow, causing:
- internal bleeding,
- kidney failure,
- mental confusion,
- body fluid accumulation, and
- frequent infections.
Hepatitis CHepatitis C is an inflammation of the liver due to the hepatitis C virus (HCV), which is usually spread by blood transfusion, hemodialysis, and needle sticks, especially with intravenous drug abuse. Symptoms of chronic hepatitis include fatigue, fever, muscle aches, loss of appetite, and fever. Chronic hepatitis C may be cured in most individuals with drugs that target specific genomes of hepatitis C.
Hepatitis C Cure Symptoms and Treatment Costs
Hepatitis is inflammation of the liver. There are a variety of toxins, diseases, illicit drugs, medications, bacterial and viral infections, and heavy alcohol use can case inflammation of the liver. Hepatitis C viral infection (HCV) is one type of hepatitis. According to the CDC, in 2014 there were an estimated 30,500 cases of acute hepatitis C infections in the US. An estimated 2.7-3.9 million people in the US have chronic hepatitis C. The virus is spread from person-to-person via blood-to-blood contact.
Symptoms of HCV infection include joint pain, jaundice, dark urine, nausea, fatigue, fever, loss of appetites, clay colored stool. Hepatitis C can be cured with medications in most people. There is no vaccine against the hepatitis C virus.
Hepatitis C SlideshowWhat is Hepatitis C (Hep C, HVC)? Learn about hepatitis c symptoms, how you get hepatitis c, contagiousness, and hepatitis C treatment for this potentially fatal viral infection that affects the liver.
Hepatitis C QuizHow many Americans have hepatitis C? Take this quiz to learn the facts about this chronic disease.
Hepatitis Risk SlideshowSee how Hepatitis types A, B and C are trasmitted through issues such as poor hygiene, contamination, sexual contact and more.
Is Hepatitis C ContagiousHepatitis C or hep C causes acute and chronic liver disease. Hep C is a form of liver disease with symptoms like:
- nausea and vomiting,
- anorexia, and
- abdominal discomfort.
Is Hepatitis ContagiousHepatitis means "inflammation of the liver," and there are several different types of such as A, B, C, D, and E. Some types of hepatitis are contagious and some types are not. Hepatitis symptoms vary upon the type of disease; however, the following symptoms may develop in someone with hepatitis: fatigue, nausea and vomiting, abdominal pain and discomfort, jaundice (yellowing of the skin and whites of the eyes), and loss of appetite. Treatment for hepatitis depends upon the cause. Some types of hepatitis have a vaccine to prevent spread of disease such as hepatitis A and B.
Liver (Anatomy and Function)The liver is the largest gland and organ in the body. There are a variety of liver diseases caused by liver inflammation, scarring of the liver, infection of the liver, gallstones, cancer, toxins, genetic diseases, and blood flow problems. Symptoms of liver disease generally do not occur until the liver disease is advanced. Some symptoms of liver disease include jaundice, nausea and vomiting, easy bruising, bleeding excessively, fatigue, weakness, weight loss, shortness of breath, leg swelling, impotence, and confusion. Treatment of diseases of the liver depend upon the cause.
Liver Blood TestsAn initial step in detecting liver damage is a simple blood test to determine the presence of certain liver enzymes in the blood. Under normal circumstances, these enzymes reside within the cells of the liver. But when the liver is injured, these enzymes are spilled into the blood stream, and can lead to diseases like fatty liver, type 2 diabetes, obesity, and hepatitis. Several medications also can increase liver enzyme test results.
Liver DiseaseLiver disease can be cause by a variety of things including infection (hepatitis), diseases such as:
- high cholesterol or triglycerides,
- blood flow obstruction to the liver, and
- toxins (medications and chemicals).
- upper right abdominal pain, and
Liver Disease QuizWhat is liver disease? Take the Liver Disease Quiz and test your knowledge about this organ and its function.
Liver PictureFront View of the Liver. The liver is a large, meaty organ that sits on the right side of the belly. See a picture of the Liver and learn more about the health topic.
Liver-Related Procedures and TestsThere are a variety of liver procedures and blood tests. Information on liver biopsy, liver blood tests, liver resection, proton beam therapy of the liver, and more are included in this information.
Viral HepatitisHepatitis is most often viral, due to infection with one of the hepatitis viruses (A, B, C, D, E, F (not confirmed), and G) or another virus (such as those that cause infectious mononucleosis, cytomegalovirus disease). The main nonviral causes of hepatitis are alcohol and drugs. Many patients infected with hepatitis A, B, and C have few or no symptoms of illness. For those who do develop symptoms of viral hepatitis, the most common are flu- like symptoms including: loss of appetite, nausea, vomiting, fever, weakness, tiredness, and aching in the abdomen. Treatment of viral hepatitis is dependant on the type of hepatitis.