Yesterday the U.S. Food and Drug Administration gave its approval to Mavyret (glecaprevir and pibrentasvir) for the treatment of adults with chronic hepatitis C infection. These patients are infected with the Hepatitis C virus (HCV) of genotypes 1-6 and are those that have not developed liver cirrhosis or those who have developed mild cirrhosis. The approval for Mavyret was given to AbbVie Inc.
The patient group that can be treated with this drug may have moderate to severe kidney damage even with dialysis support and that would not preclude the use of Mavyret said the FDA press release statement. The new combo can be used in patients with HCV genotype 1 infection who have already undergone treatment with a regimen either containing an NS5A inhibitor or an NS3/4A protease inhibitor but not both.
Mavyret thus becomes the first approved treatment to be used for eight weeks that can be given to all HCV genotypes 1-6 in patients who have not yet developed cirrhosis and who have not been treated previously. Earlier treatment duration was usually 12 weeks or more.
Edward Cox, director of the Office of Antimicrobial Products in the FDA’s Center for Drug Evaluation and Research said in the press statement that this would be a shorter treatment regimen for patients and also provides a treatment for patients with genotype 1 infection that is the commonest among American HCV infection sufferers who have failed to respond with other therapies. According to the Centers for Disease Control and Prevention nearly 2.7 to 3.9 million American are living with a chronic HCV infection. This infection is a precursor for severe liver damage, cirrhosis, liver failure and even liver cancer and death.
For approval of Mavyret, nearly 2,300 adults with genotype 1-6 HCV infection without cirrhosis or with mild cirrhosis were included in a trial. The effectiveness and safety of this new combo was tested on the patients. Results revealed that 92-100 percent of patients who received Mavyret for eight, 12 or 16 weeks duration showed no virus in their blood 12 weeks after finishing treatment suggesting a cure. 97.5 percent of the participants who did not have cirrhosis were cured. Even among participants who had severe kidney disease, 98 percent were cured after 12 weeks of treatment. The treatment duration differed according to the type of virus, cirrhosis development and history of the infection.
The drug combo has two medicines - glecaprevir and pibrentasvir and is to be taken as three pills once a day. The commonest side effect with the use of Mavyret includes headache, fatigue, itchy skin and nausea. Also in patients who had both Hepatitis B and C infections, treatment with this agent that targets hepatitis C alone leads to activation of the hepatitis B virus that takes upper hand and causes liver damage. Thus all patients who are to be given Mavyret are to be screened for hepatitis B as well. This pill is not recommended for patients who have developed severe cirrhosis and those who are taking other drugs such as atazanavir and rifampin.
AbbVie now had three hepatitis C drugs and there is one from Merck & Co. and four from Gilead Sciences Inc. available for HCV infected persons at present.
Hepatitis C infection
Hepatitis C is a viral infection that can damage the liver over many years. The virus commonly spreads from person to person via an infected person’s blood. Hepatitis C can cause an acute or chronic infection. Acute hepatitis C is a short-term infection with symptoms lasting for up to 6 months. Chronic hepatitis C is a long-lasting infection that can damage the liver over years leading to cirrhosis, liver cancer, liver failure and death. Early diagnosis and treatment of chronic hepatitis C can prevent liver damage.
Persons at high risk of hepatitis C infection are those who use injected drugs, undergo blood transfusions or organ transplants, have hemophilia, or get tattoos with infected needles. In the United States, sharing needles with an infected person is the commonest cause for HCV infection.
There are at least six distinct HCV genotypes, or strains. Treatment can be determined once the genotype is known. In the United States nearly three fourths of individuals have genotype 1. One fourth have genotypes 2 or 3 and few have genotypes 4, 5 or 6.
Treatment options for HCV infection include ribavarin, peginterferon alfa 2a, peginterferon alfa 2b, daclatasvir, elbasvir, ledipasvir, ombitasvir etc.