Ribavirin
Rivavirin is a drug used to treat certain viral infections, a so-called antiviral drug. In chronic hepatitis C, ribavirin is administered in combination with interferon-α to prevent the hepatitis C-induced form of liver inflammation from worsening and to prevent progressive functional impairment of the liver. The active ingredient ribavirin inhibits the multiplication of viruses and can treat complications such as respiratory syncytial virus infection and hemorrhagic fever.Ribavirin is used specifically for chronic hepatitis C virus infection.
Like any drug, ribavirin can cause side effects. Side effects do not have to occur, however, since every person reacts differently to medication. If ribavirin is given as part of a so-called inhalation treatment, rashes, redness and swelling of the skin often occur.
A slight cramping of the respiratory muscles may occur. Rarely do headaches, shortness of breath, mild anaemia, coughing and changes in breathing occur during inhalation treatment. In individual cases, severe anaemia may occur.
In combination of ribavirin with interferon-α side effects are very common. These include: Dry mouth, anemia, fever, fatigue, muscle and joint pain, flu-like symptoms, weight loss, diarrhea, vomiting, nausea, sleep disturbances, depression, anxiety disorders and lack of concentration as well as rhinitis, inflammation of the respiratory tract, middle ear infection and urinary tract infections. In addition, the combination therapy often causes increased sweating, reddening of the skin, accelerated heartbeat (tachycardia), high blood pressure, thyroid dysfunction, hearing disorders, psoriasis, cycle disorders in women and many other complaints. Despite frequent side effects, the combination therapy of ribavirin and interferon-α leads to a cure for most of those affected. Until 2011, this therapy was the standard treatment and cured about 80% of those affected, so that RNA of the hepatitis C virus could no longer be detected.
New drugs in hepatitis C
The newer drugs used to treat hepatitis C infection can be divided into different classes. There are drugs that end with -buvir. These are polymerase inhibitors.
Polymerases are enzymes for cell reproduction. These drugs, for example sofosbuvir and dasabuvir, attack an enzyme of the hepatitis C virus, HCV polymerase (RNA-dependent RNA polymerase NS5B). Therefore, drugs that end up on -buvir are also called NS5B inhibitors.
Agents such as simeprevir, i.e. hepatitis C drugs ending in -previr, inhibit another enzyme of the hepatitis C virus, namely NS3/4A protease. This enzyme is important for virus replication, so that replication is inhibited when Simeprevir is used. Drugs that end up on -asvir bind the viral protein NSS5A.
This protein is not an enzyme like the other hepatitis C drugs, but a phosphoprotein that plays an important role in the reproduction of the virus. Examples are Daclatasvir and Elbasvir. With the new hepatitis C virus drugs that end on -buvir, fatigue, headaches, nausea, insomnia and anemia can occur as side effects.
The drug Daclatasvir and other -asvir drugs often cause fatigue, headache and nausea. Common side effects of Simeprevir are skin rash, itching and nausea. The drug may also make the skin sensitive to UV and sunlight (photosensitization).
The new drugs for hepatitis C virus infections attack the virus directly. The drugs are suitable for patients who are untreated or have been unsuccessfully pretreated, with or without liver cirrhosis. The drugs are also suitable for patients who are infected with HIV.
In addition to treatment with interferon and ribavirin, the new options are a good option for patients for whom interferon is not an option. The side effects are far less serious than those of interferon therapy. The prospects of success of the new drugs are promising. The therapies last about 12 weeks and have response rates of 95%.