Ribavirin is a nucleoside analogue, which stimulates the T cells in the body to fight the virus. The drug increases the rate at which HCV, a type of RNA virus, mutates. This process causes the virus' genetic material to change so much that it cannot survive, according to Dr. Raul Andino, in a study published in May 2001 in the Proceedings of the National Academy of Sciences. Ribavirin alone does not get rid of HCV, although it reduces ALT while that drug is taken. It works in conjunction with interferon, however, allowing more people to sustain their response when the two drugs are combined.
In the US, ribavirin alone can be obtained at a lower price through certain compounding pharmacies, making it possible to combine it with other interferons.
The most common side effects associated with the combination therapy are flu-like symptoms, such as headache, fatigue, muscle pain, fever, and the destruction of red blood cells which may be severe enough to result in anemia.
Psychiatric disorders have also been reported. Depression is a fairly common side effect, and in some cases it may become severe. Rare cases of suicidal thoughts and suicidal attempts have been reported.
The combination therapy is associated with a significant risk of abnormal fetal development, and women of childbearing potential should not begin combination therapy until a report of a negative pregnancy test has been obtained.
"A virological response at the sixth month after discontinuation of a combination of interferon-alpha and ribavirin in patients with chronic hepatitis C is predictive of a 97.8% rate of long-term complete (biochemical and virological) response." (Lancet 2000;356:41).
“Prospective, multi-centre, pharmaceutical company-sponsored, randomized clinical trials in the treatment of chronic hepatitis C have shown that clearance of hepatitis C virus (HCV) is more likely in those treated with interferons than in untreated patients. Sustained treatment-induced virological clearance is highly correlated with biochemical improvement, continued absence of circulating virus, improved histology, improvements in health-related quality of life, and most probably, a reduced risk of premature death from end-stage liver disease or cirrhosis-related hepatocellular carcinoma. The combination of interferon-2b plus ribavirin is even more likely to result in sustained virological clearance than is treatment with interferon-2b alone and has become the treatment of choice in previously untreated patients.” (American Journal of Gastroenterology Editorial June 2000;95:1392-1393)
Recently, it has come to light that there is a direct relation between interferon/ribavirin therapy and osteoporosis Journal of Hepatology 2000; 33 : 812-817. As well, short term memory loss and neurological problems have been linked to combination therapy, and some patients have suffered permanent neurological damage as a result of the combination therapy.