Hepatitis C infection, a common liver disease that affects an estimated 4 million people in the United States, is transmitted through exposure to infected blood (blood was not screened for hepatitis C until 1992) and sexual contact with an infected person. The majority of people with the ailment don’t realize that they have the disease because of a lack of symptoms.
Hepatitis C is typically diagnosed when abnormal liver enzymes are identified through a routine blood test or if the infection becomes severe. Seventy percent of patients with hepatitis C develop chronic disease and 30% may develop cirrhosis of the liver within 20 years of exposure to the virus, which causes severe scarring of the liver. An additional 20% of these patients eventually develop liver cancer. About 15,000 deaths are linked to the disease in the United States each year.
Until 2011, there were no proven medicines for patients who didn’t respond to traditional hepatitis C therapy. Two advanced drugs called hepatitis C protease inhibitors, Top 10 selections from Cleveland Clinic in 2011, were the first drugs approved by the Food and Drug Administration (FDA) in a decade. These medications fundamentally changed the treatment for hepatitis C for patients who have not responded to previous therapies.
The drugs belong to a class of medications called protease inhibitors, which work by blocking a key enzyme that viruses need in order to copy themselves and proliferate. When the drug telaprevir (Incivek) is added to standard treatments for hepatitis C, more than 70% of patients can expect sustained viral response (or viral cure) after taking the medication for 24 weeks.
While hepatitis C treatment has improved considerably, especially when compared to the 1990s, the news is even better now. Sofosbuvir, the first all-oral hepatitis C treatment is moving through the final stages of FDA approval. This medication would be the first of a new generation of hepatitis C drugs called direct-acting antivirals (DAA). What the oral DAAs have is the potential to improve what for many has been a very difficult treatment regimen that can take up to 48 weeks and requires injections of interferon, a drug that is difficult to tolerate. More importantly, DAAs can improve treatment response rates to 90% or higher.
In addition to significantly higher cure rates, sofosbuvir—and others in the pipeline—has better tolerability, safety, and a 12-week treatment duration. In the FISSION trial, treatment-naïve patients treated with an oral DAA (1 pill daily) and ribavirin (2-3 pills twice daily) had a 97% cure rate, while those taking standard therapy had a 78% cure rate after 24 weeks of therapy.
In the POSITRON trial, a study with patients who did not respond to standard 24-week therapy or who had relapsed, those who completed 12 weeks of therapy with the oral DAA and ribavirin had an 86% cure rate. An additional 4 weeks of the therapy increased the cure rate to 94%.
An oral drug with the highest cure rates ever and few side effects. It doesn’t get better for people with hepatitis C.
Where Are They Now
New study results have revealed that patients following this treatment regimen had a sustained virologic response rate of up to 99% after four weeks; giving physicians hope that the disease could be completely eradicated in the near future. New drugs of similar mechanism have since been FDA approved and are stated as highly effective in treating all strains of hepatitis C. Two additional novel hepatitis C drugs are in the pipeline and are expected to receive FDA approval by the end of 2017. A vaccine to prevent the transmission of hepatitis C is in its early stages of development, though it is not expected to make a clinical appearance any time soon.