The Lancet reports that early drug trial results show great promise for a new antiviral drug combination developed for patients infected with the hepatitis C virus (HCV). The new therapy consists of the experimental drugs RG7128 — a polymerase inhibitor that interrupts the production of HCV RNA molecules — and danoprevir — a protease inhibitor that blocks an enzyme required for the virus to replicate. (These drugs work in a similar manner to anti-HIV drugs). Meanwhile, the most common antiviral therapy prescribed in the U.S. — injection with pegylated interferon and ribavirin — requires approximately 48 weeks of therapy and has many side-effects. The CDC estimates that between 2.7 and 3.9 million Americans are living with chronic HCV and that 17,000 new cases will be diagnosed this year. Though blood bank screening has virtually eliminated the blood-borne virus’ transmission through blood transfusions, HCV is still transmitted through injection with contaminated needles — such as those used to deliver drugs and draw tattoos — and through sexual transmission.
Researchers recruited 88 HCV patients who had never received treatment or did not respond well to standard treatments. The patients were randomly assigned to seven treatment groups receiving different combination therapy doses or a placebo for up to 13 days. After 14 days, the patients in the highest dose treatment groups — both previously treated and untreated — experienced a substantial reduction in viral load as compared to those getting the placebo. The researchers predict that the new combination therapy — which exhibited no severe side-effects or signs of drug resistance common in single-drug therapies — could clear HCV infection in 8-12 weeks.
“Clearly, hepatitis C is a very serious problem,” says ACSH's Dr. Gilbert Ross. “Considering the scope of the problem, the inadequacy of previous treatment, and apparent excellence of this treatment, I think we have reason to be excited about this therapy.”
This writer, who worked as a technician in a HCV immunology laboratory before coming to ACSH, adds that many patients don’t experience symptoms for several months or more. “They often won’t know they’re infected unless they go to a clinic for testing or get diagnosed while incarcerated or hospitalized. A majority of these patients are addicted to drugs, so even if they receive testing, they are not as likely to return for follow-up appointments or be able to pay for the expensive drug therapy. Therefore, if a new treatment such as this one can clear the virus in a matter of weeks and require fewer doctor visits, I believe that it would be a great benefit to public health.”