Since the approval of the combination therapy Daklinza-Sunvepra (Daksun therapy) to receive insurance benefits in April 2015, Korea has used Direct Acting Agent (DAA) therapy for chronic Hepatitis C patients in earnest.

The DAA therapy has since been rapidly replacing the existing standard therapy of Pegeinterferon alfa + ribavirin (IFN+RBV), based on clinical trial results that demonstrated a sharp increase in the full recovery rate of Hepatitis C and the reduction of side effects.

One of the experts who contributed most to introducing the new therapy is Professor Lee Seung-won_이승원 at gastrointestinal internal medicine department of Bucheon ST. Mary’s Hospital_{부천성모병원}. Korea Biomedical Review met Lee to hear his views about the new Hepatitis C therapy and its side effects.

Question: What are notable changes after the introduction of the DDA therapy?

Answer: Upon the news of releasing new drugs, the number of patients who visited our hospital has increased. This seems to be ascribable to the far easier treatment because of fewer side effects. In the past, patients with Gene 1b type Hepatitis C who got treatment of IFN+RBV therapy suffered from side effects and showed 60 percent of sustained virologic response (SVR) for one year. Doctors had to tell patients it didn’t work for 40 percent of them. But SVR rate of DDA therapy has increased and shown fewer side effects. In the case of Daksun therapy, medical bills were more than 1 million won ($891) lower than the ones from the IFN+RBV therapy. Some patients even say they would “get this kind of treatment for more than 100 times.” And DAA therapy can treat various liver diseases regardless of whether they are cirrhosis of the liver or liver cancer or aged patients different from the IFN+RBV therapy, resulting in the expansion of patient groups for treatment.

Q: You mean some patients knew they caught Hepatitis C but didn’t get treatment?

A: Yes. Three types of patients have recently visited our hospital: patients who had failed to treat it before, those who had not received treatment after diagnosis (Naïve), and those who had not known the infection but were diagnosed with the disease in a regular medical check-up.

Q: The results of clinical trials for the DDA therapy show SVR12 accounts for more than 90 percent of the total. Do actual clinical trials produce similar results?

A: According to real life data analysis of eight CMC hospitals to be released by 대한간학회Korean Association for the Study of the Liver on June 23, the SVR12 of the Daksun therapy was 95.6 percent (n=520, as of April 2017). This isn’t the final SVR because they will collect data until June 9, but the Daksun therapy is expected to show near equal figures between clinical trial results and real life data. As the Daksun therapy has fewer side effects, few patients tend to stop treatment. We have to monitor side effects, but patients whose liver conditions and creatinine level are right could cure Hepatitis C more quickly.

Q: The clinical trial results of new Hepatitis C drugs used for DAA showed the general SVR rates of higher than 90 percent, but the figures were a little different in detail. How should we understand the minor difference?

A: Real life data is important. The SVR12 of the Daksun therapy in clinical trials was 95 percent, and the figure was 95-96 percent in real life. Sovaldi also showed similar results between clinical trials and real life data. Even though drugs that have 100 percent rate of successful treatment in clinical trials, we need to check their real life data. If the real life data is 100 percent, the result will be encouraging. The real data for a drug becomes accurate only after doctors prescribe it for at least one year.

Q: Some experts say the simultaneous release of new drugs has complicated doctors’ prescription. What is your advice in choosing drugs?

A: It is encouraging for patients to have broader choices. Personally, when I choose drugs, I have a correct understanding of them and decide after I provide the information to patients. I explain success rate for treatment, side effects, interaction with drugs, and prices. Because there are few side effects in DAA, prices and success rate for treatment are the keys to selecting a therapy in the same interaction. For example, the biggest advantage of Daksun is that it was released in Korea for the first time and has many cases of successful treatments, which proved safety and efficacy and real data equivalent to clinical trials.

Another advantage is the price. The Daksun therapy’s price based on 24-week treatment is 2.5million won or 30 percent of the drug cost, the lowest among DDA therapies released. Drug prices are the most important factor in selecting a treatment.

Q: What is the second best measure for patients who failed to cure their diseases with the DDA therapy?.

A: Because there isn’t the second treatment or drugs to receive insurance coverage for a Gene 1b type in Korea, the success of treatment at an early stage is important. Some second treatment drugs are reportedly conducting clinical trials.

Q: What are remaining challenges in Hepatitis C treatment?

A: The number of Hepatitis C patients soared during the period of mass infection but has since remained unchanged. To eradicate Hepatitis C, we should make the screening, diagnosis, and treatment in reassuring ways. Korea has conducted an antibodies test for HCV after the mass infection and can detect it early as wide as the test expands. If we find and treat hidden patients successfully, patient satisfaction will go up. Further, there are other benefits, such as improving public health and increasing convenience.