The targeted drug Stivarga was approved for the treatment of hepatocellular carcinoma. Stivarga can basically be seen as a step-up from sorafenib, both being multi-targeted kinase inhibitors. It is the first new drug approved by the FDA for liver cancer in the last decade and the first new drug clinically proven to be effective in patients with sorafenib-resistant liver cancer. In the clinical trial, 20% of patients had significant tumor shrinkage and 45% had no tumor growth, adding up to ~65% of patients whose disease was controlled. First of all, the result of “20% significant tumor shrinkage” is not very good, but it is a very good result for liver cancer, a disease with high mortality rate and no good drugs. You may not know that when the standard treatment for liver cancer, sorafenib, was tested in clinical trials, only 2%-7% of patients had tumor shrinkage! From 2-7% to 20% is definitely a qualitative leap. What’s more, many of the patients participating in the clinical trials had already received other therapies and their physical status, including their immune system, was not optimal. If used in patients with better immune system status, or with combination therapy, the results might be even better. Since the vast majority of Chinese liver cancer patients are hepatitis virus carriers, this answer is very important. In this clinical trial, three categories of patients were specifically selected simultaneously: hepatitis B virus carriers, hepatitis C virus carriers, and patients without hepatitis virus. From the final results, there was no significant difference between these three groups. It appears that the effect in hepatitis B carriers was slightly worse than overall (14% vs. 20% shrinkage and 55% vs. 64% control), whether this is true or not needs to be confirmed in subsequent large clinical trials. Not only is efficacy less compromised, but the larger point of this trial is to demonstrate that safety is not compromised either. Since the relationship between the virus and the immune system is also complex, scientists have been concerned that treating cancer by activating the immune system may cause unexpected side effects in hepatitis virus carriers, such as an excessive immune response or a sudden outbreak or even mutation of an otherwise latent virus. Because of this, all previous trials of PD1 immunotherapy have rejected patients carrying the hepatitis virus. To my knowledge, this is the first time that data has been published on immunotherapy for people with the virus. Fortunately, clinical trials have demonstrated that PD1 inhibitors remain safe overall for hepatitis B and C virus carriers, with no unintended toxic side effects.