How long to take nucleoside (acid) antiviral drugs can predict long-term efficacy? Many patients with chronic hepatitis B are taking nucleoside (acid) antiviral drugs for treatment. Can HBV DNA levels drop after antiviral treatment is started? When will it go down? How much? These can predict the long-term efficacy of the drug and whether drug-resistant variants of HBV have occurred. It is important to remember that the faster and greater the decrease in HBV DNA levels after taking a particular antiviral drug, the better the long-term outcome and the less likely it is that the virus will mutate. When is the long-term efficacy of a drug predicted? Experts believe that taking lamivudine up to 16 weeks, tebivudine up to 24 weeks, and adefovir up to 48 weeks is a reasonable point to predict efficacy. If HBV DNA levels monitored at this time point are negative or undetectable, good efficacy is predicted for taking the drug for two years or more. If the rate of viral mutation is low during this period, there is no need to change the original treatment regimen and the patient can continue taking the original drug. Entecavir and tenofovir have low rates of viral mutation because of their strong antiviral capacity (high barrier to genetic resistance, only 1.2% viral mutation in five years of entecavir, and no viral mutation observed so far in eight years of tenofovir), and only need to be monitored according to general monitoring patterns, without the need to list a reasonable prediction of the point of efficacy. Why should the “reasonable efficacy prediction point” be set at 16 weeks for lamivudine, 24 weeks for telbivudine, and 48 weeks for adefovir? 1, lamivudine caused by the higher rate of viral mutation, its antiviral activity and strong, but if the early good results, the rate of viral mutation is not high, so its “reasonable efficacy prediction point” is set at 16 weeks, which is also acceptable for the initial treatment of the drug; 2, adefovir hang virus activity is slower to play, but it caused the Adefovir has a slower viral activity, but it leads to a lower viral mutation rate, so it is appropriate to take it for 48 weeks; 3. The viral mutation rate caused by tebivudine is lower than that of lamivudine and higher than that of adefovir, so taking it for 24 weeks is a “reasonable efficacy prediction point”. Most of the chronic hepatitis B patients in China in the initial treatment of the lower price of lamivudine, adefovir and tibivudine, but some of them caused by the higher rate of viral mutation (such as lamivudine and tibivudine), some of the antiviral effect appeared later, or even the occurrence of primary non-response (such as adefovir). The majority of chronic hepatitis B patients are taking the drugs outside the hospital and find it convenient and safe, believing that there will be no problem as long as they keep taking them. In fact, nucleoside (acid) class of drugs with different antiviral activity, onset of action time is also different, after taking the viral mutation rate is more different, do not regularly monitor the HBVDNA, we do not know whether the HBV in the body is “honest” or “lose”, and do not know whether they have “changed tactics”. We don’t know if HBV is “honest” or “giving in” in the body, or if it has “changed its strategy” (genetic mutation). Therefore, in addition to regular monitoring (generally every 1-3 months), patients must remember the “reasonable efficacy prediction point”, and must go to the hospital to test HBV DNA and ask the doctor to help analyze the situation. If the HBV DNA level monitored at the “reasonable efficacy prediction point” does not fall satisfactorily, or even does not fall, it can be predicted that the long-term efficacy of the drug is not good, or the virus may be mutated. At this point, the doctor has to change the original treatment plan in advance, replace or add another antiviral treatment, to optimize the use of medication, in order to achieve the desired efficacy and pre-hospital viral mutation, which is the turning point of the patient’s treatment, or the “inflection point”. The patient’s “tipping point” is achieved at the “reasonable predictor of efficacy”, and it is important to test for HBVDNA at the “reasonable predictor of efficacy”. Specialists would prefer that patients do not have this “point of inflection”, and that they do not have to change or increase their medications, but simply stay on one medication until they are “cured”. Most patients do not do well and often need to change their treatment strategy. Hepatitis B treatment is a difficult long-term project, without the patient’s tacit cooperation, only the doctor to make efforts, it is difficult to complete.