Qiu Renzong said: "the treatment, the doctor has proved to be an effective way to treat patients, the patient is the beneficiary. Or be cured, or the symptom relief. Drug clinical trials, the results are uncertain. The new drug must enter the clinical trial stage after the animal test.

Many new drugs chronic adverse reaction after the listing only gradually revealed, the clinical data of need in clinical use after the listing, or after the listing of clinical trials, so directly relates to the phase IV clinical trials.