POLYETHYLENE GLYCOL CONJUGATE DRUG, AND PREPARATION METHOD THERFOR AND USE THEREOF

Disclosed are a polyethylene glycol conjugate drug, and a preparation method therefor and the use thereof. Specifically, the present invention relates to a polyethylene glycol conjugate drug represented by formula A or a pharmaceutically acceptable salt thereof, a method for preparing the polyethylene glycol conjugate drug or the pharmaceutically acceptable salt thereof, an intermediate for preparing the polyethylene glycol conjugate drug or the pharmaceutically acceptable salt thereof, a pharmaceutical composition comprising the polyethylene glycol conjugate drug or the pharmaceutically acceptable salt thereof, and the use of the polyethylene glycol conjugate drug or the pharmaceutically acceptable salt thereof in the preparation of a drug.