This study consists of 2 phases. In the dose escalation phase, up to 6 dose levels of SHR3680 (40 mg/day, 80 mg/day, 160 mg/day, 240 mg/day, 360 mg/day, 480 mg/day) will be investigated with a sequential "3+3" design (3 or 6 participants in each dose level). There will be a single-dose pharmacokinetic (PK) run-in period (7 days). Following the first dose, participants will enter a 1 week treatment-free period to evaluate safety and single-dose PK. If not dose-limiting toxicities (DLTs) are observed during the 1-week period, SHR3680 administration will resume at the same dose level.