The study is divided into a screening period (28 days before first dose), treatment period (1 year) , and survival follow-up period.~In the dose escalation stage,the study will follow a 3+3 dose-escalation scheme enrolling cohorts of at least 3 subjects sequentially at escalating doses. The dose escalation phase includes a single-dose phase and a multiple-dose phase. Subjects in the single-dose phase were treated with HX301 monolactate, taken orally before breakfast , and in the multiple-dose phase, the frequency of administration was once daily (QD), 3 weeks continuously, suspended for 1 week, and every 4 weeks (28 days) was a dosing cycle. Dose escalation will continue until identification of an MTD or the maximum dose is reached. Dose-limiting toxicities (DLTs) will be assessed from the first dose of study treatment until 28 days .Blood samples will be collected at regular intervals for pharmacokinetics (PK).~The Tumor evaluation (assessed by the Investigator in accordance with Response Evaluation Criteria in Solid Tumors Version 1.1 [RECIST 1.1] to assess efficacy will start from the first dose and occur every 8 weeks in the first 24 weeks and every 12 weeks thereafter..
Open label, single- and multiple-dose administration, dose-exploratory clinical phase I study to evaluate the safety, tolerability and PK profile of HX301 monolactate capsules in patients with advanced malignant solid tumors and to preliminarily evaluate its antitumor efficacy.