This is a randomized, Open-label, Phase Ib/IIa study to evaluate the efficacy and safety of SPH4336 monotherapy or in combination with Cadonilimab in the patients with selected advanced solid tumors.

Inclusion Criteria:

1. Subjects voluntarily participate in this study and sign informed consent.
2. Expected survival ≥3 months.
3. Patients with advanced solid tumors (including advanced Well differentiated/dedifferentiated liposarcoma) who cannot be treated by radical surgery/other local treatment.
4. According to RECIST v1.1, participants in the dose expansion phase must have at least one measurable lesion.
5. The laboratory test results meet the organ function requirements before starting the study treatment.
6. Prior to the start of the study treatment, the peripheral nerve toxicity of previous anti-tumor drug treatment had returned to ≤ grade 2, and other reversible toxic reactions had returned to ≤ grade 1, but hair loss/pigmentation and other effects were assessed by the investigator as beneficial to the subjects receiving the study treatment. The toxicity of the risk is not subject to this limitation.
7. Subjects agree to use effective contraception from the time they sign the informed consent to the last time they use the study drug.

Exclusion Criteria:

1. Taking anti-tumor traditional Chinese medicines at the time of signing the ICF.
2. Had undergone surgery prior to treatment and hasn't yet recovered from adverse effects of surgery.
3. Had a history of other malignancies before starting the study.
4. History of myocardial infarction, unstable angina pectoris, severe arrhythmia, and symptomatic congestive heart failure before the start of study treatment; NYHA Class ≥II; QTcF≥ 470 ms; LVEF≤ 50%.
5. Diseases affecting drug administration or gastrointestinal absorption before the start of the study and assessed by the investigators could not be included in the study.
6. Previous history of organ transplantation.
7. Before starting the study, HBsAg positive patients with HBV DNA > 500IU/ mL or 2500 copies /mL or the lower limit of the study center detection, or HCV antibody positive patients with HCV RNA positive, or known HIV-infected patients, or known active tuberculosis.
8. Accompanied by any other serious, progressive, or uncontrolled disease.
9. Subjects with a known history of immune-related adverse events that the investigator determined could not be included.
10. History of severe allergic disease, history of severe drug allergy, or known allergy to any component of the investigational product.
11. Women who are pregnant or breastfeeding.
12. Any other reason for which patients are ineligible for the study as assessed by the investigator.