A Study of JMT203 in Patients With Cancer Cachexia

Inclusion Criteria:

Inclusion Criteria:

1. Age ≥ 18 years old;

2. Voluntarily participate in the study and sign the informed consent form;

3. Malignant solid tumors confirmed histologically or cytologically, with ongoing orcompleted anti-tumor treatment, and no significant tumor progression within 28 daysprior to the first drug administration:

• Dose escalation and expansion phase (Phase Ia): The investigator predicts thatthere will be no need to change the anti-tumor treatment regimen due to diseaseprogression within the first dosing cycle (21 days) of this study;

• Cohort expansion study phase (Phase Ib): Cohorts A/B/C will enroll patientswith non-small cell lung cancer, pancreatic cancer, and colorectal cancer,respectively;

4. Diagnosed with cancer cachexia according to the criteria of the 2011 InternationalConsensus on Cancer Cachexia: Definition and Classification, combined withcharacteristics of the Chinese population, i.e., presenting with one of thefollowing within 6 months (previous weight data must be supported by writtendocumentation approved by the sponsor): involuntary weight loss >5%, or weight loss >2% when Body Mass Index （BMI） <18.5 kg/m²;

5. Serum Growth Differentiation Factor 15 （GDF-15） levels ≥1300 pg/ml within 28 daysprior to the first study drug administration (applicable to the cohort expansionphase only);

6. Adequate organ function, meeting relevant laboratory test standards: Item Laboratory Test Value Blood Absolute Neutrophil Count ≥1.0×10^9/L PlateletCount ≥75×10^9/L Hemoglobin ≥80 g/L Kidney Serum Creatinine ≤1.5×ULN (if >1.5×ULN,creatinine clearance calculated by the Cockcroft formula must≥30 ml/min) Liver TotalBilirubin ≤1.5×ULN (For patients with liver metastasis, liver cancer, or bile ductobstruction: may be relaxed to ≤3×ULN) AST and ALT ≤3×ULN or ≤5×ULN for patientswith liver metastasis Coagulation APTT ≤1.5×ULN INR ≤1.5×ULN Note: ULN = Upper Limitof Normal; if laboratory tests do not meet the criteria, the investigator willdetermine eligibility based on the patient's overall condition.

8. Eastern Cooperative Oncology Group Performance Status （ECOG PS）score: ≤2;

9. Estimated survival ≥4 months;

10. Fertile eligible patients must use adequate contraceptive measures from the time ofsigning the informed consent form until 6 months after the last drug administration;female patients of childbearing age must have a negative serum pregnancy test within 7 days before the first drug administration.

Exclusion Criteria:

1. Presence of reversible causes leading to decreased food intake;

2. Patients with dysphagia or poor food digestion and absorption, includinggastrointestinal obstruction, active inflammatory bowel disease, or short bowelsyndrome;

3. Patients with cachexia caused by clearly identified other causes, such as severechronic obstructive pulmonary disease, uncontrolled thyroid disease, vital organfailure, or Acquired Immune Deficiency Syndrome （AIDS）;

4. Patients receiving tube feeding or parenteral nutrition therapy during the screeningperiod;

5. Patients who have taken any prescription medications for appetite enhancement orimprove weight loss within 28 days or 5 half-lives (whichever is shorter) before thefirst study drug administration, including but not limited to anamorelin,medroxyprogesterone acetate, dronabinol, medical marijuana, etc.;

6. Initiation of systemic glucocorticoids (prednisone >10 mg/day or equivalent doses ofother similar drugs) or other immunosuppressive therapies within 28 days before thefirst study drug administration, excluding pretreatment for antitumor therapy;

7. Patients with a BMI exceeding 30 kg/m²;

8. Patients who have undergone major surgery within 4 weeks before the first study drugadministration and have not recovered, or are expected to undergo major surgeryduring the study;

9. Patients who have received other clinical study medications within 4 weeks or 5half-lives (whichever is shorter) before the first study drug administration;

10. Patients with severe infections requiring intravenous antibiotics, antivirals, orantifungals during the screening period;

11. Patients with difficult-to-control moderate to large amounts of serous cavityeffusion, such as pericardial effusion or pleural/abdominal/pelvic effusion, within 14 days before the first study drug administration;

12. Patients with a second primary active malignancy within 2 years before the firststudy drug administration, excluding locally curable tumors that have undergoneradical treatment (e.g., resected basal cell or squamous cell skin cancer,superficial bladder cancer, breast carcinoma in situ);

13. Patients with active central nervous system metastases (brain metastases,carcinomatous meningitis, and spinal cord metastases), except for those withcontrolled lesions confirmed by imaging studies within 28 days before the first useof the investigational product;

14. History of severe cardiovascular disease, including but not limited to:

15. Severe cardiac rhythm or conduction abnormalities, such as ventriculararrhythmias requiring clinical intervention, second- or third-degreeatrioventricular block, etc.;

16. Occurrence of acute coronary syndrome, congestive heart failure, stroke, orother cardiovascular events of grade 3 or higher within 6 months before thefirst study drug administration;

17. New York Heart Association functional class ≥III or left ventricular ejectionfraction (LVEF) <50%;

18. Patients with severe immune deficiency or a history of organ transplantation;

19. Patients with recent (within the past year) or current depression or suicidalideation/tendencies;

20. Known allergy to JMT203 or its components;

21. History of severe allergic reactions or uncontrollable allergic asthma;

22. Patients deemed unsuitable for participation in this clinical study by theinvestigator for other reasons.