This is a randomized, double-blind, placebo-controlled, parallel-group, prospective, multi-center clinical trial, to evaluate the efficacy of silkworm pupa tablets in improving nutritional status and sarcopenia in patients with malignancies who have completed comprehensive treatment. All participants will be randomly assigned (1:1) to either experimental group (n=240): dietary advice + Wanshili Longbao Silkworm Pupa Tablets (main ingredients: freeze-dried active mulberry cocoon pupa powder, maltitol, milk mineral salt, mannitol, maltodextrin), 2 tablets three times daily before meals for 3 months, or control group (n=240): dietary advice + placebo (identical appearance), 2 tablets three times daily before meals for 3 months. The primary endpoint is sarcopenia prevalence at 3 months (based on AWGS 2019 criteria: muscle strength, muscle mass, and physical function).

Inclusion Criteria:

1. fully understand and sign the Informed Consent Form (ICF); willing to follow and able to complete all trial procedures
2. Any gender, age at ICF signing: ≥ 18 years, ≤ 80 years
3. Confirmed diagnosis of malignancy
4. At screening/ enrollment, meet the definition of sarcopenia according to the 2019 Asian Working Group for Sarcopenia
5. Generally good condition, ECOG performance status ≤ 2
6. Agree to provide peripheral blood, stool, and urine samples for biomarker analysis during the study

Exclusion Criteria:

1. Presence of gastrointestinal obstruction preventing oral intake at screening/enrollment
2. Use of immunosuppressants at screening/enrollment
3. Life expectancy ≤ 3 months
4. Presence of malabsorption syndrome or any condition affecting gastrointestinal absorption, e.g., chronic diarrhea (watery stools; daily stool frequency ≥ 5 times)
5. Patients planning pregnancy, pregnant, or breastfeeding
6. Known allergy to any component of the investigational products
7. Presence of severe primary diseases of the heart, brain, lung, liver, kidney, endocrine, blood, nervous systems or other acute/chronic diseases that could significantly affect treatment and prognosis
8. Presence of other severe physical or mental illnesses or laboratory abnormalities that may increase the risk of participating in the study, or patients deemed unsuitable for the study by the investigator

The experimental group uses silkworm pupa tablets; the control group uses a placebo mimicking the silkworm pupa tablets. Statistical personnel will perform blinding for the investigational products according to the requirements. The manufacturer will prepare and provide corresponding food inspection reports according to the requirements for a double-blind design and package accordingly. If the batch number changes during the trial, the manufacturer must provide a new inspection report for the new batch, to be kept by the investigator. Packaging and numbering will be done according to the treatment codes, involving personnel unrelated to the investigators or statisticians. Corresponding numbers will be affixed prominently to the external packaging based on the generated treatment codes. The packaged investigational products will be distributed to the clinical trial centers together.