A phase 1 healthy volunteer study to assess the excretion and metabolism as well as the absolute bioavailability of oral JMKX003142. The study will be conducted in two parts: Part 1 to assess the mass balance of JMKX003142 using orally administered radiolabelled JMKX003142; part 2 will assess the absolute bioavailability using JMKX003142 and radiolabelled JMKX003142 as intravenous and oral forms

Inclusion Criteria:

1. Chinese healthy males.
2. The age between 18 and 45 years (extremes included), on the date of signing the informed consent form (ICF).
3. Body mass index (BMI) range of 19-26.0 kg/m² (inclusive of boundary values), with body weight not less than 55.0 kg.

Exclusion Criteria:

1. Abnormal findings with clinical significance on comprehensive physical examination, vital signs, digital rectal examination, laboratory tests (complete blood count, blood biochemistry, coagulation function, urinalysis, fecal routine with occult blood, thyroid function), ophthalmological examination, 12-lead electrocardiogram, chest X-ray (posteroanterior view), and abdominal ultrasound (liver, gallbladder, pancreas, spleen, kidneys).
2. White blood cell count and/or hemoglobin below the lower limit of the normal range in complete blood count.
3. Resting corrected QT interval (QTcF) >450 ms (corrected by Fridericia's formula, QTcF = QT/RR^1/3).
4. Hepatitis B surface antigen or E antigen positive, anti-HCV IgG positive, syphilis treponemal antibody positive, and HIV antigen/antibody combination test positive.
5. Subjects with gastrointestinal diseases causing clinically significant symptoms such as nausea, vomiting, diarrhea, or malabsorption syndrome, or those with a history of severe vomiting or diarrhea within one week prior to screening.