The study aims to evaluate the pharmacokinetics, mass balance recovery, metabolite profile and metabolite identification of [14C]HRS-1780 following an oral single dose in healthy adult male participants.

Inclusion Criteria:

1. Before the trial, sign the informed consent form, fully understand the trial content, process and possible adverse reactions, and be willing to complete the research as required by the trial protocol.
2. Aged 18 to 45 years old (inclusive) who are in good health and have signed the informed consent form on that day.
3. Body weight of no less than 50 kg and a body mass index (BMI) within the range of 19.0 to 26.0 kg/m2 (inclusive).
4. Participants (including their partners) shall have no intention to have children or donate sperm within three months after signing the informed consent form and shall voluntarily adopt the contraceptive measures stipulated in the protocol.

Exclusion Criteria:

1. Clinically significant abnormalities in vital signs (complete physical examination, laboratory tests, biochemistry, urinalysis, coagulation function, stool routine and occult blood, thyroid function), 12-lead electrocardiogram, digital rectal examination, chest X-rays, abdominal ultrasound.
2. Positive hepatitis B virus (HBsAg), hepatitis B core antibody (HbcAb), hepatitis C virus (HCV Ab), human immunodeficiency virus (HIV), or syphilis at screening.
3. Receipt of medical devices or another investigational drug (including placebo) within the previous 3 months or within the 5 half-lives (whichever is longer), and plan to participate in other clinical trials of drugs or medical devices during the trial period.
4. History of illicit or prescription drug abuse in the past five years or drug addiction within 3 months of screening, or positive urine drug screen at screening/baseline.
5. Use of any prescription medicine within 2 weeks, or over-the-counter (OTC) medicine, herbal remedy, or nutritional supplement, or within 5 half-lives of any drugs, whichever is longer prior to dosing, except for vitamins and occasional use of paracetamol (≤ 2 g/day; no more than 3 consecutive days).
6. History or evidence of clinically significant disorders (including but not limited to immunologic, hepatic, renal, digestive, urinary, psychiatric, respiratory, hematologic, endocrine, or metabolic disorders) and deemed not suitable to participate in the study by the investigator.
7. Severe systemic infections, injuries, or major surgeries as determined by the investigator within 3 months prior to screening, or plan to do surgeries during the study.
8. Whole blood/plasma donation or loss ≥ 200 mL of blood within 3 months prior to dosing; received a blood/plasma transfusion.
9. Alcohol abuse or consumption of more than 14 units of alcohol per week within the previous 6 months (1 unit = 285 mL of beer, or 25 mL of spirits, or 100 mL of wine); or those who have taken alcohol-containing products within 48 hours before administration; or those with a positive alcohol breath test at baseline; or those who were unable to abstain from alcohol during the trial.
10. History of excessive smoking in the past 1 month prior to screening which is defined as more than 5 cigarettes daily (or products with an equivalent amount of nicotine); or positive cotinine test at baseline, or unable to abstain from smoking within 48 h prior to D-1/check-in and during the trial.
11. Receipt of a vaccine within 2 weeks prior to administration or are scheduled to receive a vaccine during the study period and within 1 month after administration.
12. Any other circumstances (e.g., not suitable for venous access) or laboratory abnormality that, in the investigator's judgment, may increase the risk to the participant, or be associated with the participant's participation in and completion of the study or could preclude the evaluation of the participant's response.