This is a Phase Ia, single-center, randomized, double-blind, placebo-controlled, single ascending dose (SAD) study. The primary purpose of this study is to evaluate the safety, tolerability, and pharmacokinetics (PK) of DBM-1152A Inhalation Solution in healthy Chinese adult subjects.

Inclusion Criteria:

1. Chinese healthy male or female subjects.
2. Age 18 to 45 years (inclusive).
3. Body weight: Male ≥50.0kg, Female≥45.0 kg; BMI within the range of 19.0 to 26.0 kg/m^2 (inclusive).
4. Subjects (including their partners) are willing to use effective contraception from the screening period until 6 months after the last dose.
5. Subjects must fully understand the study, participate voluntarily, and sign the written informed consent.

Exclusion Criteria:

1. Clinically significant abnormalities in physical examination, chest X-ray, hematology, urinalysis, blood biochemistry, coagulation function, thyroid function, or ophthalmic examination during screening; or FEV1/FVC < 80% in pulmonary function tests.
2. Positive results in virology screening (HBsAg, anti-HCV, anti-HIV, or TP-Ab).
3. Abnormal vital signs at screening: Sitting systolic blood pressure < 90 mmHg or ≥ 140 mmHg, diastolic blood pressure < 55 mmHg or ≥ 90 mmHg; Pulse < 50 bpm or > 90 bpm; Body temperature < 35.9°C or > 37.6°C; Respiratory rate < 12 breaths/min or > 20 breaths/min.
4. Clinically significant abnormalities in 12-lead ECG, or corrected QT interval (QTc): Male ≥ 450 ms, Female ≥ 470 ms.
5. Electrolyte or glucose abnormalities at screening: Hyperkalemia, hypokalemia, hypermagnesemia, hypomagnesemia, hypercalcemia, hypocalcemia, or hyperglycemia.
6. Current acute or chronic oral or pharyngeal diseases (e.g., oral ulcers, pharyngitis).
7. History or presence of chronic or severe diseases in the endocrine, urinary, digestive, hematological, respiratory, cardiovascular, neuropsychiatric, or immune systems, or any other physiological condition that may interfere with the study results.
8. History or presence of glaucoma, functional constipation, prostatic hyperplasia, urinary tract obstruction, urinary retention, epilepsy, hyperthyroidism, paradoxical bronchospasm, diabetes, or ketoacidosis.
9. History or presence of Short QT Syndrome or Long QT Syndrome.
10. Lower respiratory tract infection within 6 weeks prior to screening, or clinically significant upper respiratory tract disease within 2 weeks prior to screening.
11. Surgery within 3 months prior to screening, especially procedures affecting drug absorption, distribution, metabolism, or excretion; or planned surgery during the study.
12. Suspected allergy to DBM-1152A or its excipients; history of hypersensitivity to other anticholinergic drugs or β2-agonists; or history of significant food or drug allergies.
13. History of drug abuse or drug dependence within 12 months prior to screening.
14. Positive drug screening (morphine, methamphetamine, ketamine, MDMA, or THC) prior to enrollment.
15. Excessive consumption of tea, coffee, or caffeinated beverages (≥8 cups/day, 250mL/cup) within the past 6 months; or consumption of caffeine-rich or grapefruit-rich food/beverages within 48 hours prior to screening.
16. History of alcohol abuse within the past 12 months (Male ≥ 28 units/week, Female ≥ 21 units/week); or regular drinking (≥14 units/week) within 6 months prior to screening; or inability to abstain from alcohol during the study.
17. Positive breath alcohol test (> 0 mg/100 mL) prior to enrollment.
18. Current smoker or history of smoking.
19. Positive nicotine test prior to enrollment.
20. Use of any medications (including prescription, OTC, vitamins, herbal medicine, supplements, or vaccines) within 30 days prior to screening.
21. Participation in any clinical trial of a drug or device within 3 months prior to screening.
22. Blood donation or significant blood loss (> 400 mL) within 3 months prior to screening; or planned blood donation during or within 3 months after the study.
23. Difficulty in venous blood collection or inability to tolerate venipuncture.
24. History of needle syncope or blood syncope.
25. Inability to tolerate inhalation administration.
26. Strenuous exercise within 48 hours prior to screening.
27. Pregnant or lactating women, or women planning pregnancy; use of long-acting estrogen/progestogen injections or implants within 6 months prior to screening; or positive pregnancy test.
28. Male subjects (or their partners) or female subjects planning pregnancy, sperm donation, or egg donation within 6 months after the study, or unwilling to use contraception.
29. Special dietary requirements or inability to comply with the standardized diet.
30. Poor compliance.
31. Any other condition that, in the investigator's opinion, makes the subject unsuitable for enrollment.

Individual participant data (IPD) will not be shared outside the sponsor organization. Data are not being made publicly available due to participant privacy and confidentiality considerations and because there is no established process for external data sharing for this study.

The 1 mg cohort is open-label. The 2 mg, 4 mg, 6 mg, and 9 mg cohorts are double-blind.