Bioequivalence Study of Methacholine for Inhalation (pharmacodynamics)

Bioequivalence Study of Methacholine for Inhalation

This trial was divided into two parts. This is the scecond part. The second part is the pharmacodynamic equivalence study of patients, which is a single-dose, randomized, open, two-cycle, two-sequence crossover design, and plans to enroll 40 subjects.

Inclusion Criteria:

1. adults 18 years old ≤ age ≤65 years old, gender is not limited.
2. Lung function test FEV1≥70% of the predicted value, and FEV1/FVC≥0.7. 3. Patients with clinically diagnosed asthma or others willing to accept bronchial stimulation test.

4. Patients who use contraindicated drugs (β2 adrenergic receptor agonists, anticholinergics, oral bronchodilators, antihistamines, leukotriene receptor antagonists) may be discontinued during the prescribed period prior to airway reactivity examination.

5, voluntary enrollment, signed informed consent, compliance is good, can cooperate with the test observation.

Exclusion Criteria:

1. there is a history of allergy to this reagent.
2. Patients with a history of heart disease who have difficulty tolerating bronchial provocation tests.
3. Patients who had received thoracic or abdominal surgery within 6 months before the trial.
4. Patients who had undergone surgery for intracranial, eye, ear, nose and throat, and respiratory diseases within 6 months before the trial.
5. Patients with respiratory diseases such as pneumothorax or infectious diseases such as tuberculosis.
6. Patients with diseases that may be affected by the use of cholinergic drugs (epilepsy, bradycardia, coronary artery occlusion, vagus nerve tension, thyroid disease, arrhythmia, peptic ulcer, urinary tract disorders, etc.).
7. Patients with a history of drug dependence or alcohol dependence.
8. Severe circulatory system diseases, liver and bile system diseases, digestive tract diseases, urinary system diseases, kidney diseases, blood diseases, endocrine system diseases, immune system diseases, malignant tumors, etc.
9. Patients who are taking cholinase inhibitors (for myasthenia gravis).
10. Patients with unexplained urticaria.
11. Pregnant and lactating women.
12. The subjects had dyspnea, wheezing or wheezing on the test day.
13. have myocardial infarction or stroke, combined with hypertension (systolic blood pressure >200mmHg, diastolic blood pressure >100mmHg) patients.
14. Poor coordination of basic lung function examination and failure to meet quality control.
15. Patients who have used drugs that affect airway contractile function and airway inflammation before the trial and can not be stopped (bronchodilators, glucocorticoids, antiallergens and triene receptor antagonists, etc.).
16. Current smokers, those who had quit smoking for less than one year at the time of screening, and those who had a smoking history of more than 10 pack-years.
17. Patients admitted to hospital for exacerbation of asthma within 12 weeks.
18. combined with patients with respiratory diseases (such as COPD) that may affect the efficacy and safety evaluation of the drug.
19. Researchers believe that there are any cases that are not suitable for inclusion.