The purpose of this study is to evaluate the efficacy and safety of Lifei Qingchang Granules in the treatment of patients with stable bronchiectasis. This is a multicenter, randomized, double-blind, placebo-controlled clinical trial.

Researchers plan to enroll a total of 150 adult participants (aged 18-75) who have been diagnosed with stable bronchiectasis and experience at least one acute exacerbation in the past 12 months. Participants will be randomly assigned into two groups in a 1:1 ratio:

• The treatment group will receive Lifei Qingchang Granules along with standard postural drainage therapy.
• The control group will receive a matching placebo along with standard postural drainage therapy.

The treatment period will last for 3 months. The main goal is to see if the treatment can improve patients' respiratory symptoms and overall quality of life.

Bronchiectasis is characterized by pathological dilation of the bronchi, with main symptoms including chronic cough and expectoration. Currently, there is no specific cure, making it an urgent clinical problem. In Traditional Chinese Medicine (TCM), the pathogenesis of bronchiectasis is closely related to "phlegm-heat obstructing the lungs".

Lifei Qingchang Granule is an in-hospital preparation patented by the First Affiliated Hospital of Guangzhou Medical University (Patent No.: ZL202110246137.5, Guangdong Medical Preparation No. Z20240007001). Previous clinical observations suggest it effectively reduces acute exacerbations, decreases hemoptysis, and lowers hospitalization rates. This study aims to conduct a pre-clinical study for the transformation of this in-hospital preparation into a new drug.

This prospective, multicenter study plans to enroll 150 participants. Eligible participants must meet the diagnostic criteria for stable bronchiectasis, exhibit the TCM syndrome of "phlegm-heat obstructing the lungs," and have a history of at least one acute exacerbation in the previous 12 months.

Participants will be stratified based on their previous 12-month exacerbation frequency (<3 and ≥3 times) and randomized via an Interactive Web Response System (IWRS) into the herbal treatment group or the placebo group. Both groups will receive standardized postural drainage.

The primary efficacy endpoint is the change from baseline in the respiratory dimension score of the Quality of Life-Bronchiectasis questionnaire at month 3. Secondary endpoints include the St. George's Respiratory Questionnaire (SGRQ) score, 24-hour sputum volume, sputum characteristics (color and consistency), sputum bacteriology, TCM symptom scores, and pulmonary function tests (FVC, FEV1) at month 3. Safety assessments, including vital signs, laboratory tests, and adverse event monitoring, will be conducted throughout the study.

Inclusion Criteria:

• Aged 18 to 75 years old, regardless of sex.
• Diagnosed with bronchiectasis confirmed by High-Resolution Computed Tomography (HRCT) scan.
• Bronchiectasis is currently in the stable phase.
• Experienced at least one acute exacerbation of bronchiectasis within the previous 12 months.
• Diagnosed with the Traditional Chinese Medicine (TCM) syndrome of "Phlegm-Heat Obstructing the Lungs".
• Able to understand the study protocol and voluntarily sign the informed consent form.

Exclusion Criteria:

• Allergic to any ingredients of the investigational drug or placebo.
• Comorbid with other severe systemic diseases (e.g., coronary heart disease, stroke, severe hypertension [systolic BP ≥ 180 mmHg or diastolic BP ≥ 110 mmHg], active gastric ulcer, uncontrolled diabetes [fasting venous blood glucose ≥ 10 mmol/L], malignant tumors, abnormal liver or kidney function [AST, ALT, or GGT > 2 times the upper limit of normal; or serum creatinine > 2 times the upper limit of normal]) or psychiatric disorders.
• Comorbid with asthma, allergic bronchopulmonary aspergillosis (ABPA), or active pulmonary tuberculosis.
• Comorbid with chronic obstructive pulmonary disease (COPD) and presenting COPD as the primary clinical manifestation (as judged by the investigator).
• Use of inhaled, oral, or intravenous antibiotics within 4 weeks prior to enrollment.
• Type 2 respiratory failure requiring long-term non-invasive mechanical ventilation or oxygen therapy (> 10 hours/day).
• History of drug abuse, psychotropic drug dependence, or alcohol abuse.
• Current smokers or those unable to stop smoking during the study.
• Pregnant or lactating women, planning to become pregnant during the study, or refusing to use reliable contraceptive methods throughout the study period.
• Participation in any other clinical trials within 3 months prior to enrollment.
• Considered unsuitable for participation in this clinical study by the investigator.

Individual participant data (IPD) will not be shared publicly to strictly protect patient privacy and comply with the confidentiality agreement approved by the Ethics Committee. All electronic data are encrypted and stored on dedicated hospital servers. Only authorized parties, such as the Ethics Committee and regulatory authorities, have access to the original records under strict confidentiality protocols.

In addition to the roles listed above, data managers and statisticians are also strictly masked to the treatment assignments until the database is locked for final analysis. The experimental drug (Lifei Qingchang Granules) and the placebo are identical in appearance, smell, packaging, and dosage instructions. An independent statistician generates the randomization sequence, which is directly imported into the central Interactive Web Response System (IWRS). Investigators distribute the study drugs solely based on the unique medication code assigned by the IWRS, ensuring the blind is maintained throughout the process.