Evaluate the Efficacy and Safety of TQC2731 Injection in Patients With Severe Asthma.

A Multicenter,Randomized,Double-blind, Placebo-controlled Phase II Clinical Trial to Evaluate the Efficacy and Safety of TQC2731 Injection in Patients With Poorly Controlled Severe Asthma

This is a phase II, multicenter, double-blind, randomized, parallel group, placebo-controlled clinical study to evaluate the effect of three doses of TQC2731 on Annualized Asthma Exacerbation Rates(AAER) in adult subjects with poor control of severe asthma. It is estimated that 220 subjects will be included. The subjects will receive TQC2731 (70 mg Q4w, 210 mg Q4w, 420 mg Q4w) or placebo (Q4w) administered by Subcutaneous (SC) in the ratio of 1:1:1:1.

The study comprised a 5 to 6-week screening period, a 52-week treatment period and a 12-week follow-up period. During the treatment period, the study drug will be administered from day 0 until week 48. The study drug was not administered at the 52nd week.

Inclusion Criteria:

• 1 Age. 18-75
• 2 Documented physician-diagnosed asthma for at least 12 months before visit 1.
• 3 Subjects who have received a physician-prescribed asthma controller medication with medium or high dose inhaled glucocorticosteroid (ICS) for at least 12 months before visit 1.
• 4 Documented treatment with a total daily dose of either medium or high dose ICS for at least 3 months before visit 1.
• 5 At least one additional maintenance asthma controller medication such as Long acting β2 receptor agonist (LABA), leukotriene receptor antagonist (LTRA), theophylline, Long-acting muscarinic antagonists (LAMA), sodium cromoglycate, etc. is required according to standard practice of care and must be documented for at least 3 months.
• 6 Morning pre-BD FEV1 <80% predicted normal At visit 2 or visit 2a.
• 7 Evidence of asthma as documented by either: Documented historical reversibility of FEV1 ≥12% and ≥200 mL in the previous 12 months before visit 1 OR Post-BD (albuterol/salbutamol) reversibility of FEV1 ≥12% and ≥200 mL during screening At visit 2 or visit 2a.
• 8 Documented history of at least 2 asthma exacerbation events within 12 months before visit 1.
• 9 ACQ-6 score ≥1.5 at visit 1
• 10 Body weight ≥ 40 kg at visit 1.

Exclusion Criteria:

• 1 Pulmonary disease other than asthma.
• 2 History of cancer.
• 3 Current smokers or subjects with smoking history ≥10 pack-years.
• 4 Hepatitis B, C, human immunodeficiency virus (HIV) or Syphilis.
• 5 History of anaphylaxis following any biologic therapy.
• 6 History of chronic alcohol or drug abuse within 12 months.
• 7 History of a clinically significant infection.
• 8 Pregnant or breastfeeding.