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

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 medicationwith medium or high dose inhaled glucocorticosteroid (ICS) for at least 12 monthsbefore visit 1.

• 4 Documented treatment with a total daily dose of either medium or high dose ICS forat least 3 months before visit 1.

• 5 At least one additional maintenance asthma controller medication such as Longacting 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 atleast 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 ofFEV1 ≥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 Atvisit 2 or visit 2a.

• 8 Documented history of at least 2 asthma exacerbation events within 12 monthsbefore 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.