This study is a multicenter, open-label, Phase II, single-arm clinical trial, with a planned enrollment of 200 to 300 subjects. Its primary objective is to evaluate the safety and efficacy of TQH2722 injection in the treatment of seasonal allergic rhinitis.

Inclusion Criteria:

• Aged 18-75, with no gender restrictions.
• Diagnosed with seasonal allergic rhinitis.
• Positive allergen test result.
• The subjects have sufficient exposure to pollen during the pollen season.
• The subject's medical history indicates that the subject had poor control of Seasonal Allergic Rhinitis (SAR) symptoms during the previous pollen season or the subject was dissatisfied with the subjective symptom control.
• Screen for subjects who have a morning iTNSS score of ≥4 on the day of screening; at baseline visit, have a morning iTNSS score of ≥4, and have an average rTNSS score of ≥4 over the past 6 days.
• Good compliance during screening/induction period.
• Subjects with comorbid asthma should have stable medication use before the screening period and have their asthma condition assessed as stable by the investigator or specialist.
• The subjects voluntarily joined this study, signed the informed consent form, and exhibited good compliance.
• The subjects and their partners agree to take effective contraceptive measures throughout the entire study period (from the signing of the Informed Consent Form (ICF) to 3 months after the last administration of the trial drug).

Exclusion Criteria:

• Any abnormal laboratory test value during the screening period or randomization.
• Any disease that researchers consider to be unstable and may affect the patient's safety throughout the entire study period, or affect the study results or their interpretation, or hinder the patient's ability to complete the entire study process.
• Patients with active autoimmune diseases.
• Known or suspected immunosuppressants.
• Subjects with active malignant tumors or a history of malignant tumors.
• Screen for individuals with a history of active tuberculosis within the previous 12 months.
• During the screening period, there is active hepatitis, or the presence of human immunodeficiency virus antibody (Anti-HIV) positivity, or syphilis treponema antibody (Anti-TP) positivity.
• Screen for cases diagnosed with helminthic parasitic infections within the previous 6 months, who have not undergone standard treatment or have experienced ineffective standard treatment.
• Subjects who have received specific medications or undergone any nasal or sinus surgery within the specified timeframe.
• Intravenous immunoglobulin (IVIG) therapy and/or plasma exchange within 30 days before screening.
• Screen subjects who have used monoamine oxidase inhibitors within the previous 14 days.
• Initiate allergen immunotherapy within 3 months prior to screening.
• Screen for individuals who have received attenuated live vaccines within the previous 4 weeks or plan to receive attenuated live vaccines during the study period.
• Screen for systemic Chinese herbal preparations used for the treatment of AR with short- or medium-acting systemic glucocorticoids within 4 weeks, or screen for long-acting Systemic Corticosteroids (SCS) received within the previous 6 weeks.
• Suffering from chronic active or acute infection within 2 weeks before screening or during the screening and import period.
• Patients with concomitant asthma should be excluded if they meet any of the following conditions: a. forced expiratory volume in one second (FEV1) ≤ 50% of the predicted normal value; b. acute exacerbation of asthma within 90 days prior to screening; c. currently using fluticasone propionate at a daily dose of >1000 μg/day or equivalent doses of other inhaled corticosteroids; d. assessed by the investigator or specialist as having unstable asthma.
• The subject has a concomitant disease that renders them unable to complete the screening period assessment or evaluate the primary efficacy endpoint.
• Suffering from malignant and benign tumors in the nasal cavity.
• Subjects with perennial allergic rhinitis (PAR) who are allergic to pet hair.
• Unable to use nasal corticosteroid sprays or antihistamines.
• Have a history of systemic allergy to any biological agents.
• Women who are pregnant or breastfeeding.
• Individuals who abuse alcohol, use drugs, and have known drug dependency.
• History of major organ transplantation or hematopoietic stem cell/bone marrow transplantation.
• According to the researcher's judgment, there are any medical or psychiatric symptoms that may put the subjects at risk, interfere with their participation in the study, or interfere with the interpretation of the study results.
• The forced expiratory volume in one second (FEV1) of the subject is less than or equal to 50% of the predicted normal value.
• Other reasons why the researcher believes it is inappropriate to participate in this trial.