Phase II/III Seamless Clinical Study of MG-K10 Humanized Monoclonal Antibody Injection in Treatment of Seasonal Allergic Rhinitis

Inclusion Criteria:

• Age of 18-75 years old (including the cutoff value), male or female;

• With reference to the diagnosis and treatment of allergic rhinitis China guide (2022revision) "subjects conforms to the diagnosis of seasonal allergic rhinitis, history 2 years or more clear, at the same time, at least one over the same period of thecurrent season or allergic rhinitis disease related Skin prick test (Skin PrickTest, SPT) or serum Specific IgE (sIgE) (acceptable within less than 1 year beforerandomization), and the results met the diagnostic criteria for SAR

• During the previous pollen season, the subjects used nasal corticosteroids or otherSAR drugs (antihistamines, leukotriene receptor antagonists, etc.), and their SARsymptoms were poorly controlled.

• The following criteria were met at screening and baseline:

1. iTNSS score at screening ≥6, nasal congestion ≥2, runny nose, nasal itching,and sneezing 3. One of the symptoms ≥2 points;

2. iTNSS score ≥6 at baseline; rTNSS≥6 points, nasal congestion ≥2 points, runnynose, nose,one of the three symptoms of itching and sneezing ≥2 points

• Throughout the study period (from signing the ICF to 6 months after the study drugadministration), fertile female subjects and their partners agreed to use highlyeffective birth control, and male subjects and their partners agreed to useeffective birth control and had no plans to donate sperm (men) or eggs (women)

• Be able to understand and comply with clinical protocol requirements, voluntarilyparticipate in clinical trials, and subjects voluntarily sign written informedconsent.

Exclusion Criteria:

• Allergy to the study drug or its excipients;

• Travel plans for 48 hours or more from known pollen areas during thescreening/induction and treatment periods (visit 5);

• The subject's exposure to allergens in his or her home or work environment may havechanged significantly during the trial, which the investigator determines may affectthe efficacy evaluator;

• Subjects with limited outdoor activities during the day were defined as those whodid not have any outdoor activities during the day for 1 or 4 days per week.

·Patients who have previously received anti-interleukin-4 receptor alpha (IL-4Rα)monoclonal antibody drugs (such as dupriuzumab) for Allergic Rhinitis (AR) have poorresponse (such as treatment failure or treatment intolerance);

• Use of antihistamines within 4 days prior to randomization;

• Leukotriene receptor antagonists and hypertrophic cell membrane stabilizers wereused within 1 week before randomization;

• Received medium - and short-acting Systemic Crticosteroids (SCS, including oral,intravenous and intramuscular glucocorticoids) and Chinese medicine for AR treatment (systemic Chinese medicine preparation) within 4 weeks before randomization. Hadreceived long-acting SCS (such as triamcinolone olone injection) within 6 weeksprior to randomization, or planned to receive these medications during the studyperiod;

• Participants with asthma who began inhaled glucocorticoid therapy within the first 4weeks of randomization.

• Stable dose inhaled glucocorticoids were used for at least 4 weeks and evaluatedbefore randomization

• The dose of inhaled glucocorticoids was maintained during the study period, whilethe dosage of inhaled glucocorticoids was ≤1000 μg/ day of fluticasone propionate orequivalent doses of other inhaled glucocorticoids

• Randomized 8 weeks or 5 Systemic immunosuppressants (including but not limited tomethotrexate, cyclosporine, mycophenolate, tacrolimus, penicillamine,sulfasulazopyridine, hydroxychloroquine, azathioprine, cyclophosphamide) have beenused within a half-life (whichever is longer) to treat inflammatory or autoimmunediseases (e.g., rheumatoid arthritis, inflammatory bowel disease, primary biliarycirrhosis, systemic disease) Lupus erythematosus, multiple sclerosis, etc);

• random or 10 weeks before 5 within the half-life of longer (in time) received antiIL - 4 r alpha monoclonal antibody, Thymic Stromal lymphocytes (Thymic StromalLymphopoietin, TSLP) monoclonal antibody, anti-IGE monoclonal antibody, othermonoclonal antibody or other biologic agent therapy;

• Participated in MG-K10 clinical trials;

• Live/attenuated vaccine received within 3 months prior to randomization or duringthe planned study period; Subjects who started Immunotherapy [including IntravenousImmunoglobin (IVIG) therapy or Specific Immunotherapy (SIT) therapy] within 6 monthsbefore randomization, Participants who plan to begin immunotherapy during the study;

• Had received any nasal or sinus surgery within 1 year prior to randomization;

• History of vital organ transplantation (e.g., heart, lung, kidney, liver) orhematopoietic stem cell/bone marrow transplantation

• Other nasal comorbiditis or co-occurring diseases/conditions (such as acute/chronicsinusitis, nasal polyps, deviation of nasal septum, drug-induced rhinitis,cerebrospinal fluid rhinorrhea, nasal postoperative status within 1 year, etc.) werepresent at the time of screening and could affect the efficacy evaluation asassessed by the investigators;

• Acute sinusitis, nasal infection, or upper respiratory tract infection during thescreening/induction period or within 2 weeks prior to screening;

• Have malignant or benign tumors in the nasal cavity;

• Screening for infections requiring treatment with systemic antimicrobials,antivirals, antifungals, antiparasites or antigenics within 7 days prior to thevisit;

• Patients with Perennial Allergic Rhinitis (PAR) who are allergic to pet hair (if thesubject is currently free of pet hair contact) may be included. PAR subjects who areallergic to other indoor allergens may be included);

• Have a history of lymphoproliferative diseases, or have had or are present withmalignant tumors within 5 years prior to screening (except for skin squamous cellcarcinoma in situ, basal cell carcinoma, and cervical carcinoma in situ afterthorough treatment without any signs of recurrence);

• Have a history or evidence of high risk cardiovascular disease

• Have posterior subcapsular cataracts or glaucoma, or any other eye condition thatmay affect the evaluation of eye symptoms, or related conditions listed below

• Active TB infection is present or suspected;

• Presence or suspected worm infection within 6 months;

• A history of severe herpes virus infection, such as herpes encephalitis,disseminated herpes, etc.

• Patients with severe diseases of the central nervous system, respiratory system,liver, kidney, gastrointestinal, urinary, endocrine, or blood systems that theinvestigator believes may affect the efficacy and safety of the subject;

• Known or suspected immunosuppressed individuals, including, but not limited to, ahistory of invasive opportunistic infections (e.g., tuberculosis, histoplasmosis,listeriosis, coccidioidosis, pulmonary cyst disease, aspergillosis), even if theinfection has resolved; Or unusual frequent, recurrent, or long-term infections (asdetermined by the investigator)

• The presence of any significant laboratory anomalies

• Pregnant or lactating women, or those with a positive pre-randomized serum pregnancytest

• According to the judgment of the researcher, it is not suitable to participate inthis researcher for other reasons.