Efficacy and Safety of Ixekizumab in Patients with Refractory Guttate Psoriasis

Inclusion Criteria: 1. Patients voluntarily participate in the study and sign an informed consent form; 2. Age between 18 and 70 years, both genders are eligible; 3. Clinically diagnosed with guttate psoriasis; 4. Previously treated with traditional therapies for plaque psoriasis for more than 4 weeks (including antibiotics, topical corticosteroids, topical calcipotriene, phototherapy); 5. Current PASI score ≥ 3 or DLQI score ≥ 6; 6. Investigator assesses participants's suitability for treatment with ixekizumab; 7. No prior use of biologic agents for treatment; 8. Basic understanding of the purpose of the trial, its effects, and potential adverse events, and willing to sign the informed consent form according to the principles of the Helsinki Declaration; 9. Agree to receive regular treatment, follow-up, and undergo relevant examinations according to the clinical research protocol. Exclusion Criteria: 1. Presence of other psoriasis phenotypes such as plaque, pustular, erythrodermic, or psoriatic arthritis; 2. Concomitant severe skin diseases, tumors, other systemic diseases (such as inflammatory bowel disease), or mental disorders; 3. Concurrent infections such as tuberculosis, HIV, hepatitis B, hepatitis C, etc.; 4. Allergy to ixekizumab; 5. Received systemic corticosteroids or immunosuppressive/immunomodulatory drugs for psoriasis treatment within the previous 4 weeks (including but not limited to methotrexate, cyclosporine, acitretin, azathioprine, hydroxychloroquine, apremilast, JAK inhibitors, etc.); 6. Participation in another clinical trial within the past 3 months; 7. Pregnant, lactating women, or those planning to become pregnant during the trial; 8. Other circumstances deemed inappropriate for inclusion by the investigator.