A Trial Evaluating the Efficacy and Safety of SHR-1139 Injection in Adult Patients With Palmoplantar Pustulosis

Inclusion Criteria:

1. Participant is at least 18 years of age at the time of signing the ICF.
2. BMI ≥18 kg/m² at screening.
3. Confirmed diagnosis of PPP for at least 24 weeks prior to the screening visit.
4. PPPASI ≥12 at both the screening visit and baseline visit.
5. PPP-IGA ≥3 at both the screening visit and baseline visit.
6. Participant has at least one palm and/or sole with moderate or severe pustules/vesicles at screening and baseline.
7. Participant is a candidate for systemic therapy or phototherapy.

Exclusion Criteria:

1. Participant has significant improvement in PPP symptoms from the screening visit to baseline visit, defined as a decrease in the PPPASI score.
2. Participant has other skin diseases that would interfere with efficacy assessment.
3. Drug-induced PPP.
4. Participant is receiving or has previously received prohibited or restricted medications, with an interval prior to the baseline visit shorter than the required drug wash-out or stabilization period.
5. Participant has a prior history of lymphoproliferative disorders.
6. Concurrent other active autoimmune diseases.
7. Periodontitis requiring treatment at screening or baseline.
8. Received infection-related tonsillectomy or dental treatment within 24 weeks prior to baseline.
9. Chronic or recurrent tonsillitis or sinusitis at screening or baseline.
10. Participants with any active malignancy or history of malignancy within 5 years prior to screening.
11. Active tuberculosis (TB) or latent tuberculosis infection.
12. Severe, progressive, or uncontrolled cardiovascular, cerebrovascular, hepatic, renal, pulmonary, gastrointestinal, hematopoietic, endocrine, neurological, psychiatric (e.g., depression, suicidal tendencies, and psychological disorders), skin or mucosal diseases, or any other condition that the investigator considers inappropriate for participation in this study.
13. Women who are pregnant or breastfeeding.
14. Allergy to any component of the investigational drug.
15. History of alcohol abuse or illicit drug use within one year prior to screening.
16. Receipt of live attenuated vaccine or live vaccine within 12 weeks prior to randomization, or planned receipt of such vaccines during the study period, or participation in a vaccine clinical trial within 12 weeks prior to randomization.
17. Blood donation of approximately 500 mL within 8 weeks prior to randomization, or planned blood donation during the study period.
18. Undergone major surgery within 8 weeks prior to screening, or planned surgery during the study period.
19. Any other condition judged by the investigator that may affect the safety and efficacy evaluation of the investigational drug.