Zai Lab (09688) rose more than 5%, with a gain of 5.64% to HK$19.3 at the time of writing. The trading volume reached HK$120 million. On April 18, the company released new preclinical data for ZL-1503, indicating that its internally developed IL-13/IL-31Rα bispecific antibody may provide sustained suppression of severe itching and inflammation caused by atopic diseases. The findings were presented during a poster session at the IMMUNOLOGY2026 conference in Boston, Massachusetts, further supporting ZL-1503's potential as a first-in-class treatment for moderate-to-severe atopic dermatitis and other diseases driven by IL-13 and IL-31. Zai Lab initiated the first-in-human Phase 1/1b clinical study for ZL-1503 in December 2025, with clinical data expected to be announced in the second half of 2026.