l HSK47388 was generally well tolerated with no serious adverse events observed to date

l Robust Pharmacokinetic (PK) data demonstrated linear PK and superior Thalf to support QD dosing

l Pharmacodynamic (PD) data demonstrated potent inhibition on ex vivo IFNg secretion across all dose levels tested in the MAD study

l Enhancer formulation exhibited significant increase in exposure, with 50mg comparable to 200mg without enhancer

l Food effect study demonstrated limited impact when dosing 30min prior to meal

l Phase 1 SAD/MAD package supports initiation of Phase 2 trials in Psoriasis and Ulcerative Colitis (UC)

l IND approval was granted by the FDA in Jun2025

Haisco announced positive topline results from the SAD (HSK47388-101), MAD(HSK47388-102), and the enhancer formulation PK (HSK47388-I-101) studies, assessing the safety, tolerability, PK and PD of escalating doses of HSK47388, an oral IL23 inhibitor peptide targeting as an oral treatment for the indications of psoriasis and UC.

The FIH SAD study(HSK47388-101) was conducted in healthy volunteers in Australia, demonstrating a well-tolerated safety profile from 50mg to 800mg. Linear PK was confirmed across the dose levels, with an evidently longer Thalf (16-18hr) compared to the JNJ compound. 

The MAD study(HSK47388-102) in China recruited healthy volunteers which were administered with an oral dose of 100mg to 400mg for 7 days. In addition to the well-tolerated safety profile, potent inhibition on ex vivo IFNg release was observed across all dose levels, with a near complete inhibition and plateauing effect for 200mg and dose above.

The enhancer formulation PK study (HSK47388-I-101) in China showed that the plasma exposure of 50mg enhancer formulation is comparable to that of the 200mg IR tablet without the enhancer. Dosing 30min prior to meal leads to only a mild reduction in exposure compared to the fasting group.

Based on these favorable findings, the Company has initiated the Phase 2 trial in psoriasis in Q4 2025, and anticipates the initiation of Phase 2 trial in UC in Q1 2026.