Completion of Phase I clinical trial of novel Syk Inhibitor HMPL-523 for autoimmune diseases in healthy volunteers

London:  Friday, 30 October 2015:  Hutchison China MediTech Limited ("Chi‑Med") (AIM: HCM) today announces that Hutchison MediPharma Limited ("HMP"), its drug R&D subsidiary, has successfully completed its first-in-human Phase I clinical trial of HMPL‑523.  HMPL‑523 is a novel, highly selective and potent small molecule inhibitor targeting spleen tyrosine kinase, also known as Syk, a key component in B-cell receptor signalling.

The first-in-human Phase I study of HMPL‑523 was a dose-escalating study conducted to assess the safety, tolerability and pharmacokinetics of both single and repeat doses of HMPL‑523 in healthy volunteers in Australia.  The study began in June 2014, and completed ten single dose cohorts, with eight patients per cohort, from 5mg single dose through 800mg single dose.  In April 2015, the multiple ascending dose section of the Phase I study commenced in which HMPL‑523 was administered once daily for 14 consecutive days.  Four dose cohorts have now completed this section of the study, again with eight patients per cohort, from 200mg multiple dose through to 400mg multiple dose.  At 400mg daily, HMPL‑523 drug exposures are believed to be well above the predicted efficacious dose level and, consequently, there is no intention to escalate further in healthy volunteers.

The preliminary safety profile of HMPL‑523 was in-line with our expectations.  No material off-target toxicities such as hypertension and severe diarrhoea were observed with HMPL‑523 in this study.  Furthermore, HMPL‑523 exhibited a linear pharmacokinetic profile and a dose dependent suppression of B-cell activation.  Full results of the Phase I study will be published in due course.

Christian Hogg, CEO of Chi‑Med, said, "We have now established what we believe is a dose range for the further development of HMPL‑523.  This will now allow Chi-Med to move this important, potentially first-in-class compound into global Phase II proof-of-concept studies against multiple indications both in autoimmune diseases and oncology."