ABLYNX INITIATES THE PHASE IIb "RESPIRE" STUDY OF ITS WHOLLY-OWNED, FIRST-IN-CLASS, INHALED ANTI-RSV NANOBODY, ALX-0171, FOR THE TREATMENT OF RSV INFECTIONS IN HOSPITALISED INFANTS - Seite 2

Dr Edwin Moses, CEO of Ablynx, commented: "Ablynx is a pioneer in the development of a specific treatment for RSV infections. The start of this efficacy study in hospitalised infants with a RSV infection is another important step forward. If recruitment goes to plan then the study is expected to be completed in the first half of 2018 with results anticipated by the end of 2018."

About the RESPIRE study

The primary objective of the recently reported first-in-infant Phase I/IIa study in 53 hospitalised RSV-infected infants, aged 1-24 months, was to evaluate the safety and tolerability of an inhaled dose (1.5 mg/kg) of ALX-0171, administered once daily for three consecutive days. The results from this study demonstrated that ALX-0171 was safe and well tolerated, had a significant and immediate impact on viral replication and that it had an encouraging initial indication of therapeutic effect.

The benign safety profile of inhaled ALX-0171 observed so far supports the study of increased doses of inhaled ALX-0171 in the Phase IIb RESPIRE efficacy trial, to evaluate the maximum potential of this novel drug candidate and to support selection of the optimal dose for future development and commercialisation.

The RESPIRE study will consist of two parts. The first part will be a sequential dose escalation that will include three cohorts of 12 subjects each of whom will be randomly (3:1 ratio) assigned to receive inhaled ALX-0171 or inhaled placebo. The first cohort will evaluate the safety of inhaled ALX-0171 at a dose of 3.0 mg/kg. After the last subject in this cohort has completed treatment, an independent data monitoring committee (DMC) will review the safety data and advise the Company on proceeding to the next cohort with a dose of 6.0 mg/kg, and the same procedure will then be used prior to the third cohort which will be dosed at 9.0 mg/kg. Recruitment will be paused while the DMC reviews each data set. Following completion of the sequential dose escalation part, the remaining 144 subjects will be randomly assigned in a 1:1:1:1 ratio to one of the three dose groups of inhaled ALX-0171 (3.0 mg/kg, 6.0 mg/kg and 9.0 mg/kg) or inhaled placebo. Subjects will receive once daily doses for three consecutive days and the total study duration per subject will be 28 days.