ABLYNX INITIATES PHASE I BIOAVAILABILITY STUDY WITH SUBCUTANEOUS FORMULATION OF ITS ANTI-IL-6R NANOBODY PARTNERED WITH ABBVIE

GHENT, Belgium, 23 April 2014 - Ablynx [Euronext Brussels: ABLX] today announced that it has started dose administration in healthy volunteers in a Phase I clinical trial as part of the evaluation of a subcutaneous formulation of its anti-IL-6R Nanobody^®, ALX-0061, for the treatment of inflammatory diseases, including rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE).

In September 2013, Ablynx and AbbVie entered into a global license agreement, worth up to US$840 million plus double-digit royalties, to develop and commercialise ALX-0061. As part of the agreement, Ablynx is responsible for the Phase I bioavailability study with the subcutaneous formulation (sc) of ALX-0061 and Phase II clinical development of ALX-0061 sc in RA and SLE, both of which are expected to start in 2015. Upon the achievement of pre-defined Phase II success criteria, AbbVie will exercise its right to in-license ALX-0061 and be responsible for subsequent Phase III clinical development and commercialisation.

The Phase I study involves a single-centre, open-label trial to evaluate the bioavailability of ALX-0061 after sc and intravenous (iv) administration in healthy volunteers. In addition, the study will assess the pharmacodynamics, safety, tolerability and immunogenicity of single sc and iv doses of ALX-0061 in healthy subjects. The trial is expected to recruit 70 subjects who will each receive a single dose of ALX-0061, either as a sc injection (50 mg, 150 mg or 300 mg dose) or iv infusion (50 mg or 300 mg dose).

Dr Edwin Moses, CEO of Ablynx, commented:

"We are pleased that our collaboration with AbbVie is progressing well. With the start of the bioavailability study, we are on track for the further development of ALX-0061 as agreed with our partner. Results of the study are anticipated by the end of 2014, with the goal to start Phase II clinical development of ALX-0061 sc in both RA and SLE patients in 2015."

About ALX-0061

ALX-0061 targets the interleukin 6 pathway via its IL-6 receptor (IL-6R), which plays a key role in the inflammation process in RA.  ALX-0061 has been designed to become a best-in-class therapeutic. Its small size (26kD) may potentially allow ALX-0061 to penetrate more effectively into tissues. The potent, monovalent interaction of the molecule with its target reduces the possibility of off-target effects. Its binding to human serum albumin prolongs the in vivo half-life of the product and can lead to improved trafficking to areas of inflammation. The Nanobody has a very strong affinity for soluble IL-6R which should ensure fast target engagement and could result in a fast onset of effect. ALX-0061 appears to benefit from the general Nanobody characteristic of having a very low immunogenic potential.