ABLYNX REPORTS ADDITIONAL CLINICALLY IMPORTANT BENEFITS OF CAPLACIZUMAB FROM ITS PHASE III HERCULES STUDY IN ACQUIRED TTP

Ablynx NV [Euronext Brussels and Nasdaq: ABLX] today announced additional results from the Phase III HERCULES study with caplacizumab, the Company's anti-von Willebrand factor (vWF) Nanobody® being developed for the treatment of acquired thrombotic thrombocytopenic purpura (aTTP). These new data relate to additional pre-specified secondary endpoints and demonstrate that treatment with caplacizumab resulted in a clinically meaningful reduction in the use of PEX and length of stay in the ICU and the hospital.

The number of days of PEX during the overall treatment period was 38% lower in the caplacizumab group compared to the placebo arm (5.8 days versus 9.4 days) resulting in a 41% reduction in the volume of plasma used (21.3L on caplacizumab compared to 35.9L in the placebo group). For those patients admitted to the ICU, the number of days in intensive care was reduced by 65% for patients treated with caplacizumab compared to placebo (3.4 days versus 9.7 days, respectively). The overall duration of hospitalisation in the caplacizumab group was reduced by 31% compared to the placebo group (9.9 days versus 14.4 days, respectively).

The data were presented today by Professor Marie Scully of the University College London Hospitals, an investigator in the HERCULES trial, as part of the late-breaking abstracts session at the 59th Annual Meeting of the American Society of Hematology (ASH) in Atlanta, GA, USA. The presentation is available on the Ablynx website under Events & Presentations.

Dr Robert K. Zeldin, Chief Medical Officer at Ablynx, commented:

"The reduced use of plasma exchange and shorter time in the ICU and hospital further demonstrate the potential positive impact of caplacizumab on the quality of life of patients with aTTP, together with providing the opportunity for considerable cost savings. These data build on the previously reported topline results which demonstrated that patients treated with caplacizumab experienced a faster resolution of their acute aTTP episode with a significantly shorter time to platelet count response and a significant reduction in recurrences."

"These efficacy data together with caplacizumab's safety profile demonstrate that it has the potential to address the high unmet medical need in the treatment of aTTP and to have an important impact on the lives of affected patients. We look forward to working together with regulatory authorities to make caplacizumab available for patients suffering from this devastating disease."

Investor conference call and webcast information

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