OREANDA-NEWS. Ablynx today announced that its anti-IL-6R Nanobody®, vobarilizumab (ALX-0061), successfully completed a 12 week treatment and assessment period in a Phase IIb monotherapy study in patients with moderately to severely active rheumatoid arthritis (RA) who are intolerant to methotrexate or for whom continued methotrexate treatment is inappropriate. The objective of the study was to explore the efficacy and safety of various dose regimens for vobarilizumab monotherapy to guide further clinical development, and to obtain parallel descriptive information for tocilizumab in the same clinical trial RA population.

The study enrolled 251 subjects in the United States, Europe and South America, who were randomly assigned to one of the three blinded dose groups of subcutaneously (sc) administered vobarilizumab [150 mg every 4 weeks (Q4W), 150 mg every 2 weeks (Q2W), 225 mg every 2 weeks (Q2W)] or open-label sc tocilizumab, with the vast majority (94%) receiving weekly tocilizumab dosing. Subjects were evaluated for efficacy and safety up to week 12 and eligible subjects on vobarilizumab were then invited to enroll in an open-label extension study, with 91% accepting. Subjects who were not eligible to roll over or who did not elect to do so were followed for safety for an additional 12 weeks after the last dosing. Evaluation is ongoing for a minority of these subjects.  

The topline ACR efficacy results demonstrate that vobarilizumab appears to be very effective with less frequent administration than tocilizumab. In addition, based on the change from baseline in the health assessment questionnaire disability score (HAQ-DI), vobarilizumab seems to have a rapid positive impact on patients' physical function. Importantly, vobarilizumab induces either clinical remission or low disease activity (based on DAS28CRP) in up to 60% of patients at week 12.

About the Phase IIb monotherapy study

The objective of this Phase IIb monotherapy study was to explore efficacy and safety for various dose regimens for vobarilizumab monotherapy to guide further clinical development, and to obtain parallel descriptive information for tocilizumab in the same clinical trial RA population. The doses were selected in anticipation of providing active treatment as monotherapy; for this reason no low doses were included.

This randomised Phase IIb RA study consists of 2 parallel segments: a double-blind segment to assess the efficacy and safety of vobarilizumab sc and an open-label segment with tocilizumab sc (with a blinded joint assessor), which is intended to provide parallel efficacy and safety data for tocilizumab in the same RA population.

The study enrolled 251 subjects in the United States, Europe and South America, who were randomly assigned to one of three blinded dose groups of subcutaneously (sc) administered vobarilizumab (150 mg Q4W, 150 mg Q2W, 225 mg Q2W) or to the sc tocilizumab1 dose group.

Subjects were evaluated for efficacy and safety up to week 12 and subjects on vobarilizumab were then invited to enroll into an open-label extension study and 91% accepted. Subjects who were not eligible to roll over or chose not to do so were followed for safety for an additional 12 weeks after the last dosing, with evaluation currently ongoing for a minority of subjects.

The primary endpoint is the ACR20 response at week 12, a broadly accepted clinical response measure to demonstrate reduction in RA signs and symptoms. The secondary endpoints include higher levels of response assessments, documentation of efficacy over time, as well as the effects on the improvement in physical function and health-related quality of life. Other planned assessments include the determination of serum levels of vobarilizumab, biomarkers, safety, tolerability and immunogenicity.

About Ablynx

Ablynx is a biopharmaceutical company engaged in the development of Nanobodies®, proprietary therapeutic proteins based on single-domain antibody fragments, which combine the advantages of conventional antibody drugs with some of the features of small-molecule drugs. Ablynx is dedicated to creating new medicines which will make a real difference to society. Today, the Company has more than 40 proprietary and partnered programmes in development in various therapeutic areas including inflammation, haematology, immuno-oncology, oncology and respiratory disease. The Company has collaborations with multiple pharmaceutical companies including AbbVie, Boehringer Ingelheim, Eddingpharm, Genzyme, Merck & Co., Inc., Merck KGaA, Novartis, Novo Nordisk and Taisho Pharmaceuticals. The Company is headquartered in Ghent, Belgium.