Charlotte Teunissen, PhD, VU University Medical Center Amsterdam, The Netherlands, discusses ongoing work in her group, looking to identify novel treatment response biomarkers for progressive multiple sclerosis (MS). Using Olink technology for multiplex protein biomarker discovery, Prof. Teunissen’s team are analyzing data from patients treated with natalizumab or ocrelizumab, hoping to discover markers that distinguish individuals with persistent progression from those with controlled disease. Prof. Teunissen also discusses work to prepare for the implementation of novel biomarkers, such as defining detailed protocols for contactin 1 and GFAP analysis. This interview took place at the European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS) congress 2021.