after enrolment you are assigned by the study system to one of two groups. each group receives two tablets every day to keep the study blind. one tablet contains the active drug and the other tablet is a placebo.

if you are assigned to the fenebrutinib group you will take one fenebrutinib 400 mg film‑coated tablet and one teriflunomide placebo tablet each day.

if you are assigned to the teriflunomide group you will take one teriflunomide 14 mg film‑coated tablet and one fenebrutinib placebo tablet each day.

on the first day of treatment you undergo a series of examinations that include a physical examination, blood sampling, vital‑sign measurement, electrocardiogram (ecg), and a brain magnetic resonance imaging scan (mri).

the results provide a reference point for later comparison of disease activity and safety.

you take the two tablets orally once each day, preferably at the same time, for the whole study period.

the dosage is fixed: fenebrutinib 400 mg per day or teriflunomide 14 mg per day, depending on the group you were randomised to.

you attend clinic visits at approximately week 4, week 12, week 24, week 36 and week 48.

at each visit blood samples are taken to check safety parameters, vital signs and ecg are recorded, and you complete questionnaires about physical impact of multiple sclerosis.

any adverse events (unwanted effects) are recorded and evaluated.

at week 24 a second brain mri scan is performed to assess new or enlarging lesions and changes in brain volume.

the scan results are compared with the baseline scan to evaluate disease activity.

at week 48 a final brain mri scan is performed together with the last set of blood tests, vital‑sign measurements, ecg and questionnaire assessments.

the data collected at this visit are used to determine the primary outcome (annualised relapse rate) and all secondary outcomes of the study.

after the week 48 visit the study medication is stopped.