To conduct systematic long-term follow-up ( LTFU ) of patients in the Prevention of Relapses and Disability by Interferon beta-1a Subcutaneously in Multiple Sclerosis ( PRISMS ) study to provide up to 8 years of safety , clinical and MRI outcomes on subcutaneous ( s.c. ) interferon ( IFN ) beta-1a in relapsing-remitting multiple sclerosis ( RRMS ) .
