<prompt> Which is the only drug effective in improving EDSS in multiple sclerosis?MethotrexateFingolimodGlatiramer acetateNatalizumab  <response>: The statement only drug effective in improving EDSS seems to be wrong because many drugs have shown to reduce disease severity on EDSS scores. Expanded disability status scoreEDSS is a scoring system for MS where high score means worsening neurological dysfunction. Maximum reduction in EDSS is seen in natalizumab group. Ref :Harrisons 18th ed. 