The gap between effect of drugs and effectiveness of treatments.

Despite profound effects on the immune system, drugs for multiple sclerosis (MS) therapy have shown only moderate treatment effectiveness. The approved drugs, interferon (IFN)-beta and glatiramer acetate, have a number of effects on the immune system that could interfere with the disease processes in MS but are only able to reduce the relapse rate by 30% and have little or no effect on disease progression. The new targeted immune therapies, campath-1H and natalizumab, have shown immense treatment effectiveness as for inflammation-related disease manifestations, i.e. relapses and MRI activity, but an effect on long-term disease progression has not yet been demonstrated. There are several explanations of the gap between drug effects and treatment effectiveness of which some are related to the properties of the immune system and some are related to the properties of drugs used for treatment of MS. To fill the gap we need to have drugs that both effectively and safely eliminate the inflammation and in addition have neuroprotective properties. However, this may not be obtained from a single drug but may require combinations of drugs with different actions on the disease processes.