AIIMS November 2011 – MCQ 21

Which is the drug effective in improving EDSS in multiple sclerosis?
A. Interferon beta 1a
B. Interferon beta 1b
C. Glatiramer acetate
D. Natalizumab

Correct answer : D. Natalizumab

Seven drugs are approved as Disease-Modifying Therapies for Relapsing Forms of multiple sclerosis by the U.S. Food and Drug Administration (FDA): (1) IFN–1a (Avonex), (2) IFN–1a (Rebif), (3) IFN–1b (Betaseron), (4) glatiramer acetate (Copaxone), (5) natalizumab (Tysabri), (6) fingolimod (Gilenya), and (7) mitoxantrone (Novantrone). An eighth, cladribine (Leustatin), is currently awaiting an FDA decision on its approval.

The Expanded Disability Status Score (EDSS) is a useful measure of neurologic impairment in Multiple sclerosis.

–IFN beta reduces the attack rate and improves disease severity measures such as EDSS progression and MRI-documented disease burden.
–Glatiramer acetate reduces the attack rate (whether measured clinically or by MRI) in RRMS. Glatiramer acetate may also benefit disease severity measures, although this is less well established than for the relapse rate.
–Natalizumab greatly reduces the attack rate and significantly improves all measures of disease severity in MS.

From this we can conclude that all the above drugs can improve EDSS. But according to Table 380-6, the change in disease severity over a 2 year period is as follows:

Natalizumab, 300 mg IV qmo – (–42%)
Interferon beta 1b, 250 μg SC qod – (–29%)
Interferon beta 1a, 30 μg IM qw – (–37%)
Glatiramer acetate, 20 mg SC qd – (–12%)

Natlizumab has the maximum decrease in disease severity. So we can take it as the best answer.

The above statements are quoted from Harrison – 18th edition.

If you have any better explanation / alternate answer for this question, please post it as a comment below. Thanks!