Presentations of clinical trials for new MS drugs take up a large space at the AAN. It must be said somewhat restrictively that real news is rare at this point. Essentially, evaluations of subgroup analyses and the results of long-term extensions of clinical approval studies were presented. Thus, spread over several posters, is the 5-year analysis of the approval studies of alemtuzumab (CARE MS I and II). This analysis shows that the study patients remain stable in terms of relapse rate and disability progression, even though the majority of patients did not receive any further therapy after the end of the controlled study phase. More than 40% of alemtuzumab patients even achieved an improvement in clinical status (P3.022). As expected, this long-term observation also derived that patients benefit from a switch from interferon-beta 1a to alemtuzumab in terms of relapse rate and MRI activity (P3.025).
A small surprise was the presentation of new data on cladribine. Cladribine is an oral substance for the treatment of relapsing MS, which was considered a promising new substance in the past due to a positive phase III study. However, the European Medicines Agency (EMA) had safety concerns and did not grant approval. Now the data from the extension of the CLARITY study is being presented, which prove a positive effect of treatment with cladribine over a total of 4 years (P3.029). In addition, the ONWARD study showed that adding cladribine to a treatment with interferon is beneficial and enhances the effect of the interferons (P3.029). Finally, the ORACLE study – a study on the effect of cladribine in CIS patients – was re-evaluated taking into account the McDonald diagnostic criteria from 2010 (P3.035). Here it was shown that cladribine also has an effect in early MS and significantly prevents further relapses. This renewed presentation of data on cladribine suggests that the manufacturer may try again to bring cladribine to approval.
An interesting new substance is daclizumab (DAC), an antibody directed against the subunit of the IL-2 receptor and thus slows the clonal expansion of T lymphocytes. This substance attracted attention last year through two positive phase III studies (SELECT and DECIDE). This year, only some interesting aspects from the subgroup analyses of these studies are reported. It was shown that the use of DAC leads to an improvement in cognitive performance and was superior to the use of interferon beta-1a. In addition, a detailed analysis of the skin side effects of daclizumab was presented (P2.083). It turned out that most side effects were mild to moderate and about 2% showed severe skin side effects. Life-threatening exfoliative diseases did not occur in the DECIDE study. Most situations could be controlled by the use of steroids.
Several posters dealt with rebound activity after discontinuation of fingolimod (P2.081). The existence of a rebound is often discussed – some experts rather see a return of the previous disease activity. On the other hand, two posters at the AAN argue with a rebound after discontinuation of fingolimod, which occurs 2-3 months after discontinuation of fingolimod, and is more likely to be handled with plasma exchange treatment than with steroids.
A fairly interesting observation was finally communicated by the group of Thomas Berger from Innsbruck (P3.067). They looked at the JCV serostatus in natalizumab over about 6 years and were able to show that the annual conversion rate is relatively low at about 3% and the JCV status was thus relatively stable over the observation period of 6 years.
