Antisense oligonucleotides bind to and inhibit specific mRNA sequences. ATL1102 is an antisense inhibitor of VLA-4 mRNA, thereby inhibiting activated T-cell adhesion to endothelial cells, preventing their migration into the central nervous system. A proofof- concept study demonstrated that 8 weeks of treatment with ATL1102 significantly reduced the cumulative number of new active lesions in patients with RRMS. The results were reported by Volker Limmroth, University of Cologne, Cologne, Germany, and colleagues. Among 74 patients, those randomized to ATL1102 200 mg SC twice weekly had a 54.4% decrease in the cumulative number of new active lesions when compared with the placebo group (P=0.01). Treatment with ATL1102 also reduced the cumulative number of new T1 Gd-enhanced lesions by 66.7% (P=0.002).