Switch From Fingolimod to Alemtuzumab Might Trigger MS Relapse

Nine patients with relapsing multiple sclerosis had significant and unexpected disease activity within 12 months of switching from fingolimod to alemtuzumab, according to a report from six European neuroscience centers. The report was published January 10 in Neurology: Neuroimmunology & Neuroinflammation.

The centers treated 174 patients with alemtuzumab (Lemtrada); 36 had been on fingolimod (Gilenya) beforehand. “Therefore, these nine patients ... represent 25% of the fingolimod-alemtuzumab cohort,” said Mark Willis, MBBCh, Clinical Research Fellow at Cardiff University, Wales, and colleagues.

The researchers speculated that prolonged sequestration of autoreactive lymphocytes following fingolimod withdrawal allowed “these cells to be concealed from the usual biological effect of alemtuzumab. Subsequent lymphocyte egress then provoke[d] disease reactivation ... This may have important implications for sequential drug selection and washout periods in a subset of patients who switch from fingolimod or drugs with similar biological mechanisms,” they said.

The nine patients were on fingolimod for between five and 33 months, but it was not effective. As a result, they were started on alemtuzumab following a median fingolimod washout period of six weeks. Eight patients had at least one clinical relapse within 12 months of the first alemtuzumab infusion cycle; the median time to relapse following alemtuzumab induction was 4.5 months. All nine patients had radiologic evidence of new disease activity.

Five patients had lymphocyte counts below normal when started on alemtuzumab. It has “been suggested that patients continue on an alternative [disease-modifying treatment] after fingolimod discontinuation, preferably until peripheral lymphocyte counts have normalized.” However, “there is currently no consensus as to which subsequent therapeutic agent is optimal,” the investigators said.

All nine patients went on to the second planned infusion of alemtuzumab; eight were relapse free during a mean follow-up of six months after the second treatment cycle. Of seven patients who had further imaging, four were radiologically stable, three had new T2 lesions, and one had a new gadolinium-enhancing lesion.

—M. Alexander Otto

Suggested Reading

Willis M, Pearson O, Illes Z, et al. An observational study of alemtuzumab following fingolimod for multiple sclerosis. Neurol Neuroimmunol Neuroinflamm. 2017;4(2):e320.