A recent study published in the Neurology demonstrated that rituximab immunotherapy meaningfully improved modified Rankin Scale (mRS) scores in 76.3% of autoimmune limbic encephalitis (ALE) patients whereas 68.8% of them attained a favorable mRS score (0-2), a median of 22.5 months later. Kon Chu and colleagues chose ALE patients who already underwent first-line immunotherapy after symptom onset of a median of 6.8 months (mRS score of 3).
However, symptoms worsened even in 31.3% patients who responded partially to the treatment with mRS score extending to 4, when rituximab was started 12.1 months after symptom onset. The authors found that ALE patients delivered excellent response with mRS score of 2 at the end of a median rituximab treatment cycle of 5 weeks compared to those who did not receive rituximab treatment after first-line immunotherapy. Thus rituximab can be a good choice to treat ALE patients with poor response to first-line immunotherapy since it works efficiently and is well-tolerated regardless of the patient’s autoantibody status.
According to the authors, patients who responded partially to first-line therapy showed greater favorable effects while those receiving and not receiving rituximab, at 88.0% and 83.3%, respectively. In multivariate analysis, the authors found 9.5-fold uplift in mRS improvement associated with partial response to first-line immunotherapy. They believe that first-line immunomodulators and rituximab share some common mechanisms in alleviating autoimmunity. On the other hand, patients who received rituximab after nonresponsive first-line treatment experienced superior outcomes (60%) than those who did not receive rituximab (22.2%).
These findings propelled the authors to propose that rituximab may be considered as a first-line immunotherapy for ALE.