Patients with multiple sclerosis above age 60 have neurological responses to autologous hematopoietic stem cell transplants similar to younger individuals: A single center experience

Abstract Background: Multiple sclerosis (MS) is an autoimmune disease of the central nervous system, characterized by inflammation, demyelination, and progressive neurodegeneration. Autologous hematopoietic stem cell transplantation (aHSCT) has emerged as a therapeutic option for persons with MS, in which mechanisms involve the elimination of autoreactive lymphocytes and the reconstitution of the immune system. Patients above age 60 have worse outcomes when given aHSCT for other diseases. Objective: To analyze the neurological response of patients with MS who received an aHSCT following the “Mexican method.” Depending on the age of the patients, the primary endpoint was the neurological response according to the change in the expanded disability status scale (EDSS) score after the transplant: a positive response rate (PRR) was defined as either stabilization or decrease in the EDSS score, whereas a negative response referred to an increase in the EDSS. Material and methods: We analyzed MS patients who prospectively received an aHSCT following the “Mexican method.” The method, previously described and registered in ClinicalTrials.govNCT02674217, employs high-dose cyclophosphamide (200 mg/Kg), rituximab 1000 mg, dexamethasone, filgrastim, and MESNA. Results: A total of 1,438 patients were prospectively included in the study, 120 of whom (8.34%) were aged 60 years or older. At baseline, the median EDSS score was 5.0 (IQR 3.0–6.5); at 3 months, it dropped to 4.5 (IQR 2.5–6.0) and 5.0 (IQR 2.5–6.5) at 12 and 24 months, respectively. The overall PRR was 75.3% (77.4% in relapsing remitting MS, 74.7% in primary progressive MS, and 72.7% in secondary progressive MS). When stratified by age, the PRR was 75.2% in patients under 60 years and 76.9% in those aged 60 or older, a non-significant statistical difference (p = 0.64). Age subgroup analysis (<60, 60–65, >65) also revealed a comparable PRR. Regarding early complications, these occurred in 2.1% of patients under 60 years and in 5.8% of patients aged 60 years or older (p= 0.02). Conclusion: The overall PRR of persons with MS, given aHSCT with the “Mexican method,” is 75.1%, and was similar among patients aged 60 years or less. The rate of early complications of the procedure was found to be similar. Accordingly, age above 60 years should not be considered as a reason to deny aHSCT to patients with MS.