Author Of 2 Presentations
P0363 - Ocrelizumab as exit strategy from natalizumab: results from a clinical series (ID 854)
Natalizumab (NTZ) is a highly effective treatment for relapsing-remitting (RR) multiple sclerosis (MS), but its prolonged use can be associated with an increased risk of progressive multifocal leukoencefalopathy (PML). Therefore, NTZ is mainly interrupted in the context of PML risk management strategy, but its discontinuation can be followed by a marked increase of disease activity. Currently, there is no consensus on either the duration of the washout period, or the best subsequent treatment approach. Few data are available on the use of anti-CD20 monoclonal antibodies (mostly rituximab) after NTZ withdrawal, whereas only a small case series of patients switching to ocrelizumab (OCR) has been published in literature.
To evaluate the effectiveness, tolerability and safety of OCR in a real-world cohort of MS patients switching from NTZ.
Demographic, laboratory, clinical and MRI data were collected in this retrospective, observational study, performed on MS patients attending Parma MS centre (Northern Italy).
23 patients (14 females, mean age 40.4 ± 8.57 years) were analysed during a mean follow-up of 15 months (range 5-34), since NTZ discontinuation. Patients had the following characteristics at OCR start: RR course in 74% and progressive active disease in 26%, mean EDSS 3.1 (1.5-6.5), mean disease duration 11 ± 5.67 years and median number of NTZ infusions 28 (13-122). The reasons for switch included PML concern in 78% of cases and suboptimal response to NTZ in 22%. The majority (83%) of patients was JCV+ and only 6 were treated with NTZ extended interval dosing for ≥18 months. The median washout period was 50 days (41-251); all patients underwent a brain MRI immediately before OCR start. Only 4/23 (17%) and 1/19 (5%) patients experienced clinical relapses (all within the first 6 months of therapy) and MRI activity, respectively. ARR decreased from 0.41 (during NTZ) to 0.18 with OCR. Mild adverse events (mostly infusion reactions, hypogammaglobulinemia and leukopenia) occurred in 74% of cases. No patients discontinued OCR and no PML cases emerged.
OCR is effective and well tolerated in highly active MS patients switching from NTZ. A median 6-week transition period appears reasonably safe to balance the risk of disease reactivation with that of opportunistic infections. Larger datasets are needed to confirm the risk of carryover PML in relationship with the length of washout period.
P0600 - Longitudinal evolution of cortical lesions in an Italian cohort of multiple sclerosis patients (ID 731)
Cortical lesions (CLs) have recently acquired a great relevance in multiple sclerosis (MS), both at diagnosis and during the monitoring of the disease, because of their impact on long-term prognosis. However, there is still limited knowledge about the evolution of CLs in time.
The aim of the present observational study was to investigate, retrospectively, the longitudinal evolution of CLs number in comparison to FLAIR-T2 hyperintense white matter lesions (WMLs) in a cohort of MS patients in a single MS centre.
We included all consecutive patients with a relapse-onset MS referred to MS centre of Parma (Italy) who performed at least two MRI scans including double inversion recovery sequences from 2014 to 2019, collecting demographic, clinical and MRI data.
We included 140 MS patients, 67.9% female, with the following characteristics at first MRI: relapsing-remitting (RR) course in 84.3% and secondary progressive (SP) in 15.7% of cases, mean age 40.1±10.49 years, mean disease duration 169.7±100.75 months, mean EDSS 2.5±1.30, mean number of WMLs 24.8±16.50 and of CLs 2.5±2.87. After a mean follow-up of 51.8±8.32 months we observed a conversion to SP phase in 2.1% and a 3-mo-confirmed EDSS progression in 13.6% of patients, with a mean EDSS of 2.6±1.48 and mean number of relapses of 1.1±1.95. During the follow-up only 3.6% of patients did not take any therapy, while 47.1% and 49.3% were on a first-line and a second-line disease-modifying treatment (DMT), respectively. Occurrence of ≥1 new WML or CL appeared in 37.9% and 12.9% of cases, respectively, with a mean number of new WMLs of 1.8±5.58 and new CLs of 0.2±0.6. New CLs never appeared without concomitant WMLs, but 44.4% of cases with new CLs occurred in patients with 1-2 new WMLs and 26.7% of patients with 1-2 new WMLs had ≥1 new CL. At multivariate analysis the risk of occurrence of new CLs was higher in patients with a higher number of new WMLs at last MRI (OR 1.44, CI95% 1.17-1.78, p=0.001) and lower in those who remained RR (OR 0.04, CI95% 0.002-0.76, p=0.03).
In our cohort we observed an overall low MRI activity, probably related to the high percentage of patients on DMT. New CLs appeared in a small percentage of patients and were strictly related to new WMLs. Nevertheless, they added clinical relevance to a consistent proportion of cases characterised by otherwise minimal MRI activity, with important implications for therapeutic switch.