Second University of Naples
Department of Medical, Surgical, Neurological, Metabolic and Aging Science

Author Of 1 Presentation

Disease Modifying Therapies – Risk Management Oral Presentation

FC02.03 - Evaluation of T and B lymphocytopenia in patients treated with Ocrelizumab switching from other treatments compared to naive

Speakers
Presentation Number
FC02.03
Presentation Topic
Disease Modifying Therapies – Risk Management
Lecture Time
13:24 - 13:36

Abstract

Background

Ocrelizumab (Ocre) is an anti-CD20 monoclonal antibody with a known major depleting effect on B cells and marginal on T cells. It is approved for clinical use in highly-active naïve multiple sclerosis (MS) patients and those not responder to previous treatment. In MS patients switching from other drugs prolonged dysfunction of adaptive immune system may occur after discontinuation, posing the need to carefully investigate the safety profile of treatment sequencing.

Objectives

To investigate the B and T cells subsets longitudinal dynamic during treatment with Ocre in patients with MS switching from Fingolimod (FTY) and other treatments (Dimetylfumarate, Interferon Beta, Glatiramer Acetate, Natalizumab, Teriflunomide) compared to naïve patients.

Methods

A multicenter observational 2-year study was conducted in patients starting treatment with Ocre grouped in three arms: naïve (naïve), switching from FTY (pre-FTY), switching from other treatments (other). Data about lymphocyte subtype count (CD3+, CD4+, CD8+ and CD20+) were collected at baseline and every 6 months after starting Ocre. Slope of reduction and proportion of patients with lymphocytes count below the normal lower limit was calculated.

Results

A sample of 135 patients was analysed (37 pre-FTY, 64 other, 34 naïve). At baseline pre-FTY compared to naïve showed significant decrease of CD3+ (1204.54+675.37 cells/mm3 vs 1735.53+653.56, p=0.0003), CD4+ (551.91+254.42 vs 997.03+352.79, p<0.0001), CD8+ (430.38+379.73 vs 537.75+254.34, p=0.027) and CD20+ (88.25+90.94 vs 191.32+149.62, p=0.021) cells. During Ocre the slope of reduction of CD3+ in naïve patients was 5.45 cells/mm3/week (p=0.003). Compared to naïve, the rate of decrease in CD3+ was -1.2 cells/mm3/week in pre-FTY (p=0.087) and +0.19 (p=0.012) in other. The slope of reduction of CD4+ was 2.00 cells/mm3/week in naïve (p=0.072). Compared to naïve the rate of reduction in CD4+ was +0.91 cells/mm3/week in pre-FTY (p=0.061) and +1.70 cells/mm3/week (p=0.012) in other. CD8+ and CD20+ cells decrease was similar among groups (p for interaction between time and treatment = 0.184 and 0.108, respectively). In pre-FTY group compared to baseline the proportion of patients with CD3+ and CD4+ cells lymphopenia was unchanged (16.22% versus 17.14% ; 32.35% versus 34.29%), while the proportion of CD8+ cells was increased (8.82% versus 25.71%).

Conclusions

Our study confirms that Ocre may induce depletion of T cell subsets beyond B cells. Nevertheless, in pre-FTY we also observed a prolonged T- lymphocytopenia , as carry-over effect of the previous therapy. FTY-induced immunosenescence or slow immunoreconstitution may explain this finding.

Collapse

Author Of 1 Presentation

Observational Studies Poster Presentation

P0883 - MRI activity and extended interval of Natalizumab dosing: a multicenter Italian study (ID 1269)

Abstract

Background

Extending the natalizumab interval after the 24th administration could reduce the risk of progressive multifocal leukoencephalopathy (PML) without efficacy reduction.

Objectives

To evaluate the non-inferiority of the efficacy of an extended interval dosing (EID) regimen compared with the standard interval dosing (SID) of natalizumab regarding the multiple sclerosis (MS) MRI activity.

Methods

It is an observational, multicenter (14 Italian centers), retrospective cohort study, starting from the 24th natalizumab infusion to the loss of follow-up or 2 years after baseline. Patients were grouped in 2 categories according to the mean number of weeks between doses: < 5 weeks, SID; ≥ 5 weeks, EID. Three hundred and eight patients were enrolled. Median dose interval (MDI) following 24th infusion was 5 weeks, with a bimodal distribution (modes at 4 and 6 weeks).

Results

Two hundred and sixteen patients were in the SID group (MDI = 4.4 weeks) and 144 in the EID group (MDI 6 weeks). The risk to develop active lesions on MRI is similar in SID and EID groups during the 6 and 12 months after the 24th natalizumab infusion, respectively 2.98% (95% CI: 0.56-5.40) vs 3.32% (95% CI: 0.00-6.65%) [p=0.88] and 6.65% (95% CI: 3.02-10.29) vs 5.67% (95% CI: 1.76-9.58%) [p=0.73]. The EID regimen does not increase the occurrence of MRI activity after 6 and 12 months.

Conclusions

There is no evidence of a reduced efficacy of natalizumab in an EID setting regarding the MRI activity. This observation confirms previous clinical results and together with the increasing evidence of a reduced risk of PML associated to an EID regimen, supports the need of a bigger randomized study to assess the need to change the standard of the natalizumab dosing schedule, in order to better manage JCV-positive patients after 24 doses of natalizumab.

Collapse