Antigen-specific tolerance by autologous myelin peptide-coupled cells: a phase 1 trial in multiple sclerosis

Abstract

Multiple sclerosis (MS) is a devastating inflammatory disease of the brain and spinal cord that is thought to result from an autoimmune attack directed against antigens in the central nervous system. The aim of this first-in-man trial was to assess the feasibility, safety, and tolerability of a tolerization regimen in MS patients that uses a single infusion of autologous peripheral blood mononuclear cells chemically coupled with seven myelin peptides (MOG1-20, MOG35-55, MBP13-32, MBP83-99, MBP111-129, MBP146-170, and PLP139-154). An open-label, single-center, dose-escalation study was performed in seven relapsing-remitting and two secondary progressive MS patients who were off-treatment for standard therapies. All patients had to show T cell reactivity against at least one of the myelin peptides used in the trial. Neurological, magnetic resonance imaging, laboratory, and immunological examinations were performed to assess the safety, tolerability, and in vivo mechanisms of action of this regimen. Administration of antigen-coupled cells was feasible, had a favorable safety profile, and was well tolerated in MS patients. Patients receiving the higher doses (>1 × 10(9)) of peptide-coupled cells had a decrease in antigen-specific T cell responses after peptide-coupled cell therapy. In summary, this first-in-man clinical trial of autologous peptide-coupled cells in MS patients establishes the feasibility and indicates good tolerability and safety of this therapeutic approach.

Conflict of interest statement

Competing interests: A.L., S.D.M., and R.M. are listed as co-inventors on a University Medical Center Hamburg-Eppendorf patent (EP# 08845159.6: Use of modified cells for the treatment of multiple sclerosis) related to the use of antigen-coupled cells in MS. The other authors declare that they have no competing interests.

Figures

Fig. 1. Study design

(A) The first six patients were followed before treatment with two clinical, MRI, and laboratory examinations at month −1 before treatment and day 0 and after treatment at weeks 2 and 6 and 3 months. Vital signs and AEs were recorded during infusion; 30 min, 1 hour, 2 hours, and 4 hours after infusion; and on day +1, day +3, week +2, week +3, week +6, and month +3. General physical examination was performed at month −1 and day +1. Neurological examination was done at month −1, day −1, week +2, week +6, and month +3. Brain MRI was assessed at month −1, day −1, week +2, week +6, and month +3. MSIS29 was assessed at month −1, day +1, week +6, and month +3. Patients were further followed for AEs, serious AEs (SAEs), and clinical and MRI disease activity at months +4, +5, and +6. The last three patients were followed at four time points (month −3 to day 0) before treatment, and further examinations were performed at week 2 and months 1, 2, 3, and 6 (scattered lines). (B) Patients were admitted to the phase 1 unit the day before treatment. At day 0, leukapheresis was performed. The autologous cell product manufactured was infused the same day, and patients were monitored for AEs for 24 hours. (C) Most important steps of the manufacturing process, which was performed in blood bags while maintaining a closed system. Erythrocytes are lysed with lysis buffer. The peptides are added, and the coupling procedure is initiated by addition of EDC. After quality control (QC), the ETIMS cell product is used for therapy. * includes washing steps and cell counting. RBCs, red blood cells.

Fig. 2. Peripheral blood cell counts after ETIMS treatment

Absolute peripheral blood counts (means ± SEM) of eosinophils, basophils, neutrophils, lymphocytes, monocytes, and platelets before and after treatment. Dotted lines indicate the time point of study drug administration.

Fig. 3. Clinical exacerbations after ETIMS treatment

Clinical exacerbations in the year before treatment (gray circles), during the first 3 months after treatment (black circles), and during the safety follow-up until month 6 for the nine patients included in the trial. Dose of ETIMS is shown on the right side. Dotted lines indicate the time point of study drug administration.

Fig. 4. Neurologic function after ETIMS treatment

EDSS (left graphs), SNRS (middle graphs), and MSIS29 (right graphs) in patients 1 to 6 (upper graphs; means ± SEM) and in patients 7, 8, and 10 (lower graphs) before and after treatment. Dotted lines indicate the time point of study drug administration.

Fig. 5. New T2 lesions and CELs after ETIMS treatment

New T2 lesions (left graphs) and CELs (right graphs) in patients 1 to 6 (upper graphs; means ± SEM) and in patients 7, 8, and 10 (lower graphs). T2 lesion graphs: y axis is number of T2 lesions; first column in gray indicates the number of total T2 lesions 3 months before study drug administration; columns in black indicate new T2 lesions before and after treatment. CEL graphs: y axis is number of new CELs (both brain and spinal cord CELs); new CELs before and after treatment are shown. Dotted lines indicate the time point of study drug administration.

Fig. 6. Immune cell subsets after ETIMS treatment

(A to C) Percentage of (A) B cells (CD45+CD19+), monocytes (CD45+CD14+), T cells (CD45+CD3+CD56−), NK cells (CD45+CD3−CD56+), and NK T cells (CD45+CD3+CD56+); (B) CD4+ T cells (CD3+CD4+CD8−), including TH1 (CD4+IFN-γ+), TH17 (CD4+IL-17+), TH2 (CD4+IL-4+), Tregs (CD4+FoxP3+), and Tr1 (CD4+IL-10+); and (C) CD8+ T cells (CD3+CD4+CD8+), including regulatory CD8+ (CD8+CD57+ILT2+) and proinflammatory CD8+ (CD8+CD161high) measured by flow-cytometry in patients 6, 7, 8, and 10 before (month −1) and after (month 3) ETIMS treatment. Means ± SEM is shown. Dotted lines indicate the time point of study drug administration.

Fig. 7. Myelin-specific T cell response after ETIMS treatment

MOG1–20, MOG35–55, MBP13–32, MBP83–99, MBP111–129, MBP146–170, PLP139–154, tetanus toxoid (TTx)–specific T cell responses, and unstimulated wells before and 3 months after ETIMS treatment in patients treated with low (1 × 103 to 5 × 108, patients 1 to 5; left panel) or high (1 × 109 to 3 × 109, patients 6, 7, 8, and 10; right panel) dose of antigen-coupled cells. Proliferative responses were measured by [3H]thymidine incorporation assay. Graphs (y axis) represent the scintillation counts per minute (CPM). The dotted lines represent the threshold set for the mean + 3 SDs of unstimulated wells. All wells above this threshold are shown in red.