The Development of Ofatumumab, a Fully Human Anti-CD20 Monoclonal Antibody for Practical Use in Relapsing Multiple Sclerosis Treatment.

The importance of B cells in multiple sclerosis (MS) has been demonstrated through the advent of B-cell-depleting anti-CD20 antibody therapies. Ofatumumab is the first fully human anti-CD20 monoclonal antibody (mAb) developed and tested for subcutaneous (SC) self-administration at monthly doses of 20 mg, and has been approved in the US, UK, EU, and other regions and countries worldwide for the treatment of relapsing MS. The development goal of ofatumumab was to obtain a highly efficacious anti-CD20 therapy, with a safety and tolerability profile that allows for self-administration by MS patients at home and a positive benefit-risk balance for use in the broad relapsing MS population. This development goal was enabled by the unique binding site, higher affinity to B cells, and higher potency of ofatumumab compared to previous anti-CD20 mAbs; these properties of ofatumumab facilitate rapid B-cell depletion and maintenance with a low dose at a low injection volume (20 mg/0.4 ml). The high potency in turn enables the selective targeting of B cells that reside in the lymphatic system via subcutaneous (SC) administration. Through a comprehensive dose-finding program in two phase 2 studies (one intravenous and one SC) and model simulations, it was found that safety and tolerability can be further improved, and the risk of systemic injection-related reactions (IRRs) minimized, by avoiding doses ≥ 30 mg, and by reaching initial and rapid B-cell depletion via stepwise weekly administration of ofatumumab at Weeks 0, 1, and 2 (instead of a single high dose). Once near-complete B-cell depletion is reached, it can be maintained by monthly doses of 20 mg/0.4 ml. Indeed, in phase 3 trials (ASCLEPIOS I/II), rapid and sustained near-complete B-cell depletion (largely independent of body weight, race and other factors) was observed with this dosing regimen, which resulted in superior efficacy of ofatumumab versus teriflunomide on relapse rates, disability worsening, neuronal injury (serum neurofilament light chain), and imaging outcomes. Likely due to its fully human nature, ofatumumab has a low immunogenic risk profile-only 2 of 914 patients receiving ofatumumab in ASCLEPIOS I/II developed anti-drug antibodies-and this may also underlie the infrequent IRRs (20% with ofatumumab vs. 15% with the placebo injection in the teriflunomide arm) that were mostly (99.8%) mild to moderate in severity. The overall rates of infections and serious infections in patients treated with ofatumumab were similar to those in patients treated with teriflunomide (51.6% vs. 52.7% and 2.5% vs. 1.8%, respectively). The benefit-risk profile of ofatumumab was favorable compared to teriflunomide in the broad RMS population, and also in the predefined subgroups of both recently diagnosed and/or treatment-naïve patients, as well as previously disease-modifying therapy-treated patients. Interim data from the ongoing extension study (ALITHIOS) have shown that long-term treatment with ofatumumab up to 4 years is well-tolerated in RMS patients, with no new safety risks identified. In parallel to the phase 3 trials in which SC administration was carried out with a pre-filled syringe, an autoinjector pen for more convenient self-administration of the ofatumumab 20 mg dose was developed and is available for use in clinical practice.

Effect of ofatumumab versus placebo in relapsing multiple sclerosis patients from Japan and Russia: Phase 2 APOLITOS study.

BACKGROUND: Ofatumumab, the first fully human anti-CD20 monoclonal antibody, has been developed as a treatment for relapsing multiple sclerosis (RMS) which can be self-administered at home. OBJECTIVE: To investigate the efficacy and safety of ofatumumab in RMS patients from Japan and Russia. METHODS: APOLITOS included a 24-week, double-blind, placebo-controlled core-part followed by an open-label extension-part. Patients were randomized (2:1) to subcutaneous ofatumumab 20 mg or placebo. Primary outcome was the number of gadolinium-enhancing (Gd+) T1 lesions per scan over 24 weeks. RESULTS: Sixty-four patients were randomized (ofatumumab, n = 43; placebo, n = 21). Primary endpoint was met; ofatumumab reduced Gd + T1 lesions versus placebo by 93.6% (p < 0.001) and the results were consistent across regions (Japan/Russia). Ofatumumab reduced annualized T2 lesion and relapse rate versus placebo by week 24. Both groups showed benefit from ofatumumab in the extension-part. Incidence of adverse events was lower with ofatumumab versus placebo (69.8% vs 81.0%); injection-related reactions were most common. No deaths, opportunistic infections, or malignancies were reported. CONCLUSION: Ofatumumab demonstrated superior efficacy versus placebo, with sustained effect through 48 weeks in RMS patients from Japan/Russia. Switching to ofatumumab after 24 weeks led to rapid radiological and clinical benefits. Safety findings were consistent with pivotal trials.

Progressive multifocal leukoencephalopathy after fingolimod treatment.

OBJECTIVE: We describe the characteristics of the 15 patients with fingolimod-associated progressive multifocal leukoencephalopathy (PML) identified from the Novartis data safety base and provide risk estimates for the disorder. METHODS: The Novartis safety database was searched for PML cases with a data lock point of August 31, 2017. PML classification was based on previously published criteria. The risk and incidence were estimated using the 15 patients with confirmed PML and the overall population of patients treated with fingolimod. RESULTS: As of August 31, 2017, 15 fingolimod-treated patients had developed PML in the absence of natalizumab treatment in the preceding 6 months. Eleven (73%) were women and the mean age was 53 years (median: 53 years). Fourteen of the 15 patients were treated with fingolimod for >2 years. Two patients had confounding medical conditions. Two patients had natalizumab treatment. This included one patient whose last dose of natalizumab was 3 years and 9 months before the diagnosis of PML. The second patient was receiving fingolimod for 4 years and 6 months, which was discontinued to start natalizumab and was diagnosed with PML 3 months after starting natalizumab. Absolute lymphocyte counts were available for 14 of the 15 patients and none exhibited a sustained grade 4 lymphopenia (≤200 cells/µL). CONCLUSIONS: The risk of PML with fingolimod in the absence of prior natalizumab treatment is low. The estimated risk was 0.069 per 1,000 patients (95% confidence interval: 0.039-0.114), and the estimated incidence rate was 3.12 per 100,000 patient-years (95% confidence interval: 1.75-5.15). Neither clinical manifestations nor radiographic features suggested any unique features of fingolimod-associated PML.

Oral fingolimod in primary progressive multiple sclerosis (INFORMS): a phase 3, randomised, double-blind, placebo-controlled trial.

BACKGROUND: No treatments have been approved for primary progressive multiple sclerosis. Fingolimod, an oral sphingosine 1-phosphate receptor modulator, is effective in relapse-onset multiple sclerosis, but has not been assessed in primary progressive multiple sclerosis. We assessed the safety and efficacy of fingolimod in patients with primary progressive multiple sclerosis. METHODS: In INFORMS, a multicentre, double-blind, placebo-controlled parallel-group study, patients with primary progressive multiple sclerosis recruited across 148 centres in 18 countries were randomly allocated (1:1) with computer-generated blocks to receive oral fingolimod or placebo for at least 36 months and a maximum of 5 years. Patients were initially assigned to fingolimod 1·25 mg per day or placebo (cohort 1); however, after a protocol amendment on Nov 19, 2009, patients were switched in a masked manner to fingolimod 0·5 mg, whereas those on placebo continued on matching placebo. From then onwards, patients were assigned to receive fingolimod 0·5 mg/day or placebo (cohort 2). Key inclusion criteria were age 25-65 years, clinical diagnosis of primary progressive multiple sclerosis, 1 year or more of disease progression, and two of the following criteria: positive brain MRI; positive spinal cord MRI; or positive cerebrospinal fluid. Additional eligibility criteria included disease duration of 2-10 years and objective evidence of disability progression in the previous 2 years. Patients and study investigators were masked to group assignment. We used a novel primary composite endpoint based on change from baseline in Expanded Disability Status Scale (EDSS), 25' Timed-Walk Test, or Nine-Hole Peg Test to assess time to 3-month confirmed disability progression in study participants treated for at least 3 years. All randomised patients took at least one dose of study drug. The primary efficacy analysis included all patients in cohort 2 and those assigned to placebo in cohort 1. The safety analysis included all patients in cohorts 1 and 2. This study is registered with ClinicalTrials.gov, number NCT00731692. The study is now closed. FINDINGS: 970 patients were randomly assigned between Sept 3, 2008, and Aug 30, 2011 (147 to fingolimod 1·25 mg and 133 to placebo in cohort 1; 336 to fingolimod 0·5 mg and 354 to placebo in cohort 2). The efficacy analysis set (n=823) consisted of 336 patients randomly allocated to fingolimod 0·5 mg and 487 to placebo. Baseline characteristics were similar across groups and representative of a primary progressive multiple sclerosis population (48% women, mean age 48·5 years [SD 8·4], mean EDSS 4·67 [SD 1·03], 87% free of gadolinium-enhancing lesions). By end of study, 3-month confirmed disability progression had occurred in 232 and 338 patients in the fingolimod and placebo groups, respectively, resulting in Kaplan-Meier estimates of 77·2% (95% CI 71·87-82·51) of patients in the fingolimod group versus 80·3% (73·31-87·25) of patients in the placebo group (risk reduction 5·05%; hazard ratio 0·95, 95% CI 0·80-1·12; p=0·544). Safety results were generally consistent with those of studies of fingolimod in patients with relapse-onset multiple sclerosis. Lymphopenia occurred in 19 (6%) patients in the fingolimod group versus none in the placebo group, bradycardia in five (1%) versus one (<1%), and first-degree atrioventricular block in three (1%) versus six (1%). Serious adverse events occurred in 84 (25%) patients in the fingolimod group and 117 (24%) in the placebo group, including macular oedema in six (2%) versus six (1%), and basal-cell carcinoma in 14 (4%) versus nine (2%). INTERPRETATION: The anti-inflammatory effects of fingolimod did not slow disease progression in primary progressive multiple sclerosis. Therapeutic strategies for primary progressive multiple sclerosis might need different approaches to those used for relapse-onset multiple sclerosis. FUNDING: Novartis Pharma AG.

A case of pathological excitability located with navigated-TMS: presurgical evaluation of focal neocortical epilepsy.

PURPOSE: The quality of presurgical evaluation in focal extratemporal epilepsy surgery is highly dependent on precise structural and functional identification of the epileptic focus. Navigated transcranial magnetic stimulation (nTMS) is a tool that combines the spatial information of high-resolution magnetic resonance imaging (MRI) with the functionality of non-invasive cortical stimulation. The non-invasive character of nTMS suggests that it could be a promising tool for presurgical evaluation of cortical excitability. METHODS: Presurgical nTMS evaluation was performed on an 8-year-old boy with left-sided intractable focal epilepsy, somatosensory auras and epilepsia partialis continua. In line with standardized procedures, motor evoked potentials were sought in both hemispheres over perirolandic cortex during simultaneous belly-tendon surface recordings of the first dorsal interosseus muscles. RESULTS: One singular motor-evoked potential (MEP) could be elicited in the unaffected hemisphere. In contrast, in the affected hemisphere MEPs could be elicited over a large area of the cortex even after the stimulation strength was reduced by at least 44%. Latency stratification in the affected hemisphere differentiated a motor from a sensory region of interest. Stimulation over the sensory region induced a sensory aura. The sensory site was concordant with a previous transient diffusion restriction found in an MRI two years prior to nTMS. CONCLUSIONS: NTMS can locate pathological excitability with high spatial precision. Future studies should compare nTMS with direct cortex stimulation, as well as the combination of nTMS with electroencephalography (EEG) in a larger patient-collective.

Verapamil attenuates the malignant treatment course in recurrent status epilepticus.

In the scenario of refractory status epilepticus, the recommended approach of intensive care treatment is limited with respect to the available pharmacodynamic variability and its impeding, severe side effects. Alternative treatment options are therefore urgently needed. In the case described, a patient with nonlesional frontal lobe epilepsy had a high-frequency series of tonic seizures, which evolved into a malignant form of status epilepticus. Co-administration of verapamil, a potent multidrug transporter inhibitor, was followed by significant reduction in seizure frequency. We discuss the putative role of verapamil and the specific risk factors for this malignant treatment course.

Towards a clinico-pathological classification of granule cell dispersion in human mesial temporal lobe epilepsies.

The dentate gyrus (DG) plays a pivotal role in the functional and anatomical organization of the hippocampus and is involved in learning and memory formation. However, the impact of structural DG abnormalities, i.e., granule cell dispersion (GCD), for hippocampal seizure susceptibility and its association with distinct lesion patterns in epileptic disorders, such as mesial temporal sclerosis (MTS) remains enigmatic and a large spectrum of pathological changes has been recognized. Here, we propose a clinico-pathological classification of DG pathology based on the examination of 96 surgically resected hippocampal specimens obtained from patients with chronic temporal lobe epilepsy (TLE). We observed three different histological patterns. (1) A normal granule cell layer was identified in 11 patients (no-GCP; 18.7%). (2) Substantial granule cell loss was evident in 36 patients (referred to as granule cell pathology (GCP) Type 1; 37.5%). (3) Architectural abnormalities were observed in 49 specimens, including one or more of the following features: granule cell dispersion, ectopic neurons or clusters of neurons in the molecular layer, or bi-lamination (GCP Type 2; 51%). Cell loss was always encountered in this latter cohort. Seventy-eight patients of our present series suffered from MTS (81.3%). Intriguingly, all MTS patients displayed a compromised DG, 31 (40%) with significant cell loss (Type 1) and 47 (60%) with GCD (Type 2). In 18 patients without MTS (18.7%), seven displayed focally restricted DG abnormalities, either cell loss (n = 5) or GCD (n = 2). Clinical histories revealed a significant association between DG pathology patterns and higher age at epilepsy surgery (p = 0.008), longer epilepsy duration (p = 0.004), but also with learning dysfunction (p < 0.05). There was no correlation with the extent of pyramidal cell loss in adjacent hippocampal segments nor with postsurgical seizure relief. The association with long-term seizure histories and cognitive dysfunction is remarkable and may point to a compromised regenerative capacity of the DG in this cohort of TLE patients.