Jeffrey Palmer

Alemtuzumab more effective than interferon β-1a at 5-year follow-up of CAMMS223 Clinical Trial

Objective: To report the long-term safety and efficacy results from CAMMS223 comparing alemtuzumab with interferon β-1a in early, active relapsing-remitting multiple sclerosis (RRMS). What are the long-term effects of alemtuzumab treatment, received 36 to 48 months previously, on relapse and disability in early, active RRMS? This study provides evidence of the effectiveness of alemtuzumab in reducing the relapse rate and accumulation of disability compared with interferon β-1a (IFNβ-1a) through extended follow-up (up to 60 months from baseline). Methods: Of 334 patients originally randomized, 198 participated in the extension phase (151 [68%] alemtuzumab and 47 [42%] IFNβ-1a). Disability, relapses, and safety were assessed as in the original study period. Efficacy outcomes were analyzed from baseline of the original trial period to 60 months. Safety data extended beyond 60 months. Results: Over 5 years, alemtuzumab lowered the risk of sustained accumulation of disability by 72% and the rate of relapse by 69% compared with IFNβ-1a (both p < 0.0001). The annualized relapse rate from baseline to month 60 was 0.11 for alemtuzumab and 0.35 for IFNβ-1a. Complete safety follow-up reflected 988 and 376 person-years for alemtuzumab and IFNβ-1a patients, respectively. Serious infections were seen in 7% of alemtuzumab patients and 3% of IFNβ-1a patients, and thyroid disorders were seen in 30% of alemtuzumab patients vs 4% of IFNβ-1a patients. Immune thrombocytopenia occurred in 3% of alemtuzumab patients and 0.9% of IFNβ-1a patients during the initial study period; no additional events were reported during the extension phase. One alemtuzumab patient developed Goodpasture disease 39 months after the second annual cycle of alemtuzumab. Conclusions: Through extended follow-up, alemtuzumab remained significantly more efficacious than IFNβ-1a, with a safety profile consistent with previous reports. Classification of Evidence: This study provides Class III evidence that alemtuzumab is more effective than interferon β-1a in reducing relapses and disability in patients with RRMS in a long-term follow-up of a rater-blinded, randomized clinical trial with 59.5% of patients participating in the extended follow-up period.

Improvement in disability after alemtuzumab treatment of multiple sclerosis is associated with neuroprotective autoimmunity

Treatment of early relapsing-remitting multiple sclerosis with the lymphocyte-depleting humanized monoclonal antibody alemtuzumab (Campath [registered trade mark]) significantly reduced the risk of relapse and accumulation of disability compared with interferon β-1a in a phase 2 trial [Coles et al., (Alemtuzumab vs. interferon β-1a in early multiple sclerosis. N Engl J Med 2008; 359: 1786-801)]. Patients treated with alemtuzumab experienced an improvement in disability at 6 months that was sustained for at least 3 years. In contrast, those treated with interferon β-1a steadily accumulated disability. Here, by post hoc subgroup analyses of the CAMMS223 trial, we show that among participants with no clinical disease activity immediately before treatment, or any clinical or radiological disease activity on-trial, disability improved after alemtuzumab but not following interferon β-1a. This suggests that disability improvement after alemtuzumab is not solely attributable to its anti-inflammatory effect. So we hypothesized that lymphocytes, reconstituting after alemtuzumab, permit or promote brain repair. Here we show that after alemtuzumab, and only when specifically stimulated with myelin basic protein, peripheral blood mononuclear cell cultures produced increased concentrations of brain-derived neurotrophic factor, platelet-derived growth factor and ciliary neurotrophic factor. Analysis by reverse transcriptase polymerase chain reaction of cell separations showed that the increased production of ciliary neurotrophic factor and brain-derived neurotrophic factor after alemtuzumab is attributable to increased production by T cells. Media from these post-alemtuzumab peripheral blood mononuclear cell cultures promoted survival of rat neurones and increased axonal length in vitro, effects that were partially reversed by neutralizing antibodies against brain-derived nerve growth factor and ciliary neurotrophic factor. This conditioned media also enhanced oligodendrocyte precursor cell survival, maturation and myelination. Taken together, the clinical analyses and laboratory findings support the interpretation that improvement in disability after alemtuzumab may result, in part, from neuroprotection associated with increased lymphocytic delivery of neurotrophins to the central nervous system.

Alemtuzumab versus interferon beta-1a in early relapsing-remitting multiple sclerosis: post-hoc and subset analyses of clinical efficacy outcomes

BACKGROUND Alemtuzumab is a humanised monoclonal antibody that depletes lymphocytes, causing long-term immunomodulation. In a 3-year, rater-blinded phase 2 study (the CAMMS223 study) in patients with relapsing-remitting multiple sclerosis (RRMS), alemtuzumab reduced relapse rate and the risk of sustained accumulation of disability compared with subcutaneous interferon beta-1a, and the mean expanded disability status scale (EDSS) score of the alemtuzumab cohort improved compared with baseline. Adverse events included infusion-associated reactions, predominantly mild to moderate infections, thyroid disorders, and immune thrombocytopenia. In this study, we further analysed the CAMMS223 data with the aim of determining whether demographic and baseline disease-related characteristics affect the beneficial effects of alemtuzumab. Additionally, we aimed to describe a new outcome measure in multiple sclerosis research: sustained reduction in disability. METHODS 334 treatment-naive patients with active, early RRMS were randomly assigned in a 1:1:1 ratio to receive interferon beta-1a (44 μg subcutaneously three times per week), or 24 mg per day or 12 mg per day alemtuzumab intravenously for 2 or 3 annual cycles. We analysed freedom from clinical disease activity (CDA; defined as no relapses and no sustained accumulation of disability) and occurrence of sustained reduction in disability (SRD; a ≥1 point decrease on the EDSS sustained for 6 consecutive months for patients with a baseline EDSS ≥2), and analysed efficacy outcomes for subgroups based on age, sex, geographic region, MRI-T1 brain volume, MRI-T2 lesion volume, disease duration, number of previous relapses within 2 years, and EDSS. FINDINGS 322 patients were analysed. 161 of 215 patients treated with alemtuzumab were free of CDA at 36 months (Kaplan-Meier estimate 71·8%, 95% CI 63·1-78·8%) compared with 52 of 107 patients treated with interferon beta-1a (42·6%, 32·4-52·4%; hazard ratio [HR]=0·31, 0·20-0·46; p<0·0001). For the 199 patients with a baseline EDSS score greater than or equal to 2, SRD was more likely (HR=2·61, 1·54-4·43; p=0·0004) among patients treated with alemtuzumab (66 of 133 patients, Kaplan-Meier estimate 51·6%, 95% CI 43·2-60·7%) than patients treated with interferon beta-1a (15 of 66 patients, 27·2%, 17·2-41·4%). All disability and relapse outcomes showed evidence of beneficial effects of alemtuzumab compared with interferon beta-1a across all analysed patient subsets, and no subgroup of patients consistently responded better than others to alemtuzumab. INTERPRETATION Alemtuzumab reduced disease activity compared with interferon beta-1a in most of the analysed subgroups. Significantly greater numbers of patients experienced sustained improvement in disability after treatment with alemtuzumab than interferon beta-1a. The efficacy offered by alemtuzumab is a substantial advance in the treatment of multiple sclerosis. FUNDING Genzyme and Bayer Schering Pharma.

Alemtuzumab improves contrast sensitivity in patients with relapsing–remitting multiple sclerosis

Background: Alemtuzumab is a monoclonal antibody directed against CD52 that depletes T and B lymphocytes. Objective: To evaluate the treatment effect of alemtuzumab on low-contrast vision in relapsing–remitting multiple sclerosis (RRMS) patients. Methods: This was a pre-defined exploratory analysis within a randomized, rater-blinded trial (CAMMS223) that was run at 49 academic medical centers in the US and in Europe. Patients with untreated, early, RRMS (McDonald, n = 334) were randomized 1:1:1 to subcutaneous interferon beta-1a (IFNB-1a), or alemtuzumab 12 mg or 24 mg. Visual contrast sensitivity was measured for each eye at baseline and quarterly, with Pelli-Robson charts. Results: The eyes of patients in the pooled alemtuzumab group (versus IFNB-1a) had a greater than 2-fold higher rate of both 3-month and 6-month sustained visual improvement, of at least 0.3 log units (2 triplets, 6 letters) (At 3 months the hazard ratio (HR) = 2.26; CI = 1.19 to 4.31; P = 0.013; and at 6 months the HR = 2.44; CI =1.16 to 5.15; P = 0.019), and they had a lower risk of 3- and 6-month sustained worsening of at least 0.15 log units (1 triplet, 3 letters) (At 3 months the HR = 0.58; CI = 0.38 to 0.89; P = 0.012; and at 6 months HR = 0.55; CI=0.35 to 0.87; P = 0.010). Over the 36-month study period, the eyes of patients in the pooled alemtuzumab group improved in mean contrast sensitivity to a greater extent than those in the IFNB-1a group (0.080 log units versus 0.038 log units; P = 0.0102). Conclusions: Alemtuzumab was associated with a greater chance of improved contrast sensitivity in patients with RRMS and may delay the worsening of visual function. Contrast sensitivity testing was sensitive to treatment effects, even within an active comparator study design. These results support the validity of low-contrast vision testing as a clinical outcome in MS trials.

Alemtuzumab improves neurological functional systems in treatment-naive relapsing-remitting multiple sclerosis patients

BACKGROUND Individual functional system scores (FSS) of the Expanded Disability Status Scale (EDSS) play a central role in determining the overall EDSS score in patients with early-stage multiple sclerosis (MS). Alemtuzumab treatment improves preexisting disability for many patients; however, it is unknown whether improvement is specific to certain functional systems. OBJECTIVE We assessed the effect of alemtuzumab on individual FSS of the EDSS. METHODS CAMMS223 was a 36-month, rater-blinded, phase 2 trial; treatment-naive patients with active relapsing-remitting MS, EDSS ≤3, and symptom onset within 3 years were randomized to annual courses of alemtuzumab or subcutaneous interferon beta-1a (SC IFNB-1a) 44 μg three times weekly. RESULTS Alemtuzumab-treated patients had improved outcomes versus SC IFNB-1a patients on most FSS at Month 36; the greatest effect occurred for sensory, pyramidal, and cerebellar FSS. Among patients who experienced 6-month sustained accumulation of disability, clinical worsening occurred most frequently in the brainstem and sensory systems. For patients with 6-month sustained reduction in preexisting disability, pyramidal and sensory systems contributed most frequently to clinical improvement. CONCLUSIONS Alemtuzumab demonstrated a broad treatment effect in improving preexisting disability. These findings may influence treatment decisions in patients with early, active relapsing-remitting MS displaying neurological deficits. ClinicalTrials.gov Identifier NCT00050778.

Lymphocyte subset dynamics following alemtuzumab treatment in patients who relapsed on a prior therapy

in vivo analysis. Lymphocyte migration in vitro was evaluated in transwell assays using CD4 T cells purified from anti-muCD52-treated mice. In vivo migration was assessed using an acute CNS inflammation model in which mice were injected intracerebroventricularly with lipopolysaccharide (LPS) following anti-muCD52 treatment. Similarly, migration of innate immune cell subsets was evaluated in a peritonitis model of inflammation, in which animals were injected intraperitoneally with thioglycollate 3 days following anti-muCD52 treatment. The numbers of CNS-infiltrating lymphocytes or peritoneum-infiltrating cells were measured by polychromatic flow cytometry. Results: Immune cells from anti-muCD52-treated mice retained their ability to migrate. In vitro, CD4 T cells were able to migrate in response to SDF-1alpha as efficiently as cells from vehicle-treated animals. In vivo, lymphocytes in anti-muCD52-treated animals were able to migrate into the CNS following local induction of inflammation by LPS. Similarly, innate immune cell migration was not affected by anti-muCD52 treatment, as similar numbers and types of cells were observed in the inflamed peritoneum of anti-muCD52and vehicle-treated animals. Conclusions: These results indicate that following anti-CD52 treatment, immune cells retain their ability to migrate. These findings suggest that anti-CD52 treatment may not compromise immune surveillance, but further studies are required. Study Supported by: Genzyme, a Sanofi company.