Wendy I. White

Safety profile and clinical activity of sifalimumab, a fully human anti-interferon α monoclonal antibody, in systemic lupus erythematosus: a phase I, multicentre, double-blind randomised study

Background Type I interferons (IFNs) appear to play a central role in disease pathogenesis in systemic lupus erythematosus (SLE), making them potential therapeutic targets. Methods Safety profile, pharmacokinetics, immunogenicity, pharmacodynamics and clinical activity of sifalimumab, an anti-IFNα monoclonal antibody, were assessed in a phase I, multicentre, randomised, double-blind, dose-escalation study with an open-label extension in adults with moderately active SLE. Subjects received one intravenous dose of sifalimumab (n=33 blinded phase, 0.3, 1, 3, 10 or 30 mg/kg; n=17 open-label, 1, 3, 10 or 30 mg/kg) or placebo (n=17). Each phase lasted 84 days. Results Adverse events (AEs) were similar between groups; about 97% of AEs were grade 1 or 2. All grade 3 and 4 AEs and all serious AEs (2 placebo, 1 sifalimumab) were deemed unrelated to the study drug. No increase in viral infections or reactivation was observed. Sifalimumab caused dose-dependent inhibition of type I IFN-induced mRNAs (type I IFN signature) in whole blood and corresponding changes in related proteins in affected skin. Exploratory analyses showed consistent trends toward improvement in disease activity in sifalimumab-treated versus placebo-treated subjects. A lower proportion of sifalimumab-treated subjects required new or increased immunosuppressive treatments (12% vs 41%; p=0.03) and had fewer Systemic Lupus Erythematosus Disease Activity Index flares (3% vs 29%; p=0.014). Conclusions Sifalimumab had a safety profile that supports further clinical development. This trial demonstrated that overexpression of type I IFN signature in SLE is at least partly driven by IFNα, and exploratory analyses suggest that IFNα inhibition may be associated with clinical benefit in SLE. Trial registration number NCT00299819.

A Phase 1 Study of a Recombinant Viruslike Particle Vaccine against Human Papillomavirus Type 11 in Healthy Adult Volunteers

Viruslike particles (VLPs) produced from the L1 protein of several papillomaviruses have induced protection from infection after live challenge in animal models. In the present study, the safety and immunogenicity of a human papillomavirus (HPV)--11 L1 VLP candidate vaccine were measured in a phase 1, dose-finding trial in humans. The vaccine was well tolerated and induced high levels of both binding and neutralizing antibodies. Marked increases in lymphoproliferation to HPV--11 L1 antigens were noted after the second vaccination. In addition, lymphoproliferation was induced after vaccination in peripheral blood mononuclear cells (PBMC) stimulated with heterologous L1 VLP antigens of HPV types 6 and 16. Statistically significant increases in HPV antigen--specific interferon--gamma and interleukin-5 production were measured from PBMC culture supernatants. This candidate HPV VLP vaccine induced robust B and T cell responses, and T cell helper epitopes appear to be conserved across HPV types.

Patients with systemic lupus erythematosus, myositis, rheumatoid arthritis and scleroderma share activation of a common type I interferon pathway

Objective To characterise activation of the type I interferon (IFN) pathway in patients with systemic lupus erythematosus (SLE), dermatomyositis (DM), polymyositis (PM), rheumatoid arthritis (RA) and systemic scleroderma (SSc) and to evaluate the potential to develop a molecular diagnostic tool from the peripheral blood that reflects this activation in disease-affected tissues. Methods Overexpressed transcripts were identified in the whole blood (WB) of 262 patients with SLE, 44 with DM, 33 with PM, 28 with SSc and 89 with RA and compared with 24 healthy subjects using Affymetrix microarrays. A five gene type I IFN signature was assessed in these subjects to identify subpopulations showing both activation and concordance of the type I IFN pathway in the peripheral blood and disease-affected tissues of each disease and to correlate activation of this pathway in the WB with clinical measurements. Results A common set of 36 type I IFN inducible transcripts were identified among the most overexpressed in the WB of all subjects. Significant activation of the type I IFN pathway in subgroups of each of the five diseases studied was observed. Baseline disease activity measurements correlated with a type I IFN gene signature in the WB of subjects with SLE, PM and SSc, as did various serum autoantibody levels in subjects with SLE and DM. This signature was also well correlated between disease-affected tissue and WB in subjects with SLE, DM, PM and SSc. Conclusions The results indicate that the type I IFN pathway is activated in patient subsets of five rheumatic diseases and suggest that these subsets may benefit from anti-IFN therapy.

Sifalimumab, a Human Anti–Interferon‐α Monoclonal Antibody, in Systemic Lupus Erythematosus: A Phase I Randomized, Controlled, Dose‐Escalation Study

Objective To evaluate the safety and tolerability of multiple intravenous (IV) doses of sifalimumab in adults with moderate-to-severe systemic lupus erythematosus (SLE). Methods In this multicenter, double-blind, placebo-controlled, sequential dose-escalation study, patients were randomized 3:1 to receive IV sifalimumab (0.3, 1.0, 3.0, or 10.0 mg/kg) or placebo every 2 weeks to week 26, then followed up for 24 weeks. Safety assessment included recording of treatment-emergent adverse events (AEs) and serious AEs. Pharmacokinetics, immunogenicity, and pharmacodynamics were evaluated, and disease activity was assessed. Results Of 161 patients, 121 received sifalimumab (26 received 0.3 mg/kg; 25, 1.0 mg/kg; 27, 3.0 mg/kg; and 43, 10 mg/kg) and 40 received placebo. Patients were predominantly female (95.7%). At baseline, patients had moderate-to-severe disease activity (mean SLE Disease Activity Index score 11.0), and most (75.2%) had a high type I interferon (IFN) gene signature. In the sifalimumab group versus the placebo group, the incidence of ≥1 treatment-emergent AE was 92.6% versus 95.0%, ≥1 serious AE was 22.3% versus 27.5%, and ≥1 infection was 67.8% versus 62.5%; discontinuations due to AEs occurred in 9.1% versus 7.5%, and death occurred in 3.3% (n = 4) versus 2.5% (n = 1). Serum sifalimumab concentrations increased in a linear and dose-proportional manner. Inhibition of the type I IFN gene signature was sustained during treatment in patients with a high baseline signature. No statistically significant differences in clinical activity (SLEDAI and British Isles Lupus Assessment Group score) between sifalimumab and placebo were observed. However, when adjusted for excess burst steroids, SLEDAI change from baseline showed a positive trend over time. A trend toward normal complement C3 or C4 level at week 26 was seen in the sifalimumab groups compared with baseline. Conclusion The observed safety/tolerability and clinical activity profile of sifalimumab support its continued clinical development for SLE.

Safety profile and clinical activity of multiple subcutaneous doses of MEDI-528, a humanized anti-interleukin-9 monoclonal antibody, in two randomized phase 2a studies in subjects with asthma

BackgroundInterleukin-9 (IL-9)-targeted therapies may offer a novel approach for treating asthmatics. Two randomized placebo-controlled studies were conducted to assess the safety profile and potential efficacy of multiple subcutaneous doses of MEDI-528, a humanized anti-IL-9 monoclonal antibody, in asthmatics.MethodsStudy 1: adults (18-65 years) with mild asthma received MEDI-528 (0.3, 1, 3 mg/kg) or placebo subcutaneously twice weekly for 4 weeks. Study 2: adults (18-50 years) with stable, mild to moderate asthma and exercise-induced bronchoconstriction received 50 mg MEDI-528 or placebo subcutaneously twice weekly for 4 weeks. Adverse events (AEs), pharmacokinetics (PK), immunogenicity, asthma control (including asthma exacerbations), and exercise challenge test were evaluated in study 1, study 2, or both.ResultsIn study 1 (N = 36), MEDI-528 showed linear serum PK; no anti-MEDI-528 antibodies were detected. Asthma control: 1/27 MEDI-528-treated subjects had 1 asthma exacerbation, and 2/9 placebo-treated subjects had a total of 4 asthma exacerbations (one considered a serious AE). In study 2, MEDI-528 (n = 7) elicited a trend in the reduction in mean maximum decrease in FEV1 post-exercise compared to placebo (n = 2) (-6.49% MEDI-528 vs -12.60% placebo; -1.40% vs -20.10%; -5.04% vs -15.20% at study days 28, 56, and 150, respectively). Study 2 was halted prematurely due to a serious AE in an asymptomatic MEDI-528-treated subject who had an abnormal brain magnetic resonance imaging that was found to be an artifact on further evaluation.ConclusionsIn these studies, MEDI-528 showed an acceptable safety profile and findings suggestive of clinical activity that support continued study in subjects with mild to moderate asthma.Trial registrationClinicalTrials (NCT): NCT00507130 and ClinicalTrials (NCT): NCT00590720

Development of Potential Pharmacodynamic and Diagnostic Markers for Anti-IFN-α Monoclonal Antibody Trials in Systemic Lupus Erythematosus.

To identify potential pharmacodynamic biomarkers to guide dose selection in clinical trials using anti-interferon-alpha (IFN-α) monoclonal antibody (mAb) therapy for systemic lupus erythematosus (SLE), we used an Affymetrix human genome array platform and identified 110 IFN-α/β-inducible transcripts significantly upregulated in whole blood (WB) of 41 SLE patients. The overexpression of these genes was confirmed prospectively in 54 additional SLE patients and allowed for the categorization of the SLE patients into groups of high, moderate, and weak overexpressers of IFN-α/β-inducible genes. This approach could potentially allow for an accurate assessment of drug target neutralization in early trials of anti-IFN-α mAb therapy for SLE. Furthermore, ex vivo stimulation of healthy donor peripheral blood mononuclear cells with SLE patient serum and subsequent neutralization with anti-IFN-α mAb or anti-IFN-α receptor mAb showed that anti-IFN-α mAb has comparable effects of neutralizing the overexpression of type I IFN-inducible genes as that of anti-IFNAR mAb. These results suggest that IFN-α, and not other members of type I IFN family in SLE patients, is mainly responsible for the induction of type I IFN-inducible genes in WB of SLE patients. Taken together, these data strengthen the view of IFN-α as a therapeutic target for SLE.

A phase 1b clinical trial evaluating sifalimumab, an anti-IFN-α monoclonal antibody, shows target neutralisation of a type I IFN signature in blood of dermatomyositis and polymyositis patients

Objective To assess the pharmacodynamic effects of sifalimumab, an investigational anti-IFN-α monoclonal antibody, in the blood and muscle of adult dermatomyositis and polymyositis patients by measuring neutralisation of a type I IFN gene signature (IFNGS) following drug exposure. Methods A phase 1b randomised, double-blinded, placebo controlled, dose-escalation, multicentre clinical trial was conducted to evaluate sifalimumab in dermatomyositis or polymyositis patients. Blood and muscle biopsies were procured before and after sifalimumab administration. Selected proteins were measured in patient serum with a multiplex assay, in the muscle using immunohistochemistry, and transcripts were profiled with microarray and quantitative reverse transcriptase PCR assays. A 13-gene IFNGS was used to measure the pharmacological effect of sifalimumab. Results The IFNGS was suppressed by a median of 53–66% across three time points (days 28, 56 and 98) in blood (p=0.019) and 47% at day 98 in muscle specimens post-sifalimumab administration. Both IFN-inducible transcripts and proteins were prevalently suppressed following sifalimumab administration. Patients with 15% or greater improvement from baseline manual muscle testing scores showed greater neutralisation of the IFNGS than patients with less than 15% improvement in both blood and muscle. Pathway/functional analysis of transcripts suppressed by sifalimumab showed that leucocyte infiltration, antigen presentation and immunoglobulin categories were most suppressed by sifalimumab and highly correlated with IFNGS neutralisation in muscle. Conclusions Sifalimumab suppressed the IFNGS in blood and muscle tissue in myositis patients, consistent with this molecules mechanism of action with a positive correlative trend between target neutralisation and clinical improvement. These observations will require confirmation in a larger trial powered to evaluate efficacy.

Antibody and cytotoxic T-lymphocyte responses to a single liposome-associated peptide antigen

The development of peptide-based vaccines that elicit antibody (Ab) and cellular immune responses has been hampered by the lack of highly immunogenic formulations. In this study, we compared the induction of Ab and cytotoxic T-lymphocyte (CTL) responses to a peptide derived from the V3 loop of HIV-1 gp120 (P18 and its cysteine-glycine derivative (CG-P18)) when incorporated into liposomes with lipid A (LA) or mixed with aluminum hydroxide. P18-specific CTL were only observed with liposomes with LA. P18-specific Ab responses were found with liposomes containing CG-P18 but not P18. Increased surface expression of the former, resulted in enhancement of the Ab response without loss of CTL induction. Thus, the manner in which a peptide is localized can influence the outcome of the response induced by highly immunogenic liposome formulations.

Two first-in-human, open-label, phase I dose-escalation safety trials of MEDI-528, a monoclonal antibody against interleukin-9, in healthy adult volunteers

BACKGROUND Interleukin-9 (IL-9) is involved in pathogenic aspects of the asthmatic response, including induction of the proliferation of T-helper type 2 lymphocytes, mucus production, and mast-cell differentiation, proliferation, and recruitment to the lung. In preclinical studies in mice, inhibition of IL-9 through neutralizing monoclonal antibody (mAb) treatment partially reduced airway hyperresponsiveness and mast-cell progenitor migration to the lung. OBJECTIVE The goal of the present studies was to determine the safety and pharmacokinetic profiles and immunogenicity of MEDI-528, a humanized immunoglobulin G1k anti-IL-9 mAb, in healthy adult volunteers. METHODS In separate open-label, Phase I dose-escalation studies, single doses of MEDI-528 0.3, 1.0, 3.0, or 9.0 mg/kg were administered as an intravenous infusion (20 mg/min administered over 1-40 minutes, depending on dose) and by subcutaneous injection. All subjects were followed for 84 days. Any laboratory test value outside the normal reference range was considered an adverse event (AE). RESULTS Twenty-four subjects were enrolled in the intravenous study, and 29 subjects were enrolled in the subcutaneous study. No deaths or serious or severe AEs occurred in either study. The most frequently reported AEs in the intravenous study were laboratory test abnormalities; the most frequently reported AEs in the subcutaneous study were pharyngolaryngeal pain, palpable lymph nodes, and laboratory test abnormalities. The single-dose pharmacokinetics of MEDI-528 were linear and dose proportional over the dose range studied with both routes of administration. The mean t((1/2)) after intravenous administration was approximately 26 days (range, 25-28 days); the mean t((1/2)) after subcutaneous administration ranged from 33 to 87 days across doses. A low titer (1:80) of antibodies to MEDI-528 was detected on day 84 in a single volunteer receiving intravenous MEDI-528 3.0 mg/kg. No antibody titers were detected in any of the volunteers receiving subcutaneous MEDI-528. CONCLUSIONS Administered intravenously or subcutaneously, MEDI-528 had an acceptable safety profile and exhibited linear pharmacokinetics over the dose range studied in healthy adults in these Phase I studies. The findings support further investigation of MEDI-528 in multiple-dose trials in patients with asthma. ClinicalTrials.gov Identification numbers: NCT00192296 (intravenous study); NCT00116168 (subcutaneous study).

A randomized, double-blind, placebo-controlled, phase I study of MEDI-545, an anti–interferon-alfa monoclonal antibody, in subjects with chronic psoriasis

BACKGROUND Interferon-alfa (IFN-alpha) has been implicated in the pathogenesis of psoriasis. OBJECTIVE To evaluate the safety profile of MEDI-545, a fully human anti-IFN-alpha monoclonal antibody and to explore its effect on the involvement of type I IFN-alpha activity in the maintenance of established plaque psoriasis. METHODS We conducted an 18-week, randomized, double-blind, placebo-controlled, dose-escalating study in 36 subjects with chronic plaque psoriasis. Subjects received one intravenous dose of MEDI-545 (0.3-30.0 mg/kg) or placebo. Study outcomes were safety profile, pharmacokinetics, immunogenicity, and clinical effects. RESULTS There was no difference in adverse events between MEDI-545 and placebo. Two serious adverse events were reported; one drug-related hypotensive infusion reaction occurred in one subject in the 30.0 mg/kg MEDI-545 dose group, causing discontinuation of study drug in that subject and study dismissal of the other subjects in the same cohort; and a myocardial infarction occurred in one subject in the 10 mg/kg MEDI-545 dose group, which was considered to be unrelated to treatment. MEDI-545 was nonimmunogenic, had a half-life of 21 days, showed no significant inhibition of the type I IFN gene signature, and had no clinical activity. LIMITATIONS The study addressed only IFN-alpha and chronic psoriatic lesions. CONCLUSION The safety profile of MEDI-545 supports further clinical development. IFN-alpha does not appear to be significantly involved in the maintenance of established plaque psoriasis.