Discordant effect of IFN-beta1a therapy on anti-IFN antibodies and thyroid disease development in patients with multiple sclerosis

Antidrug Antibodies Against Biological Treatments for Multiple Sclerosis

The development of antidrug antibodies (ADAs) is a major problem in several recombinant protein therapies used in the treatment of multiple sclerosis (MS). The etiology of ADAs is multifaceted. The predisposition for a breakdown of immune tolerance is probably genetically determined, and many factors may contribute to the immunogenicity, including structural properties, formation of aggregates, and presence of contaminants and impurities from the industrial manufacturing process. ADAs may have a neutralizing capacity and can reduce or abrogate the bioactivity and therapeutic efficacy of the drug and cause safety issues. Interferon (IFN)-β was the first drug approved for the treatment of MS, and-although it is generally recognized that neutralizing antibodies (NAbs) appear and potentially have a negative effect on therapeutic efficacy-the use of routine measurements of NAbs and the interpretation of the presence of NAbs has been debated at length. NAbs appear after 9-18 months of therapy in up to 40% of patients treated with IFNβ, and the frequency and titers of NAbs depend on the IFNβ preparation. Although all pivotal clinical trials of approved IFNβ products in MS exhibited a detrimental effect of NAbs after prolonged therapy, some subsequent studies did not observe clinical effects from NAbs, which led to the claim that NAbs did not matter. However, it is now largely agreed that persistently high titers of NAbs indicate an abrogation of the biological response and, hence, an absence of therapeutic efficacy, and this observation should lead to a change of therapy. Low and medium titers are ambiguous, and treatment decisions should be guided by determination of in vivo messenger RNA myxovirus resistance protein A induction after IFNβ administration and clinical disease activity. During treatment with glatiramer acetate, ADAs occur frequently but do not appear to adversely affect treatment efficacy or result in adverse events. ADAs occur in approximately 5% of patients treated with natalizumab within 6 months of therapy, and persistent NAbs are associated with a lack of efficacy and acute infusion-related reactions and should instigate a change of therapy. When using the anti-CD20 monoclonal antibodies ocrelizumab and ofatumumab in the treatment of MS, it is not necessary to test for NAbs as these occur very infrequently. Alemtuzumab is immunogenic, but routine measurements of ADAs are not recommended as the antibodies in the pivotal 2-year trials at the population level did not influence lymphocyte depletion or repopulation, efficacy, or safety. However, in some individuals, NAbs led to poor lymphocyte depletion.

Antibodies to interferon beta in patients with multiple sclerosis receiving CinnoVex, rebif, and betaferon

Treatment with interferon beta (IFN-β) induces the production of binding antibodies (BAbs) and neutralizing antibodies (NAbs) in patients with multiple sclerosis (MS). NAbs against IFN-β are associated with a loss of IFN-β bioactivity and decreased clinical efficacy of the drug. The objective of this study was to evaluate the incidence and the prevalence of binding antibodies (BAbs) and neutralizing antibodies (NAbs) to IFN-β in MS patients receiving CinnoVex, Rebif, or Betaferon. The presence of BAbs was studied in serum samples from 124 MS patients using one of these IFN-β medications by ELISA. The NAbs against IFN-β were measured in BAb-positive MS patients receiving IFN-β using an MxA gene expression assay (real-time RT-PCR). Of the 124 patients, 36 (29.03%) had BAbs after at least 12 months of IFN-β treatment. The proportion of BAb+ was 38.1% for Betaferon, 21.9% for Rebif, and 26.8% for CinnoVex. Five BAb-positive MS patients were lost to follow-up; thus 31 BAb-positive MS patients were studied for NAbs. NAbs were present in 25 (80.6%) of BAb-positive MS patients receiving IFN-β. In conclusion, the three IFN-β preparations have different degrees of immunogenicity.

Arthritis and bursitis in multiple sclerosis patients treated with interferon‐beta

Interferon-beta (IFN-beta) is a type I interferon used in the management of multiple sclerosis. Therapy with IFN-beta has rarely been associated with the development of autoimmune disorders. We present the cases of two female patients diagnosed with relapsing-remitting multiple sclerosis (RRMS) who developed inflammatory musculoskeletal manifestations, following IFN-beta therapy. The first patient developed a monoarthritis 2 weeks after initiation of IFN-beta, which persisted during the 14 months of therapy and resolved with discontinuation of the medication. The second patient developed both autoimmune thyroid disease and a refractory pre-patellar bursitis after 50 months of IFN-beta therapy. Our literature review revealed an additional six cases of onset of inflammatory arthritis in MS patients receiving IFN-beta. We review these reports with comparison to our two cases. The role of IFN-beta in inflammatory musculoskeletal disease is unclear. The potential autoimmune complications of this therapeutic agent should be comprehended when monitoring patients receiving such treatment.

Are individuals with an autoimmune disease at higher risk of a second autoimmune disorder?

Limited evidence suggests that autoimmune diseases tend to co-occur, although data are needed to determine whether individuals with an existing autoimmune disorder are at increased risk of a second disorder. The authors conducted a series of population-based cohort studies, utilizing the United Kingdom General Practice Research Database, to assess intraindividual risks of coexistence of rheumatoid arthritis (RA), autoimmune thyroiditis (AIT), multiple sclerosis (MS), and insulin-dependent diabetes mellitus (IDDM) during 1990-1999. Sex-specific age- and calendar-period standardized incidence ratios (SIRs) were calculated for development of a second autoimmune disease among index populations including 22,888 RA, 26,198 AIT, 4,332 MS, and 6,170 IDDM patients compared with the general population. Among those with IDDM, adjusted AIT rates were higher than expected for both males (SIR = 646.0, 95% confidence interval (CI): 466, 873) and females (SIR = 409.6, 95% CI: 343, 485), as were RA rates for females (SIR = 181.6, 95% CI: 136, 238). Coexistence of AIT and RA was also shown for either disease sequence (sex-specific SIRs = 130.4-162.0). However, point estimates suggested an inverse relation between RA and MS, irrespective of diagnostic sequence. This study demonstrates coexistence of RA, AIT, and IDDM at higher than expected rates but reduced comorbidity between RA and MS.

Identification of interferon-beta antibodies in a reference laboratory setting: Findings for 1144 consecutive sera

Clinical studies demonstrate differences in interferon-beta (IFNbeta) antibody detection frequencies among multiple sclerosis patients receiving different IFNbeta products. We sought to determine if these differences are also found when IFNbeta antibodies are measured in a reference laboratory, where factors normally controlled in clinical studies are unknown. Serum IFNbeta binding antibodies (BAbs) were quantitated by ELISA; BAbs-positive samples were then tested in a bioassay for neutralizing antibodies (NAbs). Consistent with clinical studies, frequencies of BAbs-positive sera and NAbs-positive sera were lower in the Avonex (IFNbeta-1a) treatment group than Rebif (IFNbeta-1a) and Betaseron (IFNbeta-1b) groups. We further identified a predictive relationship between positive BAbs levels and NAbs activity in patients treated with IFNbeta-1a products, but not those treated with IFNbeta-1b.

Remnant epitopes, autoimmunity and glycosylation

The role of extracellular proteolysis in innate and adaptive immunity and the interplay between cytokines, chemokines and proteinases are gradually becoming recognized as critical factors in autoimmune processes. Many of the involved proteinases, including those of the plasminogen activator and matrix metalloproteinase cascades, and also several cytokines and chemokines, are glycoproteins. The stability, interactions with inhibitors or receptors, and activities of these molecules are fine-controlled by glycosylation. We studied gelatinase B or matrix metalloproteinase-9 (MMP-9) as a glycosylated enzyme involved in autoimmunity. In the joints of rheumatoid arthritis patients, CXC chemokines, such as interleukin-8/CXCL8, recruit and activate neutrophils to secrete prestored neutrophil collagenase/MMP-8 and gelatinase B/MMP-9. Gelatinase B potentiates interleukin-8 at least tenfold and thus enhances neutrophil and lymphocyte influxes to the joints. When cartilage collagen type II is cleaved at a unique site by one of several collagenases (MMP-1, MMP-8 or MMP-13), it becomes a substrate of gelatinase B. Human gelatinase B cleaves the resulting two large collagen fragments into at least 33 peptides of which two have been shown to be immunodominant, i.e., to elicit activation and proliferation of autoimmune T cells. One of these two remnant epitopes contains a glycan which is important for its immunoreactivity. In addition to the role of gelatinase B as a regulator in adaptive immune processes, we have also demonstrated that it destroys interferon-beta, a typical innate immunity effector molecule and therapeutic cytokine in multiple sclerosis. Furthermore, glycosylated interferon-beta, expressed in Chinese hamster ovary cells, was more resistant to this proteolysis than recombinant interferon-beta from bacteria. These data not only prove that glycosylation of proteins is mechanistically important in the pathogenesis of autoimmune diseases, but also show that targeting of glycosylated proteinases or the use of glycosylated cytokines seems also critical for the treatment of autoimmune diseases.

Guidelines on use of anti-IFN-beta antibody measurements in multiple sclerosis: report of an EFNS Task Force on IFN-beta antibodies in multiple sclerosis

Therapy-induced binding and neutralizing antibodies is a major problem in interferon (IFN)-beta treatment of multiple sclerosis. The objective of this study was to provide guidelines outlining the methods and clinical use of the measurements of binding and neutralizing antibodies. Systematic search of the Medline database for available publications on binding and neutralizing antibodies was undertaken. Appropriate publications were reviewed by one or more of the task force members. Grading of evidence and recommendations was based on consensus by all task force members. Measurements of binding antibodies are recommended for IFN-beta antibody screening before performing a neutralizing antibody (NAB) assay (Level A recommendation). Measurement of NABs should be performed in specialized laboratories with a validated cytopathic effect assay or MxA production assay using serial dilution of the test sera. The NAB titre should be calculated using the Kawade formula (Level A recommendation). Tests for the presence of NABs should be performed in all patients at 12 and 24 months of therapy (Level A recommendation). In patients who remain NAB-negative during this period measurements of NABs can be discontinued (Level B recommendation). In patient with NABs, measurements should be repeated, and therapy with IFN-beta should be discontinued in patients with high titres of NABs sustained at repeated measurements with 3- to 6-month intervals (Level A recommendation).

Long-term follow-up of 106 multiple sclerosis patients undergoing interferon-beta 1a or 1b therapy: predictive factors of thyroid disease development and duration

BACKGROUND

Conflicting data have been reported on the association between interferon (IFN)-beta therapy of multiple sclerosis (MS) patients and thyroid disease development.

AIMS

The goals of this study are as follows: to assess the actual occurrence of thyroid dysfunction and autoimmunity during long-term IFN-beta therapy; to establish the possible presence of predictive factors for thyroid dysfunction development and duration; and to suggest an effective follow-up protocol for patients receiving long-term IFN-beta therapy.

STUDY PROTOCOL

A total of 106 MS patients (76 women) underwent IFN-beta 1a or 1b therapy for up to 84 months (median, 42 months). Thyroid function and autoimmunity were assessed at baseline and every 3-6 months throughout the treatment course.

RESULTS

Baseline thyroid autoimmunity was detected in 8.5% of patients and hypothyroidism in 2.8%. Thyroid dysfunction (80% hypothyroidism, 92% subclinical, 56% transient) developed in 24% (68% with autoimmunity) of patients and autoimmunity in 22.7% (45.5% with dysfunction), without significant differences between the two cytokines; 68% of dysfunctions occurred within the first year. Autoimmunity emerged as the only predictive factor for dysfunction development (relative risk, 8.9), whereas sustained disease was significantly associated with male gender (P < 0.003).

CONCLUSIONS

Both incident thyroid autoimmunity and dysfunction frequently occur in MS patients during IFN-beta therapy, particularly within the first year of treatment. Thyroid dysfunction is generally subclinical and transient in over than half of cases; preexisting or incident autoimmunity emerged as the only significant predictive factor for thyroid dysfunction development. Thyroid function and autoimmunity assessment is mandatory within the first year of IFN-beta therapy; thereafter, serum TSH measurement only in patients with thyroid disease could be sufficient.