Glatiramer Acetate (Copolymer-1) was licensed in the USA in 1996 for the treatment of Relapsing/Remitting Multiple Sclerosis.

In order to assess its efficacy, a meta-analysis of all randomized controlled trials was performed. Two double-blind studies, accounting for a total number of 299 patients, contribute to this analysis.

Patients undergoing the treatment have decreased probability of relapse at 12 months (OR 0.17, 95% CI 0.05-0.51, p = 0.002) and of unsustained progression of Disability at 24 and 35 months (OR 0.57, 95% CI 0.34-0.95, p = 0.031, and OR 0.50, 95% CI 0.28-0.90, p = 0.019).

These data suggest that Glatiramer Acetate represents an alternative to Interferon treatment in Relapsing/Remitting Multiple Sclerosis. However, further evidence of efficacy is required to justify its use in clinical practice.

Copyright 2000 S. Karger AG, Basel

Objective
To evaluate the efficacy of Glatiramer Acetate (GA, Copaxone; Teva Pharmaceutical Industries, Ltd., Petah Tiqva, Israel) by MRI-based measures in patients with Relapsing/Remitting (RR) MS.

Methods
Twenty-seven patients with Clinically Definite RR-MS were treated with either 20 mg of GA by daily subcutaneous self-injection (n = 14) or placebo (n = 13) for approximately 24 months.

Axial dual-echo fast-Spin-Echo T₂-weighted images and T₁-weighted images before and after Gadolinium (Gd) were acquired at 1.5 tesla and transferred into an image processing computer system.

The main outcome measures were the number of Gd-enhanced T₁ and T₂ lesions and their volume as well as Brain Parenchyma volume.

Results
The values of age, disease duration, Expanded Disability Status Scale (EDSS) score, the number of T₁- and T₂-weighted lesions, and their volume were similar between GA- and placebo-receiving groups at the entry of this study.

There was a decrease in the number of T₁-enhanced lesions (p = 0.03) and a significant percent annual decrease of their volume in GA recipients compared with those of placebo recipients.

There were no significant differences between changes in the two groups in the number of T₂ Lesions and their volume.

The loss of Brain tissue was significantly smaller in the GA group compared with that of the placebo group.

Conclusions
These results show that GA treatment may decrease both Lesion Inflammation and the rate of Brain Atrophy in RR-MS.

We examined the effect of Glatiramer Acetate, a random Copolymer of Alanine, Lysine, Glutamic Acid, and Tyrosine, on Antigen-specific T-Cell responses in patients with Multiple Sclerosis (MS).

Glatiramer Acetate (Copaxone) functioned as a universal Antigen, inducing proliferation, independent of any prior exposure to the polymer, in T-Cell lines prepared from MS or healthy subjects.

However, for most patients, daily injections of Glatiramer Acetate abolished this T-Cell response and promoted the secretion of IL-5 and IL-13, which are characteristic of Th2 Cells.

The surviving Glatiramer Acetate-reactive T-Cells exhibited a greater degree of degeneracy as measured by cross-reactive responses to combinatorial Peptide libraries.

Thus, it appears that, in some individuals, in vivo administration of Glatiramer Acetate induces highly cross-reactive T-Cells that secrete Th2 Cytokines.

To our knowledge, Glatiramer Acetate is the first agent that suppresses human AutoImmune Disease and alters Immune function by engaging the T-Cell receptor.

This compound may be useful in a variety of AutoImmune Disorders in which Immune deviation to a Th2 type of response is desirable.

Copolymer-1 (COP), a standardized mixture of synthetic polypeptides consisting of L-Glutamic Acid, L-Lysine, L-Alanine, and L-Tyrosine, has beneficial effects in Multiple Sclerosis and Experimental AutoImmune EncephaloMyelitis.

We selected a panel of 721 COP-reactive T-Cell lines (TCL) from the blood of COP-treated and untreated Multiple Sclerosis patients and from healthy donors by using the split-well cloning technique.

All TCL selected with COP proliferated in response to COP but not to Myelin Basic Protein (MBP). Conversely, 31 control TCL selected with MBP proliferated in response to MBP but not to COP.

We used IntraCellular double-immunofluorescence flow cytometry for quantitative analysis of Cytokine production (IL-4, IFN-γ) by the TCL.

The majority of the COP-reactive TCL from untreated Multiple Sclerosis patients and normal donors predominantly produced IFN-γ and, accordingly, were classified as T-Helper 1 cells (Th1).

In contrast, the majority of the COP-reactive TCL from COP-treated patients predominantly (but not exclusively) produced IL-4-i.e., were Th2 (P < 0.05 as assessed by using a suitable preference intensity index).

Longitudinal analyzes revealed that the Cytokine profile of COP-reactive TCL tends to shift from Th1 to Th2 during treatment.

Interestingly, although there was no proliferative cross-reaction, about 10% of the COP-reactive TCL responded to MBP by secretion of small amounts of IL-4 or IFN-γ, depending on the Cytokine profile of the TCL.

These results are consistent with a protective effect of COP-reactive Th2 Cells.

It is hypothesized that these cells are activated by COP in the periphery, migrate into the Central Nervous System, and produce ImmunoModulatory Cytokines after local recognition of MBP.

This study addresses the issue of the effect of ImmunoModulating therapies in the target organ, the Central Nervous System (CNS), in the case of Multiple Sclerosis.

Copolymer 1 (Cop 1, Copaxone, Glatiramer Acetate), an approved drug for the treatment of Multiple Sclerosis, is a potent inducer of Th2 Regulatory Cells in both mice and humans.

Highly reactive Cop 1-specific T-Cell lines that secrete IL-4, IL-5, IL-6, IL-10, and Transforming Growth Factor-ß in response to Cop 1 and crossreact with Myelin Basic Protein (MBP) at the level of Th2 Cytokine secretion were established from both Brains and Spinal Cords of Cop 1-treated mice.

In contrast, no reactivity to the control Antigen Lysozyme could be obtained in Lymphocytes isolated from CNS of mice injected with Lysozyme.

Adoptively transferred labeled Cop 1-specific Suppressor Cells were found in Brain sections 7 and 10 days after their injection to the periphery, whereas Lysozyme-specific cells were absent in the CNS.

Hence, Cop 1-induced Th2 cells cross the Blood-Brain Barrier and accumulate in the CNS, where they can be stimulated in situ by MBP and thereby exert therapeutic effects in the diseased organ.

This therapeutic effect was manifested, in Brains of Experimental AutoImmune EncephaloMyelitis-induced mice, by a decrease in the inflammatory Cytokine Interferon- and by secretion of the anti-inflammatory Cytokine IL-10 in response to the AutoAntigen MBP.

In a randomized, placebo-controlled, double-blind study, Glatiramer Acetate (Copaxone) reduced the relapse rate and slowed accumulation of Disability for patients with Relapsing/Remitting Multiple Sclerosis.

Of the original 251 patients randomized to receive Glatiramer Acetate or placebo, 208 chose to continue in an open-label study with all patients receiving active drug.

The majority of the original double-blind cohort continues to receive Glatiramer Acetate by daily subcutaneous injection and are evaluated at 6-month intervals and during suspected relapse.

The data reported here are from approximately 6 years of organized evaluation, including the double-blind phase of up to 35 months and the open-label phase of over 36 months. Daily subcutaneous injections of 20 mg Glatiramer Acetate were well tolerated.

The mean annual relapse rate of the patients who received Glatiramer Acetate since randomization and continued into the open-label study was 0.42 (95% confidence interval (CI), CI=0.34 - 0.51). The rate per year has continued to drop and for the sixth year is 0.23.

Of the group who have received Glatiramer Acetate without interruption for 5 or more years, 69.3% were Neurologically unchanged or have improved from baseline by at least one step on the Expanded Disability Status Scale (EDSS).

Patients who left the open-label phase were surveyed by questionnaire. The majority responded, providing information about their current status and reasons for dropping out.

This study demonstrates the sustained efficacy of Glatiramer Acetate in reducing the relapse rate and in slowing the accumulation of disability in patients with Relapsing forms of Multiple Sclerosis.

We analyzed the effects of Glatiramer Acetate (GA) therapy on in vitro proliferative responses and Cytokine production by Lymphocytes derived from Multiple Sclerosis patients receiving this therapy.

We confirmed that Lymphocytes derived from GA naive patients show a high frequency of response when initially exposed to GA in vitro; this frequency decreased following GA therapy.

The frequency of Lymphocytes responding to whole MBP stimulation did not change with GA therapy.

GA- and MBP-specific T-Cell lines generated from these patients by repeated cycles of in vitro stimulation did not cross react. Some (23%) whole MBP-reactive T-Cell lines did cross react with MBP peptide 83-99.

The mean levels of Interferon-gamma (IFN-γ) secretion and the mean ratio of IFN-γ/IL-5 were lower for GA-reactive cell lines, derived from patients both prior to and during GA therapy, compared to MBP-reactive T-Cell lines.

The proportion of IFN-γ cells in unfractionated Lymphocyte preparations derived from the GA-treated patients did not differ from that found for healthy controls.

Our findings indicate that GA-reactive T-Cell lines derived from GA-treated MS patients continue to show a relative Th2 Cytokine bias consistent with a bystander suppressor function.

GA treatment is not associated with a Cytokine phenotype shift in the total T-Cell or MBP-reactive T-Cell populations.

We recently reported that the post traumatic spread of degeneration in the damaged Optic Nerve can be attenuated by the adoptive transfer of AutoImmune T-Cells specific to Myelin Basic Protein.

However, it would be desirable to obtain Immune NeuroProtection free of any possible AutoImmune Disease.

In an attempt to obtain disease-free Immune NeuroProtection, we used the synthetic four-Amino Acid polymer Copolymer-1 (Cop-1), which is known not to be EnCephalitoGenic despite its cross-reactivity with Myelin Basic Protein.

We show here that active immunization with Cop-1 administered in adjuvant, as well as adoptive transfer of T-Cells reactive to Cop-1, can inhibit the progression of secondary degeneration after crush injury of the rat Optic Nerve.

These results have implications for the treatment of Optic Neuropathies.

Two prior double-blind, placebo-controlled, randomized trials demonstrated that Glatiramer Acetate (GA) reduces relapse rates in patients with Relapsing/Remitting Multiple Sclerosis (RRMS).

This study was designed to determine the effect, onset, and durability of any effect of GA on disease activity monitored with Magnetic Resonance Imaging (MRI) in patients with RRMS.

Two hundred thirty-nine eligible patients were randomized to receive either 20 mg GA (n = 119) or placebo (n = 120) by daily subcutaneous injection.

Eligibility required one or more relapses in the 2 years before entry and at least one enhancing lesion on a screening MRI.

The study was a randomized, double-blind, placebo-controlled phase during which all patients studied underwent monthly MRI scans and clinical assessments over 9 months. The primary outcome measure was the total number of enhancing lesions on T₁-weighted images.

Secondary outcome measures included the proportion of patients with enhancing lesions, the number of new enhancing lesions and change in their volume; the number of new lesions detected on T₂-weighted images and change in their volume, and the change in volume of HypoIntense Lesions seen on unenhanced T₁-weighted images.

Clinical measures of disease activity were also evaluated. The active treatment and placebo groups were comparable at entry for all demographic, clinical, and MRI variables.

Treatment with GA showed a significant reduction in the total number of enhancing Lesions compared with placebo (-10.8, 95% confidence interval -18.0 to -3.7; p = 0.003).

Consistent differences favoring treatment with GA were seen for almost all secondary end points examined:

1. Number of new enhancing lesions (p < 0.003)
2. Monthly change in the volume of enhancing lesions (p = 0.01)
3. Change in volume (p = 0.006)
4. Number of new lesions seen on T₂-weighted images (p < 0.003)

The relapse rate was also significantly reduced by 33% for GA-treated patients (p = 0.012). All effects increased over time. Glatiramer Acetate significantly reduced MRI-measured disease activity and burden.

Copolymer-1 (Copaxone or COP) inhibits Experimental Allergic EncephaloMyelitis and has beneficial effects in Multiple Sclerosis. There is presently no practical in vitro assay for monitoring the Immunological effects of COP.

We used an automated, computer-assisted enzyme-linked ImmunoAdsorbent spot assay for detecting COP-induced Interferon-gamma (IFN-γ) and InterLeukin-4 (IL-4) producing cells.

And a standard proliferation assay to assess the Immunological response to COP in Peripheral Blood MonoNuclear Cells from 20 healthy donors, 20 untreated Multiple Sclerosis patients and 20 COP-treated Multiple Sclerosis patients. Compared with untreated and healthy controls,

COP-treated patients showed:
1. A significant reduction of COP-induced proliferation
2. A positive IL-4 Elispot response
   - mediated predominantly by CD4⁺ Cells, after stimulation with a wide range of COP concentrations
3. An elevated IFN-γ response
   - partially mediated by CD8⁺ Cells, after stimulation with high COP concentrations

All three effects were COP-specific as they were not observed with the control Antigens, Tuberculin-purified protein or Tetanus Toxoid.

Glatiramer Acetate is an approved drug for the treatment of Multiple Sclerosis (MS).

RANTES is a beta-family Chemokine that manifests ChemoAttractant activity for T-Lymphocytes and Monocytes/Macrophages implicated in the PathoGenesis of MS Lesions.

However, the effect of Glatiramer Acetate on the regulation of RANTES secretion in Glial Cells is unknown.

In the present study, we demonstrate for the first time that treatment of human U-251 MG Astrocytic Cells with Glatiramer Acetate blocks Tumor Necrosis Factor-alpha (TNF-)-induced RANTES mRNA and protein in a dose- and time-dependent manner.

This effect is attributed to inhibition of transcription and a 40% decrease in transcript stability.

Furthermore, our electrophoretic mobility shift assays of nuclear extracts from TNF-alpha-treated cells, reveal an increase in DNA-binding activity specific for the nuclear factor-kappa B (NF-kappaB) binding site, in the 5'-flanking promoter region of the human RANTES Gene.

And, that this increase in NF-kappaB binding activity is prevented by pretreatment with Glatiramer Acetate or the NF-kappaB inhibitors.

These findings suggest that Glatiramer Acetate may exert its therapeutic effect in MS partially through inhibiting NF-kappaB activation and Chemokine production.

Free radicals including Peroxynitrite are induced in Multiple Sclerosis (MS). Antioxidant and Peroxynitrite inhibitor Uric Acid (UA), suppresses the MS animal model Experimental AutoImmune Encephalomyelitis (EAE).

MS patients have lower average serum UA than controls. An inverse relationship exists between MS and Gout, Glatiramer Acetate (GA) suppresses EAE and is beneficial in Relapsing MS.

We investigated Serum UA changes during open-label treatment of Relapsing MS with GA. Ten patients (six females, four males, aged 19 to 39 years, mean age 32 years) completed 6 months of GAA (Copaxone 20 mg s.c daily).

Of these, nine completed 12 months. After 6 months on GA, serum UA (normal, 173359 micromol/ml for women, 258-491 micromol/ml for men) increased in nine and marginally decreased (302 to 300 micromol/ml) in a single patient.

Mean UA significantly increased from 240 to 303 micromol/ml (P=0.0014). At 12 months, UA remained significantly higher than at start (P=0.006) decreasing in only one patient.

In contrast, we found no significant UA changes after 6 and 12 months of treatment in 21 MS patients treated with Interferon-ß-1a (Avonex), or in 11 treated with Interferon-ß-1a (Rebif), or in five placebo-treated controls.

Increasing UA, a natural inhibitor of free radicals, may represent a mechanism of action of Glatiramer Acetate in MS.

Background
Copolymer-1 (Cop-1) is a random synthetic Amino Acid copolymer, effective in the treatment of the Relapsing/Remitting form of MS (RRMS).

In vitro and in vivo studies suggest that the mechanism of Cop-1 involves its binding to Major Histocompatibility Complex Class II molecules as an initial step.

Objective
To assess a possible relationship between Human Leukocyte Antigen (HLA) Alleles and response to Cop-1 therapy.

Methods
Eighty-three patients with RRMS, 44 treated with Cop-1 and 39 with Interferon-beta-1a (IFN-beta-1a) for 2 years, were typed by molecular methods for HLA Class II Genes and subgrouped according to clinical outcome.

Results
Data have shown a possible positive correlation between presence of DRB1*1501 and response to Cop-1 therapy (p = 0.008). No relationship between HLA Alleles and therapy has been found in IFN-beta-1a treated patients.

Conclusions
Results suggest that DRB1*1501 might be relevant for the clinical outcome in Cop-1 treated patients and, if confirmed in larger studies, it could be helpful in the selection of RRMS patients for different therapeutic options.

Using a murine model of DeMyelinating disease, we demonstrate that ReMyelination of Spinal Cord Axons is promoted by AntiBodies to Glatiramer Acetate (GA, Copolymer-1, Copaxone), a therapeutic agent for Multiple Sclerosis (MS).

Glatiramer Acetate is a mixture of randomly synthesized Peptides that induces both T-Cell activation and AntiBody production in all treated individuals.

These observations prompted us to compare the independent effects of adoptively transferred GA-reactive T-Cells and AntiBodies in mice with chronic inflammatory DeMyelination induced by Theiler's Virus.

Transferred T-Cells had no effect on lesion load or the extent of ReMyelination. Purified polyclonal GA AntiBodies also did not alter lesion load, which suggests that neither GA T-Cells or AntiBodies were pathogenic.

On the contrary, GA AntiBodies enhanced the normally low level of ReMyelination in chronic lesions.

The AntiBodies, which were primarily ImmunoGlobulin (Ig) G1 and IgG2, cross-reacted with Oligodendrocytes, PeriVascular infiltrating cells, Astrocytes, and Neurons in Spinal Cord sections.

In Glial cultures they bound subsets of early lineage Oligodendrocytes and Microglia. Thus, several mechanisms may have contributed to the promotion of ReMyelination.

These results support the hypothesis that the AntiBody response in GA-treated patients is beneficial by facilitating repair of DeMyelinated lesions.