Moderators of Improvements in Fatigue Impact After a Self-management Intervention in Multiple Sclerosis: A Secondary Analysis of a Randomized Controlled Trial

ABSTRACT

Fatigue is one of the most common and disabling symptoms of multiple sclerosis. A recent randomized controlled trial comparing a fatigue self-management program and a general multiple sclerosis education program found that both programs improved fatigue in participants with multiple sclerosis. Participants were randomized to a self-management program (fatigue: take control, n = 109) or a multiple sclerosis education program (multiple sclerosis: take control, n = 109). This secondary analysis of that trial used multilevel moderation analysis to examine moderators of treatment-related effects on fatigue (Modified Fatigue Impact Scale) from baseline through the 6-mo follow-up. The following potential treatment moderators were examined: age, sex, cohabitation/marital status, and baseline levels of self-efficacy, depression symptoms, and sleep quality. Cohabitation status (living with or without a spouse/partner) interacted with intervention group and time to predict fatigue impact (P = 0.04). Fatigue: take control participants who lived with a spouse/partner showed a marginal effect in greater rate of improvement in fatigue compared with those who lived alone (P = 0.08). However, rates of improvement in fatigue in multiple sclerosis: take control participants were similar in those living with or without a spouse/partner. These findings suggest that living with a spouse or partner may facilitate benefit from self-management interventions for multiple sclerosis-related fatigue. Future research should investigate the contribution of supportive others in self-management of fatigue in multiple sclerosis.

Characteristics of Prescription Drug Use Among Individuals With Multiple Sclerosis in the US Medicare Population

BACKGROUND

Few studies have characterized the full spectrum of prescription drug use for individuals with multiple sclerosis (MS). The objective of this study was to describe patterns and expenditures for disease-modifying therapies (DMTs) and other prescription drugs among Medicare beneficiaries with MS.

METHODS

Using Medicare claims data in 2014, we identified a cohort of Medicare beneficiaries with 12 months of continuous eligibility and 3 or more MS-related inpatient, outpatient, or prescription claims. We quantified the number, type, and costs of prescribed DMTs and other medications for MS-related symptoms. Medication costs were calculated according to whether beneficiaries received additional subsidies, which eliminate most out-of-pocket costs.

RESULTS

Of 43,283 Medicare beneficiaries identified with MS, 70% were DMT users. Most used self-administered DMTs (67%), and 3% used natalizumab; 93% received a supportive care medication. Among the 82% of individuals without subsidies, the annual median total and out-of-pocket DMT costs were $56,794 (interquartile range [IQR], $44,837-$62,038) and $4566 (IQR, $849-$5270), respectively. The most commonly used supportive care drugs were antidepressants (62%), opioid analgesics (50%), antispasticity drugs (47%), and anticonvulsants (46%). Annual median total and out-of-pocket costs for these drugs were $15,134 (IQR, $6571-$19,620) and $255 (IQR, $56-$877), respectively.

CONCLUSIONS

Most Medicare beneficiaries with MS using DMTs face considerable out-of-pocket costs. Beneficiaries also used a significant number of medications potentially used for MS-related symptoms, although total and out-of-pocket costs were modest.

Characterization of the Clinical Evidence Supporting Repository Corticotropin Injection for FDA-Approved Indications: A Scoping Review

IMPORTANCE

Repository corticotropin injection is an expensive medication that was approved in 1952 for the treatment of many inflammatory conditions. The clinical evidence supporting the use of repository corticotropin (hereinafter referred to as corticotropin) has been weak, perhaps because its approval predated the modern review standards of the US Food and Drug Administration (FDA).

OBJECTIVE

To characterize the clinical evidence supporting the use of corticotropin for its FDA-approved indications.

EVIDENCE REVIEW

Studies were identified via electronic searches of Ovid MEDLINE, the Cumulative Index of Nursing and Allied Health Literature (CINAHL), and the Cochrane Central Register of Controlled Trials (CENTRAL) from database inception to May 12, 2021 (the MEDLINE search was updated on June 8, 2021). Bibliographies of retrieved articles were also reviewed through ClinicalTrials.gov, FDA documents, and the manufacturer's website. Search terms included HP Acthar, ACTH gel, repository corticotropin, and terms for specific diseases, such as multiple sclerosis, nephrotic syndrome, rheumatoid arthritis, and West syndrome (or spasms, infantile). The review included randomized clinical trials (RCTs), nonrandomized and single-arm clinical trials, and prospective cohort studies that compared corticotropin with an active comparator, placebo, or no treatment. Data were extracted by 1 reviewer and verified by a second. Disagreements were resolved through discussion. Studies were qualitatively synthesized by indication to summarize important design features and results.

FINDINGS

Of 1059 records screened, 203 full-text articles were assessed for eligibility. A total of 41 studies involving 2235 participants met inclusion criteria; of those, 11 involved infantile spasms, 10 involved multiple sclerosis (MS), 11 involved rheumatological conditions, 7 involved nephrotic syndrome, 1 involved ocular conditions, and 1 involved sarcoidosis. Overall, 19 studies either included a single arm or exclusively compared different corticotropin dosing strategies. The evidence was most robust for the treatment of infantile spasms and MS. The largest number of studies comparing corticotropin with an active agent (n = 4) or placebo (n = 5) pertained to MS, with almost all studies finding that corticotropin performed better than placebo but no different than corticosteroids. For the treatment of infantile spasms, 8 controlled studies were identified (6 were randomized); of those, only 1 small RCT found corticotropin to be significantly superior to corticosteroids. Studies of patients with other conditions (n = 20) frequently lacked a control group (n = 12), were placebo-controlled (n = 5), or exclusively examined different corticotropin dosing strategies (n = 2). Placebo-controlled RCTs of rheumatoid arthritis, ankylosing spondylitis, optic neuritis, systemic lupus erythematosus, and nephrotic syndrome were generally small and did not consistently demonstrate that corticotropin was superior to placebo. Blinded RCTs showed a similar or greater number of adverse effects with corticotropin relative to corticosteroids.

CONCLUSIONS AND RELEVANCE

In this scoping review, few RCTs supported the clinical benefit of corticotropin for most FDA-approved indications. Most RCTs found that corticotropin was not superior to corticosteroids for treating relapses of MS or infantile spasms.

Association Between Pharmacy Benefit Restrictions and Disease-Modifying Therapy Use in the Medicare Part D Program

Background and Objectives

To determine the association between Medicare Part D plan disease-modifying therapy (DMT) restrictiveness and adherence and outcomes among people with multiple sclerosis (MS).

Methods

We used Medicare claims data from 2010 to 2014 to identify individuals with a full year enrollment (Parts A, B, and D), an MS diagnosis, and 1 or more self-administered DMT prescription. Plans were considered restrictive if all available DMTs required a prior authorization or step therapy restriction; otherwise they were considered permissive. We compared DMT adherence, defined as a medication possession ratio ≥80%, MS-related emergency department or inpatient admissions, and outpatient visits by Part D plan restrictiveness. We used multivariate regression models to control for patient demographics and comorbidities.

Results

There were 37,713 Medicare beneficiaries with MS who were enrolled in either restrictive (n = 29,901) or permissive (n = 7812) Part D plans during the study period. Patients enrolled in restrictive plans were older (60 vs 58 years; p < 0.001), more likely to live in the south (38% vs 23%; p < 0.001), eligible through disability (67% vs 60%; p < 0.001), and more likely to have several chronic comorbid conditions. Patients enrolled in restrictive plans were less likely to be adherent to their DMT (54% vs 57%; p < 0.001; adjusted odds ratio [aOR] 0.92, 95% confidence interval [CI] 0.88-0.98) and had a higher rate of MS-related outpatient visits (1.7 vs 1.4 per year; p < 0.001; aRR 1.27, 95% CI 1.23-1.31).

Discussion

Medicare beneficiaries with MS enrolled in restrictive Part D plans were less adherent to their DMT and had higher rates of MS-related outpatient visits.

Gray matter blood-brain barrier water exchange dynamics are reduced in progressive multiple sclerosis

Background and Purpose

To compare transcapillary wall water exchange, a putative marker of cerebral metabolic health, in brain T₂ white matter (WM) lesions and normal appearing white and gray matter (NAWM and NAGM, respectively) in individuals with progressive multiple sclerosis (PMS) and healthy controls (HC).

Methods

Dynamic‐contrast‐enhanced 7T MRI data were obtained from 19 HC and 23 PMS participants. High‐resolution pharmacokinetic parametric maps representing tissue microvascular and microstructural properties were created by shutter‐speed (SS) paradigm modeling to obtain estimates of blood volume fraction (v_b), water molecule capillary efflux rate constant (k_po), and the water capillary wall permeability surface area product (P_wS ≡ v_b*k_po). Linear regression models were used to investigate differences in (i) k_po and P_wS between groups in NAWM and NAGM, and (ii) between WM lesions and NAWM in PMS.

Results

High‐resolution parametric maps were produced to visualize tissue classes and resolve individual WM lesions. Normal‐appearing gray matter k_po and P_wS were significantly decreased in PMS compared to HC (p ≤ .01). Twenty‐one T₂ WM lesions were analyzed in 10 participants with PMS. k_po was significantly decreased in WM lesions compared to PMS NAWM (p < .0001).

Conclusions

Transcapillary water exchange is reduced in PMS NAGM compared to HC and is further reduced in PMS WM lesions, suggesting pathologically impaired brain metabolism. k_po provides a sensitive measure of cerebral metabolic activity and/or coupling, and can be mapped at higher spatial resolution than conventional imaging techniques assessing metabolic activity.

MRI characteristics of Japanese macaque encephalomyelitis: Comparison to human diseases

BACKGROUND AND PURPOSE

To describe MRI findings in Japanese macaque encephalomyelitis (JME) with emphasis on lesion characteristics, lesion evolution, normal-appearing brain tissue, and similarities to human demyelinating disease.

METHODS

MRI data were obtained from 114 Japanese macaques, 30 presenting neurological signs of JME. All animals were screened for presence of T2 -weighted white matter signal hyperintensities; animals with behavioral signs of JME were additionally screened for contrast-enhancing lesions. Whole-brain quantitative T1 maps were collected, and histogram analysis was performed with regression across age to evaluate microstructural changes in normal appearing brain tissue in JME and neurologically normal animals. Quantitative estimates of blood-brain-barrier (BBB) permeability to gadolinium-based-contrast agent (GBCA) were obtained in acute, GBCA-enhancing lesions. Longitudinal imaging data were acquired for 15 JME animals.

RESULTS

One hundred and seventy-three focal GBCA-enhancing lesions were identified in 30 animals demonstrating behavioral signs of neurological dysfunction. JME GBCA-enhancing lesions were typically focal and ovoid, demonstrating highest BBB GBCA permeability in the lesion core, similar to acute, focal multiple sclerosis lesions. New GBCA-enhancing lesions arose rapidly from normal-appearing tissue, and BBB permeability remained elevated for weeks. T1 values in normal-appearing tissue were significantly associated with age, but not with sex or disease.

CONCLUSIONS

Intense, focal neuroinflammation is a key MRI finding in JME. Several features of JME compare directly to human inflammatory demyelinating diseases. Investigation of JME combined with the development and validation of noninvasive imaging biomarkers offers substantial potential to improve diagnostic specificity and contribute to the understanding of human demyelinating diseases.

Myelin-specific T cells in animals with Japanese macaque encephalomyelitis

Objective

To determine whether animals with Japanese macaque encephalomyelitis (JME), a spontaneous demyelinating disease similar to multiple sclerosis (MS), harbor myelin‐specific T cells in their central nervous system (CNS) and periphery.

Methods

Mononuclear cells (MNCs) from CNS lesions, cervical lymph nodes (LNs) and peripheral blood of Japanese macaques (JMs) with JME, and cervical LN and blood MNCs from healthy controls or animals with non‐JME conditions were analyzed for the presence of myelin‐specific T cells and changes in interleukin 17 (IL‐17) and interferon gamma (IFNγ) expression.

Results

Demyelinating JME lesions contained CD4⁺ T cells and CD8⁺ T cells specific to myelin oligodendrocyte glycoprotein (MOG), myelin basic protein (MBP), and/or proteolipid protein (PLP). CD8⁺ T‐cell responses were absent in JME peripheral blood, and in age‐ and sex‐matched controls. However, CD4⁺ Th1 and Th17 responses were detected in JME peripheral blood versus controls. Cervical LN MNCs from eight of nine JME animals had CD3⁺ T cells specific for MOG, MBP, and PLP that were not detected in controls. Mapping myelin epitopes revealed a heterogeneity in responses among JME animals. Comparison of myelin antigen sequences with those of JM rhadinovirus (JMRV), which is found in JME lesions, identified six viral open reading frames (ORFs) with similarities to myelin antigen sequences. Overlapping peptides to these JMRV ORFs did not induce IFNγ responses.

Interpretations

JME possesses an immune‐mediated component that involves both CD4⁺ and CD8⁺ T cells specific for myelin antigens. JME may shed new light on inflammatory demyelinating disease pathogenesis linked to gamma‐herpesvirus infection.

Thyroid hormone and thyromimetics inhibit myelin and axonal degeneration and oligodendrocyte loss in EAE

We have previously demonstrated that thyromimetics stimulate oligodendrocyte precursor cell differentiation and promote remyelination in murine demyelination models. We investigated whether a thyroid receptor-beta selective thyromimetic, sobetirome (Sob), and its CNS-targeted prodrug, Sob-AM2, could prevent myelin and axonal degeneration in experimental autoimmune encephalomyelitis (EAE). Compared to controls, EAE mice receiving triiodothyronine (T3, 0.4 mg/kg), Sob (5 mg/kg) or Sob-AM2 (5 mg/kg) had reduced clinical disease and, within the spinal cord, less tissue damage, more normally myelinated axons, fewer degenerating axons and more oligodendrocytes. T3 and Sob also protected cultured oligodendrocytes against cell death. Thyromimetics thus might protect against oligodendrocyte death, demyelination and axonal degeneration as well as stimulate remyelination in multiple sclerosis.

Trends In Coverage For Disease-Modifying Therapies For Multiple Sclerosis In Medicare Part D

The high cost of multiple sclerosis (MS) disease-modifying therapies can negatively affect access for patients through increased payer restrictions and higher out-of-pocket spending. Our objective was to describe changes in pharmacy benefit coverage and cost-sharing amounts for MS disease-modifying therapies in the Medicare Part D program, using enrollment-weighted Prescription Drug Plan Formulary files for the period 2007-16. Among therapies available throughout the study period, the rate of prior authorization use increased from 61-66 percent of plans to 84-90 percent. The share of plans with at least one therapy available without limitations declined from 39 percent to 17 percent. The projected cumulative out-of-pocket spending for 2019 was $6,894. The therapy with the highest out-of-pocket spending was generic glatiramer acetate. Policy makers need to consider both access restrictions and a growing cost-sharing burden as potential consequences of high and rising drug prices for people with MS.

Observation of Reduced Homeostatic Metabolic Activity and/or Coupling in White Matter Aging

BACKGROUND AND PURPOSE

Transvascular water exchange plays a key role in the functional integrity of the blood-brain barrier (BBB). In white matter (WM), a variety of imaging modalities have demonstrated age-related changes in structure and metabolism, but the extent to which water exchange is altered remains unclear. Here, we investigated the cumulative effects of healthy aging on WM capillary water exchange.

METHODS

A total of 38 healthy adults (aged 36-80 years) were studied using 7T dynamic contrast enhanced MRI. Blood volume fraction (v_b ) and capillary water efflux rate constant (k_po ) were determined by fitting changes in the ¹ H₂ O longitudinal relaxation rate constant (R₁ ) during contrast agent bolus passage to a two-compartment exchange model. WM volume was determined by morphometric analysis of structural images.

RESULTS

R₁ values and WM volume showed similar trajectories of age-related decline. Among all subjects, v_b and k_po averaged 1.7 (±0.5) mL/100 g of tissue and 2.1 (±1.1) s^-1 , respectively. While v_b showed minimal changes over the 40-year-age span of participants, k_po declined 0.06 s^-1 (ca. 3%) per year (r = -.66; P < .0005), from near 4 s^-1 at age 30 to ca. 2 s^-1 at age 70. The association remained significant after controlling for WM volume.

CONCLUSIONS

Previous studies have shown that k_po tracks Na⁺ , K⁺ -ATPase activity-dependent water exchange at the BBB and likely reflects neurogliovascular unit (NGVU) coupled metabolic activity. The age-related decline in k_po observed here is consistent with compromised NGVU metabolism in older individuals and the dysregulated cellular bioenergetics that accompany normal brain aging.

Closing the Part D Coverage Gap and Out-of-Pocket Costs for Multiple Sclerosis Drugs

Objective

To determine whether closing the Part D coverage gap (donut hole) between 2010 and 2019 lowered patients' out-of-pocket costs for disease-modifying therapies (DMTs) for multiple sclerosis (MS).

Methods

Using nationwide Medicare Formulary and Drug Pricing Files, we analyzed Part D drug benefit design and DMT prices in 2010, 2016, and 2019. We calculated average monthly list prices for DMTs available in each year (4 DMTs in 2010, 11 DMTs in 2016, and 14 DMTs in 2019). We projected patients' annual out-of-pocket cost for each DMT alone under a standard Part D plan in that year. We estimated potential savings attributable to closing the coverage gap between 2010 and 2019 (beneficiaries' cost sharing dropped from 100% to 25%) under 3 scenarios: no increase in price, an inflation-indexed price increase (3% annually), and the observed price increase.

Results

Median monthly DMT prices rose from $2,804 to $5,987 to $7,009 over the years 2010, 2016, and 2019, respectively. Median projected annual out-of-pocket costs rose from $5,916 to $6,229 to $6,618. With unchanged or inflation-indexed DMT price changes, closing the coverage gap would have reduced annual out-of-pocket costs by $2,260 (38% reduction) and $1,744 (29% reduction), respectively. Despite having the lowest monthly price, generic glatiramer acetate had among the highest out-of-pocket costs ($6,731 to $6,939 a year) in 2019.

Conclusions

Medicare Part D beneficiaries can pay thousands of dollars yearly out of pocket for DMTs. Closing the Part D coverage gap did not reduce out-of-pocket costs for patients because of simultaneous increases in DMT prices.

Effect of generic glatiramer acetate on spending and use of drugs for multiple sclerosis

Objective

To estimate changes in costs and utilization trends for disease-modifying therapies (DMTs) from 2011 to 2017 in the US Medicaid program.

Methods

Using quarterly Medicaid State Drug Utilization Data from 2011 to 2017, we summarize trends in spending, utilization, and costs per prescription for 15 multiple sclerosis (MS) DMTs including brand and generic versions of glatiramer acetate. We use interrupted time series regression to estimate the effect of market entry of generic glatiramer acetate on cost per prescription of other self-administered DMTs.

Results

Gross annual expenditures on MS DMTs increased from $453 million to $1.32 billion between 2011 and 2017 within the Medicaid program. Increased spending was primarily driven by increases in per prescription costs, which doubled during the study period. Although total utilization was stable, product specific utilization shifted from injectable to oral DMTs. However, throughout the study, the plurality of utilization was glatiramer acetate. The introduction of generic glatiramer acetate in Q2 of 2015 was associated with an immediate increase of $441 (95% confidence interval [CI] $184–$697; p < 0.001) in the cost per prescription of branded glatiramer acetate followed by a gradual $52 per prescription reduction (95% CI −$86 to −$18) over time. There were minimal changes in the costs for the other DMTs.

Conclusions

Spending on MS DMTs in the Medicaid program have more than doubled over the last 7 years primarily as a function of higher costs per prescription. Introduction of a generic glatiramer acetate product in 2015 had nominal effects on overall price trajectories and utilization within the class.

Qualitative study on the price of drugs for multiple sclerosis

Objective

To describe pricing decisions, justifications, and attitudes among current and former biotech industry executives for companies that manufacture multiple sclerosis disease-modifying therapies.

Methods

Four leaders in biotech who have been directly involved in multiple sclerosis disease-modifying therapy pricing or marketing volunteered to participate in 30-minute semistructured interviews conducted via telephone. An expert in qualitative methods moderated and analyzed the interviews alongside the principal investigator. Brief, preinterview online surveys were also administered to provide additional context and insight for discussion. Interviews were audio-recorded and professionally transcribed.

Results

Participants consistently stated that initial price decisions were dictated by the price of existing competitors in the market. Revenue maximization and corporate growth were drivers of price escalations in the absence of continued market penetration. Lower revenue predictions outside the United States also informed pricing strategies. The growing complexity and clout of drug distribution and supply channels were also cited as contributing factors. Although decisions to raise prices were motivated by the need to attract investment for future innovation, recouping drug-specific research and development costs as a justification was not strongly endorsed as having a significant influence on pricing decisions.

Conclusions

Contrary to prevailing narratives that underscore drug development costs, findings from our interviews suggest that the existing price ecosystem, overall corporate growth, international pricing disparities, and supply chain–related distortions may play a more central role in drug pricing decision.

Effect of High-Intensity Exercise on Multiple Sclerosis Function and Phosphorous Magnetic Resonance Spectroscopy Outcomes

PURPOSE

We determined if a high-intensity aerobic exercise program would be safe, improve expected fitness and clinical outcomes, and alter exploratory phosphorous magnetic resonance spectroscopy (P MRS) outcomes in persons with multiple sclerosis (PwMS).

METHODS

This open-label prospective pilot study compared two cohorts of ambulatory PwMS matched for age, sex and V˙O2max. Cohorts underwent 8 wk of high-intensity aerobic exercise (MS-Ex, n = 10) or guided stretching (MS-Ctr, n = 7). Aerobic exercise consisted of four 30-min sessions per week while maintaining ≥70% maximal HR. Changes in cardiorespiratory fitness, clinical outcomes, and P MRS of tibialis anterior (TA) muscle and brain were compared. Cross-sectional P MRS comparisons were made between all MS participants and a separate matched healthy control population.

RESULTS

The MS-Ex cohort achieved target increases in V˙O2max (mean, +12.7%; P = <0.001, between-group improvement, P = 0.03). One participant was withdrawn for exercise-induced syncope. The MS-Ex cohort had within-group improvements in fat mass (-5.8%; P = 0.04), lean muscle mass (+2.6%; P = 0.02), Symbol Digit Modalities Test (+15.1%; P = 0.04), and cognitive subscore of the Modified Fatigue Impact Scale (-26%; P = 0.03), whereas only the physical subscore of the Modified Fatigue Impact Scale improved in MS-Ctr (-16.1%; P = 0.007). P MRS revealed significant within-group increases in MS-Ex participants in TA rate constant of phosphocreatine (PCr) recovery (+31.5%; P = 0.03) and adenosine triphosphate/PCr (+3.2%; P = 0.01), and near significant between-group increases in TA PCr recovery rate constant (P = 0.05) but no significant changes in brain P MRS after exercise. Cross-sectional differences existed between MS and healthy control brain PCr/inorganic phosphate (4.61 ± 0.44, 3.93 ± 0.19; P = 0.0019).

CONCLUSIONS

High-intensity aerobic exercise in PwMS improved expected cardiorespiratory and clinical outcomes but provoked one serious adverse event. The P MRS may serve to explore underlying mechanisms by which aerobic exercise exerts cerebral benefits.

Oral lipoic acid as a treatment for acute optic neuritis: a blinded, placebo controlled randomized trial

Background

Lipoic acid, an antioxidant, has beneficial effects in experimental acute optic neuritis and autoimmune encephalomyelitis. Optical coherence tomography can detect retinal nerve fiber layer thinning, representing axonal degeneration, approximately 3–6 months after acute optic neuritis.

Objective

To determine whether lipoic acid is neuroprotective in acute optic neuritis.

Methods

A single-center, double-blind, randomized, placebo controlled, 24-week trial. Intervention included 6 weeks of once daily lipoic acid (1200 mg) or placebo within 14 days of acute optic neuritis diagnosis. The primary outcome was the mean difference in affected eye retinal nerve fiber layer (RNFL) thickness from baseline to 24 weeks.

Results

We enrolled 31 subjects (placebo n=16; lipoic acid n=15; average age 38.6 years (standard deviation (SD) 10.3)). Affected eye mean global RNFL thickness (µm) in the lipoic acid group decreased from 108.47 (SD 26.11) at baseline to 79.31 (SD 19.26) at 24 weeks. The affected eye RNFL in the placebo group decreased from 103.67 (SD 18.04) at baseline to 84.43 (SD 20.94) at 24 weeks. Unaffected eye RNFL thickness did not significantly change in either group over 24 weeks.

Conclusion

Six weeks of oral lipoic acid supplementation after acute optic neuritis is safe and well tolerated; however, because of insufficient recruitment, we could not conclude that lipoic acid treatment was neuroprotective in acute optic neuritis.

Repository Corticotropin Versus Glucocorticoid for Nephrotic Syndrome: When Will We See the Evidence?

Despite little evidence supporting its superiority to glucocorticoid therapy, use and expenditures for repository corticotropin (rACTH) injection (H.P. Acthar Gel; Mallinckrodt) have increased dramatically in the last 5 years, particularly among a small number of nephrologists, rheumatologists, and neurologists. Recently, the manufacturer justified the extremely high and rapidly increasing cost of rACTH by citing the ongoing need to generate clinical data to support its use. We test this assertion by investigating the quality and provenance of the evidence likely to emerge in the foreseeable future. We identified all completed, in-progress, and proposed studies of rACTH registered at ClinicalTrials.gov. 75 studies representing 2,953 participants met inclusion criteria. Studies addressed primarily nephrologic (n = 23), rheumatologic (n = 28), and neurologic (n =22) indications. Of the 23 studies proposed for renal indications (enrollment, 33 ± 49 [mean ± SD]), 11 were not randomized, 8 compared only different rACTH treatment regimens, and 4 compared rACTH to placebo. No studies of rACTH proposed for renal indications included an rACTH-free arm receiving active treatment (ie, another form of immunosuppression). We conclude that evidence emerging in the foreseeable future is unlikely to broadly support rACTH use over lower-cost glucocorticoid-based alternatives for renal indications.

Longitudinal optical coherence tomography study of optic atrophy in secondary progressive multiple sclerosis: Results from a clinical trial cohort

BACKGROUND

Limited prospective information exists regarding spectral-domain optical coherence tomography (SD-OCT) in secondary progressive multiple sclerosis (SPMS).

OBJECTIVE

Document cross-sectional and longitudinal retinal nerve fiber layer (RNFL) and macular ganglion cell plus inner plexiform layer (GCIPL) features of an SPMS clinical trial cohort.

METHODS

Prospective, observational study using a 2-year randomized placebo-controlled SPMS trial cohort with yearly SD-OCT testing. Post hoc analysis determined influences of optic neuritis (ON), disease duration, and baseline SD-OCT on annualized atrophy rates and on correlations between OCT and brain atrophy.

RESULTS

Mean RNFL and GCIPL values of patients ( n = 47, mean age = 59 years, mean disease duration = 30 years) were significantly lower among eyes with prior ON than those without (no history of ON (NON)). Annualized RNFL (-0.31 µm/year) and GCIPL (-0.29 µm/year) atrophy rates did not differ between ON and NON eyes. Baseline RNFL thickness >75 µm was associated with greater annualized RNFL atrophy (-0.85 µm/year). Neither RNFL nor GCIPL atrophy correlated with whole-brain atrophy.

CONCLUSION

This study suggests that eyes with and without ON history may be pooled for atrophy analysis in SPMS clinical trials using SD-OCT. Low baseline RNFL, small retinal atrophy rates, and lack of correlation with whole-brain atrophy in this population are important trial design considerations.

Effects of lipoic acid on walking performance, gait, and balance in secondary progressive multiple sclerosis

BACKGROUND

Gait and balance impairment is common in secondary progressive multiple sclerosis (SPMS). Lipoic acid (LA), an over-the-counter antioxidant, is effective in MS animal models and may improve walking speed, but effects on mobility are unreported.

OBJECTIVE

Examine the effects of 1200 mg daily oral dose of LA versus placebo (PLA) on gait and balance in a 2-year, randomized, double-blind pilot study.

METHODS

134 participants were screened for eligibility before assignment to LA (n = 28) or PLA (n = 26). Included here were, 21 participants with SPMS who took LA (N = 11) or PLA (N = 10) capsules for 2 years (enrolled May 2, 2011 - August 14, 2015) and completed all tasks without the use of an assistive device. Participants completed the Timed Up and Go (TUG) and quiet standing tasks every 6 months while wearing inertial sensors (APDM Opals) to quantify mobility.

RESULTS

LA had a medium effect on time to complete TUG at 2 years (g = 0.51; 95% CI = -0.35, 1.38). In a subset of 18 participants with less disability (EDSS < 6, no use of ambulatory device), turning time was significantly shorter with LA (p =  0.048, Δ= 0.48 s). No differences in balance metrics were found between groups.

CONCLUSIONS

LA had an effect on walking performance in people with SPMS, particularly in those with lower baseline disability.

TRIAL REGISTRATION

Lipoic Acid for Secondary Progressive Multiple Sclerosis https://clinicaltrials.gov/ct2/show/NCT01188811?term=spain+lipoic+acid&rank=1 NCT0118881.

Industry Payments to Physician Specialists Who Prescribe Repository Corticotropin

Importance

Despite great expense and little evidence supporting use over corticosteroids, prescriptions for repository corticotropin (H. P. Acthar Gel; Mallinckrodt Pharmaceuticals) have increased markedly. Aggressive sales tactics and payments from the manufacturer may influence prescribing behavior for this expensive medication.

Objective

To characterize industry payments to physician specialists who prescribe corticotropin in the Medicare program.

Design, Setting, and Participants

This study was a cross-sectional analysis of Centers for Medicare & Medicaid Services 2015 Part D prescribing data linked to 2015 Open Payments data. Nephrologists, neurologists, and rheumatologists with more than 10 corticotropin prescriptions (frequent prescribers) in 2015 were included.

Exposures

Frequency, category, and magnitude of corticotropin-related payments from Mallinckrodt recorded in the Open Payments database.

Main Outcomes and Measures

Frequency, category, and magnitude of corticotropin-related payments from Mallinckrodt, as well as corticotropin prescriptions and expenditures for Medicare beneficiaries.

Results

Of the 235 included physicians, 65 were nephrologists; 59, neurologists; and 111, rheumatologists. A majority of frequent corticotropin prescribers (207 [88%]) received corticotropin-related payments from Mallinckrodt. The median (range) total payment for 2015 was $189 ($11-$138 321), with the highest payments ranging from $56 549 to $138 321 across the specialties. More than 20% of frequent prescribers received more than $10 000 and the top quartile of recipients received a median (range) of $33 190 ($9934-$138 321) in total payments per prescriber. Payments for compensation for services other than consulting contributed the most to the total amount. Mallinckrodt payments were positively associated with greater Medicare spending on corticotropin (β = 1.079; 95% CI, 1.044-1.115; P < .001), with every $10 000 in payments associated with a 7.9% increase (approximately $53 000) in Medicare spending on corticotropin. There was no association between corticotropin-related payments and spending on prescriptions for synthetic corticosteroids.

Conclusions and Relevance

In this study, most nephrologists, neurologists, and rheumatologists who frequently prescribe corticotropin received corticotropin-related payments from Mallinckrodt. These findings suggest that financial conflicts of interest may be driving use of corticotropin in the Medicare program.

Trends and Characteristics of US Medicare Spending on Repository Corticotropin

This study uses Medicare Drug Spending Dashboard data to estimate the cost of repository corticotropin to the Medicare program and assess its within-specialty prescribing patterns.

The contemporary spectrum of multiple sclerosis misdiagnosis: A multicenter study

OBJECTIVE

To characterize patients misdiagnosed with multiple sclerosis (MS).

METHODS

Neurologists at 4 academic MS centers submitted data on patients determined to have been misdiagnosed with MS.

RESULTS

Of 110 misdiagnosed patients, 51 (46%) were classified as "definite" and 59 (54%) "probable" misdiagnoses according to study definitions. Alternate diagnoses included migraine alone or in combination with other diagnoses 24 (22%), fibromyalgia 16 (15%), nonspecific or nonlocalizing neurologic symptoms with abnormal MRI 13 (12%), conversion or psychogenic disorders 12 (11%), and neuromyelitis optica spectrum disorder 7 (6%). Duration of misdiagnosis was 10 years or longer in 36 (33%) and an earlier opportunity to make a correct diagnosis was identified for 79 patients (72%). Seventy-seven (70%) received disease-modifying therapy and 34 (31%) experienced unnecessary morbidity because of misdiagnosis. Four (4%) participated in a research study of an MS therapy. Leading factors contributing to misdiagnosis were consideration of symptoms atypical for demyelinating disease, lack of corroborative objective evidence of a CNS lesion as satisfying criteria for MS attacks, and overreliance on MRI abnormalities in patients with nonspecific neurologic symptoms.

CONCLUSIONS

Misdiagnosis of MS leads to unnecessary and potentially harmful risks to patients. Misinterpretation and misapplication of MS clinical and radiographic diagnostic criteria are important contemporary contributors to misdiagnosis.

A highly immunogenic trivalent T cell receptor peptide vaccine for multiple sclerosis

Background: T cell receptor (TCR) peptide vaccination is a novel approach to treating multiple sclerosis (MS). The low immunogenicity of previous vaccines has hindered the development of TCR peptide vaccination for MS. Objective: To compare the immunogenicity of intramuscular injections of TCR BV5S2, BV6S5 and BV13S1 CDR2 peptides in incomplete Freund’s adjuvant (IFA) with intradermal injections of the same peptides without IFA. Methods: MS subjects were randomized to receive TCR peptides/IFA, TCR peptides/saline or IFA alone. Subjects were on study for 24 weeks. Results: The TCR peptides/IFA vaccine induced vigorous T cell responses in 100% of subjects completing the 24-week study (9/9) compared with only 20% (2/10) of those receiving the TCR peptides/saline vaccine (P =0.001). IFA alone induced a weak response in only one of five subjects. Aside from injection site reactions, there were no significant adverse events attributable to the treatment. Conclusions: The trivalent TCR peptide in IFA vaccine represents a significant improvement in immunogenicity over previous TCR peptide vaccines and warrants investigation of its ability to treat MS.

Immunopathology of Japanese macaque encephalomyelitis is similar to multiple sclerosis

Japanese macaque encephalomyelitis (JME) is an inflammatory demyelinating disease that occurs spontaneously in a colony of Japanese macaques (JM) at the Oregon National Primate Research Center. Animals with JME display clinical signs resembling multiple sclerosis (MS), and magnetic resonance imaging reveals multiple T2-weighted hyperintensities and gadolinium-enhancing lesions in the central nervous system (CNS). Here we undertook studies to determine if JME possesses features of an immune-mediated disease in the CNS. Comparable to MS, the CNS of animals with JME contain active lesions positive for IL-17, CD4+ T cells with Th1 and Th17 phenotypes, CD8+ T cells, and positive CSF findings.

Practices of US health insurance companies concerning MS therapies interfere with shared decision-making and harm patients

The US Food and Drug Administration has registered 13 multiple sclerosis (MS) disease-modifying therapies (DMTs). The medications are not interchangeable as they vary in route of administration, efficacy, and safety profile. Selecting the appropriate MS DMT for individual patients requires shared decision-making between patients and neurologists. To reduce costs, insurance companies acting through pharmacy benefit companies restrict access to MS DMTs through tiered coverage and other regulations. We discuss how policies established by insurance companies that limit access to MS DMTs interfere with the process of shared decision-making and harm patients. We present potential actions that neurologists can take to change how insurance companies manage MS DMTs.

Fear of Falling Is Associated with Recurrent Falls in People with Multiple Sclerosis: A Longitudinal Cohort Study

BACKGROUND

People with multiple sclerosis (MS) fall frequently, and there are few clinically valid tools to measure the risk factors for falls. We assessed the unidimensionality of the 7-item Falls Efficacy Scale-International (FES-I), a measure of fear of falling, and determined whether the 7-item FES-I is associated with recurrent falls in people with MS.

METHODS

Falls were counted prospectively for 6 months using fall calendars in 58 people with MS (age, 18-50 years; Expanded Disability Status Scale score, 0-6). The FES-I was administered at baseline, and its unidimensionality was assessed by confirmatory factor analysis. The relationship between FES-I score and future falls, after adjusting for recurrent falls in the past year, was assessed by logistic regression.

RESULTS

Fifty-four participants who completed all assessments were included in the analysis. Goodness-of-fit indices confirmed a single-factor solution for the 7-item FES-I (discrepancy χ(2), P = .101; Tucker-Lewis index, 0.953; comparative fit index, 0.969; root mean square error of approximation, 0.098). There was a significant association between fear of falling and falls in the following 3 months, independent of recurrent falls in the past year (odds ratio = 1.22, 95% confidence interval, 1.04-1.43, P = .016).

CONCLUSIONS

The 7-item FES-I demonstrates good construct validity, allowing the total score to be used as a measure of fear of falling in people with MS. Fear of falling, as measured by the 7-item FES-I, is associated with future recurrent falls independent of past recurrent falls in people with MS.

Mapping human brain capillary water lifetime: high-resolution metabolic neuroimaging

Shutter-speed analysis of dynamic-contrast-agent (CA)-enhanced normal, multiple sclerosis (MS), and glioblastoma (GBM) human brain data gives the mean capillary water molecule lifetime (τ(b)) and blood volume fraction (v(b); capillary density-volume product (ρ(†)V)) in a high-resolution (1)H2O MRI voxel (40 μL) or ROI. The equilibrium water extravasation rate constant, k(po) (τ(b)(-1)), averages 3.2 and 2.9 s(-1) in resting-state normal white matter (NWM) and gray matter (NGM), respectively (n = 6). The results (italicized) lead to three major conclusions. (A) k(po) differences are dominated by capillary water permeability (P(W)(†)), not size, differences. NWM and NGM voxel k(po) and v(b) values are independent. Quantitative analyses of concomitant population-averaged k(po), v(b) variations in normal and normal-appearing MS brain ROIs confirm P(W)(†) dominance. (B) P(W)(†) is dominated (>95%) by a trans(endothelial)cellular pathway, not the P(CA)(†) paracellular route. In MS lesions and GBM tumors, P(CA)(†) increases but P(W)(†) decreases. (C) k(po) tracks steady-state ATP production/consumption flux per capillary. In normal, MS, and GBM brain, regional k(po) correlates with literature MRSI ATP (positively) and Na(+) (negatively) tissue concentrations. This suggests that the P(W)(†) pathway is metabolically active. Excellent agreement of the relative NGM/NWM k(po)v(b) product ratio with the literature (31)PMRSI-MT CMR(oxphos) ratio confirms the flux property. We have previously shown that the cellular water molecule efflux rate constant (k(io)) is proportional to plasma membrane P-type ATPase turnover, likely due to active trans-membrane water cycling. With synaptic proximities and synergistic metabolic cooperativities, polar brain endothelial, neuroglial, and neuronal cells form "gliovascular units." We hypothesize that a chain of water cycling processes transmits brain metabolic activity to k(po), letting it report neurogliovascular unit Na(+),K(+)-ATPase activity. Cerebral k(po) maps represent metabolic (functional) neuroimages. The NGM 2.9 s(-1) k(po) means an equilibrium unidirectional water efflux of ~10(15) H2O molecules s(-1) per capillary (in 1 μL tissue): consistent with the known ATP consumption rate and water co-transporting membrane symporter stoichiometries.

The cost of multiple sclerosis drugs in the US and the pharmaceutical industry: Too big to fail?

Objective:

To examine the pricing trajectories in the United States of disease-modifying therapies (DMT) for multiple sclerosis (MS) over the last 20 years and assess the influences on rising prices.

Methods:

We estimated the trend in annual drug costs for 9 DMTs using published drug pricing data from 1993 to 2013. We compared changes in DMT costs to general and prescription drug inflation during the same period. We also compared the cost trajectories for first-generation MS DMTs interferon (IFN)–β-1b, IFN-β-1a IM, and glatiramer acetate with contemporaneously approved biologic tumor necrosis factor (TNF) inhibitors.

Results:

First-generation DMTs, originally costing $8,000 to $11,000, now cost about $60,000 per year. Costs for these agents have increased annually at rates 5 to 7 times higher than prescription drug inflation. Newer DMTs commonly entered the market with a cost 25%–60% higher than existing DMTs. Significant increases in the cost trajectory of the first-generation DMTs occurred following the Food and Drug Administration approvals of IFN-β-1a SC (2002) and natalizumab (reintroduced 2006) and remained high following introduction of fingolimod (2010). Similar changes did not occur with TNF inhibitor biologics during these time intervals. DMT costs in the United States currently are 2 to 3 times higher than in other comparable countries.

Conclusions:

MS DMT costs have accelerated at rates well beyond inflation and substantially above rates observed for drugs in a similar biologic class. There is an urgent need for clinicians, payers, and manufacturers in the United States to confront the soaring costs of DMTs.

Japanese macaque encephalomyelitis: a spontaneous multiple sclerosis-like disease in a nonhuman primate

OBJECTIVE

To describe Japanese macaque encephalomyelitis (JME), a spontaneous inflammatory demyelinating disease occurring in the Oregon National Primate Research Center's (ONPRC) colony of Japanese macaques (JMs, Macaca fuscata).

METHODS

JMs with neurologic impairment were removed from the colony, evaluated, and treated with supportive care. Animals were humanely euthanized and their central nervous systems (CNSs) were examined.

RESULTS

ONPRC's JM colony was established in 1965 and no cases of JME occurred until 1986. Since 1986, 57 JMs spontaneously developed a disease characterized clinically by paresis of 1 or more limbs, ataxia, or ocular motor paresis. Most animals were humanely euthanized during their initial episode. Three recovered, later relapsed, and were then euthanized. There was no gender predilection and the median age for disease was 4 years. Magnetic resonance imaging of 8 cases of JME revealed multiple gadolinium-enhancing T(1) -weighted hyperintensities in the white matter of the cerebral hemispheres, brainstem, cerebellum, and cervical spinal cord. The CNS of monkeys with JME contained multifocal plaque-like demyelinated lesions of varying ages, including acute and chronic, active demyelinating lesions with macrophages and lymphocytic periventricular infiltrates, and chronic, inactive demyelinated lesions. A previously undescribed gamma-herpesvirus was cultured from acute JME white matter lesions. Cases of JME continue to affect 1% to 3% of the ONPRC colony per year.

INTERPRETATION

JME is a unique spontaneous disease in a nonhuman primate that has similarities with multiple sclerosis (MS) and is associated with a novel simian herpesvirus. Elucidating the pathogenesis of JME may shed new light on MS and other human demyelinating diseases.

Lipoic acid stimulates cAMP production via G protein-coupled receptor-dependent and -independent mechanisms

Lipoic acid (LA) is a naturally occurring fatty acid that exhibits anti-oxidant and anti-inflammatory properties and is being pursued as a therapeutic for many diseases including multiple sclerosis, diabetic polyneuropathy and Alzheimer's disease. We previously reported on the novel finding that racemic LA (50:50 mixture of R-LA and S-LA) stimulates cAMP production, activates prostanoid EP2 and EP4 receptors and adenylyl cyclases (AC), and suppresses activation and cytotoxicity in NK cells. In this study, we present evidence that furthers our understanding of the mechanisms of action of LA. Using various LA derivatives, such as dihydrolipoic acid (DHLA), S,S-dimethyl lipoic acid (DMLA) and lipoamide (LPM), we discovered that only LA is capable of stimulating cAMP production in NK cells. Furthermore, there is no difference in cAMP production after stimulation with either R-LA, S-LA or racemic LA. Competition and synergistic studies indicate that LA may also activate AC independent of the EP2 and EP4 receptors. Pretreatment of PBMCs with KH7 (a specific peptide inhibitor of soluble AC) and the calcium inhibitor (Bapta) prior to LA treatment resulted in reduced cAMP levels, suggesting that soluble AC and calcium signaling mediate LA stimulation of cAMP production. In addition, pharmacological inhibitor studies demonstrate that LA also activates other G protein-coupled receptors, including histamine and adenosine but not the β-adrenergic receptors. These novel findings provide information to better understand the mechanisms of action of LA, which can help facilitate the use of LA as a therapeutic for various diseases.

Lipoic acid attenuates inflammation via cAMP and protein kinase A signaling

Background

Abnormal regulation of the inflammatory response is an important component of diseases such as diabetes, Alzheimer's disease and multiple sclerosis (MS). Lipoic acid (LA) has been shown to have antioxidant and anti-inflammatory properties and is being pursued as a therapy for these diseases. We first reported that LA stimulates cAMP production via activation of G-protein coupled receptors and adenylyl cyclases. LA also suppressed NK cell activation and cytotoxicity. In this study we present evidence supporting the hypothesis that the anti-inflammatory properties of LA are mediated by the cAMP/PKA signaling cascade. Additionally, we show that LA oral administration elevates cAMP levels in MS subjects.

Methodology/Principal Findings

We determined the effects of LA on IL-6, IL-17 and IL-10 secretion using ELISAs. Treatment with 50 µg/ml and 100 µg/ml LA significantly reduced IL-6 levels by 19 and 34%, respectively, in T cell enriched PBMCs. IL-17 levels were also reduced by 35 and 50%, respectively. Though not significant, LA appeared to have a biphasic effect on IL-10 production. Thymidine incorporation studies showed LA inhibited T cell proliferation by 90%. T-cell activation was reduced by 50% as measured by IL-2 secretion. Western blot analysis showed that LA treatment increased phosphorylation of Lck, a downstream effector of protein kinase A. Pretreatment with a peptide inhibitor of PKA, PKI, blocked LA inhibition of IL-2 and IFN gamma production, indicating that PKA mediates these responses. Oral administration of 1200 mg LA to MS subjects resulted in increased cAMP levels in PBMCs four hours after ingestion. Average cAMP levels in 20 subjects were 43% higher than baseline.

Conclusions/Significance

Oral administration of LA in vivo resulted in significant increases in cAMP concentration. The anti-inflammatory effects of LA are mediated in part by the cAMP/PKA signaling cascade. These novel findings enhance our understanding of the mechanisms of action of LA.

Clinical trial of a formal group fatigue program in multiple sclerosis

Fatigue: Take Control is a novel program to teach fatigue management to people with multiple sclerosis (MS) following recommendations in the Fatigue and Multiple Sclerosis guideline. Fatigue: Take Control includes six 2-hour group sessions with DVD viewing, discussion and homework and accompanying participant and leader workbooks. While many people have participated in Fatigue: Take Control programs, its efficacy has not been determined. The objective of this study was to determine whether participation in Fatigue: Take Control reduces fatigue and increases self-efficacy in people with MS. Thirty participants were randomly assigned to a group who immediately participated in the program (FTC) or a wait-list group (WL). The primary outcome was the Modified Fatigue Impact Scale (MFIS) and secondary outcomes were the Multiple Sclerosis Self-Efficacy Scale (MSSE) and the Fatigue Severity Scale (FSS). The MFIS was administered on 10 occasions. Other measures were administered on four occasions. A mixed model tested the effects using all observations. Compared with the WL, the FTC group had significantly more improvement on the MFIS [F(1, 269) = 7.079, p = 0.008] and the MSSE [F(1, 111) = 5.636, p = 0.019]. No significant effect was found for the FSS. Across all visits, fatigue was significantly lower and self-efficacy was significantly higher for the FTC group compared with the WL group. This pilot study demonstrated significant effects in fatigue and self-efficacy among subjects taking the Fatigue: Take Control program, suggesting that this comprehensive program based on the Fatigue and Multiple Sclerosis guideline may be beneficial in MS.

Pharmacokinetic study of lipoic acid in multiple sclerosis: comparing mice and human pharmacokinetic parameters

Lipoic acid is a natural antioxidant available as an oral supplement from a number of different manufacturers. Lipoic acid administered subcutaneously is an effective therapy for murine experimental autoimmune encephalomyelitis, a model of multiple sclerosis. The aim of this study was to compare serum lipoic acid levels with oral dosing in patients with multiple sclerosis with serum levels in mice receiving subcutaneous doses of lipoic acid. We performed serum pharmacokinetic studies in patients with multiple sclerosis after a single oral dose of 1200 mg lipoic acid. Patients received one of the three different racemic formulations randomly: tablet (Formulation A) and capsules (Formulations B and C). Mice pharmacokinetic studies were performed with three different subcutaneous doses (20, 50 and 100 mg/kg racemic lipoic acid). The pharmacokinetic parameters included Maximum Serum Concentrations (C(max) in microg/ml) and area under the curve (0-infinity) (AUC ( 0-infinity) in microg*min/ml). We found mean C(max) and AUC (0-infinity) in patients with multiple sclerosis as follows: group A (N = 7) 3.8 +/- 2.6 and 443.1 +/- 283.9; group B (N = 8) 9.9 +/- 4.5 and 745.2 +/- 308.7 and group C (N = 8) 10.3 +/- 3.8 and 848.8 +/- 360.5, respectively. Mean C(max) and AUC (0-infinity) in the mice were: 100 mg/kg lipoic acid: 30.9 +/- 2.9 and 998 +/- 245; 50 mg/kg lipoic acid: 7.6 +/- 1.4 and 223 +/- 20; 20 mg/kg lipoic acid: 2.7 +/- 0.7 and 119 +/- 33. We conclude that patients taking 1200 mg of lipoic acid from two of the three oral formulations achieved serum C(max) and AUC levels comparable to that observed in mice receiving 50 mg/kg subcutaneous dose of lipoic acid, which is a highly therapeutic dose in experimental autoimmune encephalomyelitis. A dose of 1200 mg oral lipoic acid can achieve therapeutic serum levels in patients with multiple sclerosis.

Lipoic acid stimulates cAMP production via the EP2 and EP4 prostanoid receptors and inhibits IFN gamma synthesis and cellular cytotoxicity in NK cells

The antioxidant lipoic acid (LA) treats and prevents the animal model of multiple sclerosis (MS), experimental autoimmune encephalomyelitis (EAE). In an effort to understand the therapeutic potential of LA in MS, we sought to define the cellular mechanisms that mediate the effects of LA on human natural killer (NK) cells, which are important in innate immunity as the first line of defense against invading pathogens and tumor cells. We discovered that LA stimulates cAMP production in NK cells in a dose-dependent manner. Studies using pharmacological inhibitors and receptor transfection experiments indicate that LA stimulates cAMP production via activation of the EP2 and EP4 prostanoid receptors and adenylyl cyclase. In addition, LA suppressed interleukin (IL)-12/IL-18 induced IFNgamma secretion and cytotoxicity in NK cells. These novel findings suggest that LA may inhibit NK cell function via the cAMP signaling pathway.

Therapeutic vaccination with a trivalent T-cell receptor (TCR) peptide vaccine restores deficient FoxP3 expression and TCR recognition in subjects with multiple sclerosis

Therapeutic vaccination using T-cell receptor (TCR) peptides from V genes commonly expressed by potentially pathogenic T cells remains an approach of interest for treatment of multiple sclerosis (MS) and other autoimmune diseases. We developed a trivalent TCR vaccine containing complementarity determining region (CDR) 2 peptides from BV5S2, BV6S5 and BV13S1 emulsified in incomplete Freund's adjuvant that reliably induced high frequencies of TCR-specific T cells. To evaluate induction of regulatory T-cell subtypes, immunological and clinical parameters were followed in 23 treatment-naïve subjects with relapsing-remitting or progressive MS who received 12 monthly injections of the trivalent peptide vaccine over 1 year in an open-label study design. Prior to vaccination, subjects had reduced expression of forkhead box (Fox) P3 message and protein, and reduced recognition of the expressed TCR repertoire by TCR-reactive cells compared with healthy control donors. After three or four injections, most vaccinated MS subjects developed high frequencies of circulating interleukin (IL)-10-secreting T cells specific for the injected TCR peptides and significantly enhanced expression of FoxP3 by regulatory T cells present in both 'native' CD4+ CD25+ and 'inducible' CD4+ CD25- peripheral blood mononuclear cells (PBMC). At the end of the trial, PBMC from vaccinated MS subjects retained or further increased FoxP3 expression levels, exhibited significantly enhanced recognition of the TCR V gene repertoire apparently generated by perturbation of the TCR network, and significantly suppressed neuroantigen but not recall antigen responses. These findings demonstrate that therapeutic vaccination using only three commonly expressed BV gene determinants can induce an expanded immunoregulatory network in vivo that may optimally control complex autoreactive responses that characterize the inflammatory phase of MS.

Cognition and fatigue in multiple sclerosis: Potential effects of medications with central nervous system activity

To evaluate the potential effects of medications with central nervous system (CNS) activity on cognitive function and fatigue in multiple sclerosis (MS), we performed a retrospective analysis of medication use among 70 subjects with MS who were participating in a clinical trial for evaluation of the effects of yoga and exercise programs on cognition and fatigue. Among these MS subjects, 74% were taking at least one potentially CNS-active medication. These 70 subjects were divided into two groups: those taking at least one CNS-active medication (n = 52) and those not on any medications with potential CNS activity (n = 18). We compared assessments of cognitive function and fatigue using an analysis of covariance. MS subjects on CNS-active medication had greater impairment on measures of processing speed, sustained attention, and fatigue than those not on these medications. While these findings do not establish a causal relationship between medication use and cognitive impairment and fatigue, the data indicate that researchers need to control for use of CNS-active medications when conducting studies of cognitive impairment and fatigue in MS subjects.