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Featured researches published by John R. Richert.


Arthritis & Rheumatism | 2001

Demyelination occurring during anti-tumor necrosis factor ? therapy for inflammatory arthritides

Niveditha Mohan; Evelyne T. Edwards; Thomas R. Cupps; Patrick J. Oliverio; Glenn D. Sandberg; Heidi Crayton; John R. Richert; Jeffrey N. Siegel

OBJECTIVE To review the occurrence of neurologic events suggestive of demyelination during anti-tumor necrosis factor alpha (anti-TNFalpha) therapy for inflammatory arthritides. METHODS The Adverse Events Reporting System of the Food and Drug Administration (FDA) was queried following a report of a patient with refractory rheumatoid arthritis who developed confusion and difficulty with walking after receiving etanercept for 4 months. RESULTS Nineteen patients with similar neurologic events were identified from the FDA database, 17 following etanercept administration and 2 following infliximab administration for inflammatory arthritis. All neurologic events were temporally related to anti-TNFalpha therapy, with partial or complete resolution on discontinuation. One patient exhibited a positive rechallenge phenomenon. CONCLUSION Further surveillance and studies are required to better define risk factors for and frequency of adverse events and their relationship to anti-TNFalpha therapies. Until more long-term safety data are available, consideration should be given to avoiding anti-TNFalpha therapy in patients with preexisting multiple sclerosis and to discontinuing anti-TNFalpha therapy immediately when new neurologic signs and symptoms occur, pending an appropriate evaluation.


Neurology | 1998

Incidence and significance of neutralizing antibodies to interferon beta-1a in multiple sclerosis

Richard A. Rudick; Nancy Simonian; J. A. Alam; Marilyn Campion; J. O. Scaramucci; W. Jones; Michael E. Coats; Donald E. Goodkin; Bianca Weinstock-Guttman; Robert M. Herndon; Michele Mass; John R. Richert; Andres M. Salazar; Frederick Munschauer; Diane Cookfair; Jack H. Simon; Lawrence Jacobs

Background: Interferon beta is an effective treatment for relapsing multiple sclerosis(MS). As with other protein drugs, neutralizing antibodies (NAB) can develop that reduce the effectiveness of treatment. Objectives: To determine the incidence and biological significance of NAB to interferon beta-1a (IFN-β-1a; Avonex; Biogen, Cambridge, MA) in MS patients. Methods: A two-step assay for NAB to IFN-β-1a was developed and used to assay serum samples from participants in the phase III clinical trial of IFN-β-1a, and from patients in an ongoing open-label study of IFN-β1a. The biological significance of NAB to IFN-β-1a was determined by relating the NAB assay result to in vivo induction of the IFN-inducible molecules neopterin and β-2 microglobulin, and the clinical significance was determined by comparing clinical and MRI measures of disease activity after 2 years of IFN-β-1a therapy in patients who were NAB+ and NAB-. The incidence of NAB was compared in MS patients who had used only IFN-β-1a with the incidence in MS patients who had used only IFN-β-1b. Results: In patients in the open-label study, development of NAB to IFN-β-1a resulted in a titer-dependent reduction in neopterin induction after interferon injections. In patients in the phase III study, development of NAB was associated with a reduction in β-2 microglobulin induction. In the phase III study, a trend toward reduced benefit of IFN-β-1a on MRI activity in NAB+ versus NAB- patients was observed. The incidence of NAB to IFN-β-1a in the open-label study was approximately 5% over 24 months of treatment of IFN-β-1a therapy, but was four- to sixfold higher using the same assay for patients exposed only to IFN-β-1b for a similar duration. There were no clinical, MRI, or CSF characteristics that were predictive of which patients would develop NAB. Conclusions: NAB directed against IFN-β have in vivo biological consequences in patients with MS. The frequency with which MS patients develop NAB against IFN-β is significantly greater with IFN-β-1b therapy compared with IFN-β-1a therapy. Treatment decisions in MS patients treated withIFN-β should take into account development of NAB.


Neurology | 1999

A longitudinal study of brain atrophy in relapsing multiple sclerosis

Jack H. Simon; Lawrence Jacobs; Marilyn Campion; Richard A. Rudick; Diane Cookfair; Robert M. Herndon; John R. Richert; Andres M. Salazar; Jill S. Fischer; Donald E. Goodkin; Nancy Simonian; M. Lajaunie; D. Miller; Karl Wende; A. Martens-Davidson; R. P. Kinkel; Frederick Munschauer; Carol M. Brownscheidle

Objective: To determine if progressive brain atrophy could be detected over 1- and 2-year intervals in relapsing MS, based on annual MR studies from the Multiple Sclerosis Collaborative Research Group (MSCRG) trial of interferon β-1a (Avonex). Methods: All subjects had mild to moderate disability, with baseline expanded disability status scores ranging from 1.0 to 3.5, and at least two relapses in the 3 years before study entry. Atrophy measures included third and lateral ventricle width, brain width, and corpus callosum area. Results: Significant increases were detected in third ventricle width at year 2 and lateral ventricle width at 1 and 2 years. Significant decreases in corpus callosum area and brain width were also observed at 1 and 2 years. Multiple regression analyses suggested that the number of gadolinium-enhancing lesions at baseline was the single significant contributor to change in third ventricle width. Atrophy over 1 and 2 years as indicated by enlargement of the third and lateral ventricle and shrinkage of the corpus callosum was greater for patients entering the trial with enhancing lesions. Greater disability increments over 1 and 2 years were associated with more severe third ventricle enlargement. Conclusion: In patients with relapsing MS and only mild to moderate disability, significant cerebral atrophy is already developing that can be measured over periods of only 1 to 2 years. The course of cerebral atrophy in MS appears to be influenced by prior inflammatory disease activity as indicated by the presence of enhancing lesions. Brain atrophy measures are important markers of MS disease progression because they likely reflect destructive and irreversible pathologic processes.


Annals of Neurology | 2000

Neuropsychological effects of interferon β-1a in relapsing multiple sclerosis

Jill S. Fischer; Roger L. Priore; Lawrence Jacobs; Diane Cookfair; Richard A. Rudick; Robert M. Herndon; John R. Richert; Andres M. Salazar; Donald E. Goodkin; Carl V. Granger; Jack H. Simon; Jordan Grafman; Muriel D. Lezak; Kathleen M. Hovey; Katherine Kawczak Perkins; Danielle Barilla-Clark; Mark Schacter; David W. Shucard; Anna L. Davidson; Karl Wende; Dennis Bourdette; Mariska Kooijmans-Coutinho

Cognitive dysfunction is common in multiple sclerosis (MS), yet few studies have examined effects of treatment on neuropsychological (NP) performance. To evaluate the effects of interferon β‐1a (IFNβ‐1a, 30 μg administered intramuscularly once weekly [Avonex]) on cognitive function, a Comprehensive NP Battery was administered at baseline and week 104 to relapsing MS patients in the phase III study, 166 of whom completed both assessments. A Brief NP Battery was also administered at 6‐month intervals. The primary NP outcome measure was 2‐year change on the Comprehensive NP Battery, grouped into domains of information processing and learning/memory (set A), visuospatial abilities and problem solving (set B), and verbal abilities and attention span (set C). NP effects were most pronounced in cognitive domains vulnerable to MS: IFNβ‐1a had a significant beneficial effect on the set A composite, with a favorable trend evident on set B. Secondary outcome analyses revealed significant between‐group differences in slopes for Brief NP Battery performance and time to sustained deterioration in a Paced Auditory Serial Addition Test processing rate, favoring the IFNβ‐1a group. These results support and extend previous observations of significant beneficial effects of IFNβ‐1a for relapsing MS. Ann Neurol 2000;48:885–892


Neurology | 2000

A longitudinal study of T1 hypointense lesions in relapsing MS MSCRG trial of interferon β-1a

Jack H. Simon; J. Lull; Lawrence Jacobs; Richard A. Rudick; Diane Cookfair; Robert M. Herndon; John R. Richert; Andres M. Salazar; Jeanelle Sheeder; D. Miller; K. McCabe; A. Serra; Marilyn Campion; Jill S. Fischer; Donald E. Goodkin; Nancy Simonian; M. Lajaunie; Karl Wende; A. Martens-Davidson; R. P. Kinkel; Frederick Munschauer

Background: T1 hypointense lesions (T1 black holes) are focal areas of relatively severe CNS tissue damage detected by MRI in patients with MS. Objective: To determine the natural history of T1 hypointense lesions in relapsing MS and the utility of T1 hypointense lesions as outcome measures in MS clinical trials. Methods: MR studies were from the Multiple Sclerosis Collaborative Research Group trial. Longitudinal results are reported in 80 placebo- and 80 interferon β-1a (IFNβ-1a)–treated patients with mild to moderate disability relapsing-remitting MS. Results: There was a small but significant correlation between T1 hypointense lesion volume and disability at baseline and on trial (r = 0.22, r = 0.28). In placebo patients there was a 29.2% increase in the mean volume of T1 hypointense lesions (median 124.5 mm3) over 2 years (p < 0.001 for change from baseline), as compared to an 11.8% increase (median 40 mm3) in the IFNβ-1a–treated patients (change from baseline not significant). These treatment group comparisons did not quite reach significance. The most significant contributor to change in T1 hypointense lesions was the baseline number of enhancing lesions (model r2 = 0.554). Placebo patients with more active disease, defined by enhancing lesions at baseline, were the only group to show a significant increase in T1 hypointense lesion volume from baseline. Conclusion: The development of T1 hypointense lesions is strongly influenced by prior inflammatory disease activity, as indicated by enhancing lesions. These results suggest that treatment with once weekly IM IFNβ-1a (30 mcg) slows the 2-year accumulation of these lesions in the brain.


Multiple Sclerosis Journal | 1998

Human Herpesvirus-6 (HHV-6) infection in multiple sclerosis: a preliminary report

Dharam V. Ablashi; W Lapps; Mark H. Kaplan; J E Whitman; John R. Richert; Gary R. Pearson

We examined cerebra! spinal fluid (CSF) from multiple sclerosis (MS) patients and patients with other neurological diseases (OND) for antibody specific for Human Herpesvirus-6 (HHV-6) and for HHV-6 DNA detectable by PCR. CSF from MS patients had a higher frequency of IgG antibody to HHV-6 late antigens (39.4%) compared with CSF from OND (7.4%). In contrast, the frequency of detectable IgG antibody in CSF from MS patients specific for Epstein-Barr Virus (EBV) (12.1%) and Human Cytomegalovirus (HCMV) (6.1%) was much lower. Two of 12 MS CSFs (16.7%) also contained HHV-6 DNA detected by PCR. None of four OND CSF were positive for HHV-6 DNA. Plasma from 16 patients with MS, eight with OND and 72 healthy donors were tested for antibodies by ELISA to HHV-6 early (p41/38) and late (gp 110) proteins. Although no differences in ant-gp 110 IgG antibody were detected between MS patients, patients with other neurological diseases, and normals, IgG antibody to early protein p41/38 was detected in > 68% of the plasma from MS patients, 12.5% from OND patient and 27.8% of the controls. IgM antibody to p41/38 was present in >56% of MS patients, 12.5% of OND patients, and 19% of controls. These data suggest that more than half of the MS patients had active, ongoing HHV-6 infections. HHV-6 was also isolated from peripheral blood mononuclear cells (PBMC) from 3/5 MS patients who were in relapse or had progressive disease and was identified as HHV-6 Variant B. These preliminary results support the hypothesis that HHV-6 may be a co-factor in the pathogenesis of some cases of MS.


Multiple Sclerosis Journal | 1997

Open label gabapentin treatment for pain in multiple sclerosis.

Maria K. Houtchens; John R. Richert; Arif Sami; John Rose

Pain is a frequent and distressing complaint in patients with multiple sclerosis (MS) and may present a difficult therapeutic problem. Conventional therapy is moderately effective and includes, among others, a variety of anticonvulsant medications. Gabapentin (Neurontin™) is a new generation antiepileptic drug which appears to be advantageous in treatment of intractable pain of reflex sympathetic dystrophy. This study investigates the benefits of open-label treatment with gabapentin for pain control in 25 patients with MS. Excellent to moderate pain relief was obtained in a substantial number of patients. Throbbing pains, pins and needles, and cramping pains responded best, and dull aching pains responded least to the medication. There was no significant change in distribution and type of pain as a result of this treatment Mild to moderate side effects were observed. Cautious escalation of the dose of gabapentin is advisable in MS patients. Further clinical trials with larger patient groups are recommended.


Journal of Neuroimmunology | 1999

Cerebrospinal fluid abnormalities in a phase III trial of Avonex® (IFNβ-1a) for relapsing multiple sclerosis

Richard A. Rudick; Diane Cookfair; Nancy Simonian; Richard M. Ransohoff; John R. Richert; Lawrence Jacobs; Robert M. Herndon; Andres M. Salazar; Jill S. Fischer; Carl V. Granger; Donald E. Goodkin; Jack H. Simon; David M. Bartoszak; Dennis Bourdette; Jonathan Braiman; Carol M. Brownscheidle; Michael E. Coats; Stanley Cohan; David S. Dougherty; R. P. Kinkel; Michele Mass; Frederick E. Munchsauer; Kathy O'Reilly; Roger L. Priore; Patrick M. Pullicino; Barbara J. Scherokman; Karl Wende; Bianca Weinstock-Guttman; Ruth H. Whitham

Abstract Background and objective : This report provides results of CSF analyses done in a subset of relapsing remitting MS patients participating in a placebo-controlled, double-blind, phase III clinical trial of IFNβ-Studies supported by the National Multiple Sclerosis Society (grants RG2019, RG2827),a (Avonex®, Biogen). The clinical trial demonstrated that IFNβ-1a treatment resulted in significantly reduced disability progression, annual relapse rate, and new brain lesions visualized by cranial magnetic resonance imaging. The objectives of the current study were to determine: (a) whether CSF abnormalities in MS patients correlated with disease or MRI characteristics, and (b) effects of IFNβ-1a therapy on these CSF abnormalities. Methods : CSF was analyzed from 262 (87%) of the 301 study subjects at entry into the clinical trial, and a second CSF sample was analyzed from 137 of these 262 subjects after 2 years of therapy. CSF cell counts, oligoclonal bands (OCB), IgG index, and free kappa light chains were measured using standard assays. Baseline CSF results were compared with demographic, disease, and MRI parameters. Differences in on-study relapse rate, gadolinium enhancement, and EDSS change according to baseline CSF status was used to determine the predictive value of CSF for subsequent clinical and MRI disease activity. Change in CSF parameters after 104 weeks were used to determine the effects of treatment. Results : (1) At study baseline, 37% of the subjects had abnormal CSF WBC counts, 61% had abnormal levels of CSF free kappa light chains, 84% had abnormal IgG index values, and 90% were positive for OCB. (2) Baseline IgG index, kappa light chains, and OCB showed weakly positive, statistically significant correlations with Gd-enhanced lesion volume and T2 lesion volume. WBC showed a statistically significant correlation with Gd-enhancing lesion volume but was uncorrelated with T2 lesion volume. (3) There was an associated between baseline CSF WBC counts and on-study clinical and MRI disease activity in placebo recipients. (4) IFNβ-1a treatment resulted in significantly reduced CSF WBC counts, but there was no treatment-related change in CSF IgG index, kappa light chains, or OCB, which remained relatively stable over time in both patient groups. Conclusions : The current study documents significant reductions in CSF WBC counts in patients treated with IFNβ-1a for 104 weeks. This finding is considered relevant to the therapeutic response, since CSF WBC counts were found to be positively correlated with subsequent clinical and MRI disease activity in placebo-treated relapsing MS patients.BACKGROUND AND OBJECTIVE This report provides results of CSF analyses done in a subset of relapsing remitting MS patients participating in a placebo-controlled, double-blind, phase III clinical trial of IFNbeta-Studies supported by the National Multiple Sclerosis Society (grants RG2019, RG2827),a (Avonex , Biogen). The clinical trial demonstrated that IFNbeta-1a treatment resulted in significantly reduced disability progression, annual relapse rate, and new brain lesions visualized by cranial magnetic resonance imaging. The objectives of the current study were to determine: (a) whether CSF abnormalities in MS patients correlated with disease or MRI characteristics, and (b) effects of IFNbeta-1a therapy on these CSF abnormalities. METHODS CSF was analyzed from 262 (87%) of the 301 study subjects at entry into the clinical trial, and a second CSF sample was analyzed from 137 of these 262 subjects after 2 years of therapy. CSF cell counts, oligoclonal bands (OCB), IgG index, and free kappa light chains were measured using standard assays. Baseline CSF results were compared with demographic, disease, and MRI parameters. Differences in on-study relapse rate, gadolinium enhancement, and EDSS change according to baseline CSF status was used to determine the predictive value of CSF for subsequent clinical and MRI disease activity. Change in CSF parameters after 104 weeks were used to determine the effects of treatment. RESULTS (1) At study baseline, 37% of the subjects had abnormal CSF WBC counts, 61% had abnormal levels of CSF free kappa light chains, 84% had abnormal IgG index values, and 90% were positive for OCB. (2) Baseline IgG index, kappa light chains, and OCB showed weakly positive, statistically significant correlations with Gd-enhanced lesion volume and T2 lesion volume. WBC showed a statistically significant correlation with Gd-enhancing lesion volume but was uncorrelated with T2 lesion volume. (3) There was an associated between baseline CSF WBC counts and on-study clinical and MRI disease activity in placebo recipients. (4) IFNbeta-1a treatment resulted in significantly reduced CSF WBC counts, but there was no treatment-related change in CSF IgG index, kappa light chains, or OCB, which remained relatively stable over time in both patient groups. CONCLUSIONS The current study documents significant reductions in CSF WBC counts in patients treated with IFNbeta-1a for 104 weeks. This finding is considered relevant to the therapeutic response, since CSF WBC counts were found to be positively correlated with subsequent clinical and MRI disease activity in placebo-treated relapsing MS patients.


Journal of Neuroimmunology | 1989

Evidence for multiple human T cell recognition sites on myelin basic protein

John R. Richert; Eve D. Robinson; Gladys E. Deibler; Russell E. Martenson; Ljubo J. Dragovic; Marian W. Kies

Myelin basic protein (BP)-specific T cell clones were used to study human T cell recognition sites on the BP molecule. Proliferation assays performed with a panel of xenogeneic BPs of known amino acid sequence and with large peptide fragments of human and guinea pig BPs demonstrated ten different patterns of reactivity. The data provide evidence for at least four different human T cell epitopes within the C-terminal half of the BP molecule, three within the N-terminal half, and three located within the central portion of the molecule. The results indicate that attempts to inhibit anti-BP responses in vivo in an antigen-specific manner will require the suppression of multiple T cell populations.


Neurology | 2002

Immunization and MS A summary of published evidence and recommendations

Olivier T. Rutschmann; Douglas C McCrory; David B. Matchar; Dennis Bourdette; Lois Copperman; Patricia K. Coyle; Frank DeStafano; Thomas Marrie; Deborah Miller; Cindy Phair; John R. Richert; Douglas S. Goodin; Carmel Armon; Elliot M. Frohman; Robert S. Goldman; David Hammond; Chung Y. Hsu; Andres M. Kanner; David S. Lefkowitz; Isaac E. Silverman; Michael A. Sloan; Yuen T. So

Objective To review the risk of MS exacerbations after infectious episodes potentially preventable by vaccination, and the risks and benefits of immunizing patients with MS. Methods The authors searched MEDLINE (1966 to January 2001; U.S. National Library of Medicine, Bethesda, MD), HealthSTAR, and Cumulative Index to Nursing and Allied Health Literature (CINAHL) database (Cinahl Information Systems, Glendale, CA) for English-language articles. Each study was summarized and rated for quality of evidence. Then feasible data were pooled and analyzed in meta-analysis. Results The risk of contracting common infectious diseases in patients with MS is not well established. There is strong evidence for an increased risk of MS exacerbations during weeks around an infectious episode. There is strong evidence against an increased risk of MS exacerbation after influenza immunization. There is no evidence that hepatitis B, varicella, tetanus, or Bacille Calmette–Guerin vaccines increase the risk of MS exacerbations. Insufficient evidence was found for other vaccines. Conclusions Evidence supports 1) strategies to minimize the risk of acquiring infectious diseases that may trigger exacerbations of MS; and 2) the safety of using influenza, hepatitis B, varicella, tetanus, and Bacille Calmette–Guerin (BCG) vaccines in patients with MS.

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Henry F. McFarland

National Institutes of Health

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Andres M. Salazar

Walter Reed Army Institute of Research

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Eve D. Robinson

Georgetown University Medical Center

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Robert M. Herndon

Johns Hopkins University School of Medicine

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Dale E. McFarlin

National Institutes of Health

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Jack H. Simon

University of Colorado Denver

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