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Dive into the research topics where K Rammohan is active.

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Featured researches published by K Rammohan.


Lancet Neurology | 2014

Safety and efficacy of fingolimod in patients with relapsing-remitting multiple sclerosis (FREEDOMS II): a double-blind, randomised, placebo-controlled, phase 3 trial

Peter A. Calabresi; Ernst Wilhelm Radue; Douglas S. Goodin; K Rammohan; Anthony T. Reder; Timothy Vollmer; Mark A. Agius; Ludwig Kappos; Tracy Stites; Bingbing Li; Linda Cappiello; Philipp von Rosenstiel; Fred D. Lublin

BACKGROUND Fingolimod has shown reductions in clinical and MRI disease activity in patients with relapsing-remitting multiple sclerosis. We further assessed the efficacy and safety of fingolimod in such patients. METHODS We did this placebo-controlled, double-blind phase 3 study predominantly in the USA (101 of 117 centres). Using a computer-generated sequence, we randomly allocated eligible patients-those aged 18-55 years with relapsing-remitting multiple sclerosis-to receive fingolimod 0·5 mg, fingolimod 1·25 mg, or placebo orally once daily (1:1:1; stratified by study centre). On Nov 12, 2009, all patients assigned to fingolimod 1·25 mg were switched to the 0·5 mg dose in a blinded manner after a review of data from other phase 3 trials and recommendation from the data and safety monitoring board, but were analysed as being in the 1·25 mg group in the primary outcome analysis. Our primary endpoint was annualised relapse rate at month 24, analysed by intention to treat. Secondary endpoints included percentage brain volume change (PBVC) from baseline and time-to-disability-progression confirmed at 3 months. This trial is registered with ClinicalTrilals.gov, number NCT00355134. FINDINGS Between June 30, 2006, and March 4, 2009, we enrolled and randomly allocated 1083 patients: 370 to fingolimod 1·25 mg, 358 to fingolimod 0·5 mg, and 355 to placebo. Mean annualised relapse rate was 0·40 (95% CI 0·34-0·48) in patients given placebo and 0·21 (0·17-0·25) in patients given fingolimod 0·5 mg: rate ratio 0·52 (95% CI 0·40-0·66; p<0·0001), corresponding to a reduction of 48% with fingolimod 0·5 mg versus placebo. Mean PBVC was -0·86 (SD 1·22) for fingolimod 0·5 mg versus -1·28 (1·50) for placebo (treatment difference -0·41, 95% CI -0·62 to -0·20; p=0·0002). We recorded no statistically significant between-group difference in confirmed disability progression (hazard rate 0·83 with fingolimod 0·5 mg vs placebo; 95% CI 0·61-1·12; p=0·227). Fingolimod 0·5 mg caused more of the following adverse events versus placebo: lymphopenia (27 [8%] patients vs 0 patients), increased alanine aminotransferase (29 [8%] vs six [2%]), herpes zoster infection (nine [3%] vs three [1%]), hypertension (32 [9%] vs 11 [3%]), first-dose bradycardia (five [1%] vs one [<0·5%]), and first-degree atrioventricular block (17 [5%] vs seven [2%]). 53 (15%) of 358 patients given fingolimod 0·5 mg and 45 (13%) of 355 patients given placebo had serious adverse events over 24 months, which included basal-cell carcinoma (ten [3%] patients vs two [1%] patients), macular oedema (three [1%] vs two [1%]), infections (11 [3%] vs four [1%]), and neoplasms (13 [4%] vs eight [2%]). INTERPRETATION Our findings expand knowledge of the safety profile of fingolimod and strengthen evidence for its beneficial effects on relapse rates in patients with relapsing-remitting multiple sclerosis. We saw no effect of fingolimod on disability progression. Our findings substantiate the beneficial profile of fingolimod as a disease-modifying agent in the management of patients with relapsing-remitting multiple sclerosis. FUNDING Novartis Pharma AG.


The New England Journal of Medicine | 2017

Ocrelizumab versus Placebo in Primary Progressive Multiple Sclerosis

Xavier Montalban; Stephen L. Hauser; Ludwig Kappos; Douglas L. Arnold; Amit Bar-Or; Giancarlo Comi; Jérôme De Seze; Gavin Giovannoni; Hans-Peter Hartung; Bernhard Hemmer; Fred D. Lublin; K Rammohan; Krzysztof Selmaj; Anthony Traboulsee; Annette Sauter; Donna Masterman; Paulo Fontoura; Shibeshih Belachew; Hideki Garren; Nicole Mairon; Peter Chin; Jerry S. Wolinsky

BACKGROUND An evolving understanding of the immunopathogenesis of multiple sclerosis suggests that depleting B cells could be useful for treatment. We studied ocrelizumab, a humanized monoclonal antibody that selectively depletes CD20‐expressing B cells, in the primary progressive form of the disease. METHODS In this phase 3 trial, we randomly assigned 732 patients with primary progressive multiple sclerosis in a 2:1 ratio to receive intravenous ocrelizumab (600 mg) or placebo every 24 weeks for at least 120 weeks and until a prespecified number of confirmed disability progression events had occurred. The primary end point was the percentage of patients with disability progression confirmed at 12 weeks in a time‐to‐event analysis. RESULTS The percentage of patients with 12‐week confirmed disability progression was 32.9% with ocrelizumab versus 39.3% with placebo (hazard ratio, 0.76; 95% confidence interval [CI], 0.59 to 0.98; P=0.03). The percentage of patients with 24‐week confirmed disability progression was 29.6% with ocrelizumab versus 35.7% with placebo (hazard ratio, 0.75; 95% CI, 0.58 to 0.98; P=0.04). By week 120, performance on the timed 25‐foot walk worsened by 38.9% with ocrelizumab versus 55.1% with placebo (P=0.04); the total volume of brain lesions on T2‐weighted magnetic resonance imaging (MRI) decreased by 3.4% with ocrelizumab and increased by 7.4% with placebo (P<0.001); and the percentage of brain‐volume loss was 0.90% with ocrelizumab versus 1.09% with placebo (P=0.02). There was no significant difference in the change in the Physical Component Summary score of the 36‐Item Short‐Form Health Survey. Infusion‐related reactions, upper respiratory tract infections, and oral herpes infections were more frequent with ocrelizumab than with placebo. Neoplasms occurred in 2.3% of patients who received ocrelizumab and in 0.8% of patients who received placebo; there was no clinically significant difference between groups in the rates of serious adverse events and serious infections. CONCLUSIONS Among patients with primary progressive multiple sclerosis, ocrelizumab was associated with lower rates of clinical and MRI progression than placebo. Extended observation is required to determine the long‐term safety and efficacy of ocrelizumab. (Funded by F. Hoffmann–La Roche; ORATORIO ClinicalTrials.gov number, NCT01194570.)


The New England Journal of Medicine | 2017

Ocrelizumab versus Interferon Beta-1a in Relapsing Multiple Sclerosis

Stephen L. Hauser; Amit Bar-Or; Giancarlo Comi; Gavin Giovannoni; Hans-Peter Hartung; Bernhard Hemmer; Fred D. Lublin; Xavier Montalban; K Rammohan; Krzysztof Selmaj; Anthony Traboulsee; Jerry S. Wolinsky; Douglas L. Arnold; G. Klingelschmitt; Donna Masterman; Paulo Fontoura; Shibeshih Belachew; Peter Chin; Nicole Mairon; Hideki Garren; Ludwig Kappos; Opera I; Opera Ii Clinical Investigators

BACKGROUND B cells influence the pathogenesis of multiple sclerosis. Ocrelizumab is a humanized monoclonal antibody that selectively depletes CD20+ B cells. METHODS In two identical phase 3 trials, we randomly assigned 821 and 835 patients with relapsing multiple sclerosis to receive intravenous ocrelizumab at a dose of 600 mg every 24 weeks or subcutaneous interferon beta‐1a at a dose of 44 μg three times weekly for 96 weeks. The primary end point was the annualized relapse rate. RESULTS The annualized relapse rate was lower with ocrelizumab than with interferon beta‐1a in trial 1 (0.16 vs. 0.29; 46% lower rate with ocrelizumab; P<0.001) and in trial 2 (0.16 vs. 0.29; 47% lower rate; P<0.001). In prespecified pooled analyses, the percentage of patients with disability progression confirmed at 12 weeks was significantly lower with ocrelizumab than with interferon beta‐1a (9.1% vs. 13.6%; hazard ratio, 0.60; 95% confidence interval [CI], 0.45 to 0.81; P<0.001), as was the percentage of patients with disability progression confirmed at 24 weeks (6.9% vs. 10.5%; hazard ratio, 0.60; 95% CI, 0.43 to 0.84; P=0.003). The mean number of gadolinium‐enhancing lesions per T1‐weighted magnetic resonance scan was 0.02 with ocrelizumab versus 0.29 with interferon beta‐1a in trial 1 (94% lower number of lesions with ocrelizumab, P<0.001) and 0.02 versus 0.42 in trial 2 (95% lower number of lesions, P<0.001). The change in the Multiple Sclerosis Functional Composite score (a composite measure of walking speed, upper‐limb movements, and cognition; for this z score, negative values indicate worsening and positive values indicate improvement) significantly favored ocrelizumab over interferon beta‐1a in trial 2 (0.28 vs. 0.17, P=0.004) but not in trial 1 (0.21 vs. 0.17, P=0.33). Infusion‐related reactions occurred in 34.3% of the patients treated with ocrelizumab. Serious infection occurred in 1.3% of the patients treated with ocrelizumab and in 2.9% of those treated with interferon beta‐1a. Neoplasms occurred in 0.5% of the patients treated with ocrelizumab and in 0.2% of those treated with interferon beta‐1a. CONCLUSIONS Among patients with relapsing multiple sclerosis, ocrelizumab was associated with lower rates of disease activity and progression than interferon beta‐1a over a period of 96 weeks. Larger and longer studies of the safety of ocrelizumab are required. (Funded by F. Hoffmann–La Roche; OPERA I and II ClinicalTrials.gov numbers, NCT01247324 and NCT01412333, respectively.)


Multiple Sclerosis Journal | 2011

Safety and tolerability of cladribine tablets in multiple sclerosis: the CLARITY (CLAdRIbine Tablets treating multiple sclerosis orallY) study

Stuart D. Cook; Patrick Vermersch; Giancarlo Comi; Gavin Giovannoni; K Rammohan; Peter Rieckmann; P. Soelberg Sørensen; A Hamlett; M Miret; J Weiner; V Viglietta; B Musch; Steven J. Greenberg

Background: Cladribine is a synthetic deoxyadenosine analogue in development as an oral multiple sclerosis (MS) therapy. Objective: To report in detail the safety findings from the 96-week, phase III, double-blind CLARITY study, which evaluated treatment with cladribine tablets in relapsing–remitting MS. Methods: A total of 1,326 patients were randomized 1 : 1 : 1 to two short-course regimens of cladribine tablets (3.5 or 5.25 mg/kg cumulative dose over 96 weeks) or placebo. Safety assessments included monitoring for adverse events (AEs), routine physical and neurologic examinations and frequent laboratory parameter assessments. Results: Of the randomized patients, 88.6% completed treatment with cladribine tablets versus 86.3% with placebo. Lymphopenia was the most commonly reported AE in patients treated with cladribine tablets and was anticipated based on the mechanism of action. The incidence of infections was 48.3% with cladribine tablets and 42.5% with placebo, with 99.1% and 99.0% rated mild-to-moderate by investigators. Herpes zoster infections developed in 20 (2.3%) cladribine-treated patients; all cases were dermatomal. There were no herpes zoster infections in the placebo group. Nine (1.0%) patients experienced events related to uterine leiomyomas in the cladribine tablets groups versus one (0.2%) with placebo. Three isolated cases of malignancy were reported in cladribine-treated patients during the study; a fourth was reported during post-study surveillance. A pre-malignant cervical carcinoma in situ was also reported. The incidence of malignancies during the study did not exceed the expected rate in a population standardized for country, gender and age. Conclusion: The safety and tolerability profile observed in the CLARITY study together with the reported efficacy support the potential for cladribine tablets as an MS therapy.


Expert Opinion on Drug Safety | 2015

Dimethyl fumarate for treating relapsing multiple sclerosis

William A. Sheremata; Andrew D Brown; K Rammohan

Introduction: Outcomes of two large double-blind placebo-controlled studies of oral dimethyl fumarate (DMF) in multiple sclerosis (MS) provided the basis for its marketing approval as Tecfidera® by the US FDA in early 2013 and the European Medicines Agency in February 2014. The safety of DMF is complemented by experience in the use of an oral mixture of fumaric acid esters, including DMF for psoriasis (Fumaderm®; DMF and monoethyl fumarate [DMF-MEF]) licensed in Germany in 1994. Areas covered: This article reviews the pivotal trials leading to the approval of DMF for MS and the pharmacological literature related to the extensive use of oral fumaric acid esters for psoriasis over the last quarter century. Anecdotal reports of serious adverse reactions to DMF-MEF are also reviewed in this report. Expert opinion: DMF is generally safe and well tolerated. Flushing and gastrointestinal side effects are relatively common for the approved DMF dose but are ordinarily mild and self-limited. No increase in malignancies has been reported despite theoretical concerns. Although progressive multifocal encephalopathy has been reported anecdotally in 5 of > 196,000 patient-years of experience with fumaric acid esters, none of the 65,000 DMF MS patients treated in the first year has been affected. Appendix to the abstract: Subsequent to the acceptance of this article for publication, the manufacturer has notified physicians of the death of one patient from PML complicating use of DMF in the DEFINE study extension (ENDORSE). This does not alter the expert opinion rendered regarding the safety of DMF. We await the outcomes and recommendations from the ongoing investigation into this case.


Multiple Sclerosis Journal | 2016

Impaired retinal microcirculation in multiple sclerosis

Hong Jiang; Silvia Delgado; Jia Tan; C.–Y. Liu; K Rammohan; Delia Cabrera DeBuc; Byron L. Lam; William J. Feuer; Jianhua Wang

Background: The transparent ocular structure enables quantitative analysis of microvasculature of retina, a neuronal tissue affected by multiple sclerosis (MS). Objective: The aim of this study was to determine whether the retinal blood flow velocity and flow volume at the macula are impaired in patients with relapsing remitting multiple sclerosis (RRMS). Methods: A total of 17 RRMS patients and 17 age- and gender-matched healthy subjects were assessed. A retinal function imager was used to measure the blood flow velocity of retinal arterioles and venules and to calculate the total perifoveal blood flow volume. Results: The blood flow velocities of the retinal arterioles (3.34 ± 0.89 mm/s) and venules (2.61 ± 0.6 mm/s) were significantly lower in MS patients than normal subjects (arteriole: 4.10 ± 0.87 mm/s; venule: 3.22 ± 0.65 mm/s, both p = 0.01). In addition, the total perifoveal blood flow volume in arterioles (3.74 ± 1.64 nL/s) and venules (3.81 ± 1.60 nL/s) were significantly lower in MS patients than in normal subjects (arteriole: 4.87 ± 1.41 nL/s, p = 0.02; venule: 4.71 ± 1.64 nL/s, p = 0.04). Conclusion: The impaired retinal microcirculation in RRMS patients indicates microvascular dysfunction in MS.


Journal of NeuroVirology | 2014

CNS demyelinating disorder with mixed features of neuromyelitis optica and multiple sclerosis in HIV-1 infection. Case report and literature review

Silvia Delgado; Janice Maldonado; K Rammohan

An African-American male presented with bilateral visual impairment, gait difficulties, and bladder and bowel incontinence raising concerns for multiple sclerosis (MS) or neuromyelitis optica (NMO). He was identified to be HIV-1 infected with high viral load and low CD4+ counts. Magnetic resonance imaging (MRI) of the brain was abnormal, but atypical for MS. MRI of the cervical and thoracic spinal cord showed multiple areas of myelitis with a longitudinally extensive thoracic transverse myelitis that showed enhancement with gadolinium suggestive of NMO. Cerebrospinal fluid showed oligoclonal IgG bands but did not show reactivity to aquaporin 4. Patient underwent treatment for the acute exacerbation with intravenous corticosteroids and treatment of the HIV infection with highly active antiretroviral therapy (HAART). A year later, his viral load was <20 copies/ml and CD4+ counts were normal. Vision did not significantly improve, but his ambulation improved from a near total non-ambulatory state to ambulating without aids and resolution of the bladder and bowel incontinence. A demyelinating disorder of the central nervous system (CNS) like MS or NMO has been previously reported in the context of HIV infection. The remarkable improvement of symptoms has also been previously reported with HAART, and these observations have led to clinical trials of MS with HAART therapy in the absence of HIV infection. We reviewed the few cases of CNS demyelinating disorders with HIV infection reported in the literature and speculate on the mechanisms of pathogenesis.


Ophthalmology | 2016

In Vivo Characterization of Retinal Microvascular Network in Multiple Sclerosis.

Hong Jiang; Silvia Delgado; C.–Y. Liu; K Rammohan; Delia Cabrera DeBuc; Byron L. Lam; Jianhua Wang

Multiple sclerosis (MS) is an inflammatory demyelinating disorder of the central nervous system characterized by progressive neurodegeneration. Current management aims to reduce the inflammation through immunomodulation. However, the effectiveness of these treatments for preventing degeneration is unclear. Vascular alterations, which may be caused by inflammatory cerebral endotheliopathy, could play a role in neurodegeneration. Indeed, increased incidence of ischemic stroke and diffuse hypoperfusion in normal-appearing white and gray matter have been reported in MS patients. Thus, studying cerebral microvascular changes may reveal the underlying pathophysiology that connects inflammation and neurodegeneration. Because the retina is an extension of the brain, the cerebral and retinal vasculature shares similar anatomic


Expert Review of Neurotherapeutics | 2016

Fingolimod: a review of its mode of action in the context of its efficacy and safety profile in relapsing forms of multiple sclerosis

K Rammohan; Kathleen Hawker; Edward Fox

Fingolimod is an orally administered, first-in-class therapy for the treatment of relapsing forms of multiple sclerosis. Data from pivotal clinical trials show that fingolimod has a robust, significant effect on annualized relapse rates and MRI outcomes. Fingolimod has a novel, well-characterized mechanism of action. It acts through a specific set of receptors, sphingosine 1-phosphate receptors, present on the surface of a wide range of human cells and tissues, including neural cells, neurons and lymphocytes. Here we review the current literature to describe the mechanism of action of fingolimod in the context of its well-established clinical efficacy and safety profile. Understanding of the mechanisms behind any non-therapeutic effects of fingolimod facilitates their prediction and management in the clinical setting.


Neuroepidemiology | 2015

Clinical Expression of Multiple Sclerosis in Hispanic Whites of Primarily Caribbean Ancestry

Athena Hadjixenofontos; Ashley Beecham; Clara P. Manrique; Margaret A. Pericak-Vance; Leticia Tornes; Melissa Ortega; K Rammohan; Jacob L. McCauley; Sylvia R. Delgado

Objective: The clinical characteristics of multiple sclerosis (MS) are not well defined in Hispanic populations. We hypothesized that disease presentation in Hispanic white (HW) patients will be different from non-Hispanic white (NHW) patients given their ancestral background and reported lower disease prevalence. This study was undertaken to compare HW of primarily Caribbean ancestry to NHW on clinical characteristics of MS. Methods: We assessed 312 HW and 312 NHW patients with definite MS for clinical disease characteristics obtained through consented review of medical records. In order to assess the relationship between age-related phenotypes and ethnicity, linear regression was used. Logistic regression was used to assess the relationship between ethnicity and descriptors of disease presentation and severity as well as presence of neurological symptoms. Results: We observed a significantly younger age at diagnosis (p = 1.38E-02) and age at exam (p = 2.36E-05) in HW. However, age at first symptom did not differ significantly between the two groups. Furthermore, within HW, the mean age at first symptom and age at diagnosis was significantly younger in those born in the United States (p < 1.00E-03 for both). Interestingly, we noted an increase in ambulatory disability in HW patients, primarily among those with relapsing disease (p = 4.18E-03). Conclusions: We found several differences in age-related phenotypes and disease severity between HW of primarily Caribbean origin and NHW patients. To our knowledge, this is the largest study to date that examined the clinical characteristics of MS in Hispanic patients of largely Caribbean origin.

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Gavin Giovannoni

Queen Mary University of London

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Giancarlo Comi

Vita-Salute San Raffaele University

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Peter Rieckmann

University of Erlangen-Nuremberg

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