Ana Pena PhD,  —

Ana is a molecular biologist with a passion for communication and discovery. As a science writer, her goal is to provide readers, in particular patients and healthcare providers, with clear and quality information about the latest medical advances. Ana holds a Ph.D. in Biomedical Sciences from the University of Lisbon, Portugal, where she specialized in infectious diseases, epigenetics, and gene expression.

Articles by Ana Pena

Truly ‘Benign MS’ Evident in Only Small Minority of Patients, Large UK Study Reports

Multiple sclerosis (MS) that appears to be "genuinely benign" 15 years after diagnosis is evident in a small number of patients, a large population-based study from the U.K. reports. But, its researchers note, the term “benign” is often not clinically accurate as used, because it is based largely on perceptions of disease impact. The study “How common is truly benign MS in a UK population?” was published in the Journal of Neurology, Neurosurgery & Psychiatry. The concept of benign MS is controversial, especially among clinicians. Still, long-term epidemiological studies have consistently identified a small fraction of patients whose MS progresses very slowly over a long span of years. Determining the prevalence of this type of MS in the population has been difficult, as estimates can vary significantly depending of the definition of “benign” that is adopted. Researchers sought to determine an accurate estimate of benign MS in the U.K. population, using a rigorous and comprehensive clinical definition of a truly benign disease. This definition included minimal physical disability (EDSS score of less than 3), and no significant fatigue, mood disturbance, cognitive impairment or interrupted employment in the absence of treatment with disease-modifying therapies over 15 years or more years after symptom onset. They screened an U.K. population-based registry containing data on 3,062 MS patients to identify those with "unlimited walking ability" 15 or more years after diagnosis. A representative sample of 60 patients  from this pool was analyzed (45 women and 15 men, mean age of 57); they had a mean disease duration of 28 years. Nine out of these 60 (15%; 8 women and one men) fulfilled the study’s criteria for truly benign disease. These nine people had a mean age of 27 at symptom onset, a median EDSS disability score of 1.5 (minimal signs of disability), and a mean disease duration of 31 years. "Those nine individuals with truly benign MS all remained in a relapsing–remitting state," the study noted. "However, only two out of nine showed disease arrest within the first decade; the remainder all continued to experience relapses well into their second or third decade of MS," but the rates of such relapses were low. MS in the remaining patients was not classified as benign, mostly due to evidence of cognitive difficulties (57%), and the disease's impact on employment status (52%) with many taking early retirement. Based on these results, a population frequency for "benign MS" under the definitions used was estimated at 2.9%. But the researchers noted that a large proportion of patients (65%; 39 patients out of 60) reported their disease as benign, according to a lay definition. Their self-reported status poorly agreed with the clinical assessments done throughout the study. "There is no accepted definition to offer patients when exploring whether they feel their MS is benign; the definition we chose incorporates the fundamental principles of low impact on a person, absence of complications and a favourable outcome and is in line with definitions provided by third-party support groups," the researchers wrote. Many  considering themselves with benign disease did so based on their "perception" of their disease, the team added, and one that "appeared to be driven as much by mood, fatigue and bladder function as by physical ability."  “In conclusion, after detailed clinical assessment, a small minority of people with MS appear genuinely unaffected by symptoms after 15 years,” the researchers added. They also called attention to the fact that EDSS-based definitions of benign MS and the inconsistency between patient and clinician perception of benign MS compromise the use of the term ‘benign’ in clinical practice. They also emphasize that studying individuals with benign MS “has the potential to uncover clues to mechanisms underlying favorable outcomes in MS, provide insights into new therapeutic targets and have implications for patient counselling, individual patient management and the construct of clinical trials.”

Shorter Washout Period Lessens Relapse Risk When Switching from Tysabri to Gilenya in RRMS, Study Finds

Shortening the washout period to four weeks when switching from Biogen’s Tysabri to Novartis’ Gilenya is safe and reduces the chances of experiencing a disease flare in patients with relapsing-remitting multiple sclerosis (RRMS), a small Swiss study found. A four-week washout reduced the risk of having a disease relapse or an increase in disease activity, compared with an eight-week washout period, for two years after switching from Tysabri to Gilenya. Although Tysabri effectively slows worsening of MS symptoms and the appearance of disease flares, its use is under a strict risk management plan as it heightens the risk of developing a rare and life-threatening brain infection called progressive multifocal leukoencephalopathy, also known as PML. Some patients may switch to Gilenya, an alternative disease-modifying therapy for RRMS. Gilenya has been associated with a lower risk of PML infection and seen to reduce relapses, disability worsening, and the appearance of new brain lesions on clinical trials. It also is the only therapy approved by the U.S. Food and Drug Administration for children with MS as young as 10. When switching from Tysabri to Gilenya, it is important to consider the washout period, which is the period when the patient is taken off medications. If too long, it may lead to disease reactivation, which can be even stronger than before starting Tysabri. There is little evidence about the optimal length of washout periods, but a Phase 3 trial showed that an eight-week washout between Tysabri and Gilenya was beneficial compared with longer washouts of 12 or 16 weeks. The eight-week washout enabled more RRMS patients to become free from relapses and lowered disease activity. To study if a shorter washout period of four weeks further reduced the risk of MS reactivation, researchers conducted an open-label, observational study at the University Hospital, Basel, Switzerland. The study enrolled 25 RRMS patients who were appointed to switch from Tysabri to Gilenya. Participants were assigned to either a four-week or an eight-week washout period, and were followed for two years after switching to Gilenya. Although patients were older in the four-week washout group, disease activity and disability scoreswere not significantly different between groups at the beginning of the study. Relapses, disability scores, and disease activity on magnetic resonance imaging scans were recorded at baseline and weeks 8, 12, 16, 20 32, 56, and 108. In the first year (week 56) the proportion of patients with disease flare-ups or disease activity on MRI was not significantly different between the two washout groups, affecting 55.6% and 62.5% of the patients who had a four-week and an eight-week washout, respectively. However, at the end of the two-year follow-up (week 108), recurrent event analysis showed that patients who were on the four-week washout group were 77% less likely to experience relapses. The combined risk for relapse or disease activity on MRI also was 58% lower in the four-week group, compared with those who had an eight-week washout. In addition, researchers found that patients who had flares more frequently in the year before discontinuing Tysabri also had a nearly four times higher risk of experiencing relapses in the first year after switching to Gilenya. This suggests that the number of relapses before switching from Tysabri can predict disease reactivation once on other disease-modifying therapies. Both washout periods were deemed safe, with no serious adverse side effects or cases of opportunistic infections, including PML, being reported. Researchers emphasized, however, that the findings need to be confirmed in larger studies.