RT Journal Article SR Electronic T1 CPC-091 Natalizumab in Cypriot Patients with Relapsing Remitting Multiple Sclerosis: Three Year Data on Safety, Efficacy and Frequency of Anti-JC Virus Antibodies JF European Journal of Hospital Pharmacy: Science and Practice JO Eur J Hosp Pharm FD British Medical Journal Publishing Group SP A197 OP A198 DO 10.1136/ejhpharm-2013-000276.548 VO 20 IS Suppl 1 A1 Kkolou, E A1 Gaglia, E A1 Toufexis, J A1 Pantzaris, M YR 2013 UL http://ejhp.bmj.com/content/20/Suppl_1/A197.3.abstract AB Background Natalizumab (NAT) is a recombinant humanised anti-α4-integrin antibody used in treating Relapsing Remitting (RR) Multiple Sclerosis (MS). Purpose To evaluate the long-term safety and efficacy of NAT in Cypriot patients, to assess the frequency of anti-JC Virus (JCV) antibodies and implement a strategy for the prevention of PML. Materials and Methods Twenty-two patients were studied prospectively for 3 years. The patients received 300 mg of NAT intravenously every 4 weeks. MRI examinations were performed at study entry and 12–24 months after the start of treatment. JCV antibody testing was performed after two years of treatment. Results Six patients (27.3%) discontinued the study due to: Severe allergic reaction (9%), generalised atony, fatigue and weakness (4%), recurring herpes infection (4%), family planning (4%) and presence of anti-JCV antibodies (anti-JCV positive) due to previous immunosuppressive therapy (4%). Most frequently reported side effects were: cardiovascular (41%), general (41%), laboratory abnormalities (41%), gastrointestinal (23%), neurological (18%), allergic reactions (18%) and depression (14%). After three years of NAT treatment, a 55.2% decrease from the baseline mean annual relapse rate was observed, as well as improvement of 0.3 points on the mean Expanded Disability Status Scale (EDSS) Score. 87.5% of the patients completing the study had repeat MRI scans. Of those, 85.7% were found to have no new or gadolinium-enhancing lesions. JC Virus antibody testing was performed after two years of NAT. Of the thirteen samples, eight (61.5%) tested positive. Two of those (25%) discontinued NAT due to previous IV mitoxantrone treatment. The remaining patients continued treatment under close supervision by the attending neurologist. No cases of Progressive Multifocal Leukoencephalopathy were reported. Conclusions Long-term therapy with natalizumab proved to be safe and effective in our population. Strict follow-up criteria were implemented for JCV antibody-positive patients remaining on treatment with natalizumab for more than two years. No conflict of interest.