Kalincik, TomasSpelman, TimothyTrojano, MariaDuquette, PierreIzquierdo, GuillermoGrammond, PierreLugaresi, AlessandraHupperts, RaymondCristiano, EdgardoVan Pesch, VincentGrand'Maison, FrancoisLa Spitaleri, DanieleRio, Maria EditeFlechter, SholmoOreja-Guevara, CeliaGiuliani, GiorgioSavino, AldoAmato, Maria PiaPetersen, ThorFernandez-Bolanos, RicardoBergamaschi, RobertoIuliano, GerardoBoz, CavitLechner-Scott, JeannetteDeri, NormaGray, OrlaVerheul, FreekFiol, MarcelaBarnett, Michaelvan Munster, ErikSantiago, VetereMoore, FraserSlee, MarkSaladino, Maria LauraAlroughani, RaedShaw, CameronKasa, KrisztianPetkovska-Boskova, Tatjanaden Braber-Moerland, LeontienChapman, JoabSkromne, EliHerbert, JosephPoehlau, DieterNeedham, MerrileeBacile Bacile, Elizabeth AlejandraArruda, Walter OleschkoPaine, MarkSinghal, BhimVucic, SteveCabrera-Gomez, Jose AntonioButzkueven, Helmut2018-08-282018-08-282013-05-21Kalincik T, Spelman T, Trojano M, Duquette P, Izquierdo G, Grammond P, et al. Persistence on therapy and propensity matched outcome comparison of two subcutaneous interferon beta 1a dosages for multiple sclerosis. PLoS ONE. 2013; 8(5):e63480http://hdl.handle.net/10668/2930Clinical Trial; Comparative Study; Journal Article; Research Support, Non-U.S. Gov't;OBJECTIVES To compare treatment persistence between two dosages of interferon β-1a in a large observational multiple sclerosis registry and assess disease outcomes of first line MS treatment at these dosages using propensity scoring to adjust for baseline imbalance in disease characteristics. METHODS Treatment discontinuations were evaluated in all patients within the MSBase registry who commenced interferon β-1a SC thrice weekly (n = 4678). Furthermore, we assessed 2-year clinical outcomes in 1220 patients treated with interferon β-1a in either dosage (22 µg or 44 µg) as their first disease modifying agent, matched on propensity score calculated from pre-treatment demographic and clinical variables. A subgroup analysis was performed on 456 matched patients who also had baseline MRI variables recorded. RESULTS Overall, 4054 treatment discontinuations were recorded in 3059 patients. The patients receiving the lower interferon dosage were more likely to discontinue treatment than those with the higher dosage (25% vs. 20% annual probability of discontinuation, respectively). This was seen in discontinuations with reasons recorded as "lack of efficacy" (3.3% vs. 1.7%), "scheduled stop" (2.2% vs. 1.3%) or without the reason recorded (16.7% vs. 13.3% annual discontinuation rate, 22 µg vs. 44 µg dosage, respectively). Propensity score was determined by treating centre and disability (score without MRI parameters) or centre, sex and number of contrast-enhancing lesions (score including MRI parameters). No differences in clinical outcomes at two years (relapse rate, time relapse-free and disability) were observed between the matched patients treated with either of the interferon dosages. CONCLUSIONS Treatment discontinuations were more common in interferon β-1a 22 µg SC thrice weekly. However, 2-year clinical outcomes did not differ between patients receiving the different dosages, thus replicating in a registry dataset derived from "real-world" database the results of the pivotal randomised trial. Propensity score matching effectively minimised baseline covariate imbalance between two directly compared sub-populations from a large observational registry.enInterferón betaRelación dosis-respuesta a drogaInyecciones subcutáneasFunciones de verosimilitudEsclerosis múltipleEspectroscopía de resonancia magnéticaReproducibilidad de los resultadosResultado del tratamientoPrivación del tratamientoAdultoEsclerosis múltipleCumplimiento y adherencia al tratamientoMedical Subject Headings::Disciplines and Occupations::Social Sciences::DemographyMedical Subject Headings::Phenomena and Processes::Physiological Phenomena::Pharmacological Phenomena::Dose-Response Relationship, DrugMedical Subject Headings::Analytical, Diagnostic and Therapeutic Techniques and Equipment::Therapeutics::Drug Therapy::Drug Administration ScheduleMedical Subject Headings::Check Tags::FemaleMedical Subject Headings::Organisms::Eukaryota::Animals::Chordata::Vertebrates::Mammals::Primates::Haplorhini::Catarrhini::Hominidae::HumansMedical Subject Headings::Analytical, Diagnostic and Therapeutic Techniques and Equipment::Therapeutics::Drug Therapy::Drug Administration Routes::Injections::Injections, SubcutaneousMedical Subject Headings::Chemicals and Drugs::Amino Acids, Peptides, and Proteins::Peptides::Intercellular Signaling Peptides and Proteins::Cytokines::Interferons::Interferon Type I::Interferon-betaMedical Subject Headings::Analytical, Diagnostic and Therapeutic Techniques and Equipment::Investigative Techniques::Epidemiologic Methods::Statistics as Topic::Survival Analysis::Kaplan-Meier EstimateMedical Subject Headings::Analytical, Diagnostic and Therapeutic Techniques and Equipment::Investigative Techniques::Epidemiologic Methods::Statistics as Topic::Models, Statistical::Likelihood FunctionsMedical Subject Headings::Analytical, Diagnostic and Therapeutic Techniques and Equipment::Diagnosis::Diagnostic Techniques and Procedures::Diagnostic Imaging::Magnetic Resonance ImagingMedical Subject Headings::Check Tags::MaleMedical Subject Headings::Psychiatry and Psychology::Behavior and Behavior Mechanisms::Behavior::Health Behavior::Patient Compliance::Medication AdherenceMedical Subject Headings::Diseases::Nervous System Diseases::Autoimmune Diseases of the Nervous System::Demyelinating Autoimmune Diseases, CNS::Multiple SclerosisMedical Subject Headings::Analytical, Diagnostic and Therapeutic Techniques and Equipment::Investigative Techniques::Epidemiologic Methods::Statistics as Topic::Probability::Propensity ScoreMedical Subject Headings::Analytical, Diagnostic and Therapeutic Techniques and Equipment::Investigative Techniques::Epidemiologic Methods::Epidemiologic Research Design::Reproducibility of ResultsMedical Subject Headings::Analytical, Diagnostic and Therapeutic Techniques and Equipment::Diagnosis::Prognosis::Treatment OutcomeMedical Subject Headings::Analytical, Diagnostic and Therapeutic Techniques and Equipment::Therapeutics::Patient Care::Withholding TreatmentMedical Subject Headings::Named Groups::Persons::Age Groups::Adultresearch article23704913open access10.1371/journal.pone.00634801932-6203PMC3660604