Analysis of survival rate and persistence predictors of baricitinib in real-world data from a large cohort of rheumatoid arthritis patients

Objectives: The persistence in therapy of rheumatoid arthritis drugs and particularly bDMARD is a limiting factor for their long-term use. The randomized controlled trials (RCTs) may not reflect real-world contexts due to strict inclusion and exclusion criteria. Baricitinib, which targets both JAK1 and JAK2, has been used in Italy for several years. The aim of this multi-center study is to assess the real world persistence on therapy of baricitinib in RA patients and to identify predictive factors of baricitinib's survival rate. Methods: This is a retrospective, multicentric, Italian, longitudinal study. All patients were enrolled according to the following criteria: a) age ≥ 18 years old; b) diagnosed with RA according 2010 ACR/EULAR classification criteria; c) treated with baricitinib. In order to describe baricitinib clinical efficacy, the survival rate was evaluated by The Kaplan-Meier curve. Then, predictive factors of drug retention rate were assessed by performing the Cox analysis, identifying which risk factors influenced treatment persistence. Results: Overall, we included 478 patients treated with baricitinib. Among them, 380 (79.5%) were females. Baricitinib's survival rate was 94.6% at 6 months, 87.9% at 12 months, 81.7% at 24 months and 53.4% at 48 months. The Cox analysis regression showed that a higher bDMARDs/tsDMARD line of therapy seems to be a negative prognostic factor for the drug retention rate (HR 1.26 CI 95% 1.07-1.49, p = 0.006. Conclusion: Real-life study confirms baricitinib effectiveness up to 4 years, but previous treatment with bDMARDs was a negative prognostic factor for its survival rate

Influence of safety warnings on the prescribing attitude of JAK 2inhibitors for rheumatoid arthritis in Italy

The Janus kinase inhibitors (JAKi) tofacitinib (TOFA), baricitinib (BARI), upadacitinib (UPA) and 74 filgotinib (FILGO) are effective drugs for the treatment of rheumatoid arthritis. However, the US 75 Food & Administration (FDA) raised concerns on the safety of TOFA after its approval. This 76 prompted the European Medicines Agency (EMA) to issue two safety warnings for limiting TOFA 77 use then extended in a third warning to all Jaki in patients at high risk of developing serious adverse 78 events (SAE). These included thrombosis, major adverse cardiac events (MACE) and cancer. Thepurpose of this work was to analyze how the first two safety warnings from EMA affected the pre- 80 scribing of Jaki by rheumatologists in Italy. All patients with rheumatoid arthritis who had been 81 prescribed JAKi for the first time in a 36-month period from July 1, 2019, to June 30, 2022 were con- 82 sidered. Data were obtained from the medical records of 29 Italian tertiary referral rheumatology 83 centers. Patients were divided into three groups of 4 months each, depending on whether the JAKi 84 prescription had occurred before the EMA's first safety alert (July 1-October 31, 2019, Group 1), 85 between the first and second alerts (November 1, 2019-February 29, 2020, Group 2), or between the 86 second and third alerts (March 1, 2021-June 30, 2021, Group 3). Percentage and absolute changes in 87 patients prescribed the individual JAKi were analyzed. Differences among the three Groups of pa- 88 tients in demographic and clinical characteristics were also assessed. A total of 864 patients were 89 prescribed a JAKi during the entire period considered. Of these, 343 were identified in Group 1, 233 90 in Group 2 and 288 in Group 3. An absolute reduction of 32% was observed in the number of patients 91 prescribed a JAKi between Group 1 and Group 2 and 16% between Group 1 and Group 3. In contrast, 92 there was a 19% increase in the prescription of a JAKi in patients between Group 2 and Group 3. In 93 the first Group, BARI was the most prescribed drug (227 prescriptions, 66.2% of the total), followed 94 by TOFA (115, 33.5%) and UPA (1, 0.3%). In the second Group, the most prescribed JAKi was BARI 95 (147, 63.1%), followed by TOFA (65, 27.9%) and UPA (33, 11.5%). In the third Group, BARI was still 96 the most prescribed JAKi (104 prescriptions, 36.1%), followed by UPA (89, 30.9%), FILGO (89, 21.5%) 97 and TOFA (33, 11.5%). The number of patients prescribed TOFA decreased significantly between 98 Group 1 and Group 2 and between Group 2 and Group 3 (p ˂ 0.01). Patients who were prescribed 99 BARI decreased significantly between Group 1 and Group 2 and between Group 2 and Group 3 (p 100 ˂ 0.01). In contrast, patients prescribed UPA increased between Group 2 and Group 3 (p ˂ 0.01). 101 These data suggest that the warnings issued for TOFA were followed by a reduction in total JAKi 102 prescriptions. However, the more selective JAKi (UPA and FILGO) were perceived by prescribers 103 as favorable in terms of risk/benefit ratio and their use gradually increased at the expense of the 104 other molecules

Seasonal autoregressions with regime switching

Markov switching autoregressive models (MSARMs) are efficient tools to analyse non-linear and non-normal time series. A special MSARM with a hidden state-dependent seasonal component is proposed here to analyse periodic time series. We present a complete Metropolis-within-Gibbs algorithm for constraint identification, for model choice and for the estimation of the unknown parameters and the latent data. These three consecutive steps are developed tackling the problem of the hidden states labeling, by means of random permutation sampling and constrained permutation sampling. The missing observations occurring within the observed series and the future values are respectively estimated and forecasted considering them as unknown parameters. We illustrate our methodology with an example about the dynamics of an air pollutant

Direzione di massima risolvenza dell'indice di Mortara: confronto con i più consueti indici di connessione normalizzati

The concept of resolution has been recently introduced (see Zanella (1988)) as a possible criterion for comparing the most usual descriptive normalized measures of association like those of Goodman-Kruskal, Cramèr, Mortara and of the entropic type. For a given contingency table, the paper refers to the problem of the existence of directions along which Mortara's measure of association is more (not less) resolving than any of the others above mentioned (admissibility). In the first part of the paper stationary directions, for which the resolution function of Mortara's measure of association takes its maximum value, are found. The second part of the study deals with the comparison of the above mentioned measures of association along the former stationary directions and that is done from a theoretical as well as numerical point of view. The following conclusion has been reached Mortara's measure of association can be considered as being admissible in regard to the others, as far as square contingency tables are concerned