Objectives: The aim of the study was to determine the prevalence of potential clinically significant drug interactions (CSDIs) in HIV‐positive individuals and to identify associated risk factors.Methods: A cross‐sectional study was conducted including all HIV‐infected out‐patients attending the Pharmacy Service of a regional reference hospital in Murcia, south‐eastern Spain. The complete treatment was screened for possible CSDIs using the Spanish College of Pharmacists' online software resource, bot. Additionally, the severity level of the CSDIs involving antiretroviral (ARV) drugs was compared with that established in the specific antiretroviral database InteraccionesHIV.com. Multivariate logistic regression was used to identify associated risk factors.Results: Two hundred and sixty‐eight patients were included in the study. A total of 292 potential drug interactions were identified, of which 102 (34.9%) were CSDIs, of which 52.9% involved ARV drugs. Seven therapeutic drug classes were involved in 75% of CSDIs (protease inhibitors, benzodiazepines, nonsteroidal anti‐inflammatory drugs, nonnucleoside reverse transcriptase inhibitors, corticosteroids, antithrombotics and proton pump inhibitors). Factors independently associated with CSDIs were treatment with more than five drugs [odds ratio (OR) 15.1; 95% confidence interval (CI) 6.3–36.2], and treatment with a protease inhibitor (OR 5.3; 95% CI 2.4–11.74).Conclusions: The findings of this study suggest that the prevalence of clinically relevant drug−drug interactions is high in HIV‐infected patients, and could represent a major health problem. Awareness, recognition and management of drug interactions are important in optimizing the pharmaceutical care of HIV‐infected patients and helping to prevent adverse events and/or loss of efficacy of the drugs administered.

Introduction: numerous studies have shown a positive correlation between serum biologic drug concentrations and favorable therapeutic outcomes during the induction and maintenance period in patients with Crohn's disease (CD). To our knowledge, only a few and contradictory studies have determined the association between ustekinumab (UST) trough concentrations and biological outcomes. This study aimed to investigate the relationship between ustekinumab trough concentrations and biological outcomes in a real-world setting. Methods: a cross-sectional cohort study was performed. All adult patients with CD who received maintenance therapy (>= 24 weeks) with ustekinumab were included in the study. Clinical response was determined using the Harvey-Bradshaw Index. Biochemical remission was defined as a fecal calprotectin level < 150 mu g/g in feces and a biochemical response as > 50 % reduction of fecal calprotectin. Results: a total of 58 CD patients were included in the study and the median UST trough concentration was 1.78 mu g/ ml (IQR: 2.56). Differences in ustekinumab trough concentrations were observed for clinical (2.25 mu g/ml vs 0.65 mu g/ ml; p = 0.006) and biochemical remission (2.33 mu g/ml vs 1.03 mu g/ml; p = 0.047). According to ROC analysis, a cut-off of 1.4 lag/ml (AUC: 077) and 2.0 lag/ml (AUC: 0.65) were identified for predicting clinical and biochemical remission, respectively. Likewise, ustekinumab trough levels were also higher in "composite clinical/biochemical remission" (2.38 lag/ml vs 1.08 mu g/ml; p = 0.042). The trough level that was best associated with composite clinical/biochemical remission was 2.2 lag/ml (AUC: 0.69). Conclusion: this real-life study shows the association between ustekinumab trough concentration and clinical and biochemical remission and we suggest an optimal cutoff point higher than 2.2 lag/ml. Further studies are needed to confirm the findings and to identify the optimal cut-off in different disease outcomes and disease phenotypes.

Introduction: Therapeutic drug monitoring (TDM) in inflammatory rheumatic diseases (RMDs) is gaining interest. However, there are unresolved questions about the best practices for implementing TDM effectively in clinical settings. Objective: The primary objective of this study was to evaluate whether early TDM of adalimumab predicts drug survival at 52 weeks in patients with RMDs. The secondary objective was to identify factors associated with pharmacokinetic failure and treatment discontinuation. Methods: A retrospective cohort study included patients aged ≥ 18 years with RMDs who initiated adalimumab therapy. Early TDM was performed within the first 26 weeks, and adalimumab trough levels (ATL) and anti-drug antibodies were measured. Drug survival was assessed at 52 weeks and defined as the time from adalimumab initiation to discontinuation for any reason. Multivariate analyses were conducted to identify factors influencing outcomes. Results: The study included 194 patients, of whom 56.7% exhibited ATL below the therapeutic range during the first 26 weeks. In the multivariate analysis, subtherapeutic concentrations were significantly associated with higher weight (OR = 1.02; p = 0.040) and ankylosing spondylitis diagnosis (OR = 3.68; p < 0.001). At 52 weeks, 43.8% of patients had discontinued adalimumab. Low ATL (< 1 µg/mL) was strongly associated with treatment discontinuation (OR = 7.31; p < 0.001), while concomitant methotrexate reduced this risk (OR = 0.46; p = 0.026). Conclusions: Early TDM of adalimumab predicts drug persistence and underscores its clinical relevance as a proactive tool to guide personalized treatment and reduce the risk of treatment failure. These findings highlight the importance of incorporating TDM into routine practice to optimize therapeutic outcomes. Key Points• Early TDM of adalimumab in rheumatic diseases shows that low drug exposure predicts reduced drug survival at 52 weeks.• Approximately half of the patients exhibit low adalimumab exposure with the standard dose (40 mg every other week).• Body weight and methotrexate use significantly impact adalimumab levels.• Immunogenicity, found in 14.4% of patients with low ADL levels, underscores the need for early ADA detection to prevent non-response and discontinuation.

This study purposes to determine the prevalence of potential and clinical relevant Drug-Drug-Interactions (pDDIs) in institutionalized older adults and to identify the pertinent factors associated. We conduct an observational, multicenter and cross-sectional study during the last quarter of 2010. We selected a sample of 275 subjects (aged ≥ 65 years) from 10 nursing homes of Murcia (Spain) by a two-stage complex sampling. pDDIs were identified using the College of Pharmacists Database. We only considered pDDIs of clinical relevance, and thereafter the relevant factors were identified through uni-level and multi-level regression analyses. A total of 210 pDDIs were identified, 120 of which were considered clinically relevant (57.1%), affecting a total of 70 elderly (25.8%). Eight pharmacological groups made up 70.2% of the clinically relevant pDDIs. More clinically relevant DDIs were found in people suffering several pathologies (OR = 2.3; 95%CI = 1.4-4.5), and also in people who take ten or more drugs daily (OR = 9.6; 95%CI = 4.8-19.1), and people who take anti-inflammatory drugs (OR = 3.9; 95%CI = 1.4-10.4). This study reveals that clinically relevant pDDIs are very common in institutionalized elderly people, and that caregivers should aim at improving their practice in order to reduce the prevalence of this phenomenon.