Susan L. Limb

Comparative Risk of Anaphylactic Reactions Associated With Intravenous Iron Products

IMPORTANCE All intravenous (IV) iron products are associated with anaphylaxis, but the comparative safety of each product has not been well established. OBJECTIVE To compare the risk of anaphylaxis among marketed IV iron products. DESIGN, SETTING, AND PARTICIPANTS Retrospective new user cohort study of IV iron recipients (n = 688,183) enrolled in the US fee-for-service Medicare program from January 2003 to December 2013. Analyses involving ferumoxytol were limited to the period January 2010 to December 2013. EXPOSURES Administrations of IV iron dextran, gluconate, sucrose, or ferumoxytol as reported in outpatient Medicare claims data. MAIN OUTCOMES AND MEASURES Anaphylaxis was identified using a prespecified and validated algorithm defined with standard diagnosis and procedure codes and applied to both inpatient and outpatient Medicare claims. The absolute and relative risks of anaphylaxis were estimated, adjusting for imbalances among treatment groups. RESULTS A total of 274 anaphylaxis cases were identified at first exposure, with an additional 170 incident anaphylaxis cases identified during subsequent IV iron administrations. The risk for anaphylaxis at first exposure was 68 per 100,000 persons for iron dextran (95% CI, 57.8-78.7 per 100,000) and 24 per 100,000 persons for all nondextran IV iron products combined (iron sucrose, gluconate, and ferumoxytol) (95% CI, 20.0-29.5 per 100,000) , with an adjusted odds ratio (OR) of 2.6 (95% CI, 2.0-3.3; P < .001). At first exposure, when compared with iron sucrose, the adjusted OR of anaphylaxis for iron dextran was 3.6 (95% CI, 2.4-5.4); for iron gluconate, 2.0 (95% CI 1.2, 3.5); and for ferumoxytol, 2.2 (95% CI, 1.1-4.3). The estimated cumulative anaphylaxis risk following total iron repletion of 1000 mg administered within a 12-week period was highest with iron dextran (82 per 100,000 persons, 95% CI, 70.5- 93.1) and lowest with iron sucrose (21 per 100,000 persons, 95% CI, 15.3- 26.4). CONCLUSIONS AND RELEVANCE Among patients in the US Medicare nondialysis population with first exposure to IV iron, the risk of anaphylaxis was highest for iron dextran and lowest for iron sucrose.

Baseline asthma burden, comorbidities, and biomarkers in omalizumab-treated patients in PROSPERO

BACKGROUND Patients included in clinical trials do not necessarily reflect the real-world population. OBJECTIVE To understand the characteristics, including disease and comorbidity burden, of patients with asthma receiving omalizumab in a real-world setting. METHODS The Prospective Observational Study to Evaluate Predictors of Clinical Effectiveness in Response to Omalizumab (PROSPERO) was a US-based, multicenter, single-arm, and prospective study. Patients (≥12 years of age) with allergic asthma initiating omalizumab treatment based on physician-assessed need were included and followed for 12 months. Exacerbations, health care use, adverse events, and Asthma Control Test (ACT) scores were assessed monthly. Biomarkers (blood eosinophils, fractional exhaled nitric oxide, and periostin) were evaluated and patient-reported outcomes (Asthma Quality of Life Questionnaire for 12 Years and Older [AQLQ+12] and Work Productivity and Activity Impairment: Asthma questionnaire [WPAI:Asthma]) were completed at baseline and months 6 and 12. The Mini Rhinoconjunctivitis Quality of Life Questionnaire (MiniRQLQ) was completed at baseline and 12 months. RESULTS Most of the 806 enrollees (91.4%) were adults (mean age 47.3 years, SD 17.4), white (70.3%), and female (63.5%). Allergic comorbidity was frequently reported (84.2%), as were hypertension (35.5%) and depression (22.1%). In the 12 months before study entry, 22.1% of patients reported at least 1 asthma-related hospitalization, 60.7% reported at least 2 exacerbations, and 83.3% reported ACT scores no higher than 19 (uncontrolled asthma). Most patients had low biomarker levels based on prespecified cut-points. Baseline mean patient-reported outcome scores were 4.0 (SD 1.4) for AQLQ+12, 2.7 (SD 1.4) for MiniRQLQ, and 47.7 (SD 28.9) for WPAI:Asthma percentage of activity impairment and 33.5 (SD 28.7) for percentage of overall work impairment. CONCLUSION The population initiating omalizumab in PROSPERO reported poorly controlled asthma and a substantial disease burden. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT01922037.

Dose modification and dose intensity during treatment with pirfenidone: analysis of pooled data from three multinational phase III trials

Introduction Temporary dose modifications, such as reductions or interruptions, may allow patients to better manage adverse events (AEs) associated with pirfenidone use and continue treatment for idiopathic pulmonary fibrosis (IPF). However, the impact of such dosing adjustments on efficacy and safety is uncertain. Methods Patients randomised to receive treatment with pirfenidone 2403 mg/day or placebo in the Clinical Studies Assessing Pirfenidone in Idiopathic Pulmonary Fibrosis: Research of Efficacy and Safety Outcomes (CAPACITY (Study 004 (NCT00287716)) and Study 006 (NCT00287729))) and Assessment of Pirfenidone to Confirm Efficacy and Safety in Idiopathic Pulmonary Fibrosis (ASCEND (Study 016 (NCT01366209)) trials were included in the analysis (n=1247). Descriptive statistics and a linear mixed-effects model (slope analysis) for annual rate of decline in forced vital capacity (FVC) by dose intensity were performed. Treatment-emergent AEs (TEAEs) were summarised and grouped by dose intensity or body size. Results Dose reductions and interruptions occurred in 76.9% (95% CI 73.4% to 80.1%) and 46.5% (95% CI 42.6% to 50.6%) of patients receiving pirfenidone vs 72.0% (95% CI 68.3% to 75.4%) and 31.1% (95% CI 27.5% to 34.9%) of patients receiving placebo, respectively. Dose interruptions tended to occur during the first 6 months of treatment, whereas dose reductions exhibited more variability. Less FVC decline from baseline was observed in patients receiving pirfenidone versus placebo at >90% dose intensity (p<0.001) or ≤90% dose intensity (p=0.0191), showing treatment benefit in both subgroups of dose intensity. No meaningful relationship between weight and TEAEs was observed. Conclusion Dose interruptions, which may be required to manage TEAEs, mostly occurred during the first 6 months of treatment. Despite dose reductions and interruptions, most patients with IPF maintained relatively high dose intensity on pirfenidone, without compromising its treatment effect compared with placebo. Trial registration numbers NCT00287729, NCT00287716, NCT01366209.