Changes in Hematologic Lab Measures Observed in Patients with Paroxysmal Nocturnal Hemoglobinuria Treated with C5 Inhibitors, Ravulizumab and Eculizumab: Real-World Evidence from a US Based EMR Network.

Paroxysmal nocturnal hemoglobinuria (PNH), a rare acquired hematologic disorder, can be treated with C5 inhibitors (C5i) such as eculizumab or ravulizumab. This retrospective study is the first to describe real-world treatment patterns and changes in hematologic PNH-monitoring laboratory tests among C5i-treated US patients. Data were extracted from TriNetX Dataworks Network and included patients with a PNH diagnosis between 1 January 2010, and 20 August 2021. Patients were stratified into three cohorts based on their C5i usage: eculizumab, ravulizumab (prior eculizumab), and ravulizumab (eculizumab naïve). Hematological markers (hemoglobin [Hb], lactate dehydrogenase [LDH], and absolute reticulocyte count [ARC]) and relevant clinical events (e.g., breakthrough hemolysis [BTH], complement-amplifying conditions [CAC], thrombosis, infection, and all-cause mortality) were captured any time within 12 months post-index treatment. Of the 143 (eculizumab), 43 (ravulizumab, prior eculizumab), and 33 (ravulizumab, eculizumab naïve) patients, mean age across cohorts was 42-51 years, 55-61% were female, 63-73% were White, and 33-40% had aplastic anemia. Among all cohorts 12 months post-C5i treatment, 50-82% remained anemic, 8-32% required ≥1 transfusion, and 13-59% had BTH, of which 33%-54% had CACs. Additionally, thrombosis was seen in 7-15% of patients, infection in 20-25%, and mortality in 1-7%. These findings suggest many C5i-treated patients experience suboptimal disease control.

Prevalence of Potential Drug-drug Interactions With Ritonavir-containing COVID-19 Therapy in the United States: An Analysis of the National Health and Nutrition Examination Survey.

PURPOSE: The evolving epidemiology and treatment landscape of COVID-19 necessitates research into potential drug-drug interactions (pDDIs) from the use of new treatments for COVID-19, particularly those that contain ritonavir, a potent inhibitor of the cytochrome P350 3A4 (CYP3A4) metabolic pathway. In this study, we assessed the prevalence of pDDIs between medications for chronic conditions metabolized through the CYP3A4 metabolic pathway and ritonavir-containing COVID-19 medications in the US general population. METHODS: This study combined National Health and Nutrition Examination Survey (NHANES) waves 2015 to 2016 and 2017 to March 2020 to observe pDDI prevalence between ritonavir-containing therapy and coadministered medications among US adults 18 years or older. CYP3A4-mediated medications were identified from affirmative medication questionnaire response and associated prescription examination by surveyors. CYP3A4-mediated medications with associated pDDIs with ritonavir and assessed pDDI severity (minor, major, moderate, and severe) were obtained from the University of Liverpool's COVID-19 online drug interaction checker, Lexicomp, and US Food and Drug Administration fact sheets. pDDI prevalence and severity were evaluated by demographic characteristics and COVID-19 risk factors. FINDINGS: A total of 15,685 adult participants were identified during the 2015 to 2020 NHANES waves. Survey participants used a mean (SD) of 2.7 (1.8) drugs with likelihood of a pDDI. The weighted prevalence of major to contraindicated pDDIs among the US population was 29.3%. Prevalence rates among those 60 years and older, with serious heart conditions, with moderate chronic kidney disease (CKD), with severe CKD, with diabetes, and with HIV were 60.2%, 80.7%, 73.9%, 69.5%, 63.4%, and 68.5%, respectively. Results remained largely unchanged after removal of statins from the list of drugs associated with ritonavir-based pDDIs. IMPLICATIONS: Approximately one-third of the US population would be at risk for a major or contraindicated pDDI should they receive a ritonavir-containing regimen, and this risk increases significantly among individuals 60 years or older and with comorbidities such as serious heart conditions, CKD, diabetes, and HIV. The state of polypharmacy in the US population and the quickly changing COVID-19 landscape indicate significant risk of pDDIs among those requiring treatment with ritonavir-containing COVID-19 medications. Practitioners should take polypharmacy, age, and comorbidity profile into account when prescribing COVID-19 therapies. Alternative treatment regimens should be considered, especially for those of older age and those with risk factors for progression to severe COVID-19.

Adverse Events and Healthcare Utilization Associated With Outpatient Parenteral Antimicrobial Therapy Among Older Versus Younger Adults.

Among older (n = 204) versus younger (n = 253) adults, there was no difference in adverse events (adjusted odds ratio [aOR] = 0.98; 95% confidence interval [CI] = 0.6-1.6) or healthcare utilization (incidence rate ratio = 1.09; 95% CI = 0.9-1.3) within 30 days after discontinuing outpatient parenteral antimicrobial therapy. Vancomycin (aOR = 1.92) and oxacillin (aOR = 3.12) were independently associated with adverse events.