BACKGROUND: Cost savings can be achieved with the practice of tablet splitting. Previous research has shown weight nonuniformity within tablet halves. However, limited research to date has found that the potential dose inaccuracy resulting from splitting tablets does not significantly affect clinical outcomes. OBJECTIVE: To determine the drug content and weight in split half-tablets of 6 commonly split medications using drug assay analysis. METHODS: This study was performed by 2 fourth-year pharmacy students using 30 randomly selected tablets of each of the following 6 medications: warfarin sodium 5 milligrams (mg), simvastatin 80 mg, metoprolol succinate 200 mg, metoprolol tartrate 25 mg, citalopram 40 mg, and lisinopril 40 mg. A randomly selected half of the tablets were split by a single pharmacy student using a tablet cutter, and the remaining tablets were kept whole. Drug content was analyzed for 15 whole tablets and 30 half-tablets for each of the 6 drugs using high performance liquid chromatography, an analytical tool used to identify and quantify substances in solution. Drug content uniformity was assessed by comparing drug content within halftablets with one-half of the drug content mean found for all whole tablets in the sample. Weight uniformity was assessed by comparing half-tablet weights, as determined by a Mettler analytical balance, with one-half of the mean weight for whole tablets in the sample. The percentages by which each whole tablet's or half-tablet's drug content and weight differed from sample mean values were compared with proxy United States Pharmacopeia (USP) specification ranges for drug content (95%-105% for warfarin sodium and 90%-110% for the other 5 drugs). Additionally, these outcomes were compared for nonscored versus scored tablets. The percent relative standard deviation (%RSD, ratio of the standard deviation to the mean), a commonly used measure of the repeatability and precision of assays used to analyze drug content, was also calculated in order to determine whether the drugs met proxy USP specification for %RSD (less than 6% for all drugs studied). RESULTS: A total of 43 of 180 half-tablets (23.9%) differed from sample mean values by a percentage that fell outside of proxy USP specification for drug content; warfarin sodium (11 of 30 half-tablets, 36.7%), simvastatin (3 of 30 half-tablets, 10.0%) metoprolol succinate (10 of 30 half-tablets, 33.3%), metoprolol tartrate (4 of 30 half-tablets, 13.3%), citalopram (5 of 30 half-tablets, 16.7%), and lisinopril (10 of 30 half-tablets, 33.3%). Half-tablets outside of proxy USP specification for weight included warfarin sodium (10 of 30 half-tablets, 33.3%), metoprolol succinate (6 of 30 half-tablets, 20%), and lisinopril (7 of 30 half-tablets, 23.3%). The %RSDs for drug content and weight fell outside of the proxy USP specification for %RSD for metoprolol succinate (drug content = 8.98%, weight = 7.70%) and lisinopril (drug content = 10.41%, weight = 8.13%). Mean percent weight loss after splitting was less than 1% for al...

Ambrisentan is an effective and safe treatment which is, in the authors' opinion, a valuable addition to the armamentarium against PAH. Ambrisentan offers a relative lack of drug interactions, once daily dosing and reassuring liver safety, offering safety and convenience advantages over bosentan. Presently, there is a lack of comparative studies between PDE5 inhibitors and endothelin receptor antagonists and a lack of data comparing bosentan with ambrisentan. This is hindering data-based conclusions regarding relative efficacy and further studies are needed to define the role of ambrisentan in the management of PAH.

Background The data on CAPA in the U.S. are limited to date and clinical characteristics unique to this phenomenon have not been widely reported. Methods This retrospective observational study was conducted at multiple VA hospitals across southern California and Arizona. CAPA cases were identified in inpatients with laboratory-confirmed COVID-19 based on microbiologic or serologic evidence of aspergillosis and pulmonary abnormalities on imaging, and were classified according to ECMM/ISHAM consensus definitions. Characteristics of interest included immunosuppressive/modulatory agents used prior to onset of CAPA, COVID-19 disease course, length of hospitalization, and mortality. Results Seventeen patients with probable (18%) or possible (82%) CAPA were identified from April 2020 to March 2021. Values below reported as medians. All patients were male and 13 (76%) were white, with age 74 years and BMI 26 kg/m2. Baseline comorbidities included diabetes mellitus (47%), cardiovascular disease (65%), and pulmonary disease (71%). Evidence of aspergillosis was mostly based on respiratory culture, with mainly A. fumigatus (75%). Systemic corticosteroids were used in 14 patients, with a total dose of 400 mg prednisone equivalents starting 10 days prior to Aspergillus detection. Patients also received tocilizumab (18%), leflunomide (6%), tacrolimus (6%), mycophenolate (6%), and investigational agent LSALT or placebo (6%); 2 patients (12%) did not receive any immunosuppression/modulation. Length of hospitalization for COVID-19 was 22 days. Death occurred in 12 patients (71%), including all patients with probable CAPA, at 34 days after COVID-19 diagnosis and 16 days after CAPA diagnosis. Eight patients (47%) were treated for aspergillosis; mortality did not appear to differ with treatment (75% vs. 67%). Table 1. COVID-19 Inpatient Characteristics Table 2. Incidence of Aspergillus Growth on Respiratory Culture Conclusion This case series reports high mortality among patients with CAPA; the primary contributor to this outcome is unclear. Frequency of lower respiratory tract sampling in patients with COVID-19 may have limited diagnosis of CAPA. Interestingly, inpatient respiratory cultures with Aspergillus spp. increased compared to previous years. Future work will attempt to identify risk factors for CAPA and attributable mortality via comparison to inpatients with COVID-19 without CAPA. Disclosures Matthew B. Goetz, MD, Nothing to disclose Martin Hoenigl, MD, Astellas (Grant/Research Support)Gilead (Grant/Research Support)Pfizer (Grant/Research Support) Martin Hoenigl, MD, Astellas (Individual(s) Involved: Self): Grant/Research Support; F2G (Individual(s) Involved: Self): Grant/Research Support; Gilead (Individual(s) Involved: Self): Grant/Research Support; Pfiyer (Individual(s) Involved: Self): Grant/Research Support; Scýnexis (Individual(s) Involved: Self): Grant/Research Support Sanjay Mehta, MD, D(ABMM), DTM&H, MedialEarlySign (Consultant)ZibdyHealth (Employee, Medical Officer - Unpaid)

BackgroundVISN 22 is comprised of eight VA hospitals serving Southern California, Arizona, and New Mexico. The VISN 22 Antimicrobial Stewardship Workgroup formed in November 2018 with the purpose of sharing strong practices and program strategies. We compared antibiogram compilation strategies and antimicrobial susceptibilities and correlated antimicrobial susceptibilities for Pseudomonas aeruginosa and Escherichia coli with inpatient and outpatient antibiotic use.Methods2018 antibiograms were collected from each hospital. Antibiotic utilization rates (antibiotic days per 1000 patient-days present) were extracted from VA Corporate Data Warehouse data. Pearson correlation coefficients were calculated between 2018 utilization of specific agents and P. aeruginosa and E. coli susceptibilities to those agents at each facility.ResultsAntibiograms varied according to authorship (microbiology and/or infectious diseases), reporting frequency, rules regarding isolate reporting, and location and specimen specificity (Table 1). Facilities reported at least 90% susceptibility to a median of 3 antibiotics (range 1 to 5) for P. aeruginosa and 5 antibiotics (range 1 to 7) for E. coli.The strongest negative correlations between antimicrobial use and susceptibility were observed for meropenem/imipenem (-0.43) and piperacillin–tazobactam (-0.41) with P. aeruginosa and piperacillin–tazobactam (-0.23) and fluoroquinolones (-0.21) with E. coli. A moderate negative correlation was observed between outpatient fluoroquinolone prescriptions per 1000 patients and E. coli susceptibility (-0.24).ConclusionAntibiogram composition is variable across VISN 22; not all reporting is consistent with CLSI recommendations. There was a modest correlation between some categories of antimicrobial use and resistance in P. aeruginosa and E. coli. Sharing antibiogram and antibiotic utilization data are helpful in developing antimicrobial stewardship strategies especially as we examine those hospitals with lower rates of resistance and antibiotic use. Disclosures All authors: No reported disclosures.