Stability Studies of Antipseudomonal Beta Lactam Agents for Outpatient Therapy

Abstract

Pseudomonas aeruginosa; Beta lactams; Multidrug-resistant bacteria

Pseudomonas aeruginosa; Betalactámicos; Bacterias resistentes a múltiples medicamentos

Pseudomonas aeruginosa; Betalactàms; Bacteris resistents a múltiples medicaments

Outpatient parenteral antimicrobial therapy (OPAT) is a useful treatment strategy against Pseudomonas aeruginosa and other multidrug-resistant bacteria. However, it is hindered by the lack of stability data for the administration of antibiotics under OPAT conditions. Our objective was to investigate the stability of nine antipseudomonal and broad-spectrum beta lactam antibiotics (aztreonam, cefepime, cefiderocol, ceftazidime, ceftazidime/avibactam, ceftolozane/tazobactam, meropenem, meropenem/vaborbactam, and piperacillin/tazobactam) to allow the spread of OPAT programs. All the antibiotics were diluted in 500 mL 0.9% sodium chloride and stored at 4, 25, 32, and 37 °C for 72 h in two different devices (infusion bags and elastomeric pumps). The solutions were considered stable if the color, clearness, and pH remained unchanged and if the percentage of intact drug was ≥90%. All the antimicrobials remained stable 72 h under refrigerated conditions and at least 30 h at 25 °C. At 32 °C, all the antibiotics except for meropenem and meropenem/vaborbactam remained stable for 24 h or more. At 37 °C, only aztreonam, piperacillin/tazobactam, cefepime, cefiderocol, and ceftolozane/tazobactam were stable for at least 24 h. The stability results were the same in the two devices tested. All the antibiotics studied are actual alternatives for the treatment of antipseudomonal or multidrug-resistant infections in OPAT programs, although the temperature of the devices is crucial to ensure antibiotic stability.

This work was supported by the Sociedad Española de Farmacia Hospitalaria and the AFinf Working Group for the project “Stability study of antimicrobials under conditions analogous to the outpatient parenteral antibiotic therapy program (OPAT)”. A.G.-V. and L.H.-H. were supported by the Instituto de Salud Carlos III, co-financed by the European Development Regional Fund (“A way to 251 achieve Europe”). A.G.-V. received financial support from the Subprograma Miguel Servet (CP19/00159). L.H.-H. received financial support from the Subprograma Juan Rodés (JR22/00049).