Evaluating Ceftolozane/Tazobactam in Immunocompromised Patients with Pseudomonas Infections

Segment Description: Elizabeth Hirsch, PharmD, assistant professor at the University of Minnesota; and Delaney Hart, PharmD, PGY-1 pharmacy practice resident at Abbott Northwestern Hospital, discuss their poster at IDWeek 2019.

Interview transcript (modified slightly for readability):

Elizabeth Hirsch, PharmD: We looked at immunocompromised patients treated with ceftolozane/tazobactam and we think that this is an important population to study because typically phase 3 clinical trials do not include patients who are severely ill or immunocompromised. We specifically looked at patients with multidrug-resistant Pseudomonas infections and focused in on an immunocompromised patient population because those patients are typically excluded.

Delaney Hart, PharmD: This was a retrospective cohort study of patients from 15 United States institutions. The patients were defined as immunocompromised based on either their disease state or if they were taking immunosuppressive agents.

In this study our primary goal was to look at the clinical outcomes of patients using ceftolozane/tazobactam specifically with MDR Pseudomonas infections. We evaluated specifically their clinical cure rate, which was defined as no escalation in therapy or discontinuation of therapy. We also evaluated 30-day all-cause mortality in these patients, specifically in immunocompromised patients.

The outcomes that we showed were a 69% rate of clinical cure and a 19% rate of 30-day all-cause mortality. Then, we those data points and we split it based on the patient's APACHE score. So with an APACHE score greater than 25, which would indicate a more acutely ill population, we also broke it down and found that when patients had an APACHE score greater than 25 they did have a higher rate of 30-day all-cause mortality.

Elizabeth Hirsch, PharmD: So based on the findings from our study we believe that ceftolozane/tazobactam is a good treatment choice for patients that are immunocompromised and infected with multidrug-resistant Pseudomonas infections. Our clinical success rates and the 30-day all-cause mortality rates were similar to other populations of patients where similar outcomes have been studied.

The poster, Ceftolozane-Tazobactam (C/T) Treatment Outcomes in Immunocompromised (IC) Patients with Multidrug-Resistant (MDR) Pseudomonas aeruginosa (PA) Infections, was presented at IDWeek 2019 in Washington DC.