TOPLINE:

In patients with solid tumors with uncomplicated infections, short vs long courses of antibiotic therapy for uncomplicated infections showed comparable outcomes, with no significant differences in 30-day infection recurrence, additional antibiotic use, cancer treatment delays, and adverse events.

METHODOLOGY:

• Patients with cancer are at an increased risk for infection, which complicates antibiotic stewardship and underscores the need to balance efficacy with safety through optimal treatment duration.
• Researchers conducted a noninferiority study in ambulatory clinics across southeast Michigan comparing short antibiotic courses (≤ 5 days) with long courses (7-10 days) for uncomplicated infections in patients with solid tumors.
• Among 303 participants — mostly with breast or lung cancer — 92 (median age, 65 years; 69% women at birth) received short courses and 211 (median age, 65 years; 74% women at birth) received long courses of antibiotic therapy.
• All participants had initiated cancer therapy within 3 months of initial antibiotic prescription for urinary tract infection, lower respiratory tract infection, or acute bacterial skin and skin structure infection.
• The primary endpoint was a 30-day composite of probable or proven infection-related recurrence or the need for additional antibiotic therapy, and the secondary outcomes included cancer treatment delays and antibiotic-related adverse events at 30 and 90 days.

TAKEAWAY:

• Short antibiotic course therapy showed no independent association with the 30-day risk for infection recurrence or the need for additional antibiotics (adjusted odds ratio, 0.478; 95% CI, 0.152-1.501).
• The 30- and 90-day outcomes were not significantly different between the two treatment groups. Delays in cancer treatment due to infection occurred in 12% of patients in the short-course group and 15% of those in the long-course group.
• At 30 days, gastrointestinal upset was reported in one patient in the short-course group and one in the long-course group, while one patient in the long-course group reported Clostridioides difficile infection.

IN PRACTICE:

“These findings suggest safety and effectiveness of short-course therapy in select immunocompromised patients, with potential benefits including reduced resistance and adverse events, improved adherence, and fewer treatment delays,” the authors of the study wrote.

SOURCE:

The study was led by Christen J. Arena, PharmD, Department of Pharmacy, Henry Ford Hospital in Detroit. It was published online on August 21, 2025, in Open Forum Infectious Diseases.

LIMITATIONS:

The 7-day median duration of treatment in the long-course group limited the detection of harm in the treatment groups. Heterogeneity in cancer types and infections may have introduced confounding despite the use of strict criteria and multivariable modeling. Reliance on International Classification of Diseases, 10th Revision codes potentially reduced the sample size, and insufficient power prevented the establishment of noninferiority, increasing the risk for a type II error.

DISCLOSURES:

The authors reported receiving no financial support for this research and declared having no conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.