Written by Peter Liu
Spoon Feed
IV-to-oral antibiotic transition can be considered for many infective endocarditis (IE) patients, but careful pathogen and patient selection are critical.
The POET trial – an ode to oral antibiotic therapy for endocarditis
Published attempts to treat endocarditis with oral antibiotics date back at least as far as 1948. Since then, numerous observational studies and 3 RCTs have supported a role for oral antibiotics for IE. The POET trial is the largest of these RCTs, and the only RCT published in this millennium.
This multicenter, noninferiority trial evaluated whether transitioning stable patients with left-sided infective endocarditis from intravenous (IV) to oral antibiotics was as effective as continued IV therapy. Among 400 patients, the primary composite outcome (mortality, unplanned surgery, embolic events, or bacteremia relapse) occurred in 12.1% of IV-treated patients vs. 9.0% of oral-treated patients (difference 3.1%; 95%CI -3.4 to 9.6; P = 0.40). These results support oral step-down therapy as a noninferior treatment of IE for select patients.
The findings of POET promise to shorten hospitalizations and IV needs for many patients with IE. However, there are many considerations and caveats:
- Patients were clinically stable on IV antibiotics, without imaging findings of abscess and with no concern for GI absorption of oral medications.
- Caution is warranted for highly virulent, resistant, or uncommon organisms. Microbes such as MRSA and VRE were not well-represented in these studies.
- Prosthetic valve infections were not well-studied (n=22 in POET).
- Right-sided IE was not well-represented in POET (roughly 10% of cases had right-sided involvement), but there is other observational and RCT data outside of POET to support oral antibiotic use for right-sided IE.
Overall, substantial evidence supports oral antibiotic transition for IE showing similar, and possibly better outcomes for the appropriate population of IE patients
How does this change my practice?
In IE patients with common, less virulent IE pathogens (e.g. streptococcus species, MSSA, and coagulase-negative staphylococcus, and non-VRE E. faecalis) who are clinically stable after 7-10 days of IV antibiotic therapy, it is now appropriate to carefully explore oral outpatient treatment strategies. Generally, it remains best practice to do so with infectious disease specialty involvement, since appropriate patient selection remains complicated, with ambiguity in the available evidence.
Source
Partial Oral versus Intravenous Antibiotic Treatment of Endocarditis. N Engl J Med. 2019 Jan 31;380(5):415-424. doi: 10.1056/NEJMoa1808312. Epub 2018 Aug 28. PMID: 30152252
