Introduction and methods

Partial Oral Treatment of Left-Sided Infectious Endocarditis – The POET Trial – Long Term Follow-up

Presented at ACC.19 by Henning Bundgaard (Copenhagen, Denmark)

Infectious endocarditis is treated with intravenous (IV) antibiotics for up to 6 weeks, and patients have to stay in hospital. There is a high rate of in-hospital complications. Mortality rates are also high. Complications mainly occur in the early phase. Once the patient is stabilized, receiving IV antibiotics is the main reason for staying in the hospital. Hospital stay per se may cause complications.

The POET study tested if a change to orally administered antibiotics and continuous IV administered antibiotics have similar efficacy and safety, in a Danish nationwide randomized study of 400 stabilized patients with endocarditis (non-inferiority trial). The short-term results at 6 months have previously been reported. This presentation shares the long-term results, up to 3.5 years. Patients with left-sided endocarditis based on the modified Duke criteria caused by Streptococci, Enterococcus faecalis, Staphylococcus aureus or Coagulase-negative Staphylococci were included. The primary endpoint was a composite of all-cause mortality, unplanned cardiac surgery, embolic events confirmed by imaging and relapse of bacteremia with the primary pathogen.

Main results

• The primary endpoint was observed less often in de oral vs. IV treatment group (26.4% [n=53] vs. 38.2% [n=76], HR: 0.64, 95%CI: 0.45-0.91, P-log-rank: 0.01).
• Unplanned surgery was not significantly different between groups (6.0% [n=12] vs. 9.5% [n=19, P=0.2).
• The rate of embolic events did not differ significantly between groups (2.5% [n=5] vs. 2.5% [n=5], P=0.8).
• The rate of relapse of positive blood culture was similar in both groups (4.0% [n=8] vs. 5.5% [n=11], P=0.4).
• Death occurred significantly less often in those on oral treatment, as compared with IV treatment (16.4% [n=33] vs. 27.1% [n=54], P=0.009).

Conclusion

This long-term follow-up of the POET study showed that the efficacy and safety of changing to oral antibiotic treatment were non-inferior to continuous IV antibiotic treatment in stabilized patients with left-sided endocarditis. The medium length of stay reduced by 16 days, so was about halved.

Discussion

The discussant Gurusher Panjrath (Washington, DC, USA) congratulated the investigators with the well-designed study on the effort to reduce multi-drug resistance. The primary outcome was met; now how can we extrapolate these findings? The data are very strong, but it should be noted that the pathogens may be a little different in places other than Denmark. Moreover, the availability or use of different antibiotics may vary per country. We need more information and collaboration on the situation across the ocean. There was 100% follow-up, and of course that raises the question whether that can be achieved in a real-life population. So, Panjrath concluded, we need a bit more information before we jump to implementation, but we are certainly on that road.

- Our coverage of ACC.19 is based on the information provided during the congress –

The results of the POET trial were published simultaneously in NEJM