EVIAN study shows feasibility of early vitrectomy for postoperative exogenous endophthalmitis compared with antibiotics

The phase 2 EVIAN study (Early Vitrectomy and Intravitreal Antibiotics for Post-Operative Exogenous Endophthalmitis) (NCT 04522661), published in Nature Communications Medicine,¹ found that performing early vitrectomy for acute endophthalmitis can offer better and faster visual outcomes than the current antibiotic-first approach, reported lead author Mahiul M. K. Muqit, MBChB, MRCOphth, and colleagues. He is from Moorfields Eye Hospital NHS Foundation Trust, and the Institute of Ophthalmology, University College London, both in London.

According to a press release issued by Moorfields Eye Hospital, the current treatment guidelines for endophthalmitis exist only for cases that develop after cataract surgery. This approach involves administration of repeated intravitreal antibiotic injections during the early phase, with vitrectomy reserved for cases that do not respond to the antibiotic regimen.

Prospective, randomized controlled clinical trial

The investigators undertook a multicenter study to assess the feasibility of randomizing patients to undergo early vitrectomy within 48 to 96 hours after becoming symptomatic compared to the current standard patient care that involves repeated, immediate intravitreal antibiotic injections and delayed vitrectomy.

Patients were included who had confirmed postoperative endophthalmitis that was associated with symptomatic visual loss and a best-corrected visual acuity (VA) that was worse than 35 Early Treatment Diabetic Retinopathy Study letters. The primary outcome measure was the feasibility and acceptability of carrying out a randomized clinical trial of early surgical treatment compared to the current standard of care.

What did this feasibility of this early vitrectomy study show?

The study, conducted at 21 enters in the UK, included 63 patients. Maqit and colleagues reported that 6 months after early vitrectomy was performed, the VA improved by a median of 40 letters (range, 28-70 letters). This was in contrast to patients who were treated with an initial 6-month antibiotic regimen who had a median increase of 13 letters (range, 0-66 letters). The investigators pointed out that this non-significant difference corresponded to a between-group difference of 24 letters, adjusted for baseline, in favor of early vitrectomy (p = 0.139).

The results showed a higher rate of non-serious adverse events observed in the patients initially treated with antibiotics (68%) compared to the vitrectomy group (47%). There was a higher rate of retinal detachments, i.e., eight cases (24%) in the antibiotic group compared with two cases (6.7%) in the vitrectomy group.

The investigators emphasized that the visual improvements occurred earlier for patients, bringing relief and recovery from what can be a painful condition as well as removing the psychological shadow of potential sight loss from them sooner, as mentioned in the press release.

The conclusion reached by the EVIAN trial was that it met the primary endpoint of feasibility in conducting a trial to randomize the target population at multiple centers. While the visual improvement in the vitrectomy group was not significant compared with the antibiotic group, the effect on the VA indicates the potential meaningful benefit of vitrectomy compared to the standard of care treatment, which can now be tested in a phase 3 clinical trial.

In commenting on the study results Muqit, said: "This important new study shows the potential short-term and long-term potential benefits to patients given an early vitrectomy if they contract endophthalmitis after their eye procedure. As using this intervention at diagnosis shows clear potential to improve clinical outcomes, we now intend to take this forward to a definitive phase 3 randomized clinical trial that can definitively answer this question."

Reference
1. Muqit MM, Pavesio C, Wang Y, et al. Early vitrectomy and intravitreal antibiotics for post-operative exogenous endophthalmitis (EVIAN): a randomised control trial of feasibility. Commun Med. 2026; https://doi.org/10.1038/s43856-026-01664-w