Purpose Evaluating 12-month visual and anatomical outcomes after switching to faricimab in diabetic macular oedema (DMO) patients with sub-optimal response to aflibercept 2mg.

Patients and methods Sixty-two eyes of fifty patients were enrolled in this retrospective study at a UK tertiary referral centre. This consisted of DMO patients with sub-optimal response to aflibercept 2mg who were switched to faricimab. Four loading injections of faricimab were given at monthly intervals, followed by a treat-and-extend regime. The sub-optimal response was defined as CST >325 microns or >20% from best CST despite aflibercept 2mg at less than or equal to 8 weekly intervals(≤q8w) having completed a loading dose of aflibercept 2 mg (6 injections at monthly intervals). Outcome measures were best-recorded visual acuity (BRVA), central subfield thickness (CST), and treatment intervals.

Results Baseline BRVA was 67.6 (±11.8) letters and CST was 406.4 (±105.9) µm, and the mean treatment interval was 6.5 (±1.8) weeks. At baseline, 24.2% of eyes were treated every 4 weeks (q4w), 19.4% every 6 weeks (q6w), and 56.5% every 8 weeks (q8w). After the 4th faricimab loading dose, 54 patients continued on treat-and-extend faricimab. BRVA improved to 70.4 (±12.7) letters (p=0.007) while CST reduced to 372.8 (±132.0)µm (p=0.070). The mean injection interval improved to 7.4 (±2.6), 95%CI[0.1, 2.9]weeks. Subjects were followed up for 57.1 (±19.7) weeks, with a mean of 7.92 (±2.53) faricimab injections. At the latest follow-up, BRVA was stable at 68.7 (±14.6)(p=0.918) letters. CST had reduced further to 343.1 (±117.5) µm(p=0.034). Treatment intervals at the latest follow-up were: 3.2% q4w, 9.7% q6w, 30.6% q8w, 3.2% q10w, 11.3% q12w, 1.6% q14w, 6.5% q16w, with 53.2% on ≥q8w. The mean injection interval had also improved to 9.2 (±3.1) weeks(p=0.122).

Conclusion In this study, DMO patients with sub-optimal response to aflibercept 2mg experienced improved anatomical outcomes and extended treatment intervals while maintaining vision by switching to faricimab.

Kamal El-Badawi: No conflicts of interest to declare. Benjamin Scrivens: Educational grant from Roche. Oluwaniyi Eke: Travel bursary and advisory board Bayer, speaker fees Roche. Rehab Ismail: No conflicts of interest to declare. Serena Salvatore: Advisory board for Bayer, Roche; Speaker fees and travel bursary from Alimera Sciences, Roche Products Limited, Bayer. Lina Kobayter: Advisory board and travel bursary from Roche Products Limited.. Speaker fees from Bayer, Alimera Sciences and Roche Products Limited.

Funding was not received for completion of this study. The authors of this study have requested funding from Roche to cover submission costs. No confirmed funding at the point of this submission

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