Real-time diabetic retinopathy severity score level versus ultra-widefield leakage index-guided management of diabetic retinopathy: Two-year outcomes from the randomized PRIME trial

The prospective PRIME trial applied real-time, objective imaging biomarkers to determine individualized retreatment needs with intravitreal aflibercept injections (IAI) among eyes with diabetic retinopathy (DR). 40 eyes with nonproliferative or proliferative DR without diabetic macular edema received monthly IAI until a DR severity scale (DRSS) level improvement of ≥2 steps was achieved. Eyes were randomized 1:1 to DRSS-or PLI-guided management. At the final 2-year visit, DRSS level was stable or improved compared to baseline in all eyes, and mean PLI decreased by 11% (p = 0.73) and 23.6% (p = 0.25) in the DRSS-and PLI-guided arms. In both arms, the percent of pro re nata (PRN) visits requiring IAI was significantly higher in year 2 versus 1 (p < 0.0001). The percent of PRN visits receiving IAI during year 1 was significantly correlated with the percent of PRN visits with IAI during year 2 (p < 0.0001). Through week 104, 77.4% of instances of DRSS level worsening in the DRSS-guided arm were preceded by or occurred alongside an increase of PLI. Overall, consistent IAI re-treatment interval requirements were observed longitudinally among individual patients. Additionally, PLI increases appeared to precede DRSS level worsening, highlighting PLI as a valuable biomarker in the management of DR.