A research team recently determined that anti-VEGF treatment received by diabetic macular edema (DME) patients is suboptimal, both in the intensity of delivery and the outcomes observed. Time from baseline to receiving the first six anti-VEGF injections was longer than nine months in almost 75% of eyes examined.

Because pseudophakic eyes with DME that are unresponsive to treatment with anti-VEGF therapy qualify for other methods, including intravitreal corticosteroids, researchers in the United Kingdom believe such eyes offer the best opportunity to investigate intravitreal therapeutic patterns in the treatment of DME in a routine clinical setting. In a retrospective review of outcomes in 81 pseudophakic eyes with DME that received at least six anti-VEGF injections, the team sought to understand structural and functional outcomes and examine the detail of anti-VEGF treatment delivery, including the time taken to deliver injections and description of anti-VEGF therapies received (e.g., the frequency of within-class switching).

It took an average of 913 days to deliver a mean of 11.1 anti-VEGF injections. Time from baseline to receiving the first six anti-VEGF injections was longer than nine months in 74.7% of eyes. There was a mean gain of 1.6 letters (-0.03 logMAR) from baseline to the study’s end point. After five anti-VEGF intravitreal injections, the mean central macular thickness was 391.9μm compared with 474.4μm at baseline. In 52 of 79 eyes (65.8%), more than one type of anti-VEGF agent was used.

If the window for observing treatment response is repeatedly missed, the researchers believe it is possible that patients become trapped in a “cycle of recurrence.” Still, they pointed out that it was impossible to differentiate between recurrence and an insufficient response in the current data set.

Despite being candidates for second-line treatment with longer-acting intravitreal corticosteroids, there was a strong tendency for patients to be switched within the class to a second anti-VEGF agent.

“If there is no capacity to review ongoing anti-VEGF therapy in a timely manner, clinicians should feel encouraged to move onto second-line intravitreal corticosteroid therapies rather than switching to another anti-VEGF,” the researchers noted. “Unless further resources become available in clinics, there is a need for longer-acting treatments that reduce treatment demand and the burden on health care resources.”

The study highlights a need to establish a shared protocol for multidisciplinary teams delivering DME services that specifies when and how treatment response should be assessed, defines insufficient treatment response and outlines the appropriate next steps in patients with suboptimal response to first-line therapies.