Intravitreal injections are a necessary treatment for wet AMD, diabetic macular edema (DME) and retinal vein occlusion (RVO). A new study in BMC Ophthalmology suggests individualized treat-and-extend regimes in daily practice may result in high patient compliance and visual acuity gains nearly comparable with those found in large clinical trials.

AMD, DME and RVO usually require chronic treatment using intravitreal injections with anti-VEGF agents, and many trials using as-needed, fixed and treat-and-extend regimes have been done to find the best treatment interval. However, numerous real-world studies reveal a high rate patients lost to follow-up within two years of treatment.

In the current study, the investigators retrospectively analyzed two years of real-world experience with an individualized treat-and-extend injection program.

Since 2015, researchers from Germany switched their treatment regime from as-needed to treat-and-extend in their AMD, DME and RVO patients. Of 102 subjects, 59 completed a two-year follow-up. Patients underwent visual acuity testing, OCT imaging and slit lamp exams prior to every injection. At each visit, the researchers gave patients an injection, and based on any changes found on OCT, the treatment interval was adjusted by increasing or reducing treatment in two-week steps.

After one year of treatment, 34 AMD patients had visual acuity (VA) gains of 7.4±2.2 ETDRS letters (with an injection frequency of 7.4±0.4), nine DME subjects had VA gains of 6.1 ± 4.7 (injection frequency: 8.4 ± 1.1) and 16 RVO patients gained 9.7±4.5 letters  (injection frequency of 7.6±0.5).

At two years of treatment, all patients’ VA continued to improve: wet AMD patients’ VA gain was 6.9±2.1 (injection frequency: 12.6 ± 0.7); DME patients added 11.1 ± 5.1 letters (injection frequency: 14.0±1.0) and RVO subjects gained 7.5 ± 5.0 letters (injection frequency: 11.2±0.9).

Planned treatment exit after two year was achieved in 29.4% of patients with wet AMD; however, no patients could exit treatment at one year in this group. Additionally, no DME patients could leave treatment after the one- and two-year mark. For RVO subjects, 31.3% could leave at two years, although no patients could exit treatment after year one.

Patients’ persistence was 94.1% during the follow-up, the researchers noted.

The treat-and-extend approach can prevent over-treatment and also simplify treatment by extending intervals where the patient notices an improvement and VA stabilization between injections, the study noted.

“The patient knows that at each visit an injection will be performed, and it is much easier to schedule visits and guide patients in daily practice, because no uncertainties about the treatment exist. If patient and physician act together closely in terms of treatment continuity, best and stable visual gains as well as a high patients’ persistence can be obtained,” the researchers wrote in their paper.

 Usually, treat-and-extend leads to a slightly higher injection frequency than as-needed, but to a considerably lower visit frequency, which is regarded as a positive aspect for chronic therapy from the patient’s point of view, the investigators added.

Volkmann I, Knoll K, Wiezorrek M, Greb O, Framme C. Individualized treat-and-extend regime for optimization of real-world vision outcome and improved patients’ persistence. BMC Ophthalmol. March 30, 2020. [Epub ahead of print].