Number of Anti-VEGF Injections Increase Over Time in Patients with nAMD

Marion Schroeder

A recent observational study analyzed and compared the number and interval of anti-vascular endothelial growth factor (anti-VEGF) injections in patients with neovascular age-related macular degeneration (nAMD).

The team of investigators, led by Marion Schroeder, Department of Ophthalmology Lund University, observed the number of injections increased during the follow-up time from the earliest to latest index period, considered the first injection of anti-VEGF agents.

They also noted a continuous improvement in baseline visual acuity (VA), which led to improved VA outcomes during study follow-up.

Methods

Investigators performed a non-interventional, observational study with inclusion of patients with treatment-naive neovascular AMD (nAMD) in order to follow-up on treatment with pooled anti-VEGF agents and clinical outcomes in Sweden.

A total of 41 clinics input patient data into the Svenska Makula Registret (SMR) on when intravitreal treatment was started for newly diagnosed nAMD and during follow-up time period.

For inclusion criteria, investigators included eyes of treatment naive nAMD patients who were ≥50 years of age at index date and with ≥1 injection between February 2007 - December 2017. The index data was defined as the first ranibizumab, aflibercept, or bevacizumab injection for a patient’s eye with nAMD.

The study took place from January 2007 - June 2018, for a 1-month pre-index period. Further, the study timeline was divided into 4 index periods: 2007 - 2010, 2011 - 2013, 2014 - 2015, and 2016 - 2017. A follow-up took place in a period of 1 - 3 years.

Additionally, the primary outcome was considered the evaluation of the number of injections after 12 months of treatment after the initiation of an anti-VEGF agent.

Measurements of distance visual acuity (VA) were determined using the standardized methods of visual acuity testing. Following VA measurement in the Snellen chart, the unit was converted into Early Treatment Diabetic Retinopathy Scale (ETDRS) letters.

Findings

Over the index periods, a total of 11,528 eyes in 10,499 patients (cohort 1) were included at baseline, with a 1-year follow-up. In cohort 2, a total of 5253 eyes in 4917 patients were included with a 2-year follow-up and cohort 3 consisted of 2520 eyes in 2389 patients with a 3-year follow-up.

From the 2007 - 2010 index period to the latest 2016 - 2017, the number of injections in each index period was increased.

Data show the mean number of injections per year was 6.2 ± 1.4 injections following 1 year of treatment in the first index period and 8.3 ±  2.0 injections after 1 year of treatment in the latest index period.

Additionally, the mean number of injections was 4.8 ± 1.6 after 2 years of treatment in the first index period versus 6.7 ±  2.4 after 2 years of treatment in the second index period.

In the 3rd cohort, in the index period 2014 - 2015, eyes received ≥2 consecutive treatments within a 12 - 16 week interval in 5.2% during year 1, in 15% during year 2, and in 17.5% in year 3.

Furthermore, in the duration of injection intervals in different index periods, the last mean injection interval at month 12 was 73 ± 34 days in cohort 1, 67 ± 32 days in cohort 2, and 68 ± 33 days in cohort 3.

During the month 24 follow-up, the last interval was 71 ± 33 days for cohort 2 and 66 ± 31 days for cohort 3, while the last interval in the 36-month follow-up for cohort 3 was 67 ± 32 days.

In determination of visual acuity, the baseline ETDRS VA was 57.7 ± 13.5 letters for the index period 2007 - 2010 (n = 1585). Data show the baseline VA increased to 62.1 ±  13.4 letters in indexed eyes during 2015 - 2017 (n = 3126), all P <.0001.

Takeaways

Investigators noted an observation of more stability and less decline of visual acuity over time following a later index period in the study.

“A possible reason might be that patients are diagnosed and treated earlier and better implementation of treatment routines that allow a more individualized regimen and increased persistence of treatment,” they wrote.

The study, “Exploration of real-world outcomes and treatment patterns in patients treated with anti-vascular endothelial growth factors for neovascular age-related macular degeneration in Sweden,” was published in Acta Ophthalmologica.