Treatment patterns vary
Clinical treatment patterns vary dramatically from country to country and from region to region within countries, Dr. Larsen continued.
The frequency of examination, assessment, and treatment depend on a variety of elements, including practice setting, local regulations, reimbursement requirements, patient factors, and other components.
Under-treatment is common and patients who receive too few treatments have poorer clinical outcomes.
The CATT study clearly showed that anti-VEFG injections of ranibizumab (Lucentis, Genentech) and bevacizumab (Avastin, Genentech) improved and maintained best-corrected visual acuity (BCVA).
There was somewhat better improvement using on-label administration, a mean of 22.9 injections per year, compared to a mean of 13.4 injections per year on PRN schedules, but the differences were small.
During monthly visits, patients on both on-label and PRN regimens showed very good maintenance of vision gained during the first few months over the remainder of the 2-year study period.
Other retrospective studies showed similar results.
A 2.6-year review of ranibizumab PRN showed an initial improvement of 8.4 letters with maintenance of improvement on a mean of 8.6 injections per year.
A review of fixed-interval anti-VEGF dosing found a mean improvement of 14 letters after five years of treatment with 10.5 injections per year.