Purpose
To assess patterns and outcomes of a “treat and extend” dosing regimen (TER) of ranibizumab in patients with age related macular degeneration (AMD).
Methods
332 de novo AMD patients starting Lucentis injections between January 1, 2011- June 30, 2012 were reviewed. 78 were found to be on the extension phase of TER for more than 9 months and included. Patients on TER were initially inducted with monthly injections until there was no evidence of active disease. They then moved to the extension phase and their treatment intervals were extended. Change in visual acuity and central retinal thickness (CRT) during induction and extension phase were recorded. Paired T-test was done to evaluate the change in outcome during each phase, and logistic regression was used to evaluate for confounders.
Results
Patients on TER gained an average of 8.7 letters of vision during induction, and decreased an average of 86.4 µm of fluid on CRT (see Table 1). The worse the baseline vision, the greater the vision gained during induction (p=0.0003). The average vision and CRT at baseline was 20/79 and 338 µm, while the average vision and CRT at first TER was 20/52 and 252 µm. Both change in vision and change in CRT were significant (p<0.001 and p<0.001 respectively). During extension, patients on average gained an additional 2.3 letters (last TER vision 20/48), and had an additional decrease in CRT of 8.2 µm (last TER CRT 242 µm). While the gain in vision during extension was significant (p=0.05), the additional decrease in CRT was not (p=0.21). Overall, patients on average extended to 47.1 days between injections and received 8.2 injections per year. 70.5% successfully maintained intervals greater than 6 weeks with on average 7.1 injections. 22% successfully maintained intervals greater than 8 weeks with on average 5.8 injections. The more injections the patients received prior to extension, the less likely the patient was to extend beyond 6 weeks when extended (OR=0.70, p=0.0001). Cost analysis estimated $20, 614 to treat 1 patient per year on monthly, while it would cost only $14, 256 on TER year 1 with a projected cost of $13, 382 on TER year 2.
Conclusions
TER allows similar visual outcomes to monthly dosing, while reducing the total number of injections, visits, and overall cost. Patients not only maintained the outcomes they gained during monthly treatment, but gained vision when extended.
Keywords: 412 age-related macular degeneration •
466 clinical (human) or epidemiologic studies: treatment/prevention assessment/controlled clinical trials •
688 retina