Dispensing Patterns of Ranibizumab and Aflibercept for the Treatment of Neovascular Age-Related Macular Degeneration: A Retrospective Cohort Study in Australia

Abstract

IntroductionAnti-vascular endothelial growth factor therapy is the standard of care for neovascular age-related macular degeneration (nAMD). The dosage of two licensed agents, ranibizumab and aflibercept, was established through clinical trials; however, it is unclear if either agent is administered as recommended in routine clinical practice. Using pharmacy claims data, we investigated if the dispensing patterns of ranibizumab differ from those of aflibercept 6 and 12 months after treatment initiation.MethodsPrescription data retrieved from the Australian IMS® AUS LRx database were used to identify nAMD patients with one or more claims for ranibizumab or aflibercept between December 1, 2012, and March 31, 2015, with follow-up of at least 6 months. The number of ranibizumab and aflibercept units dispensed was adjusted for baseline patient Medication-Based Disease Burden Index (MBDBI) scores. No difference in the number of ranibizumab versus aflibercept units dispensed was concluded if the 95% confidence interval (CI) limits of the adjusted mean difference between the study cohorts were 1.00 unit or less.ResultsBaseline patient MBDBI scores were similar for the ranibizumab (N = 1235) and aflibercept (N = 959) cohorts. The adjusted mean (standard deviation) number of units dispensed was 5.3 (1.3) versus 5.1 (1.4) at month 6 and 8.9 (2.2) versus 8.9 (2.3) at month 12. The 95% CI limits of the adjusted mean difference did not exceed 1.00 unit dispensed at either time point: 95% CI of 0.09 to 0.32 for an adjusted mean difference of 0.20 at month 6 and −0.23 to 0.30 for an adjusted mean difference of 0.04 at month 12. Mean (standard deviation) dispensing intervals were comparable for both cohorts: 35.3 (19.2) days versus 36.8 (20.0) days at month 6 (adjusted mean difference −1.59 days; 95% CI –2.51 to −0.67 days) and 41.2 (20.9) days versus 41.6 (20.4) days at month 12 (adjusted mean difference −0.40 days; 95% CI −1.70 to 0.91 days).ConclusionsRanibizumab and aflibercept are dispensed in a similar manner by Australian pharmacies during the first year of treatment.FundingNovartis Pharma AG.

Association between visual acuity, lesion activity markers and retreatment decisions in neovascular age-related macular degeneration

“…On application of pre-specified criteria, data from only a subset of eyes could be included, and we therefore consider the analysis as a pilot study for hypothesis generation. Nonetheless, our attrition rates (~55%) are similar when compared with other cohorts of RWE studies published in the literature, which have reported losses of between 55 and 89% [ 32 – 34 ]. A larger RWE cohort study with quantification of retinal fluid volume and a longer follow-up period is planned to confirm the robustness of the present results.…”

Treat and Extend Treatment Interval Patterns with Anti-VEGF Therapy in nAMD Patients

“…Beyond 6 months, approximately one-third of eyes (21–29%) were treated at intervals of 9 to 15 weeks [10]. Dispensing data from regional pharmacies across Australia suggest that licensed anti-VEGFs are dispensed at approximately 5-weekly intervals by Month 6, and at approximately 8-weekly intervals by Month 12 [30]. Although data from these studies are not directly comparable to the present study—the FRB!…”

“…Injection and visit frequencies in this study are broadly similar to the FRB! study [10] and dispensing patterns [30] in Australia. Dispensing data can be used as a proxy for injection data, and a recent study found 8.9 units of both ranibizumab and aflibercept were dispensed in the first 12 months of nAMD treatment [32].…”

“…Briefly, as the dataset only includes data from centres using the Medisoft EMR software that consented to share results, patients included in this study may not fully reflect the target population. EMR data also provide information on the drug prescribed not the drug dispensed; though data for number of injections in Year 1 closely resemble dispensing data from another study [30]. Verification of the validity of the diagnosis or study endpoint is not possible from EMR data, reasons for retreatment are not typically disclosed and OCT data are lacking.…”

Comparison Between Ranibizumab Biosimilar, Innovator Ranibizumab and Bevacizumab in a Real-World Situation

“…In a developing country such as India, under-dosing leading to suboptimal visual outcomes is common. According to a 2017 analysis of a cohort of Australian patients with nAMD, only 40% were still receiving the index treatment 1 year later [ 12 ]. In a study from India, the rate of loss to follow-up was reported to be as high as 51.5% and the most common reasons were non-affordability in 41.4% followed by non-improvement in vision in 28.4% [ 13 ].…”