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Updated: Jun 8, 2026

Use of Rabbit Eyes in Pharmacokinetic Studies of Intraocular Drugs
Published on: July 23, 2016
Inject and extend dosing versus dosing as needed: a comparative retrospective study of ranibizumab in exudative
Hassiba Oubraham1, Salomon Y Cohen, Sepideh Samimi
1Departement of Ophthalmology, Centre Hospitalier, Orleans, France.
Purpose:
The purpose of this study was to compare two strategies for retreatment with ranibizumab in exudative age-related macular degeneration.
Method:
Two series of consecutive patients treated with ranibizumab in a hospital-based department of ophthalmology were analyzed retrospectively: the first series (n = 52), after as-needed reinjections (PRN group) and the second (n = 38) after reinjections according to the Inject and Extend dosing method (IaE group). Patients' baseline characteristics, type of choroidal neovascularization, and Early Treatment Diabetic Retinopathy Study initial and final visual acuity (at 52 ± 4 weeks) were recorded in each group. Groups were compared by the Mann-Whitney U test or Fisher's exact test.
Results:
Groups were well balanced at baseline for age (P = 0.58), sex (P = 0.66), laterality (P > 0.99), and initial visual acuity (P = 0.33). At 1 year, the mean gain in visual acuity was greater in the IaE group than in the PRN group (+10.8 ± 8.8 vs. +2.3 ± 17.4 letters, P = 0.036), but eyes in the IaE group were given significantly more injections (7.8 ± 1.3 vs. 5.2 ± 1.9 injections, P < 0.001). The number of follow-up visits attended was similar (8.5 ± 1.1 vs. 8.8 ± 1.5, P = 0.2085).
Conclusion:
Patients reinjected by the IaE dosing method had a far better visual outcome but after more injections.
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