Related Experiment Video
Updated: May 10, 2026

Tumor Treating Field Therapy in Combination with Bevacizumab for the Treatment of Recurrent Glioblastoma
Published on: October 27, 2014
Is it necessary to use three mandatory loading doses when commencing therapy for neovascular age-related macular
G Menon1, M Chandran, S Sivaprasad
1Frimley Park NHS Foundation Trust, Frimley, UK. geeta.menon@fph-tr.nhs.uk
Purpose:
To determine whether a Pro Re Nata (PRN) regimen with three initial mandatory loading doses results in better functional and anatomical outcome compared with a PRN regimen without initial loading when using intravitreal bevacizumab in patients with minimal classic or occult choroidal neovascularisation secondary to age-related macular degeneration.
Methods:
Patients were randomised (1 : 1) to Loading (LD group) or No Loading (NLD group) and treated with open label intravitreal bevacizumab. In the LD group, patients received two mandatory doses after the baseline dose before entering the PRN phase and in the NLD group, patients did not receive mandatory doses after the baseline dose. Six-weekly evaluations were performed up to week 54 and retreatment was done based on OCT criteria. Visual stability and reduction in central retinal thickness were compared between groups.
Results:
49 patients were in the NLD group and 50 patients were in the LD group. At the 12-month end point, 84% of the patients in the LD group achieved visual stability (<15 letter loss) compared with 67% of the patients in the NLD group (P<0.05). The mean reduction in central macular thickness was 105.35 μm in the LD group and 81.45 μm in the NLD group (P>0.05). There was no significant difference in scores of VFQ-25 questionnaire testing between the two groups and no serious ocular or systemic side effects were observed.
Conclusion:
The results supported our hypothesis that a loading dose leads to slightly better visual stability in terms of proportions of patients experiencing moderate visual loss, but did not support the hypothesised difference in anatomical outcome.
Related Concept Videos
Determination of Multiple Dosing Parameters: Loading and Maintenance Doses
Rational Dosage Regimen: Maintenance Dose and Loading Dose
In most cases, drugs are administered repetitively or infused continuously to maintain a steady-state concentration in the body. At a steady state,...
Dosage Regimen: Fixed Dose
Fixed-dose regimens can be used for various routes of administration, including intravenous (IV) injections and oral medications. For IV administration, a predetermined amount of the drug is...
Drug Accumulation During Multiple Dosing: Intermittent IV Infusions
Dosage Regimen: Multiple Oral Dosage
Open Angle Glaucoma: Treatment
Drugs such as carbonic anhydrase inhibitors, α2- and...