Related Experiment Video
Updated: Apr 30, 2026

Use of Rabbit Eyes in Pharmacokinetic Studies of Intraocular Drugs
Published on: July 23, 2016
Integrating disease progression models, non-clinical pharmacokinetic data and treatment response endpoints to
Objective:
To rapidly identify patients who will ultimately respond to 1 year of therapy, and optimize their inter dose interval.
Materials And Methods:
An intravitreal (IVT) ophthalmic dosing paradigm was designed based on clinical efficacy, nonclinical pharmacokinetics (PK), and disease progression modeling. Relevant non-clinical PK models were used to extrapolate IVT drug concentrations to patients.
Results:
Modeling predicted that > 80% of patients who would respond to 1 year of IVT treatment with an improvement in best-corrected visual acuity (BCVA) could be identified after the first 2 doses of treatment. These 2 initial doses produced ~ 75% of the maximum improvement in BCVA attainable. Moreover, the models also predicted those patients who responded after 1 year of treatment may tolerate an extension of the inter dose interval to 12 weeks without significant deterioration of BCVA. In contrast, > 70% of responsive patients who did not respond to 1 year of treatment showed inadequate responses after 2 doses.
Conclusions:
These models use data from 2 doses to identify those patients likely to benefit after 1 year of treatment, and thereafter can lengthen their inter dose interval without deleterious effects. This method identifies potential treatment responders early, and lengthens the inter dose interval during long-term administration while allowing non-responders to pursue alternative therapies earlier, thereby minimizing risk to the patient.
Related Concept Videos
Impact of Pharmacokinetic–Pharmacodynamic Models: Regulatory Decisions
Dosage Regimens: Designs and Approaches
Pharmacokinetic–Pharmacodynamic Relationship: Problems
Drug Dosing in Renal Diseases: Dose Adjustments Based on Drug Clearance and Elimination Rate Constant
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...
Dosage Regimen: Individualization

