Pegfilgrastim Prefilled Syringe Fill Volume for Dose Accuracy
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing injection systems face challenges in delivering accurate bolus dosages of pegfilgrastim due to drug transfer losses and syringe dead volumes, which can lead to inconsistencies in pharmacokinetic and pharmacodynamic properties.
Innovation Solution
A method of filling a syringe with a pegfilgrastim solution that accounts for estimated drug transfer losses and syringe dead volumes by filling the syringe with a volume that includes the target extracted volume plus these losses, ensuring accurate delivery.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the syringe is filled with the target extracted volume only, then the filling process is simple, but the actual delivered volume is inaccurate due to drug transfer losses and dead volume
Solution Approach 1:
The syringe is pre-filled with an optimized volume that anticipates and compensates for future drug transfer losses and dead volume. The fill volume is calculated as: V_fill = V_target + V_dead + V_transfer_loss, ensuring the target dose is delivered despite system inefficiencies.
Solution Approach 2:
The fill volume parameter is optimized to a specific range (645-650 µL) that accounts for the relationship between dead volume, transfer losses, and target dose. This parameter adjustment transforms the system from inaccurate to precise without changing the physical structure.
2Quantity of substance
If the syringe dead volume is reduced, then more drug is delivered, but the syringe design becomes more constrained
Solution Approach 1:
Rather than redesigning the syringe geometry to reduce dead volume, the solution changes the fill volume parameter to compensate for the fixed dead volume. This maintains manufacturing ease while achieving accurate drug delivery through mathematical optimization of the fill specification.
3Measurement precision
If drug transfer losses are minimized through process optimization, then dosage accuracy improves, but the manufacturing process becomes more complex
Solution Approach 1:
Instead of implementing complex process controls during manufacturing to minimize transfer losses, the solution pre-calculates and incorporates the expected losses into the fill volume. The manufacturing process remains simple while achieving accuracy through advance compensation in the fill specification.
Solution Approach 2:
The drug transfer losses, which are inherently harmful to dosage accuracy, are converted into a beneficial design parameter. By measuring and incorporating the loss into the fill volume calculation, the previously harmful effect becomes a predictable, compensated factor that ensures accurate dosing.
Data Source
AI summary
A prefilled syringe and a method of filling a syringe with a pegfilgrastim solution to provide a target extracted volume of pegfilgrastim solution from the syringe are described. A method includes selecting the target extracted volume of pegfilgrastim solution, determining an estimated drug transfer loss, determining an estimated syringe dead volume, filling the syringe with a volume of pegfilgrastim solution comprising at least the target extracted volume plus the estimated drug transfer loss plus the estimated syringe dead volume.