A2, Figure 1
shows examples of changes that may occur during a method's lifecycle and illustrates the actions that may be taken.
A2, Figure 1. Changes that may occur during a method’s lifecycle and illustration of the action that may be taken.
A change in method operating conditions is made inside the method design space (e.g., changing an HPLC flow rate from 1 mL/min
to 1.5 mL/min for a method where a range of 1mL/min to 2 mL/min was proven during the method design stage). No action is required;
implement change. This change corresponds to an adjustment from the regulatory perspective.
A change in method operating conditions occurs outside the method design space (e.g., changing a flow rate to 0.8 mL/min
for the method used in the previous example, change to a method noise factor, change to a reagent source). The action is to
perform a risk assessment to consider which characteristics in the ATP may be impacted by the change and then perform an appropriate
method performance verification study to confirm the change does not impact the method's ability to meet the ATP.
A change to location is made. The action is to perform a risk assessment to consider the risks created by the change. Take
appropriate action to ensure method controls are adequately installed following the change (e.g., provide training, transfer
knowledge, establish controls for new supplier of reagents). Perform an appropriate method performance verification study
to confirm that the change does not adversely impact the method's performance.
A change is made to a new method or technique (i.e., a change that requires a new MDS to be established for improvement or
business reasons, for example). The action is to perform method development and understanding (stage 1) and method qualification
(stage 2) to demonstrate conformance of the new method to the ATP.
A change impacts the ATP (e.g., specification limit change, a need to apply the method to levels of analytes not considered
in the original ATP). The action is to update the ATP, review the existing method qualification data, and confirm if the method
will still meet the requirements of the existing ATP. If not, revisit the method design stage and requalify the updated method.
Phil Nethercote* is analytical head for global manufacturing and supply at GSK, Shewalton Road, Irvine, Ayrshire, Scotland KA11 5AP, Phil.W.Nethercote@gsk.com
and Joachim Ermer, PhD, is head of quality control services chemistry at Sanofi in Frankfurt, Germany.
*To whom all correspondence should be addressed.