What is the ATP?

In the context of analytical procedure development and lifecycle management, the Analytical Target Profile (ATP) has become a key concept. It defines the objective and required performance of an analytical method and serves as the foundation for method development, validation, and ongoing performance verification. The ATP ensures that the analytical procedure remains "fit for purpose" throughout its lifecycle.

But how exactly is the ATP defined?

ICH Q14 – Analytical Procedure Development

In Chapter 11 (Glossary) of the ICH Q14 guideline, the ATP is defined as follows:

• "A prospective summary of the performance characteristics describing the intended purpose and the anticipated performance criteria of an analytical measurement."

The concept is further explained in Chapter 3 of the guideline, which states, among other things:

• "An ATP consists of a description of the intended purpose of the analytical procedure, appropriate details on the product attributes to be measured and relevant performance characteristics with associated performance criteria. The ATP includes measurement requirements for one or more quality attributes. The ATP drives the choice of analytical technology. Multiple available analytical techniques may meet the performance criteria. Consideration of the operating environment (e.g., at-line, in-line or off-line) should be included in the technology selection. Once a technology has been selected, the ATP serves as a foundation to derive the analytical procedure attributes and performance criteria for analytical procedure validation (ICH Q2). Formal documentation and submission of an ATP is optional but can facilitate regulatory communication irrespective of the chosen development approach."

This highlights the ATP as a forward-looking statement guiding method development and establishing performance criteria aligned with the method’s intended use.

USP <1220> – Analytical Procedure Life Cycle

In the glossary of USP chapter <1220>, the following definition is provided:

• "The ATP defines the required quality of the reportable value and is a description of the criteria for the procedure performance characteristics that are linked to the intended analytical application and the quality attribute to be measured."

In the main body of the chapter, it further states:

• "A fundamental component of the life cycle approach is the definition of the analytical target profile (ATP) for the analytical measurement. The ATP is a prospective description of the desired performance of an analytical procedure that is used to measure a quality attribute, and it defines the required quality of the reportable value produced by the procedure, aligned with the quality target product profile (QTPP). The ATP is based on the intended use for the procedure and, for quantitative or semi-quantitative procedures, should include upper limits on the precision and accuracy (bias) of the reportable value. The ATP focuses the design goals for a new analytical procedure, serves as a basis for procedure qualification criteria, and provides a guide for monitoring of the procedure during its life cycle. Ideally, the ATP should be specified in way that is independent of the measurement technology; however, in some cases it may be necessary to link it directly to a measurement technology. The ATP can be defined in many ways, but the overall focus of having a procedure with acceptable bias and precision should be part of the ATP."

Together, ICH Q14 and USP <1220> frame the ATP as an essential, scientifically justified tool that ensures analytical procedures remain fit for purpose across their entire lifecycle.