URS / CQA / Design Input

Do these documents all provide the same function? Granted each document has a different format, but from a content prospect all describe what is needed or desired to complete a project. If you could have only one of these documents, which would you select and why?

May I know what is CQA please?

[quote=DURGA PRASAD]Meyert,
May I know what is CQA please?[/quote]

CQA = Critical Quality Attribute

Since the principles of Quality by Design (QbD) for pharmaceutical manufacturing first emerged a few years ago, many companies have been struggling to understand the key concept of design space—what it is exactly, and how to establish it. The recent CMC Strategy Forum, however, started by examining a more fundamental issue: how to determine the critical quality attributes (CQAs) of a product—that is, the characteristics that define its quality.

Thanks Graham.

URS : Is the basic requirement that is required. This is whole set of document that I would like to give a vendor. The vendor will understand and gives me a proposal.

Design inputs : Its the document that is developed based on the inputs given by the manufacturers and based on our functional needs and Regulatory needs.

Critical Quality Attributes: These arise from the functionality of the products and functionality of the process or functionality of the material of construction.These are detearmined by Risk analysis and tools of Risk assessments like Failure Mode and Effects Analysis (FMEA) and Preliminary Hazards Analysis (PHA) methods.

For a Validation/Qualification scientist URS is the prerequisite step. From which the design specification evloves based up on the crtical quality attributes that evolve out from functionality and QbD(quality by design concepts).


[b]CQAs Do Not Necessarily Equal Specifications

Another important conclusion was that one should not necessarily expect to see a one-to-one relationship between CQAs and specifications. One reason for this is that several product variants identified as CQAs may be detected by a single test method and therefore built into a single specification.

Also, some attributes might be included in specifications even if not considered critical. This would occur if they were deemed to be a measure of process consistency, or conducted to meet a compendial or regulatory requirement, such as an identity test. Anthony Ridgway of Health Canada suggested coining a new term, “standard quality attributes,” for this category of attributes. [/b]

To be honest, I don’t care what the document is called or what acronymns its given - neither do the regulators for that matter.

CQA, Design Input, URS can be totally different entities or the same thing, depending on what you are implementing (as quite rightly pointed out by Graham in a previous posting)

As long as I’m given a URS thats understandable, we can add the priorities later (CQA, CSF etc etc) - the point I’m making I suppose is that we have “requirements” and “priorities” - and usually never the twain shall meet- you only get your priorities (or whatever you are measuring at the time).

I was leaning towards them fullfilling the same requirement. Design input was directed at 820 device guidance, where the Design Input drives the Design Output and validation/verificaiton. Different words but from 50,000 feet in the air - the same.

The structure of the URS has been carefully set by the regulators for very specific reasons. If you do not work in the pharma/medical device/biotech industries then read no further and please desist from commenting.

Without doubt the User Requirements Specification (URS), is the most critical of documents and yet, the most often bungled. Whether the system is purely mechanical, or a mix of electro-mechanical, or solely a software program, the successful compilation and execution of the Installation Qualification (IQ) (for installation), Operational Qualification (OQ) (for functionality) and the Performance / Product Qualification (PQ) (for operability), is dependent on an User Requirements Specification (URS) containing clear, concise and testable requirements.

Once the end user requirements specification is documented, agreed and approved they form the basic URS Level-1 document. The engineers (or vendor) can then commence the preliminary design to establish exactly what functions are required for each of the items specified in the user requirements specification, the end user has listed. Once this functionality is documented and approved it forms URS Level-2 document. This is the final level of the URS unless software is used.

If software is to be used, the URS Level-2 document, is passed to the code writers. As the code is written, lines, or groups of lines, of code must be attributed to the individual functions that necessitate their presence. The completion of this task results in the completion of the URS Level-3 document.

Developing the URS to this level is unique in most industries, but is, standard practice in strictly regulated industries, as it is a major building block in the creation of quality software. The URS Level-3 document, contains all the traceability which is deemed mandatory for software assessed to be critical to product quality, in the pharmaceutical regulated industries.


URS does not equal CQA, CQA of WFI for example is microbiological and chemical release accepatance criteria, (eg endotoxin, nitrates, hardness etc…), conductivity and temp…

These in my mind do not translate to urs or design inputs… read FDA guide on PV and ASTM E2500-07 stds for more info, …

Hi Mr. Alex,

Really agrreed with your opinion on requirements of URS. URS is the basis of any development, not in regulated world even in the laymans world. Till time the URS is not precise, clear & concise end result will not be robust and as desired.

CQA (Critical Quality Attributes) are the speciifcation/ features to maintain the life cycle / quality of product, it may be possible at initial requiremnet gethering there is no CQA in URS, while on letter on may wish to incorporate it in…based on product usage experience…what is really happening terms are interchanged so frequent in the world. Guidelines are speaking some times dot-to-dot & some times in between the line…common interpretation is really a big deal, with which industries & forums are struggling.

Happy Reading !