Validating Process Validation

By Agnes Shanley,

PharmaManufacturing.com

FDA’s new draft guidance gets to the essence of what process validation is, and isn’t. Have you read it yet?

Safe pharmaceutical manufacturing, as we know it today, could not exist without process validation. Introduced in the 1970s, when FDA was still known as the Bureau of Drugs, the concept was originally designed to protect the public against the impacts of variability in sterility assurance, but was extended broadly to drugs and devices.

It aimed to ensure that any process would do what its developers intended it to, and make products of reproducible quality. The concept worked.

It also became a monster. Over time, misunderstandings about validation promoted a rigid, bureaucratic approach to manufacturing. Concerns have led some companies to lock in inefficiencies, generate reams of defensive documentation, and reject new technologies or approaches, even if they would improve both process and product.

In addition to being far more engineering-focused and much more clearly written than the previous guidance, the new document stands out from the prior guidance in that it:

• outlines, clearly, a life-cycle approach to process validation
• presents the essence of what Quality by Design is, without going into the terminology
• emphasizes the importance of process control, calling out the importance of both QA professional and the line operator in providing feedback and
  continued process verification.
• specifically mentions process stability and process capability
• mentions the potential role of simulation
• touches on the importance of continuous operator training
• highlights the need for a crossfunctional approach, even specifying the different disciplines that should, ideally, be involved.
• discusses the need for data analysis, within and between product batches, mentioning the most relevant places to find this information:
• discusses how PAT and real-time data access would change the approach to Performance Qualification

So what was so wrong with the prior guidance? I decided to check the wording of the 1987 document more carefully. It made me wonder about a few things….for one thing, where on earth did the magic number three (for the infamous “three validation batches”) come up? It wasn’t in that document.

The earlier document had already paved the way for QbD by highlighting the importance of drug development, yet it seemed to focus more on data collection than interpretation. It was also somewhat diffuse, taking many paragraphs to discuss control limits, and including lengthy asides on process examples that sounded like religious commentary on sacred scripts.

Some companies are already taking a very modern approach to process validation, and developing techniques that would allow processes to be adjusted on the fly. Last month, a meeting of the American Institute for Chemical Engineers (AIChE) in Philadelphia offered a number of practical examples showing how these concepts are being applied.

One expert from a U.K. company showed how multivariate models can be used to adjust automatically for differences in raw material sourced from different suppliers so that the resulting product’s quality is always consistent.

That is the future, but for many operations today it might as well be science fiction.
Recent informal surveys in our magazine have found that pharmaceutical development and manufacturing are still using mainly univariate rather than multivariate data, and that many companies aren’t even performing process capability analysis. The sigma level of drug manufacturing, experts say, remains around 3. At the same time, some FDA reviewers and inspectors may not be in synch with the new guidance. Audience members at one AIChE session asked why some FDA reviewers appear less interested in hearing about their carefully developed “design spaces” than in specific process values.

Even if there’s more work to be done, documents like this draft guidance provide clarity and a basis for open discussion and benchmarking. FDA is accepting comments on the document until January 19, via http://www.regulations.gov). I urge you to write with any constructive criticism. In the meantime, write us and let us know what you think.

FDA publishes guidance on process validation

The US Food and Drug Administration (FDA) has issued draft guidance on process validation, updating its 1987 document to incorporate advances in manufacturing technology and thinking.

Modern risk management and quality system tools and concepts form part of the FDA’s new thinking, which is in keeping with its initiative entitled “Pharmaceutical CGMPs for the 21st Century – A Risk-Based Approach”.

Biological products, including active pharmaceutical ingredients (APIs), are the focus of the document, which by implementing manufacturers should align their process validation activities with the product lifecycle concept and existing FDA guidance.

The document defines process validation: “as the collection and evaluation of data, from the process design stage throughout production, which establishes scientific evidence that a process is capable of consistently delivering quality products.”

Covered under the guidance are some general considerations for process validation, such as having an integrated team that has members with a variety of specialisations, and more specific recommendations.

These recommendations span the three stages covered by process validation, namely process design, process qualification and continued process verification.

The three stages cover the adoption of process validation from development and scale-up through to commercial manufacture and beyond to provide ongoing assurance.

Included in the document are sections covering capturing process knowledge and understanding and facility design and equipment selection.

Documentation and analytical methodology are also covered in the guidance, which can be found here .

Asahi Kasei gains TechniKrom’s bioprocess business

Japanese chemicals firm Asahi Kasei has ramped up its bioprocessing operations with the acquisition of US industrial processing specialist TechniKrom’s biopharmaceuticals business.

The integrated offering, which will operate as a wholly-owned Asahi subsidiary, will combine TechniKrom’s portfolio of processing equipment and validation services with Asahi’s hollow-fibre and membrane adsorption technologies.

The deal, financial terms of which have not been released, builds on the firms’ collaboration centred on Asahi’s range of industrial Planova virus removal filters and, according to the Japanese company, will help drugmakers lower production cost and improve product quality.

Yasuyuki Yoshida, president of Asahi Kasei Medical, said the deal seems like a perfect fit in terms of the firm’s global expansion plan. He explained that the integration provides “a base for the development, production, and sale of equipment and systems in the US.”

While the US market for biologics and biotherapies has grown continually since it first emerged as a going concern 25 years ago, the development of follow-on biologics as patent expiry looms looks set to shift the expansion into a higher gear.

In recent months for example, several US majors like Pfizer and Merck & Co have expressed an interest in growing their generic biologics portfolio in preference to investing in the development of non-biologic drugs.

While such big pharma interest would have proved a barrier to entry for smaller firm’s wishing to claim a share of the traditional drug market, the greater technical difficulties associated with manufacture of biologics may mean there is more scope for technically proficient biotechnology companies to prosper alongside the industrial giants.

In addition, the Food and Drug Administration’s (FDA) recent approval of the first drug to be derived from transgenic-animals; GTC Biotherapeutics’ anti-clotting therapy Atryn, suggests that US demand for effective bioprocessing solutions will continue growing. All of which looks good for Asahi Kasei TechniKrom in terms of developing its business in the US.

TechniKrom President Lou Bellafiore was also pleased about the new relationship. He said that: “In addition to our existing products and services that we will continue to offer, we are extremely excited about the line-up of novel bioprocess separations products that Asahi Kasei TechniKrom will introduce."

HVAC Excellence Test Validation Procedures

HVAC Excellence Test Validation Procedures

By John Hohman

Developing the content

Test content is developed through the input of technical experts. Traditionally called

“focus groups”, these groups have transitioned into groups now called “Subject Matter

Experts” or SME’s. To develop any national test, a minimum of five and a maximum of

nine technical experts from three states are essential. Ideally, the more participation from

more states is desired and sought.

A work session for the SME’s at the developmental stage generally consists of a “job and

task” analysis of the work done within the field of occupation that the SME’s represent.

A job and task analysis attempts to identify elements of the occupation that can be

identified as individual jobs. It continues to identify tasks that need to be completed

within each job element. There may be many jobs within an occupation and subsequently

many tasks that need to be done before a job can be completed. This is the first step in

developing “Content Validity.”

Depending on the scope of development, SME’s may be involved in identifying other

elements of the occupations, such as: tools, equipment, work environment, conditions of

work that relate to ADA (America requirements, etc. Sometimes this information is

already sufficiently documented and doesn’t require additional study.

Developing the structure

After the job and task analysis has been completed, the same or another group of SME’s

is retained to develop the structure of the test. The structure of a test is sometimes

referred to as the “table of test specifications” and is used to determine the content and

emphasis of the test. This is the part of the test building process that establishes

“Construct Validity.”

It is generally understood that a group of questions (items) may constitute a test of

knowledge in a given field of occupation. Developing the table of test specification

maintains a degree of control on the content of the test. This process also satisfies the

condition of “Semantic Validity” whereby the labels relate to the occupation being

evaluated. This control of content helps to insure that one aspect of validity is maintained,

the second step for “Content Validity.”

The structure or table of test specification identifies the number of questions/items to be

applied to a given section/category of the test. Doing so maintains the content

relationship of the test while individual questions, relating to the section/category, may be

changed or randomly selected from a test item bank.

Developing the items

Questions on a test are typically referred to as “test items.” Each item takes the form of a

multiple-choice question. The item is made up of three parts: 1) the question, called the

“stem”, a single correct answer, and a set of plausible, possible answers called

“distracters.” The number of distracters sometimes helps to elevate the difficulty or level

HVAC Excellence Test Validation Procedures

By John Hohman

of the test. Typically there are four choices, one correct and three plausible distracters.

There can be up to seven choices for a given item.

The same or a similar occupational group of SME’s are involved with the development of

test items. Items are generated in many different ways, and they are guided by the “table

of test specifications.” More items are generated than the test requires. Often, items are

abandoned for many reasons and additional items are required to maintain the size or

length of a test.

Items are reviewed for “Bias” toward protected groups by persons other than the SME’s.

The test developer selects individuals that have a high degree of sensitivity to bias

language to review the developed test items in an attempt to eliminate all or most

language that may offend or bias an item for a protected group of people.

Pilot Testing

Pilot testing is an important step in the development of a test. Pilot testing consists of

identifying individuals within an occupation that are at approximately the target level of

the test. For example, a technician level test may require selecting individuals who have

some level of experience within the occupation to pilot the test.

Pilot participants are selected by knowledgeable people within the occupation. They are

asked to select participants who they feel are at the specific level the test is designed.

Through this selection process come aspect of “Criterion Related Validity” is generated.

Typically, selected participants have already been evaluated to some degree by the person

who selects them. Therefore, some degree of relationship exists between the level of the

participant and the level of the test. Other criterion related tests results might be used to

validate this process for a pilot group.

The size of the pilot test group will be selected to generate sufficient data. Depending on

the number of people within the occupation, the number within a location, or the number

of individuals that can be found to volunteer, will determine the pilot test group.

“Face Validity” is generated at this point in the test development process. Face Validity

refers to the recognition of the test title, test categories, and test items as being part of the

field of occupation. Individuals who pilot test are asked to respond or comment on each

of these parts of the test.

The pilot test also asks participants to mark items, words or phrases that might have an

impact on protected groups in a second attempt to eliminate bias.

Item Analysis

Item analysis is the process of technically reviewing the structure, response, and fit of a

given item and the relationship of that item to the rest of the test. Through item analysis

HVAC Excellence Test Validation Procedures

By John Hohman

some levels of “Reliability” validation can be obtained. Item analysis can use any or all

of the following statistical analysis:

Kuder Richardson Formula - KR 20 & KR 21

Cronbach Coefficient Alpha

Spilt-half Reliability Coefficient

Level of Difficulty

Easiness Scale

Coefficient of equivalence

Spearman-Brown

Standard error of measurement

Final Formatting

The item analysis will reveal items that are not working as expected. Those items will

either be eliminated or the deficiency repaired. The test will be formatted to the correct

number of total questions and each section/category is reviewed for the correct number of

questions according to the table of test specifications. All other spelling and formatting

difficulties are eliminated.

Test Delivery

Delivery of the test follows prescripts required for all national tests and requires a level of

security. The delivery process consists of identifying individuals to proctor the test who

have a high degree of personal conviction and agree to the requirements of handling and

proctoring a national test.

Continuing Analysis

Test results are continually monitored on a periodic basis. As score anomalies occur,

whole tests or individual items are scrutinized for problems. When a test shows a

significant level of problems it is slated for review ahead of its scheduled review period.

All tests are reviewed on a three year basis.