By Bart Reitter
Interpreting PAT
The march toward the complete Process Analytical Technologies (PAT) solution continues unabated. Vendors, end-users, integrators, consultants, OEMs and everyone in between are talking about PAT. End user organizations are issuing RFIs and writing specifications defining their vision of PAT, and pharmaceutical OEMs are figuring out ways to incorporate PAT instruments into their machines.
At this year’s INTERPHEX in New York it was difficult to walk past any booth that didn’t mention PAT in some capacity, and the acronym could be overheard in conversations throughout the show.
However, despite the familiarity of the now-well-known acronym PAT, the interpretation of just what this acronym means can be quite varied. PAT is now a familiar part of industry vernacular. But knowing what a deployment looks like, how to deploy it, and ultimately how to deliver a financial justification for deploying it is not so well known.
A cursory discussion with several different people will reveal the disparity that exists with how to interpret PAT. Invariably however, there seem to be two general discussions that take place when talking about PAT, and they lie at opposite ends of a PAT solution.
The first interpretation is that PAT is all about the instrument. Terms like Near-Infrared (NIR) and Raman have suddenly become frequently used in the pharmaceutical industry, even though they’ve been around for decades. This is further confirmation that the FDA’s guidance is being well received. However, a PAT solution hardly stops at the instrument. Spectroscopy is undoubtedly an important part of a PAT solution, but it’s only a piece of the puzzle.
The second interpretation involves Multivariate Analysis (MVA) software. MVA software is a powerful (but also not new) class of software that often uses proven statistical techniques like Partial Least Squares (PLS) or Principal Components Analysis (PCA) to analyze complex data sets like the chemical attributes of a drug compound. While extremely powerful and necessary for a PAT deployment, MVA is also only a piece of the puzzle.
The piece that makes the whole PAT solution tick and facilitates the efficient transfer and interpretation of all of that instrument data is often not spoken about and sits quietly between these two well-known pieces of the larger PAT puzzle.
Go With the Flow
The flow of data in a PAT solution begins at the instrument. The spectrometer takes a reading about moisture content or blend uniformity from the process. This “snap shot” of data taken every few seconds results in thousands of data points. The data is usually sent to the interface software that came with the instrument. This software is used to configure the instrument and acquire data and is unique to the specific device. This means that with multiple different types of instruments deployed there are multiple types of software interfaces to manage. Try to send all of that data to a plant historian or an MVA software package and it will require hours upon hours of work.The solution to this issue is a “universal” software interface that effectively acts as SCADA for analytical instrumentation. The concept is a software suite capable of operating the majority of spectrometers and other process analytical instruments while providing all of the capabilities required for on-line analysis in much the same way that a SCADA software solution can interface to multiple PLCs. Indeed, there exists software today that can interface to multiple instruments and provide the foundation for a comprehensive PAT solution. The concept of having a single platform to manage all of the instruments was born in the R&D environment. But similar to PAT itself, technology is flowing from R&D into manufacturing and concepts previously deployed in the lab only are now finding their way to the production environment.
Framing this type of software solution as simply SCADA for instrumentation, however, is to undersell its value. In addition to a single instrument interface, these types of software solutions also provide a single database format for all data, instructions, and administrative information, a single interface for diverse MVA and other software programs, extensive methods development capability, and locked-down methods and tools for compliant applications.
Connecting with the Future
As drug manufacturers begin to roll out their PAT solutions, many will undoubtedly look to standardize and define common platforms for instrument and software solutions alike. But the reality of the production world that exists today is that there is an abundance of different “PATesque” solutions already deployed around the world. Companies have experimented with X-ray, acoustic, NIR, and Raman PAT solutions for decades now.The reality of the pharmaceutical world is that PAT is not new, even though the FDA’s recent acceptance and endorsement is. Similar to the world of automation, the latest spate of mergers and acquisitions have forced differing automation and enterprise platforms to live in harmony. The world of instruments is no different.
Another reality is that despite efforts toward standardization, there will be an abundance of different spectroscopic solutions deployed in manufacturing plants around the world. The mergers and acquisitions have assured that. Connectivity to all of those instruments will prove to be a monumental effort unless a universal solution is deployed.
Having the capability to connect not only to multiple instruments but also to be able to send spectral data to plant historians and MVA software solutions alike will provide immeasurable value for companies who are trying to deploy their PAT solutions quickly and shorten their time to value. These technological and financial benefits will likely provide a strong motivation for the deployment of standardized PAT instrument interface software.
