A process harmonization assessment (PHA) is an efficient tool to thoroughly assess the differences between separate sets of
equipment processing a specific molecule. The main components reviewed in a PHA include: process flow, process parameters,
equipment capability, and raw materials. A PHA document evaluates the risk to the technical success of a technology transfer
by understanding the important process and equipment-related issues early in the process. A PHA document also discusses when
differences between sets of equipment may affect critical design parameters for the process such as mixing, heat transfer,
column flow rates, and gradient control. Early process development and scale-up may not need every aspect of a PHA document,
but node-to-node transfers generally realize great benefit when complete assessments are performed.
Technology transfer consists of the transfer of technical information about a process from the laboratory to pilot-scale,
pilot- to commercial-scale, and commercial node-to-node transfers. Each transfer has varying levels of data and restrictions.
A node-to-node transfer has the largest breadth of process data, but also has the highest restrictions caused by critical
process parameters and other process and equipment parameters defined by a registered process. When contemplating a technology
transfer, a well thought out process to assess the inherent differences between facilities and equipment sets must be followed.
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One of the most efficient ways to do this is by conducting a process harmonization assessment (PHA). The PHA compares process
and engineering parameters from the current process facility and equipment set to a proposed facility and equipment set. The
main components of a PHA include the review and comparison of process flow, process parameters, equipment capability, cleaning,
and raw materials. Each of these components also includes a discussion of differences in parameters between the facilities.
Action items may be created to understand the impact of the differences. These action items may include mixing studies or
additional laboratory data to support the changes to the process that are required as a result of the transfer.
Technology transfers early in the development cycle have fewer strictly designed process steps and few if any critical process
parameters (CPPs). A simple assessment of the most basic process flows, process parameters, yields, and purities may be enough
for a PHA at this development stage. After process development reaches pilot-scale or production-scale, further details in
the assessment are critical to reduce risk from unknown variables and ensure both the receiving site and sending site understand
the process and the equipment that is being transferred. A PHA document may undergo revisions over the course of a technology
transfer as the design progresses, and will continue to be revised as the process changes.
Process Flow Review
The process flow review section of a PHA establishes how the receiving site will fit the process into its major pieces of
equipment. This is the earliest portion of the PHA that can be completed. In many cases, a process flow review is completed
during due diligence or the initial process fit. Each piece of equipment is selected to enable the major process steps to
flow with approximate equipment capacity, product flow through the facility, and process timing. This section may take the
form of a process equipment diagram with the process flow shown in a basic process and instrumentation diagram. The process
equipment flow creates the inventory of equipment needs at the receiving site and will be the basis of any initial capital
project needed to procure major equipment, if necessary.