Process capability increases to more than 2.0 with this type of control. Process capability can rise to the point where nonconformances
become an annual event rather than a daily occurrence. This control is called adaptive because process and product data are
fed forward to the process-control management system. APC instructs controllers so that the current processing step is adapted
according to the known condition of the materials. This flexibility further reduces variability within specifications and
increases process capability.
In addition to quality and compliance, benefits include reduced product variability, which ensures safety and efficacy in
drugs and devices. FDA is increasingly concerned about the need for constant active dosing levels in patients. This level
of process control will reduce product variability to help ensure constant dosing.
Level 5, FDC, adds the remaining elements to the process-management picture. It brings control over the environment. It measures
and controls elements that are largely constant but drift over time or vary because of events such as normal wear, abnormal
wear, maintenance, or software upgrades. The following situations describe examples of what FDC controls:
A manufacturer lost control of its chemical sterilization process. Process parameters on SOPs were being followed. Bacteria
were found on product tests as many as four days later. Several clean-up and sterilization procedures were conducted. For
six weeks, no cause or solution could be found. A large percentage of the manufacturer's product underwent sterilization,
which caused significant supply-chain delivery problems. Employees ultimately found that a different type of oil was being
used in one of the vacuum pumps. When the oil was replaced with the normal oil, the problem was eliminated.
The residual gas analyzer that provides environmental control could have detected the change in air composition before the
operation started a second sterilization batch. In this case, only one batch would have been affected. FDC's classification
capability would also have instructed the operator or mechanics where to look for the problem.
A manufacturer lost several batches of a sold-out product because of low active-release rates. During manufacturing, the product
was a capsule with a hole that allowed the active to enter the patient's body over a period of time. The capsule was held
in place by a spring-loaded clamp and laser drilled. During routine maintenance, the standard springs were not available,
so stronger springs were used. The stronger springs increased the clamping pressure and forced the active out of the capsule
during the drilling operation. This deviation caused the low release rates. FDC could have detected the increased clamping
pressure and alerted the operator and the mechanic of the problem before the first batch was run, thereby saving several batches
of the sold-out product.
FDC detects machine failure, machine drift, and environmental changes long before procedures or routine checks would identify
such conditions. FDC detects failures through monitoring machine parameters and analyzing them in relation to each other.
For example, suppose a machine running in a partial-vacuum condition demonstrates pressure within specification, but the vacuum
pump is pulling more electrical current than it normally does. Suppose the pressure varies within the chamber more than normal.
FDC would detect this anomaly and send a message to the operator to check the seal or the pressure plate. This action would
occur well before an out-of-specification situation could occur.
FDC enables excellent process control and anticipates problems before they occur. FDC allows the manufacturer to achieve the
perfect or "golden model," the conditions that produce the product with the right attributes all the time with minimal variation.
The conditions include the processing parameters such as temperature, pH, conductivity, pressures, speeds, and product attributes
from the previous operation. The conditions also include environmental factors such as the manufacturing air and machine statistics
such amp usage, pressures, and speeds. The process, environmental, and machine conditions are recordeded to achieve the golden
model. The golden model can then be attained every day with FDC and APC.