I currently work in manufacturing/production at a cell-research company where I process autologous cell-therapy products that is in its clinical phase with the hopes of becoming marketed. The most imperative design control I’ve had the chance to be a part of is design changes, which is sensible for me since this step occurs before, during, and after the production process. The most frequent design changes mainly revolve around the technical writing style/format of the standard operating procedures (SOPs) along with the batch record of each lot for each patient that is administered the treatment. Growing, expanding, and overall processing of human cells requires following distinct number-based equations that are written into the batch records which can determine important factors such as the quantity of cryo-protectant added to cells prior to freezing, or how much media must be added to a cell culture. There has been an incident where a set of parenthesis were not included in an equation (similar to how x+y/2 is not the same as (x+y)/2) which would have resulted in many cells dying, but this was luckily pointed out and corrected prior to the initiation of production.

The above situation refers to a pre-production design change that simply addressed a design mistake. What other known methods are there to reduce the likelihood of having to change an aspect of the design process? Quality function deployment (QMD) for example is a proactive method of reducing the frequency of design changes by correlating customer preferences to available resources. What would happen if design changes were implemented too late or not at all?