Biologics and regenerative therapies are driving the pharma industry deeper into the cold chain. Vials and pre-filled syringes that require refrigeration and sub-zero storage are becoming more commonplace. As anyone involved with the inspection and packaging of these products knows, the time spent out of cold storage is limited and, when not handled properly, adds stress to the process.
For years, we have looked at methods to increase our efficiency through process improvement methods. One of the first things Lean teaches is “One Piece Flow”, meaning that if possible, perform an action on a product and immediately send it to the next step. Don’t accumulate hundreds or thousands of products that are only partially finished. This simplifies scheduling and prevents the production of large numbers of products that might be defective.
Now enter a cold chain product in a vial. There are many possible technical reasons One Piece Flow is not always possible in vial processing: balancing filling to inspection to packaging is not always feasible, settling time after filling is needed, sub-lots may be labeled for multiple markets, inspection results may initiate additional inspection processes (which can’t be done on a labeled product), etc.
So often during vial processing, the vials are accumulated after one process, placed in cold storage, and when needed, brought out to warm up to room temperature before being processed through the next step (inspection or packaging). This wasted time adds no value to the product.
The warming period adds to the excursion time, the warming vials take up space that could be used for something productive, and the stress to the operations staff increases as their allotted processing time slowly ticks away. Often, these are not short amounts of time; eight to twenty-four hours are not uncommon equilibration times. So why do they need to come up to room temperature? Condensation.
Condensation forms on these cold vials and wreaks havoc down the line. Inspection equipment detect condensation droplets as defects. Manual visual inspectors can’t see real defects with water droplets in the way. Normal pressure sensitive labels don’t stick to wet glass. Wet vials slip out of operators’ gloved hands. Cardstock cartons soften and warp when wetted. Furthermore, standard packaging equipment is not designed to run in wet environments.
There are methods to eliminate condensation or mitigate its effects. Low humidity rooms can decrease the temperature requirement for equilibration which decreases the excursion time. This method requires a balance to ensure staff is comfortable in these rooms (below 30%RH does not agree with the human body).
An accumulation conveyor with downdraft fans can warm vials quickly by pulling ambient air around the vials as they slowly move down the conveyor. Placed upstream in a small climate controlled room, the vials are dry and at room temperature often in less than 30 minutes and can be processed as normal.
Specialty components can work with slightly damp vials. There are pressure sensitive label adhesives that can stick to wet and/or cold vials. Different carton materials can withstand water droplets. Many ink formulations are not water soluble. And keep in mind, condensation may occur later in the supply chain or while with the end user. The components need to be able to withstand moisture at these points anyway, so why not incorporate water resistant technology to make the packaging process more efficient also.
The point is, do not just accept that cold chain products need hours of non-productive time to warm up before being processed. Be creative. Talk to component and machine vendors. Talk to your facility engineers. Equilibration time reduction will save you money in the long term and will decrease your stress in the short term.
(Source: IPS – Integrated Project Services, LLC)
