Primary and secondary packaging change programs are a routine part of the pharmaceutical product maintenance lifecycle. Changes can be as a result of material obsolescence or rebranding for market share. The implications for the industry are that when changing label component materials or adhesives the impact on the product needs to be considered not only in terms of the possible interaction with the product but also the impact on the overall leachable burden in the same way as for other primary packaging components. Studies have demonstrated that there is potential for the migration of compounds from booklet label components through high density polyethylene (HDPE) bottle material.
With regards to the extractable – leachable correlation, the leachable burden over the shelf-life of the product was found to be a subset of the extractable profile. However, dependent on the extraction solvent(s) and techniques, extracted concentrations may provide an unrealistic over-estimate of this burden. Therefore, the extraction study needs to be designed relative to the product properties and resultant extraction profiles evaluated, to provide for appropriate targeted migration studies.
The extractable – leachable correlation from this study demonstrates that harsh extraction techniques and solvents, such as reflux extraction when compared to Soxhlet extraction and heptane compared to water, may provide unrealistic extraction profiles with more compounds than necessary being monitored in subsequent migration (leachable) studies.
The extraction profile obtained for nasal product booklet labels, while dependent on the extraction solvent used, is also influenced by the extraction technique employed. The data presented indicates that harsh extraction techniques and solvents should be avoided in extractable studies as they are not representative of the true leachable burden.