A customer wanted to expand its nicotine lozenge product from just Zone 2 (25°C/60%RH) to include Zone 4b (30°C/75%RH). The lozenge, had an eighteen-month shelf-life in Zone 2. What packaging would be needed to allow for the geographic expansion?
FreeThink conducted an ASAPprime® study. The active (nicotine) is chemically very stable; however, when it dissociates from being bound to an ion exchange resin, it is volatile and leaves the packaging. This loss of assay limits the shelf-life.
The ASAPprime®-designed study involved six conditions over three weeks, with a graph of the design shown below.
Analysis of the data using the ASAPprime® software showed excellent model fit, as seen in the residual graph below:
From the analysis, the predicted shelf-life in the current PVDC blister packaging could be compared to that observed long-term, as seen below:
The 25°C/60% predictions versus found values can be seen in more detail in the following graph (mean ASAPprime® prediction in blue with red and green being one standard deviation range on predictions, black squares are real-time observed values):
As can be seen, there is a good match between the predictions and real-time findings. The product shows very high sensitivity to humidity (B = 0.10), so that achieving a reasonable shelf-life in Zone 4b (30°C/75%RH) would best be achieved by either packaging in bottles with desiccant or in blisters placed into foil overwraps with desiccant. In either of these configurations, the probability of remaining within specifications after the end of shelf-life (18 months) is greater than 95%.