Home Forums General Discussion Long term and accelerated conditions needed to support storage in a cool dry pla Reply To: Long term and accelerated conditions needed to support storage in a cool dry pla

John O’Neill
Post count: 67

RESPONSE from StabilityHub staff: Some references, definitions and thoughts


Dry place: A place that does not exceed 40% average relative humidity at 20° (68° F) or the equivalent water vapor pressure at other temperatures.
Cool place: A place with a temperature range between 8°C – 15°C

Your long-term condition could be 15C/40% RH (slightly more restrictive than 40% RH at 20C) for the target shelf life of the product in its commercial package.
Accelerated could be 25C/60%RH with test intervals at 1,3, & 6 months, or a variation such as 1, 2 & 3 months if the product fails earlier than 6 months. If the product fails accelerated 25C testing in less than a month, you may need labelling to state, “Do not store above 15C” or more conservatively, recommend storing at refrigerated conditions.

You need to consider some practical implications. The “brand product” referred to is stored at cool dry conditions and probably has a very short shelf life at 25C. If you are competing as a generic, you might have a hard time marketing your product if people don’t want to store it in a refrigerator. A concern is if you store long term in a 40%RH chamber, that condition is something normal customers and retailers can’t typically reproduce.

If possible, you might stick to 25/60 and shorten the labelled shelf-life date as necessary. You might also introduce a more protective package and put a desiccant in it, although that may be out of the question for zone IV (30C).

If the 15C/40% RH long-term conditions won’t result in a reasonable shelf life, you may want to stay with refrigerated conditions and not take the risk for the long-term condition.

If you want to match your competitor’s storage conditions, it would be good to do some side-by-side long term stability studies with the branded product to see if you can match or exceed their shelf life.

You should also generate in-use study data to support what happens to the product after the consumer repeatedly opens the package for 30 days or more, depending on tablet count.

In all cases, check with your QA and Regulatory departments before proceeding.

What do our industry colleagues think?