Mean Kinetic Temperature also known as MKT is widely used in various industries including Pharmaceutical industry. This article is trying to analyze the relevance of MKT in Pharmaceutical industry for medicines, vaccines etc.
What is Mean Kinetic Temperature or MKT?
If you are looking for more details on Mean Kinetic Temperature, Calculation method and free Excel sheet for calculation, Please go to our separate page on MKT Calculation.
Relevance of MKT in Pharmaceutical Industry
We will briefly explain through a simple example of a vaccine which needs to be stored between 2-8°C at all times until consumed.
How MKT will misguide you?
As an example, suppose you have a medicine which needs to be maintained between 2 to 8°C. If the medicine is kept at 0°C for 2 hours and at 10°C for subsequent 2 hours, the MKT will be 4.9117°C! So the product is acceptable as per MKT. But as you are aware, the medicine might have lost its properties. So do not depend on MKT alone for your decisions.
Example of a Vaccine stored between 2-8°C
The vaccine travels across countries and continents from the manufacturer until the end user. during this entire journey and storage, the vaccine has to be maintained between 2-8°C at all times. For may of the vaccines, the manufacturer recommends that if the temperature goes to zero for even 30 minutes, the medicine loses its properties significantly.
Under practical conditions, it happens that the temperature varies and may also exceed the upper and lower limits few times. We will assume that there is a temperature data logger placed with the vaccine which records data from the factory until the user. Before the vaccine is issued for final use, the data is downloaded and checked. We will assume that the total period including transportation and storage is 45 days. By looking at the graph of the data logger you may observe that the temperature has gone to 11°C for a total of 10 minutes(assume two occurrences of 10 minutes each) and has gone to 0° C three times (assume for a duration of 30 minutes each). We will assume that during the entire remaining period, the temperature was between 5 and 6°C.
As the end user sees deviations in the graph from the acceptable criteria, he needs to further check the MKT for the entire period. The reports generated by most of the data loggers indicate the MKT value automatically (see sample report of data logger ). As per the theory of MKT and as per the ongoing international practice, he can consider the vaccine to be of good quality if MKT is between 2 and 8 °C.
Out of the total duration of 45 days, the medicine has exceeded the limits only for a total duration of 10 minutes. Hence, the MKT will be well within 2-8°C and will be somewhere very close to 6°C (Because the vaccine was between 5 and 6°C for most of the time)
But the vaccine still retains its properties?
In this example, as per MKT calculation the vaccine is 100% acceptable. But as per the manufacturer, if the vaccine has gone to 0°C even for 30 minutes, it loses properties significantly. In this case, the medicine has gone to 0°C three times each for a duration of 30 minutes. Hence, the vaccine has lost its properties significantly. But the user is not aware of this fact. In this case, MKT is misleading. If the temperature had gone above and below the limits many times, the MKT would have been out of the limits and the vaccine would not be accepted. Hencein this case, MKT is clearly misleading.
Is MKT confusing?
In the above case, MKT was absolutely not acceptable.
Theoretically MKT is acceptable. (The Theory says that MKT is the calculated value which indicates whether the concerned material has retained its properties irrespective of the temperature fluctuations)
Hence for each medicine and vaccine, the manufacturer will have to specify whether MKT is acceptable and the user has to give priority to the manufacturer’s recommendation and not to the MKT.
Is MKT acceptable for Temperature Mapping Study & Qualification
We carry out Temperature Mapping study & Qualification for Pharmaceutical warehouses, cold rooms, vans, reefers etc. We have noticed differing opinion on acceptance criteria.There are lot of customers who accept MKT as acceptance criteria. This means that even if the temperature goes below or above the permitted levels few times, a cold room is still acceptable if MKT is within the limits.
However if a medicine is kept at a point which frequently goes below 2°C, the MKT may be still within the limits. However a medicine kept at that point will lose its properties. Hence in our opinion, both MKT and individual readings are important and the qualification also depends on the type of medicine/vaccine stored in such place.
Download the free Excel sheet for calculation of MKT