The British Medicines Authority MHRA is performing GMP and GDP Inspections on a risk based strategy. Based on the experience the MHRA answers frequently asked questions. One very interesting Q&A refers to Mean Kinetic Temperature Calculations (MKT). Mean kinetic temperature is a simplified way of expressing the overall effect of temperature fluctuations during storage or transit of perishable goods. The MKT is widely used in the pharmaceutical industry. According to Pharmacopeia definition the MKT "is defined as the single calculated temperature at which the total amount of degradation over a particular period is equal to the sum of the individual degradations that would occur at various temperatures."
According to MHRA: "Mean Kinetic Temperature (MKT) should not be used to compensate for poor temperature control of storage (or transportation) facilities. It may be applied in situations where control is good but where occasional excursions may be encountered. (J. Taylor. ‘Recommendations on the Control and Monitoring of Storage and Transportation Temperatures of Medicinal Products’ The Pharmaceutical Journal (vol 267) July 2001).
It is not possible to obtain a meaningful MKT value from daily readings of simple max / min thermometers as temperature fluctuation is not a linear function. It is noted that some data loggers and building management systems are capable of recording multiple temperature readings over a time period and some offer the function of calculating the MKT over a given time period.
Temperature deviations usually fall into one of two categories: A ‘spike’ deviation where local conditions vary in such a way as the temperature suddenly deviates from and quickly recovers to within the required range and a ‘plateau’ deviation where the temperature lays outside of the range for an extended time period prior to eventual recovery. These two deviations can have differing effect of the product.
It is unlikely that the wholesale authorisation holder will have sufficient data in his possession to assess the potential impact on a specific product of these deviations. In the event of a temperature deviation, the wholesale authorisation holder should seek advice from the marketing authorisation holder of the medicinal item in question.
If the wholesale authorisation holder is able to provide the marketing authorisation holder with details of MKT that the product has been subjected to whilst in his care as well as the times and extent of the temperature deviation, this may assist the marketing authorisation holder in formulating his advice to the wholesale authorisation holder."
Source: MHRA GDP Webpage