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PDA Glossary

PDA Glossary of Pharmaceutical and Biotechnology Terminology

PDA Technical Reports are highly valued membership benefits because they offer expert guidance and opinions on important scientific and regulatory topics and are used as essential references by industry and regulatory authorities around the world. These reports include terms which explain the material and enhance the reader’s understanding.

The database presented here includes the glossary terms from all current technical reports. The database is searchable by keyword, topic, or by technical report. Each definition provided includes a link to the source technical report within the PDA Technical Report Portal.

Browse Terms by Title


Browse Terms by TR #

  • Cycling

    A study designed to stress test the product and provide specific information on its ability to withstand transient high and low temperature excursions during distribution and storage. Typically the study conditions are outside of ICH accelerated conditions.(TR53)

  • Date of Manufacture

    For small molecules, the date of manufacture of a drug product is considered to be the initial date that an active ingredient has been added during manufacturing. For biologics the date of manufacture can be determined in multiple ways and should be consistent with internal quality systems and the product license application. (TR53)

  • Excursion

    A temperature or humidity deviation from conditions such as those specified by product labeling or shipping specifications. (TR53)

    Measurement that exceeds an alert, concern, or action level/limit by either a discreet value or an increasing/decreasing trend. (TR69)

  • Finished Materials

    This term refers to items such as drug substances, drug products, finished product held in bulk before final packaging, and clinical trial materials that are likely to be stored for significant periods of time and are also subject to the risks of distribution. (TR53)

  • Freeze-Thaw

    A study designed to determine the effect of repeated freezing (typically to -20 °C), and thawing back to labeled storage conditions (typically +5 °C for refrigerated products, and +25 °C for temperature products). Freeze-thaw studies are designed to evaluate the impact of short-term excursions where product may be exposed to sub-zero temperatures, followed by standard shipping conditions. (TR53)

  • In-Use

    In the hands of the end user who can be the health professional or the patient. In-Use refers to the time period where product is in the custody of the end user or health care professional. (TR53)

  • Stability Budget

    A stability budget considers the results of long-term, accelerated, freeze-thaw, and temperature cycling studies to determine the amount of time out of storage that a drug substance may experience without any significant risk to its quality. Firms have used the idea of a stability budget to assign permissible time out of storage for packaging and labeling operations for refrigerated drug products for some time. This concept has been expanded in the present document to include storage and distribution as well. (TR53)

  • Storage

    The retention of pharmaceutical products in a location such as a warehouse; the storing of pharmaceutical products up until their point of use. (TR53)