A stability study shows how the quality of a drug substance or drug product changes over time under the influence of temperature, humidity and light. Samples are stored in qualified chambers at defined conditions — such as long-term, intermediate and accelerated conditions from ICH Q1A(R2), for example 25 °C/60% RH or 30 °C/65% RH long term and 40 °C/75% RH accelerated — and pulled for testing at scheduled time points.
The results support the shelf life, retest period and storage instructions in the marketing authorisation. ICH Q1E describes how to evaluate the data, including regression analysis to estimate the time at which a quality attribute would reach its acceptance limit. After approval, ongoing stability studies continue on commercial batches.
Why it matters in GMP
21 CFR 211.166 requires a written stability testing programme, and EU GMP Chapter 6 requires an ongoing stability programme for marketed products. Missed or late pulls, untested samples and failures that were not escalated are common inspection findings, because they weaken the evidence behind the shelf life printed on every pack.
- Calculate pull dates from time zero, per condition, with defined pull windows.
- Flag late pulls and treat them as deviations.
- Trend results and escalate failures or out-of-trend results.
How Swat iQua Suite handles it
Swat iQua Suite calculates the pull schedule on the server from time zero for each storage condition, with pull windows, and blocks pulls until the protocol is approved. A late pull is allowed but flagged as a deviation, and an internal pull creates a testing sample automatically. The module is seeded with four ICH storage conditions, sends a daily pull reminder, produces ICH Q1E regression trend and shelf-life reports, and escalates a failure or out-of-trend result to CAPA.