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Investigate OOS Results When They Occur

Investigate OOS Results When They Occur

November 9, 2020
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Manufacturers want to avoid Out of Specification (OOS) results at all costs. This includes all results that don’t fall within the specifications that are established in drug applications, drug master files, or by the acceptance criteria set by the manufacturer. The discovery of an OOS can severely impact the manufacturing process.

When an OOS is found, an investigation starts – and manufacturing processes related to the violation grind to a standstill. Since an OOS result can lead to a delayed batch release, it is in manufacturers’ best interests to do everything in their power to limit this outcome.

Learn from OOS Results – and Avoid Future Ones

The best way to learn is often through lived experiences. So, if your lab has faced an OOS result, take it as an opportunity to begin a thorough investigation to prevent it in the future. These legally mandated internal investigations are best applied when following five crucial steps, also known as the Five Golden Rules of OOS investigations:

  1. Even though the investigation is required, you should do it because you want to – not because you have to. Understand the benefit of the investigation.
  2. Follow the evidence. Don’t pursue red herrings, as false conclusions will only cost you.
  3. Use clear language.
  4. Don’t rush to end an investigation.
  5. Don’t make the same mistake twice.

Beyond these five golden rules, there are several more steps manufacturers can take to prevent future OOS results. Keeping track of results and data is essential, as is implementing software that makes adhering to standards much simpler.

For more on how to avoid OOS results, consult our full checklist here.


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