Controlling Impurities In Drug Manufacturing


Impurities in pharmaceutical products do not offer any therapeutic benefit for the patient and sometimes they are potentially toxic. Impurity level is a critical quality attribute for a drug substance or a drug product. Impurity control is one of the most important tasks in a process scale up.

Impurities can be controlled by understanding the formation, fate and purge of the impurities during the manufacturing process. They also can be controlled by setting up appropriate controls at places where they either enter or form during the manufacturing process of drug substance and/ or drug product.

Here at PCI Synthesis, we have developed various approaches to controlling impurities.

  • Material controls: Based on the knowledge gained from a synthetic route, impurities can be controlled by testing them according to set specifications. This enables us to eliminate the impurities before beginning the process.
  • Process controls: These are the controls which are put into place in order to monitor and adjust the process by ensuring that an API or its intermediates conform to its specifications.
  • End product testing: Impurities which are formed during late stages of product development can be controlled by end-product testing with appropriate specifications.

Some of the control strategies for impurities that we regularly implement at PCI Synthesis include, but are not limited to, the following:

  • Control of input material attributes (e.g., starting materials, API, reagents, intermediates, excipients, primary packaging materials) based on an understanding of their impact on processability or product quality.
  • Control of in- process materials.
  • Product specification(s).
  • Controls for unit operations that have an impact on downstream processing or product quality (e.g., the impact of drying on degradation).
  • In-process or real-time release testing in lieu of end-product testing (e.g. measurement and control of CQAs during processing).
  • A monitoring program (e.g., full product testing at regular intervals) for verifying multivariate prediction models.

If you have questions about controlling Impurities, please contact us

Impurity control is an essential process in API or drug manufacturing. At PCI Synthesis, it is not only one of the most important tasks in process scale up, but is also one more element in our commitment to quality control in all aspects of the development process.