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Impurity formation

Impurity formation

Supporting the impurity profile definition of your active pharmaceutical ingredient (API) and drug product

API and drug product impurity profile

Identification of your active pharmaceutical ingredient (API) and drug product impurity profiles are a critical aspect of the drug development process, when assessing chemical safety. Impurities can arise from different aspects of drug development including synthesis, degradation, and formulation. To confidently produce a safe final drug product, all possible impurities must be identified, according to regulatory requirements.

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Why choose Consult Lhasa?

Consult Lhasa provide expert risk assessments for impurity formation, built on Lhasa Limited science, that are recognised and trusted by industry and regulatory authorities. Lhasa Limited have been at the forefront of collaborations with industry and regulators to drive in silico approaches and the associated science. The outcome of this work has resulted in the global standardisation of purge submissions and enhanced the understanding of organic compound degradation.

If you need support defining the impurity profile of your active pharmaceutical ingredient (API) or drug product, Consult Lhasa.

How can our experts help you to assess
impurity formation?

Do you need help designing your forced degradation study?
For an API to meet regulations – RDC 53, ICH Q3A – both a theoretical and experimental degradation profile study are needed, ensuring that the conditions in which an API is susceptible to degradation are well understood. A thorough theoretical assessment is essential to designing a scientifically accurate experimental phase. We can identify the theoretical forced degradation pathways of your API and characterise the structures of experimentally observed degradants.

Have you considered impurity formation in relation to packaging and storage?
Drug product packaging and storage should be selected based on the degradation profile of your API. We can identify possible API degradation pathways to consider, reducing impurity formation resulting from packaging and storage decisions.

Does your formulation pose a risk to your drug product?
API compatibility with excipients and excipient impurities should be scientifically evaluated. We can provide an understanding of formulation compatibility, to support your overall ICH Q3B or RDC 53 assessment.

How are degradation factors impacting the stability of your formulation?
Excipients should be chosen considering API properties to enhance drug stability, in line with the ICH Q3B and RDC 53 guidelines. We can provide an understanding of conditions to consider in your formulation design.

Do you need help evaluating your API synthesis, to identify any possible impurities?
Understanding the organic chemistry of your API synthesis is important. This knowledge enables early identification of potential impurities, preventing development delays and health risks. We can evaluate your API synthesis and identify possible impurities.

Is there a risk of impurity presence within your final API?
In some cases, the presence of an impurity in a synthetic route does not create a problem, as impurity properties can lead to its purge during synthesis, meaning the impurity is not present in the final API. We can help to determine if identified impurities will be present in your final API using Lhasa in silico purge tool, Mirabilis, alongside our expert knowledge.

Are potential leachables in your final drug product?
Theoretical knowledge of these extractables is important to identify potential leachables, which may be present in your final drug product. We can provide an assessment of potential leachables, considering your packaging or manufacturing process, in line with current best practice and the upcoming ICH Q3E regulation. Our assessment will guide any further experimental evaluation needed.

We can also conduct a toxicity assessment of any leachable identified, as a non-mutagenic inpurity or potentially mutagenic impurity.

We provide regulatory support

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For qualification of new drug substances produced by chemical synthesis.
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For qualification of impurities in new drug substances produced by chemical syntheses.
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Upcoming guidance for the assessment and control of extractables and leachables (E&L).
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To report, identify and qualify degradation products.
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For assessment and control of mutagenic impurities that reside or are reasonably expected to reside in final drug substance or product, to limit potential carcinogenic risk.

Get in touch

If you are interested in discovering how Consult Lhasa could improve your impurity formation risk assessments, get in touch.