Stability: Back to the Basics - Part III

Part III: Measuring Shelf Life— Product Efficacy of API and Finished Drug Products

20170911-AlcamiStLouisFacility-0019-of-0148-6803-1.jpgIn this five-part blog series, Alcami scientific experts, Russell Crothers and Adam Keisker, go “back to the basics” to examine the importance of stability in pharmaceuticals.

The Federal Drug and Food Administration (FDA) states that “Stability studies should include testing of those attributes of the active substance that are susceptible to change during storage and are likely to influence quality, safety, and/or efficacy. The justification of individual and total upper limits for degradation products should be based on safety and/or efficacy consideration.”

Safety, quality and product efficacy work together in stability studies of Active Pharmaceutical Ingredients (APIs) and finished drug products. Through stability testing, pharmaceutical companies like Alcami have the ability to identify and trend shelf life and their affects on efficacy as samples are exposed to time, light and temperature.

In order to learn why stability studies are so important in establishing efficacy, you must first understand these definitions: 

Stability studies definitions

The FDA regulates API and finished drug product efficacy, and both must demonstrate effectiveness to gain approval. In finished products, stability storage and testing are taken into consideration. Stability storage and testing demonstrate how products withstand degradation when exposed to varying temperatures, humidity and light.

All finished products approved by the FDA have established levels of efficacy, and potency can significantly impact side effects. For instance, a drug may have very good efficacy but is so unpleasant to take, due to side effects and amount of degradation, that its actual effectiveness within the margin of safety is extremely limited. With stability storage and testing, we are able to identify these potential issues.

In stability studies, the inherent stability characteristics of the molecule, particularly the degradation pathways, must be identified. Degradation correlates with the effectiveness and the efficacy of the finished product in order to measure the shelf life of a product.  Scientists are able to identify the degradation in the product form and the suitability of analytical procedures for the quantification of both the active substance and degradation products to establish retest periods. Thus, stability studies are ultimately determining the shelf life of the finished product.

A shelf life determines a timeline for when a product is considered safe and effective under relevant storage conditions. Such factors as temperature and relative humidity can be used to accelerate these processes effectively allowing for trending and prediction of shelf life.

Fundamental degradation factors involving the efficacy and shelf life of APIs/finished drug products are listed below: 

Fundamental degradation stability factors involving the efficacy and shelf life of APIs/finished drug products

There are provisions in place regarding the particular formulation, as well as the container, to remain within particular chemical, microbiological and physical specifications as guided in the International Conference on Harmonisation (ICH) to ensure maximum efficacy and safety of the product.

Thank you for your interest in learning more about stability. Alcami offers stand-alone stability services as well as in-process studies with the expertise to guide you from the design of the stability study for each phase of development through the evaluation of the data accruing to ICH Q1E. 

Stay tuned for the next post in this series, Part IV: Stability and the Importance of Storage Conditions.

Read Part I: The Importance of Stability in the Evaluation of “Quality Attributes” of Pharmaceutical Drug Products"

Read Part II: The Impact of Stability on the Safety of API and Drug Products.

About the Authors

Russell Crothers is a leading authority for the generation, review, and edits of stability protocols at Alcami's St Louis site. He is responsible for the execution and management of the commercial and clinical development products for stability and maintains compliance with both ongoing and new regulatory requirements. His work as Lab Materials Support IV here is best showcased in his ability to streamline and digitize processes resulting in more efficient, precise stability services. He is the Power of Attorney for Controlled Substances at the Alcami St. Louis site. Russell graduated from Greenville College with a B.A. in Biology and has since joined the Alcami team in 2015.

Richard “Adam” Keisker is the Lead Sample Control Unit (SCU) Coordinator for Alcami’s St. Louis site. He oversees the coordination of analytical samples in a pharmaceutical testing environment, specifically the stability programs protocol approvals, storage, sets and release for analytical testing. Adam graduated from Lindenwood University with a B.A. in Chemistry with a concentration in forensics. 


1              Medbullets Team 2017 “Efficacy vs. Potency”
2              Medilexicon, 2017, MediLexicon International Ltd, Brighton, UK  “Effectiveness”
3              American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
4              FDA (1987). Guideline for submitting documentation for the stability of human drugs and biologizes. Rockville, Maryland: Food and Drug Administration, Center for Drug and Biologizes, Office of Drug Research and Review.

Topics: Stability Blogs