Tip: Keep pharmaceutical products free from extractables and leachables
By Andreas Tei Agilent Pharma Segment Manager – Small Molecules
The study of extractables and leachables (E&L) as impurities in drug products has become increasingly important. There have been many recalls linked to potentially toxic materials originating from drug containers or parts of the packaging. E&Ls comprise a large variety of compounds, from typical plasticizers as potential endocrine disruptors to genotoxic compounds, such as nitrosamines, polyaromatic hydrocarbons, or toxic elements. E&Ls are detrimental to the integrity of the drug product itself. In addition, the effectiveness of biosimilars could be degraded after contamination with reactive organic compounds or with heavy metal ions.
What’s the difference?
Extractables are compounds that have been extracted from drug containers as a worst-case scenario under drastic conditions. Leachables are usually a subset of extractables found in the drug formulation itself. So-called migrants are compounds that have migrated through the primary container and are also found in the drug formulation. They often originate from the inks on labels or from the environment due to compromised storage conditions and are not a subset of extractables. Figure 1 summarizes the relationships between the different types of contaminants.
Figure 1. Different types of contaminants found in pharmaceutical products.
Why worry about E&Ls?
As FDA data show, the last two years have seen almost as many recalls (2,061) as the previous nine years combined (2,217), and that’s only counting the first seven months of 2014. Defects included the presence of particulate matter, metal, or glass, and also chemical contamination. For example, batches of a gastro-resistant drug were recalled last year because of complaints of unpleasant ‘fishy’ or ‘sweaty’ odors. The root cause was aluminum foil used in the packaging. Although there was no impact on the efficacy or quality of the drug, there was an economic and reputational cost to the drug manufacturer, and to the supplier of the aluminum packaging.
Defining the risks
The U.S. Food and Drug Administration (FDA) has ranked the different drug formulations (liquid or solid) in several risk categories. These depend on the route of administration and the likelihood of interaction between the drug product and its containment. The manufacturer must calculate an analytical evaluation threshold for each compound based on the number of doses and the amount of incorporated drug per day.
An FDA-related organization, the Product Quality Research Institute, has provided definitions to help identify the limits of quantification. Any leachable identified at or above 5.0 µg/day should be reported for a potential toxicological assessment. A safety concern threshold below 0.15 µg/day was defined as the threshold of a leachable compound that would present negligible safety concerns from possible carcinogenic to noncarcinogenic toxic effects.
Analytical approach to E&L analysis
The workflow of sample preparation and the method of detection employed for the determination of E&Ls must be chosen with great care since there is no universal detector that will analyze all possible E&Ls. Usually, employing complementary and orthogonal analytical techniques is the best screening approach for determining E&Ls arising from the packaging. Agilent offers a wide array of complementary solutions that are very effective in E&L analysis. For example…
Figure 2. Select the analytical technique according to the polarity and molecular weight of the analytes (CE – capillary electrophoresis, GPC – gel permeation chromatography, SEC – size exclusion chromatography, IC – ion chromatography).
The technique used depends on the polarity and molecular weight of the compounds of interest (Figure 2).
Agilent solutions for E&L analysis
Cutting edge solutions from Agilent, covering the whole range of analytical platforms for screening extractables in drug product packaging and measuring leachables in drug formulations, are readily available to assist you with your E&L analysis. Agilent understands the challenge of interpreting data from these complex analyses. Take a moment and explore our huge selection of E&L solutions, including data-mining technologies to aid sample comparison, database-driven approaches to quickly identify known compounds, and structure identification tools to help identify unknowns.
Select the analytical technique according to the polarity and molecular weight of the analytes (CE – capillary electrophoresis, GPC – gel permeation chromatography, SEC – size exclusion chromatography, IC – ion chromatography).