Comparative Analysis of Impurity Profile

Impurity research is an important content throughout drug development, production and marketing. Impurity profile analysis of drug products is the basis of impurity research, and impurity control based on impurity profile is a specific practice of the concept of "quality by design" in impurity research. In the consistency evaluation of generic drugs, the FDA requires a series of comparison of impurity profiles, such as the impurity profiles of proposed generic drug products and the Reference Listed Drugs (RLDs). In addition, in the stability testing of the generic drug and the RLD, the impurity profile of the generic drug is required to be consistent with that of the RLD. Based on the importance of comparative study of impurity profiles in consistency evaluation, Alfa Chemistry analyzes the impurity profiles in detail to identify the structure and source of potential impurities with full consideration of the process route, degradation pathway, excipients and other raw materials.

Figure 1. Qualification of impurities in the drug. (Weidolf, L.; et al. 2019)

Strategies for Comparison of Impurity Profiles

At Alfa Chemistry, a variety of advanced separation techniques (such as HPLC, UPLC), mass spectrometry (or diode array detection) are available to identify and quantify differences in the impurity profiles of your generic product and the RLD from information such as chromatographic behavior, UV characteristics, molecular weight and molecular fragment characteristics.

We provide a series of comparative study for the following impurity profiles:

• Impurity profiles of generic drugs and the RLD through making a comparison of retention time
• Impurity profiles of generic drugs and the RLD by investigating the changes in the impurity profile after accelerated stability testing
• Impurity profiles of APIs and excipients

Structural Confirmation of Impurity

• Provide structural information of impurities (such as the parent chain, some specific side chain, etc.)
• Identification of the sources of impurities
• Determination and identification of different components in the generic drug after completing the accurate comparison of impurity profiles

Impurity Analysis Service

Comparison and analysis of type, content and distribution of impurity to determine:

• Whether there are unknown impurities in the generic drug that are not in the RLD product
• Whether there are observed impurity levels exceed the level observed in the RLD product
• Whether there are new impurities are introduced after the manufacturing process of generic drug is changed
• The classification of impurities, such as degraded impurities (confirm the degradation pathway), impurities in excipients, process-related impurities, etc.

Features of Our Services

• Consistency of the detection method used with the standard method
• Our well-developed method has good specificity, high sensitivity and high reproducibility, which can fully detect related impurities
• Provide enough data by performing comparative analysis of multiple batches of samples