Both physical and structural properties of a person can influence the API or Active Pharmaceutical Ingredient release rate in all the semisolid drug topical formulations. Measurement of the API is exceptionally critical throughout the development of the drug lifecycle and the processes. It begins from the initial phase of the selection of clinical candidates till the setting of the specifications in the late developmental segment. It also includes changes or modifications in the products and post-approval QC. In the topical formulations of the semi-solid drugs, In-Vitro Release Testing or IVRT is becoming a more vital and prevalent tool for determining the API diffusion and the release rate in the topical products.
Explanation of the IVRT process
During the drug development lifecycle and process, dissolution testing detects the physical changes in the drug formulation and the API, necessary for all oral solid dosages. Similarly, for the non-oral doses, including the topical formulations of the semi-solid drugs, in-vitro testing is required for evaluating the properties in the drug releases. IVRT measures the drug release rate by implementing the Franz diffusion cells and a non-interactive synthetic skin or membrane and is used for developing the methods. It analyzes the various ranges of semi-solid dosages, which include:
- Creams
- Lotions
- Suspensions
- Ethosomes or Liposomes
- Ointments
- Hydrogels
- Topical Aerosols
- Microencapsulation
IVRT Guidance and Testing
FDA has already released the guidance for the post-approval and scale-up guidance of the industry. IVRT identifies the non-sterile semi-solid dosage forms with the intended topical administration route, which might include:
Change in the levels
CMC level to support every change level
Suggested IVRT or in vivo bioequivalence tests to support every change level
Documentation supporting the change
Lately, FDA has published a different guideline to overcome various barriers for the generic medicines developers and enhancing patient care. These strict and clear instructions assist the industry with BE or Bioequivalence assessments, implementing the IVRT methods in the clinical studies.
