In-Vitro (IVRT/IVPT) Studies
In-vitro assessment of topical products — solutions, foams, sprays, creams, gels, lotions and ointments — is a critical part of drug development, supporting new chemical entity selection, prototype formulation optimization, and bioequivalence demonstration for generics.
DALPL's Pharma Testing Division designs, develops and validates In-Vitro Release Test (IVRT) and In-Vitro Permeation Test (IVPT) studies aligned to current US FDA and EMA expectations, including EMA's finalized guideline on quality and equivalence of locally applied, locally acting cutaneous products.
The Regulatory Pathway
For appropriate topical and locally applied products, equivalence assessment can progress through a structured sequence of pharmaceutical equivalence, in-vitro assessment and, where necessary, pharmacodynamic or clinical studies.
Pharmaceutical Equivalence
Formulation sameness
Establish pharmaceutical equivalence between the test and reference formulations as the foundation for comparative assessment.
In-Vitro Assessment
In-vitro release / permeation assessment
Use IVRT/IVPT studies to characterize comparative release and permeation behaviour of topical formulations.
Pharmacodynamic or Clinical Studies
Where additional evidence is required
Pharmacodynamic or clinical studies may be required where Steps 1–2 are not sufficient to establish equivalence.
Our IVRT/IVPT Study Services
DALPL provides method development, validation and comparative study support for topical products across release, permeation and supporting product-characterization requirements.
In-Vitro Release Testing (IVRT)
Compare the rate and extent of active substance release between test and reference topical formulations, using diffusion cells under pseudo-infinite dosing. The method can discriminate formulations with altered critical quality attributes.
In-Vitro Permeation Testing (IVPT)
Use ex-vivo human skin in conjunction with Franz vertical diffusion cells to establish characteristic permeation profiles for dermal pharmacokinetic assessment.
Supporting Characterization
Supporting characterization may include:
- Rheology & Viscosity
- Microscopic characteristics
- Release rate
- Particle size
- Oil droplet size distribution
Method Development & Validation
Method development and method validation covering sensitivity, specificity and selectivity, together with pivotal comparative study execution.
IVRT and IVPT: Complementary In-Vitro Assessments
IVRT
IVRT focuses on the release of the active substance from a topical formulation and enables comparison of release rate and extent between test and reference products.
IVPT
IVPT evaluates permeation through ex-vivo human skin using Franz vertical diffusion cells and establishes characteristic permeation profiles relevant to dermal pharmacokinetic assessment.
Supporting Product Characteristics: Product characteristics such as rheology, viscosity, microscopic characteristics, particle size and oil droplet size distribution can provide additional context when developing and comparing topical formulations.
Topical Product Types
The IVRT/IVPT service applies to topical products including:
Why DALPL
Delivering high-accuracy impurity profiling with uncompromised regulatory integrity.
From Formulation Development to Bioequivalence Assessment
IVRT/IVPT studies can form part of a structured development and equivalence strategy for appropriate topical products.
Define the Product
Understand the topical formulation and its relevant critical quality attributes.
Develop the Study Method
Establish the appropriate IVRT/IVPT approach and supporting characterization requirements.
Validate the Method
Evaluate method performance through relevant sensitivity, specificity and selectivity considerations.
Compare Test and Reference
Execute the comparative study to assess release and/or permeation behaviour.
Support Equivalence Assessment
Use the resulting evidence as part of the broader bioequivalence or product-development strategy where applicable.
Frequently Asked Questions
Explore Related Testing Services
Get an IVRT/IVPT Testing Quote
Speak with our Pharma Testing team about your topical product, IVRT/IVPT study requirements and bioequivalence assessment strategy.