The FDA is Changing the Rules of Preclinical Testing. Here’s Why Patient-Based Ex Vivo Assays Matter
In recent years the FDA has taken significant steps toward reducing the reliance on animal testing in drug development. Through the endorsement of New Approach Methodologies (NAMs) the agency is encouraging the use of human-relevant models that can offer faster, safer and more predictive insights into drug safety and efficacy.
This regulatory shift is not only about ethics. It reflects a scientific consensus that traditional animal models often fail to capture key aspects of human biology. In fact more than 90 percent of drugs that succeed in animal studies ultimately fail in human clinical trials.
What Are NAMs
The FDA defines NAMs as innovative technologies and approaches that can serve as full or partial replacements for animal studies. These include:
- Organ-on-chip systems that recreate physiological functions using human cells under controlled conditions
- In silico models powered by artificial intelligence to simulate drug behavior and toxicity
- Advanced in vitro cultures such as organoids or multi-cell co-cultures
- Ex vivo assays performed on human tissues or samples that preserve native biological conditions
Each of these options contributes differently to the future of preclinical testing. Among them, ex vivo assays using patient samples stand out for their ability to combine real biological complexity with functional relevance.
The Value of Ex Vivo Testing in Patient Samples
Ex vivo assays allow researchers to study drug effects in real human tissues directly removed from the clinical setting. When designed to preserve the native environment of the cells, these assays offer several advantages:
- Directly reflect human pathophysiology, avoiding species-specific artifacts
- Maintain the full cellular diversity and architecture of the original tissue
- Capture patient-to-patient variability and identify responders early
- Generate meaningful data on functional endpoints such as cytotoxicity, immune activation, and resistance mechanisms
These features make patient-based ex vivo assays highly valuable not only in drug discovery but also in biomarker validation and translational research.
Vivia Biotech. Two Decades at the Forefront
Vivia Biotech has been developing and delivering ex vivo assays using native patient samples for over 20 years. Our platform combines multiparametric flow cytometry with whole-sample preservation to offer unmatched biological realism.
We have analyzed over 10,000 patient samples and profiled more than 700 drug candidates across hematologic malignancies, solid tumors, and autoimmune diseases. Our proprietary assays preserve the full cellular microenvironment allowing us to evaluate drug activity in real conditions, including immune–tumor–stroma interactions.
Our studies have supported early decision-making, candidate selection, biomarker development, and patient stratification strategies for clients ranging from emerging biotechs to global pharmaceutical companies.
As the FDA promotes a shift toward faster, safer, and more predictive preclinical models, Vivia’s ex vivo platform stands as a proven functional NAM. It is ready to be integrated into modern development programs that demand human relevance from the start.