S.5002, a bill “To allow for alternatives to animal testing for purposes of drug and biological product applications”, entitled FDA Modernization Act 2.0, was considered, and passed the U.S. Senate 29th September 2022. In June 2022, the U.S. House of Representatives passed the FDA legislative package, the H.R.7667 measure, which included the original version of “FDA Modernization Act of 2021”, introduced in April 2021 as H.R.2565 bill. On December 23rd, 2022, the U.S. House of Representatives gave its final approval to the FDA Modernization Act 2.0. President Biden signed the FDA Modernization Act 2.0 into law December 29th, 2022.
Specifically, Section 505, subsection (i), paragraphs (1)(A) and (2)(B) of the Federal Food, Drug, and Cosmetic Act (21 U.S.C. 355) were amended by replacing the “preclinical tests (including tests on animals)” and “animal” with the term “nonclinical tests”.
The term ‘nonclinical test’ means a test conducted in vitro, in silico, or in chemico, or a non-human in vivo test that occurs before or during the clinical trial phase of the investigation of the safety and effectiveness of a drug, and may include animal tests, or non-animal or human biology-based test methods, such as cell-based assays, microphysiological systems, or bioprinted or computer models.
Spheroid, organoid, and organ-on-a-chip are three dimensional (3D) in vitro cell-based systems that bridge the gap between “cells on plastic”, a standard 2D cell culture, and the in vivo animal models. Spheroids and organoids are also referred to as artificial microtissues (e.g., heart, lungs, liver, etc.), whereas the organ-on-a-chip (or microphysiological system) is the artificial microtissue super-structure containing several microtissues linked together like in a living organism (in vivo). The complexity of the system influences the throughput of testing. Thus, organ-on-a-chip is a low scale, low volume, and low throughput.
Typically, artificial microtissues (spheroids and organoids) are designed by reaggregation of dispersed human primary cells and maintain tissue-specific functionality and/or provide complex feeder constructs enabling the differentiation of cell types unable to undergo this process in 2D environment. Importantly, spheroid and organoid artificial tissues allow phenotype-modulating and therapeutic interventions in a high-throughput manner, which is not possible in vivo. The resulting kinetics of drug candidate-function correlation offers unprecedented acceleration of current drug discovery programs.
In a video recorded by the researchers from the University Zurich, Switzerland, the superstructures of artificial myocardial microtissues (myocardial spheroids) are beating/contracting in unison (Kelm et al., 2004). Even though, the reaggregated cells of these spheroids have a rodent origin, similar artificial microtissues are possible to design using primary human cells or human induced pluripotent stem cells. Remarkably, these cells can be taken from a patient to fine-tune drug/drugs combination, which is optimal for this patient.
Currently, INFRAFRONTIER, the European Research Infrastructure for phenotyping and archiving of rodent models, provides the access to ~2200 mouse strains related to ~1600 distinct rare diseases (a disease afflicting less than 1 in 2000 individuals). However, there are ~7000 rare diseases and in Europe alone ~30 million people are suffering from a rare disease. Importantly, mouse rare disease models are surrogates for human rare disease models. Thus, there is a huge potential for human artificial microtissue- and organ-on-a-chip-based rare disease model platforms for drug discovery.
FDA Modernization Act 2.0 does not ban the animal testing, rather it allows drug developers to use alternatives when it is deemed feasible. Drug developers no longer have to use animal models before or during the clinical trial phase of the investigation of the safety and effectiveness of a drug.
There are still many challenges to overcome to enable the usage of spheroids and organoids in high-throughput assays. The reproducibility and scalability are among the most pressing ones.
To solve these challenges, NextGenRnD OÜ created novel platform technology (TRL 2/3) that should enable direct measurement of pressure generated by airway smooth muscle (ASM) (lung) spheroid during contraction in high throughput format (e.g., healthy vs. asthmatic spheroids). This platform should allow quantitative and real-time analysis of contraction and dilation of ASM spheroids in non-invasive manner.
Experimental steps required for the ASM contraction sensor platform validation, experimental plan, and feasibility analysis are available. In addition, high-throughput approaches for identification of novel potential targets for asthma treatment are described (both biological and chemical). The ASM spheroid contraction sensor platform should assist in revealing the following major functional differences between healthy and asthmatic ASMs: overall microtissue structural organization; contraction pressure; and contraction/relaxation rapidity. The contraction sensor platform is universal and can be leveraged for myocardial spheroids with minor changes.
Contact NextGenRnD OÜ if you are interested in details of our contraction sensor platform technology.