Animal testing has long been necessary for a drug to gain approval from the FDA. However, in recent years, the method has raised concerns. Animal models, while similar to humans, aren’t similar enough to serve as an accurate test for more complex diseases like neurological diseases.

In the past, animal testing has also proven to be an unreliable predictor of how a drug will behave in humans. In fact, an estimated 90% of drug candidates that fare well when tested on animals fail once clinical trials begin. This is why FDA approval of an emerging technology called organs-on-chips (OOCs) provides a new method that could revolutionize the way drugs are tested.

OOCs are small devices that are about the size of a flash drive. These chips contain a certain kind of human cell and push fluid through small channels to mimic the blood flow and activity of a particular organ. The contents of the chip can be manipulated to mimic the behavior of an organ that has been affected by a disease. For example, scientists can create a chip to mimic a normal pancreas and then change different aspects of the chip so that it reflects the behavior of a cancerous pancreas.

The first OOC was created in 2010 as a lung model. The device was able to carry out basic functions of a lung including the exchange of oxygen and carbon dioxide. In January of 2023, the FDA approved the usage of OOCs to test drugs, providing an alternative to animal testing.

In the past year, researchers at Harvard used OOCs to develop a drug to treat COVID-19. OOCs proved more effective than animal testing because scientists were provided with immediate and accurate feedback that pertained to humans. This allowed them to make adjustments quickly and send the drug into a clinical trial in under two years.

OOCs have shown potential when it comes to drugs used to treat liver diseases. Typically mice tend to be the test subjects for newly developed drugs. However, one key difference between mice and humans is how proteins bind within the liver. This meant that no negative side effects were seen when drugs for liver diseases were tested in mice. However, once the drug was given to humans, toxic compounds were given off that damaged the liver. Using OOCs, scientists can create a physiological environment that matches the human liver, which will speed up drug development and make the process cheaper.

While OOCs can’t give scientists a complete picture of a drug’s potential to do harm, especially when considering possible long-term impacts, they have the potential to speed up drug development and provide a testing environment that is physiologically similar to the human body. In addition, by making the process shorter and more accurate, life-saving drugs can become cheaper and more accessible for those who need them.