- Last year, the U.S. government passed the Food and Drug Administration Modernization Act 2.0.
- The move is expected to boost the research and development of ‘organ chips’ — small devices containing human cells that are used to mimic the environment in human organs, including blood flow and breathing movements, serving as synthetic environments in which to test new drugs.
Introducing a new drug
- Bringing a new drug into the market is an expensive process ridden with failure. First, researchers identify chemical compounds that can be used to treat a condition using modelling and other techniques.
- Then they shortlist those that perform well and test them on cells grown on plastic dishes in the lab or on animals that can mimic the disease in certain conditions.
- At this stage, called the preclinical trial, scientists determine whether these drugs are toxic and if they can efficaciously treat the condition.
- Animals used here include mice, rats, hamsters, and guinea pigs, depending on the drug being tested. Researchers also use pigs when testing implant devices like stents. If the trial results are favourable, researchers can begin human clinical trials.
- Today, fewer than 10% of new drugs complete preclinical studies and fewer than 50% of these eventually successfully complete clinical trials.
- Some researchers blame the use of animal models in preclinical studies for this enormous failure rate. The current consensus is that animals can mimic some human diseases well but not others.
- In cases where they can’t, a new drug that seems promising in preclinical studies is almost certainly bound to fail in human clinical trials.
- These challenges have led scientists to look for alternative models that mimic human diseases. One such is the organ-on-a-chip model, which has garnered a lot of attention in the last decade.
- Donald Ingber, a professor of bioengineering and director of the Wyss Institute at Harvard University, and his colleagues developed the first human organ-on-a-chip model in 2010. It was a ‘lung on a chip’ that mimicked biochemical aspects of the lung and its breathing motions.
- In 2014, Wyss Institute members launched a startup called Emulate Inc. to commercialise their technology.
- The group has since created several different chips, including of the bone marrow, epithelial barrier, lung, gut, kidney, and vagina.
- Recently, Emulate’s liver chips could successfully predict the ability of drugs to cause liver injury with 87% sensitivity and 100% specificity.
- The researchers used liver chips to evaluate the toxic effects of 27 drugs known to be either safe or cause liver injury in humans.
Organ chips in India
- Some of these organs-on-chips that Indian scientists have developed are ready for use as drug test-beds in lab settings, but they could be a decade away from featuring in preclinical trials, with a push.
- Researchers and biomedical companies in the West have started to build larger human-on-chip models — assemblies of different organ chips containing nutrients for the cells flowing across them, mimicking the flow of blood and nutrients across different organs in the body.
- The idea is to predict the efficacy of a drug against a particular disease in the presence of messy organ interactions instead of cleanly isolated systems.
SOURCE: THE HINDU, THE ECONOMIC TIMES, PIB