Study finds a more sustainable way to develop pharmaceuticals

University of Bath’s chemistry researchers recently devised a novel process utilizing blue light to develop pharmaceuticals in sustainable means, substantially decreasing the amount of energy required and the chemical waste produced during the manufacturing process.

The reaction uses a catalyst activated with blue LED light. Image Credit: Dr Alex Cresswell.

There are many steps involved normally in the synthesis of small-molecule drugs—and each step generates waste products and solvent waste that are toxic and hard to dispose of securely.

It is evaluated at present that for each kilogram of drug produced, around 100 kg of waste is generated, which makes it a greatly incompetent process.

The researchers from Bath, headed by Dr. Alex Cresswell, a Royal Society University Research Fellow in the University’s Department of Chemistry, identified a novel means of producing nitrogen-containing chemicals known as primary amines—employed in numerous pharmaceuticals.

The process employs a catalyst that is activated by blue light to boost the reaction. It uses less energy, fewer steps, and drastically decreased the waste generated by drug development.

The researchers checked the process by synthesising a drug used for multiple sclerosis (MS)—Fingolimod (brand name Gilenya)—developed by Novartis and had a global sale of $3 billion in 2020.

The study was published in the Journal of the American Chemical Society (JACS).

Making pharmaceuticals can be a wasteful process, with most of that waste being incinerated. Our new process synthesises α-trisubstituted primary amines using only one step, a goal that has eluded chemists for many years. People don’t really think about the pharmaceutical industry when it comes to carbon emissions, but some studies have calculated that big pharma emits more than the automotive industry.”

Dr Alex Cresswell, Department of Chemistry, University of Bath

“We’re really excited that our group is the first in the world to achieve this breakthrough, and hope that it could in the future lead to much more sustainable pharmaceutical manufacturing processes,” added Dr Cresswell.

Even though the current process is not likely to be accepted right away by pharmaceutical companies for mass production of existing drugs, the researchers expect that the process would boost drug discovery and development. This is because the new method makes it easier to synthesize new chemical structures for testing.

Building new molecules during the drug discovery process requires reactions that make it simple to ‘click’ atoms together in the required way, a bit like building models out of Lego. The aim is to make thousands of different derivatives for biological testing, and our new process gives chemists a way to connect certain atoms that simply wasn’t available before. This should help to speed up the discovery process.”

Dr Alex Cresswell, Department of Chemistry, University of Bath

The researchers are associating with various pharmaceutical companies to expand the process.