When we reach for a paracetamol to ease a headache or take a course of antibiotics to treat a throat infection, few of us would have any notion of the role played by chemical engineers in bringing these little pills to our bathroom cabinets. Unlike their contribution to oil refining, chemical manufacture or waste water treatment, widely acknowledged and celebrated, the role played by chemical engineers in the mass production of pharmaceuticals is largely unknown. However, without the skills of the chemical engineer, applied to the production of pharmaceuticals to ensure the drugs discovered can be produced in the quantities required, millions of us would have died from simple infections.
Fleming, Florey and Chain are rightly remembered as the fathers of penicillin, but without the respective contributions of industrial chemist and engineer Jasper Kane and John McKeen, both working for Pfizer around the first half of the 20th Century, penicillin might have remained a laboratory curiosity, available only to a few. Even then, the first patient to be treated died when Florey couldn't extract enough penicillin from his petri dishes to stem an infection. Kane and McKeen moved penicillin off the laboratory bench and into industrial-scale production via deep-tank fermentation, allowing the timely treatment of hundreds of thousands of people by the end of the second world war.
Since the early 20th Century, chemical engineers have been applying their knowledge of chemistry and processes to upscale the production of medicines and medical gases, underpinning the rapid increase in average life expectancy of wealthy countries. Engineers have been behind the success of companies such as GSK, AstraZeneca, and Pfizer for over 50 years.
Driving the health and wealth of nations
The 1900s was the golden age of drug development, and like many industries, advancements were accelerated by war, where the power of disease is often more destructive than the clash of armed forces; diseases such as typhus, plague, dysentery and malaria have often decided the course of a campaign.
As Australia fought its own battles in the Pacific, chemical engineers were instrumental in repurposing a Monsanto chemical facility to quickly produce the sulpha drug, sulphaguanidine, effective against dysentery. By 1942 production had increased in to meet the demands of the British forces in Burma and India.
Just as medicines are a fairly recent addition to our bathrooms, so too are medical gases in hospitals. Early health care could do little for a patient struggling to breathe. Chemical engineers have been critical in facilitating the supply of medical gases through the development of a cryogenic process to separate oxygen at any scale, from the development of the distribution process for small bottles for personal use to bulk tankers for hospitals. They have also given us the helium and nitrogen required to operate MRI scanners.
The evolution of the pharmaceutical industry
The pace of science and engineering knowhow – unhindered by practical patient outcomes, regulation and mass production – often outsteps industry, which prioritises patient safety and regulatory oversight over speed. Since the bourgeoning of prescription drugs from the 1950s onwards, big pharma recorded annual sales exceeding US $1trillion in 2020. These impressive heath and economic outcomes have only been made possible by chemical and biochemical engineers, who, along with biologists, biochemists, pharmacists and geneticists, have specified and designed manufacturing, processing, instrumentation and control systems. Engineers understand the key quality-related manufacturing requirements to ensure facilities will meet regulatory requirements.
Pharmaceuticals are often complex and costly to make. Chemical engineers ‘de-bottleneck’ and ‘process intensify’ to improve efficiencies and reduce cost, while ensuring safe manufacture with minimal environmental impact.
Covid-19 has shown that when scientists, engineers, regulatory bodies and governments all work together, the pharmaceutical industry can be agile and respond rapidly to achieve great outcomes.
The pandemic has required an unprecedented response to enable the development, manufacture and regulatory approval of vaccines, without compromising on safety and efficacy standards. Through the financial backing of governments and public institutions, which lightened the risk burden for companies developing vaccines, progress was prioritised, and a rolling review of data, as soon as it became available, allowed a timely response from regulators.
Across the globe, chemical engineers have also responded to the pandemic through vaccine development, applying their skills to build and design emergency ventilators and developing rapid antigen tests.
Pharmaceutical manufacture currently finds itself at a crossroads as it faces continual challenges to intellectual property rights and licencing, questions around equitable access, and sustainability, and a technological/scientific paradigm shift bringing pharmacy and biotechnology closer together. As pharmaceuticals change from traditional small molecules to more complex biologics and stem cell therapies, chemical engineers are shifting their focus towards these biological fields. As these products grow, more chemical engineers will be required to drive the changes at an industry level to meet future healthcare challenges, including processes that are small scale, agile and flexible to address the production of novel compounds at speed – increasingly important for the treatment of diseases.
To address these issues chemical engineers will need to apply their knowledge to continuous processes, which is familiar territory. By looking at thermodynamics, kinetics and choosing the right reactor systems, rather than scaling up laboratory processes, they will provide the way forward with technologies that require less solvent, improved yields and thereby reduced capital cost.
A healthy, sustainable and equitable future
The pandemic has revealed many truths regarding global health care, most particularly, highlighting the home grown advantage. In Europe and the United States there is a significant effort to move the production of generic brand pharmaceuticals back to home-countries. However, there are many constraints to bringing offshore registered manufacturing sites home quickly, the largest one being the process of regulation. A modular continuous facility, fitting into one or several containers, is one possible solution. The containers themselves become approved mini manufacturing units, and once approved, can be relocated and installed where they are needed most merely by connecting to raw utilities and effluent systems.
The roles of future chemical engineers in advancing health care are many and varied. From ensuring safe, efficient and sustainable methods of production, to working with researchers on the new frontiers of personalised medicine, for example sensors and biological markers to monitor addiction. Problem solving at the interface of biology, chemistry and engineering offers exciting and inspired opportunities for young engineers to meet the challenges of global health care in next decades.