Dr Stephen Dalby

Process chemistry involves developing chemical syntheses (processes) which can be run safely and reliably at a manufacturing scale to deliver active pharmaceutical ingredients (APIs), meeting regulatory specifications in sufficient quantity to ensure clinical supply for the patient population.

Process chemists have a responsibility to design processes that are environmentally conscious, minimise raw material consumption, waste generation and the use of hazardous or toxic chemicals. In so doing, the sustainability of manufacturing is assured and costs are driven down which may be relayed to the patient, broadening the accessibility and societal impact of new medicines.

Finding simple, green and sustainable solutions to synthetic chemistry problems is challenging, however, and often requires pushing the boundaries of the science through the invention of new methods. For example, for the anticancer agent Belzutifan, Stephen and his team discovered a way to carry out a reaction using simply visible light, which avoided the use of hazardous chemical reactants and chlorinated solvent. This solution represents the first example of such a photochemical reaction at MSD, and required innovative reaction engineering and equipment build to enable commercial production. This now paves the way for future processes to exploit light as a renewable means of carrying out chemical reactions, further advancing green and sustainable process capabilities.