PHARMACEUTICALS of viable synthetic processes and practical steps make adoption feasible, despite common hurdles. Risk drops when teams start with a single pain-point step, set clear performance metrics and work with external partners in a joint design model.
This is where an integrated CDMO or CRO partner can be particularly valuable, especially for small biotechs. Rather than building a flow capability from scratch, companies can access existing infrastructure immediately, including laboratory screening platforms, pilot-scale flow systems, photochemical and electrochemical equipment, PAT tools and engineering support. This removes much of the upfront capital burden and allows development to start on proven platforms rather than waiting for internal setup.
Reactor manufacturing capability on demand can be a decisive differentiator. A capable partner can often adapt, configure or oversee fabrication of fit-for-purpose flow reactors and ancillary hardware to match the chemistry, rather than forcing the chemistry into an unsuitable standard set-up. For small biotechs, this access to customised reactor set-ups without the need to build internal engineering resources can make the difference between flow remaining a theoretical option and becoming a practical development route.
Case study
By combining early process assessment, thoughtful reactor selection, established flow infrastructure and the engineering expertise required for rapid development and scale-up, Thermo Fisher Scientific’ s flow group in Austria delivered a compelling demonstration of how flow chemistry can shorten the path from process concept to commercial antibacterial manufacture.
The Matteson reaction was used to prepare a key intermediate for an antibiotic. Conventional batch scale-up was not an option because the transformation involved cryogenic organolithium chemistry and a labile intermediate. The team instead had to translate the step into continuous flow, optimise it through pilot operation and subsequently implemented a custom productionscale reactor, followed by a fully continuous loop-reactor quench.
This intensified process improved productivity, energy-efficiency and waste performance while delivering robust cGMP output at high purity and yield. This resulted in the drug’ s FDA approval in 2017 and the underlying product achieved market authorisation on a highly accelerated timeline.
External partnerships with companies experienced in continuous processing accelerate progress. The strongest collaborations treat route design, solvent strategy, reuse plans and quality control as a unified effort, avoiding fragmented hand-offs that amplify risk.
Outlook
As development timelines tighten and cost pressure on pharmaceutical products continues to increase, modular flow concepts are becoming increasingly valuable because they combine speed, flexibility and sustainability on a single development platform. Standardised modules for reaction, mixing, quench, photochemistry, electrochemistry, crystallisation, slurry milling, drying and inline analysis can be deployed and reconfigured rapidly, reducing development time, limiting implementation risk and allowing processes to be adapted more efficiently across development stages.
This is particularly relevant for photo- and electrochemical processing. Under flow conditions, short optical path lengths, uniform irradiation and narrow-gap electrochemical cells enable the efficient use of photons and electrons as reaction-driving tools.
In this way, flow chemistry makes it increasingly feasible to replace stoichiometric oxidants or reductants with cleaner activation modes, reducing reagent consumption, waste generation and often also purification burden. At the same time, extending the continuous concept beyond reaction into downstream operations such as crystallisation, slurry milling and drying creates a more integrated manufacturing strategy, improving control over particle properties, reducing hold times and supporting more consistent product quality. Looking ahead, modular flow technologies are likely to become an important element of future API manufacturing strategies, especially where sustainability must be delivered without compromising speed, robustness or economic competitiveness. Combined with the broader application of the remaining ACS green chemistry principles, and with continuous downstream processing concepts, flow chemistry is therefore well positioned to contribute substantially to the next generation of more sustainable API manufacturing. ●
J j
Axel Zimmermann
DIRECTOR, PROCESS DEVELOPMENT SERVICES
THERMO FISHER SCIENTIFIC axel. zimmermann @ thermofisher. com www. thermofisher. com
MAY / JUN 2026 SPECCHEMONLINE. COM
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