The container a drug product lives in has always mattered, but as biologics and gene therapies push the limits of sensitivity and complexity, it matters a great deal more. Matt Wills has spent over a decade at the intersection of material science and primary packaging, and in this episode he breaks down what is actually happening at the drug contact surface — and why that surface, not the bulk material, is where the real compatibility story plays out. He explains why glass is hitting its limits with certain advanced formulations, what is lost and gained in a switch to plastic, and how PECVD-based coating technology is opening up a third option that was not on the table a decade ago.
The conversation goes well beyond material selection. Matt walks through how siliconisation introduces risk that teams often underestimate, why container closure integrity failures are rarely a single-component problem, and why the weakest link in a syringe system is so often the interface between components rather than any component in isolation. He also introduces the concept of maintaining a common drug contact surface across the entire manufacturing chain — from API storage through to the final filled container — and what that approach could mean for bridging studies, regulatory validation, and the speed at which programmes can progress.
Key takeaways:
The drug contact surface is the critical parameter in container selection, not the bulk material — glass, plastic, and hybrid containers all behave differently at that surface layer, and understanding the mechanism of interaction is what drives root cause investigations
Glass remains robust and well-characterised, but faces real limitations at high pH (risk of delamination), in complex formulations, and in design flexibility for combination product integration
Plastic offers more design freedom and better compatibility with auto injectors and on-body devices, but introduces trade-offs including oxygen barrier performance and different CCI behaviour at cold storage temperatures
PECVD-based coatings (such as SiO2's technology) allow the drug contact surface to be engineered independently of the bulk container, combining glass-like inertness with the design flexibility of plastic — but regulatory data, while growing, is still newer than glass
Siliconisation solves a real engineering problem but introduces its own risk profile; the question is not whether silicone oil is harmful, but whether its interaction with a specific molecule is acceptable and controllable — and whether an alternative lubrication system might be easier to design around.
Container closure integrity is a pass-fail requirement, not a nice-to-have — Teflon-coated plungers can compromise CCI at cold storage conditions due to differential shrinkage rates, and this needs to be understood before committing to a system
The syringe is a multi-component system, not a single unit — plunger, barrel, siliconisation, needle geometry, and luer design all interact, and optimising components in isolation without understanding their interfaces is where programmes run into trouble
Maintaining a common drug contact surface across the full manufacturing chain (API storage, processing, final container) can reduce validation unknowns, support bridging arguments, and shift the focus from reproving drug-surface interaction to proving like-for-like equivalence between container sizes.
Connect with Matt Wills on LinkedIn: https://www.linkedin.com/in/mattswills/
Visit SiO2 Materials Science: https://sio2med.com/
Subscribe to Navigating the Combination for more conversations on primary packaging, drug-device integration, and the science behind combination product development.
I hope you enjoy this episode! Give it a like, share, and subscribe to not miss the content coming your way weekly.
– Parth & Jonathan and the Navigating the Combination podcast team
Connect with Parth Kothari on LinkedIn: https://www.linkedin.com/in/parthjkothari/ Connect with Jonathan Amaya-Hodges on LinkedIn: https://www.linkedin.com/in/jonathanwhodges/ Visit the Suttons Creek website here: https://suttonscreek.com
Listen to Navigating the Combination on these podcast platforms:
Spotify: https://open.spotify.com/show/033HRTwEj7aFLx9K8ZEsVG
Apple Podcasts: https://podcasts.apple.com/us/podcast/navigating-the-combination/id6786238670
Amazon Podcasts: https://music.amazon.com/podcasts/12169e2d-2323-41db-bdb4-8a8e7841c799
#navigatingthecombination #suttonscreek #combinationproducts #drugdelivery #pharmaconsulting #regulatoryaffairs #medicaldevices #biotech #pharmabiotech #fdaregulation #drugdevicedevelopment #lifesciences #combinationproductdevelopment #pharmapodcast #devicestrategy
Navigating the Combination is the podcast for pharmaceutical and biotech professionals tackling one of the industry's most complex challenges: bringing drug-device combination products to market. Hosted by Parth Kothari and Jonathan Amaya-Hodges of Suttons Creek - the device team for pharma - each episode draws on 650+ combined years of experience and 120+ successful launches to cut through the complexity of combination product development, from device selection and regulatory strategy to OEM alignment, quality systems, and FDA submissions.
Whether you're a VP of Regulatory Affairs weighing your submission strategy, a program director managing a complex OEM relationship, or an executive trying to protect a multi-million-dollar drug investment, this podcast gives you the insight, clarity, and confidence to make the right calls - right the first time.
