Summary
Pharmaceutical manufacturing is changing. Discover how functional excipients can support your transition to continuous manufacturing. In particular, twin-screw granulation (TSG) is redefining how binders must perform in tightly controlled process conditions.
For years, batch processing was the standard in solid dosage production. It is well understood and reliable. But today, more companies are moving towards continuous manufacturing including twin-screw granulation. This shift is not only about new equipment. It changes how we think about formulation. Especially when it comes to excipients.
In this article we explore:
- How twin-screw granulation in continuous manufacturing is raising the bar
- Why binders must work differently in continuous systems
- Flow and stability are no longer optional
- Patient-centric design starts with excipient choice
- Multifunctional excipients can reduce formulation complexity
Twin-screw granulation is gaining ground
Twin-screw granulation is a continuous wet granulation process in which powders are mixed and granulated within an extruder equipped with two intermeshing screws. The process typically involves residence times of only a few seconds, requiring excipients to activate rapidly and predictably. This process allows powders to be processed continuously instead of step by step in batches. That brings several advantages:
- Smaller production footprint
- Better process control
- Faster scale-up
- More consistent product quality
Regulators are encouraging this move, but there is a catch. Continuous manufacturing is less forgiving. Materials must perform consistently from the first minute to the last.
Excipients in the spotlight: What modern granulation really demands from binders
In batch processing, there is often more room to adjust. In continuous systems, shear forces, torque stability and liquid-to-solid ratios must remain within a narrow operating window. Small variations in binder activation can directly influence granule density, friability and downstream compressibility. Therefore, binders need to do their job quickly and predictably. That means:
Fast and controlled solubility: The binder must activate rapidly, but not too aggressively. Too much liquid can disturb the process. Too little can lead to weak granules.
Reliable flow behaviour: Continuous feeding depends on smooth powder flow. Any inconsistency can disrupt the line.
Process stability: Temperature and mechanical stress can be higher in continuous systems. Excipients must remain stable and robust.
Patient-friendly properties: Today, formulation is not only about manufacturability. Taste, mouthfeel and acceptability matter more than ever, especially in chewable and orally disintegrating formats.
Continuous manufacturing forces us to rethink excipients. We need materials that support the process, not challenge it. That requires a much deeper understanding of functionality.
Dr Maj-Britt Cepok,
Head of Pharma at BENEO
The new perspective on excipients
For a long time, excipients were often seen as secondary components. In modern manufacturing, however, they are performance drivers.
The right excipient can:
- Stabilise the process
- Simplify formulation
- Improve product quality
- Enhance patient experience
This is where galenIQ™ (pharmaceutical grade Isomalt) is gaining attention. The combination of solubility, stability and taste profile makes it a well-suited option for continuous granulation
Some advantages are:
- High water solubility
- Good flow properties
- Thermal stability
- A sweet taste profile
Rather than being used only as fillers, galenIQ™ can take on multifunctional roles in the formulation. Its crystalline structure and defined solubility profile can support controlled moisture distribution during granulation, contributing to reproducible granule formation under short residence times.
In continuous systems, multifunctionality becomes a real advantage. If one material can contribute to binding, stability and patient acceptability, that reduces complexity.
Oliver Luhn,
Head of Pharmaceutical Technology at Südzucker AG
Knowledge exchange driving continuous innovation
Innovation needs collaboration
The transition to continuous manufacturing is not happening in isolation. It is driven by close collaboration between industry and academia. The growing regulatory acceptance of continuous manufacturing, reflected for example in ICH Q13 guidelines (an international regulatory guideline that focuses on continuous manufacturing of pharmaceutical products), further underlines the importance of robust excipient functionality.
Through international research networks and scientific partnerships, BENEO’s pharmaceutical team actively contributes to the discussion around excipient functionality and process optimisation. This exchange ensures that development is based on real manufacturing challenges, not theoretical assumptions.
“Innovation in granulation does not happen behind closed doors. It happens through dialogue. By working closely with academic partners and industry experts, we gain insights that directly translate into better solutions.”, says Oliver Luhn, emphasising the importance of this ecosystem.
Such networks are essential to move from promising theory to practical implementation.
Continuing the conversation between academia and industry
The growing interest in twin-screw granulation shows that continuous manufacturing is not a passing trend. It is becoming part of the pharmaceutical future.
To support this shift, BENEO has expanded its knowledge-sharing activities. Alongside in-depth technical publications, our team hosts dedicated webinars where experts from academia and industry share practical experiences and discuss real-world challenges. Discover how formulation scientists are adapting binder strategies for twin-screw systems and what this means for future solid dosage development: register here to watch the recording of the latest webinar and hear expert insights and first-hand experiences with continuous processing.
Curious how granulation science is evolving in practice?
In a recent episode of Excipient Talk, Dr Michael Black, Senior Sales Manager Pharma at BENEO, speaks with Oliver Luhn about key insights from the 11th Granulation Conference in Hamburg. The discussion explores the future of twin-screw granulation, the growing role of moisture-activated dry binders, and why collaboration between universities and equipment manufacturers is accelerating innovation.
The episode offers practical perspectives from the field and highlights how excipient functionality is being re-evaluated in continuous systems.
Listen to the full episode of Excipient Talk and join the conversation:
Looking ahead
The move from batch to continuous manufacturing is more than a technical upgrade. It changes how formulations are designed. Excipients are no longer passive ingredients. They shape process efficiency, product quality and patient experience.
The key question for formulators is no longer simply “Which binder works?” but rather:
- How does this excipient perform in a continuous environment?
- Does it simplify the system?
- Does it support patient-centric design?
Answering these questions will define the next generation of solid dosage development.
Key takeaways
- Twin-screw granulation is accelerating the shift from batch to continuous pharmaceutical manufacturing.
- Continuous processes demand excipients with fast activation, consistent flow and high process stability.
- Short residence times in twin-screw granulation require excipients with predictable activation kinetics.
- Binder functionality plays a critical role in ensuring robust granule formation under short residence times.
- Patient-centric formulation requirements, such as taste and mouthfeel, must be considered alongside process performance.
- Multifunctional excipients can help simplify formulations and support efficient continuous production.
Frequently Asked Questions
What is twin-screw granulation in pharmaceutical manufacturing?
Twin-screw granulation is a continuous wet granulation process in which powders are mixed and granulated in an extruder equipped with two intermeshing screws. The process enables continuous production of pharmaceutical granules with precise control over mixing, moisture and residence time.
Why are excipients important in continuous manufacturing?
Excipients influence powder flow, granule formation and process stability. In twin-screw granulation, excipients must activate quickly and perform consistently under short residence times and tightly controlled process conditions.
References
ICH Q13 Continuous Manufacturing Guideline
ICH Q13 guideline on continuous manufacturing
FDA Continuous Manufacturing Overview
FDA perspective on continuous manufacturing