The Future Of Continuous Is Integrated Manufacturing: The 4 Misconceptions About A Lean Process

By Richard Steiner, Pharmatech Associates

For more than three decades, pharmaceutical continuous manufacturing (PCM) has been positioned as the future of drug production, offering greater efficiency, agility, and reliability than traditional approaches.

Despite compelling proof points and regulatory support, adoption remains surprisingly limited. That gap is driven by a set of pervasive myths and outdated assumptions that continue to shape how organizations evaluate, implement, and ultimately delay PCM.

To unlock its full potential, the industry must move beyond legacy perceptions and reframe PCM for what it is: an integrated system that, when paired with predictive insight and end-to-end process understanding, can transform quality, efficiency, and long-term performance.

The Origin Of PCM And Lingering Hesitations

In the 1990s, Knoll’s hot-melt extrusion (Meltrex) system demonstrated what was possible: integrating multiple unit operations into a seamless, controlled process capable of producing highly consistent oral solid dosage (OSD) products.

That system solved challenges that had long plagued batch manufacturing — particularly around consistency and material variability. With gravimetric loss-in-weight (LiW) feeding and twin-screw extrusion, it enabled precise control over formulation at a molecular level, eliminating variability introduced by traditional blending and intermediate handling steps.

Many called it the “silver bullet solution” for the future of OSD pharmaceutical manufacturing. And yet, 30 years later, practitioners in the pharmaceutical industry are still debating if PCM is viable, applicable, and worth the investment. Continuous manufacturing still represents a fraction of overall pharmaceutical production — particularly in OSD, where it accounts for well under 1% of global volume (based on the WHO’s Defined Daily Dose).

So why hasn’t pharmaceutical adoption kept pace with innovation? The answer lies in how the industry defines — and misunderstands — continuous manufacturing.

Common Misconceptions About PCM

Myth #1: Continuous Manufacturing Means Everything Must Run Continuously

This is perhaps the most common — and most limiting — misconception about PCM.

In reality, very few pharmaceutical manufacturing systems are fully continuous from end to end. Most successful implementations are hybrid or semi-continuous, combining continuous core processes with discrete or batch-based steps where appropriate.

Take continuous direct compression (CDC), one of the most widely adopted forms of PCM today. In CDC, raw materials are continuously fed, blended, and compressed into tablets in a single integrated flow. However, downstream processes such as coating may still operate in a semi-continuous or mini-batch mode.

Continuous manufacturing is not defined by whether every unit operation runs simultaneously. It is defined by continuity of control, quality, and data.

What matters is the ability to:

• monitor processes in real time
• maintain consistent product quality
• respond dynamically to variability
• minimize waste through targeted material diversion.

In fact, one of PCM’s greatest advantages is its ability to isolate and remove small quantities of out-of-spec material, rather than discarding entire batches.

This is where concepts like residence time distribution (RTD) become critical. Once viewed as a risk, RTD is now a well-understood and modeled parameter that enables precise tracking of material through the process. It allows manufacturers to define exactly where variability occurs and act on it immediately.

The takeaway is simple: PCM is not about forcing every step into continuous mode. It’s about designing a system where continuity delivers better control, quality, and productivity.

Myth #2: Continuous Manufacturing Only Makes Sense at Blockbuster Scale

Another persistent belief is that PCM only delivers value at high volumes, making it impractical for smaller products, niche therapies, or early-stage development.

While it’s true that large-scale production can maximize efficiency, this view overlooks one of PCM’s most powerful advantages: agility.

Continuous systems are inherently flexible. They allow manufacturers to scale by adjusting run time rather than redesigning processes or transferring between equipment. That means:

• no traditional scale-up risk
• faster progression from development to commercialization
• greater consistency across clinical and commercial batches.

For innovators, this translates directly into accelerated time to market — often by several months. And in a competitive landscape, those months matter. Earlier entry can drive higher peak sales, increased market share, and significantly improved net present value across the product life cycle.

For contract manufacturers, PCM enables more efficient tech transfer and scalable clinical supply. For generics and OTC manufacturers, it offers a pathway to improved productivity and cost competitiveness.

In other words, the business case for PCM is not one-size-fits-all, but it is far broader than many assume.

The real question is not whether your product is large enough for continuous manufacturing. It’s whether your organization is prepared to leverage its flexibility.

Myth #3: Regulators Aren’t Ready for Continuous Manufacturing

This concern that regulators aren’t prepared for PCM, while understandable, is increasingly outdated.

Global regulatory bodies — including the FDA, EMA, and PMDA — have not only accepted continuous manufacturing but actively encouraged its adoption. Frameworks such as ICH Q13 provide clear guidance on how to design, implement, and validate continuous processes.

More importantly, regulators are not focused on whether a process is batch or continuous. Their priority is consistent product quality.

So, what do regulators care about when it comes to PCM?

• Control strategies
• Process monitoring and data integrity
• Material traceability
• Sampling and testing approaches
• Validation and life cycle management

Continuous manufacturing, when implemented correctly, often strengthens these areas. Real-time process analytical technologies (PAT), integrated data systems, and advanced control strategies enable a level of visibility and responsiveness that batch processes struggle to match.

The shift, then, is not about convincing regulators. It’s about aligning internal teams to meet a different standard of control.

Myth #4: Continuous Manufacturing Is Primarily About Equipment

This is perhaps the most dangerous misconception, because it leads organizations to invest in technology without fully understanding what drives success.

Equipment matters. But it is not the defining factor. The true foundation of PCM is control strategy and system integration.

A successful continuous process requires:

• deep understanding of material attributes
• robust in-process monitoring
• defined sampling strategies and acceptance criteria
• integration across unit operations
• real-time data analysis and decision-making.

In practice, this evolves across three levels:

• Level 1: Foundational knowledge — Understanding process parameters, managing variability, and applying traditional QA/QC approaches.
• Level 2: Technology enablement — Implementing PAT, adopting quality by design (QbD), and building data infrastructure.
• Level 3: Full integration — Leveraging predictive models, advanced process control, and digital systems to anticipate and respond to changes.

Not all processes need this Level 3 control. However, it is at this third level where continuous manufacturing delivers its full value — and where many implementations fall short.

The Hidden Risk: Platform Decisions Made Too Early

One of the most overlooked challenges in PCM adoption is timing. Too often, manufacturing platforms are selected based on early feasibility success, before the full life cycle implications are understood. What appears scientifically sound in early development can become operationally limiting in commercial production.

These decisions are difficult to reverse. They shape:

• cost of goods over 10 to 15 years
• scalability and tech transfer complexity
• facility design and utilization
• long-term product competitiveness

Getting it wrong can lead to higher costs, delayed launches, and lost market opportunity. This is where the industry must evolve from empirical decision-making to predictive strategy.

From Empirical To Predictive: A New Approach To PCM

The tools to make better decisions already exist. Today’s leading organizations are integrating:

• physicochemical modeling to predict stability
• process modeling to assess manufacturability
• economic modeling to evaluate life cycle cost
• digital twins to simulate plant performance and scalability.

These capabilities allow manufacturers to evaluate trade-offs before committing to a platform, thus reducing risk and optimizing outcomes across the entire product life cycle.

A Shift In Perspective: From Continuous To Integrated

Perhaps part of the challenge lies in terminology itself. “Continuous manufacturing” suggests an all-or-nothing approach, an expectation that everything must flow at all times. But as we’ve seen, that’s not how successful systems operate.

A more accurate framing may be integrated manufacturing. This emphasizes:

• coordination across processes
• continuity of data and control
• flexibility in execution
• alignment with lean manufacturing principles.

In this context, continuous processes become a tool, not a constraint.

The Path Forward

Advancements in manufacturing technology have unlocked the potential for meaningful leaps in quality, efficiency, and control — enabling real-time monitoring, reduced waste, greater agility, and stronger alignment with lean manufacturing principles.

But technology alone does not deliver that value.

To fully realize the promise of PCM, organizations must move beyond empirical decision-making and embrace predictive analysis, robust control strategies, and end-to-end life cycle thinking. Platform choices made early will define years of manufacturing performance, cost structure, and market success. Without the right foundation, those decisions can limit, rather than enable, long-term value.

The takeaway is clear: PCM is an enabler of better manufacturing, but only when implemented with intention. When predictive insight, system integration, and operational expertise come together, PCM becomes a strategic advantage that drives performance across the entire product life cycle.

About The Author:

Richard Steiner is senior manager, business strategy, at Pharmatech Associates. He has extensive experience in the high-end equipment industry, working in global business networks. He has engineering expertise in continuous processing/manufacturing of oral solid dose pharmaceuticals, hot melt extrusion of pharmaceuticals, and twin- and single-screw extrusion of thermoplastic materials.