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Continuous manufacturing has been promoted as a transformative alternative to batch pharmaceutical production because it can reduce equipment footprint, shorten development-to-commercialisation timelines, and enable more responsive quality assurance. Its appeal rests on the idea that material flows through an integrated process rather than waiting in isolated unit operations. Yet the technical maturity required to make that flow reliable is often understated. The central problem is that continuous operation is sometimes treated as intrinsically superior to batch production, as though continuity alone guarantees better quality. In practice, quality depends on the ability of sensors, models, actuators, supervisory logic, and operators to detect and correct deviations fast enough to prevent poor material from propagating through the line. Without that control capability, continuous systems may amplify rather than resolve process vulnerability. This critical review examines continuous pharmaceutical manufacturing through three linked lenses: control architecture design, process robustness, and regulatory translation. It asks whether current systems are sufficiently controlled to justify claims of superior quality, whether robustness is assessed with appropriate metrics, and whether regulatory frameworks have matured enough to support dynamic manufacturing strategies. The review deliberately treats continuous manufacturing as a socio-technical system rather than as a purely technological upgrade. The evidence indicates that continuous manufacturing has advanced substantially, particularly in direct compression, wet granulation, process analytical technology, residence-time modelling, soft sensing, and model predictive control. However, many demonstrations remain limited by narrow disturbance scenarios, incomplete treatment of start-up and shutdown, uncertain model maintenance requirements, and uneven translation into routine good manufacturing practice. Regulatory acceptance is progressing, but unresolved questions remain around batch definition, traceability, adaptive control validation, and lifecycle change management. The review concludes that continuous manufacturing is not an automatic guarantor of pharmaceutical quality. Its value depends on control-centric process design, standardised robustness assessment, credible digital and analytical infrastructure, and regulatory alignment that recognises dynamic process operation. The future pathway requires stronger pre-competitive collaboration, more realistic stress testing, and regulatory science that keeps pace with advanced control strategies.

Pharmaceutical technology evaluation has traditionally been organized around pharmacokinetic performance, with bioavailability occupying a privileged position as a marker of formulation success. This emphasis has been scientifically productive because it links dosage form design to systemic exposure and supports comparability across products. Yet bioavailability captures only one part of the pathway between a pharmaceutical technology and sustained therapeutic benefit. A product may deliver favorable exposure under controlled conditions while still failing when introduced into everyday patient use. The central problem is that bioavailability-centered evaluation often assumes idealized conditions of administration, storage, handling, and persistence. In practice, patients must swallow, inject, inhale, store, prepare, remember, tolerate, and continue medicines within complex personal and healthcare environments. Technologies that improve exposure may therefore generate limited value if they are difficult to use, fragile under real-world variability, or unable to support continuity of treatment over time. This creates a gap between technical success and therapeutic success. The objective of this article is to propose a systems-based evaluation model for pharmaceutical technologies. The model treats usability, robustness, and therapeutic continuity as co-equal dimensions that complement traditional pharmacokinetic endpoints. Usability captures the human–technology interface, robustness captures performance consistency under realistic variability, and therapeutic continuity captures sustained benefit across time and care settings. Together, these dimensions broaden the meaning of pharmaceutical performance. The proposed model defines each dimension, explains their interactions, and translates them into a practical evaluation framework. It argues that usability, robustness, and therapeutic continuity should not be treated as late-stage refinements after bioavailability has been optimized. Instead, they should be incorporated early in product design and carried through development, assessment, and post-translation evaluation. Two tables are used to contrast the dominant bioavailability-centered paradigm with a systems-based view and to present the operational structure of the proposed model. Adopting a systems-based evaluation paradigm can help pharmaceutical technologies become not only pharmacokinetically effective but also usable, resilient, and capable of sustaining therapeutic benefit in practice. Such a shift does not diminish the importance of bioavailability. It places bioavailability within a broader causal architecture of real-world performance. The result is a more complete foundation for pharmaceutical technology assessment and patient-centered product development.

Pharmaceutical quality is often operationalized through stability testing, in which products are exposed to defined temperature and humidity conditions to support shelf-life assignment. This practice is indispensable, but it can create a narrow interpretation of quality when stability under controlled chamber conditions is treated as evidence of real-world performance. Products do not move through idealized chambers; they move through development uncertainty, manufacturing variability, distribution stress, and patient-level handling. This article argues that the dominant stability paradigm has encouraged a conceptual conflation between stability and robustness. Stability testing primarily asks whether a product remains within specification under predefined storage conditions for a defined period. Robustness, by contrast, asks whether the product–process–use system can continue to deliver acceptable quality when exposed to interacting stresses across the full lifecycle. The objective of this article is to develop an Integrated Robustness Theory for pharmaceutical products. The theory frames robustness as a system-level property spanning development, manufacturing, storage, and administration. It proposes that quality should be understood not only as shelf-life survival but also as resilient performance under realistic and combined stress conditions. The article critiques the limits of stability testing, defines robustness dimensions across lifecycle phases, and develops a systems-based framework for translating robustness into development strategy, manufacturing control, storage evaluation, and administration design. Three tables are used to map lifecycle robustness dimensions, storage stress gaps, and the integrated theory. The central conclusion is that pharmaceutical quality assurance must move beyond shelf-life thinking toward lifecycle robustness thinking.