Masterarbeit

From Approval to Therapeutic Legitimacy: Lifecycle Governance of Prescription Digital Therapeutics in Mental Health

Dr Udita Bagchi (2026)

Zusammenfassung/Summary

Sprache/Language: English

Prescription digital therapeutics (PDTs) are emerging as a possible response to persistent gaps in mental-health care, including limited treatment capacity, long waiting times, fragmented care pathways and unequal access to support. However, their value cannot be assessed by technological promise alone. As software-based interventions that make disease-related therapeutic claims, PDTs require regulatory, evidentiary, reimbursement and data-governance frameworks that can recognise them as legitimate therapeutic interventions and maintain this legitimacy over time. 

This thesis examines how current regulatory and market-access systems shape the development, authorisation, adoption and lifecycle governance of mental-health PDTs. Its central argument is that these products should not be regulated as static software tools assessed only at market entry. Instead, they should be understood as adaptive therapeutic systems whose safety, performance and clinical value may change with software updates, behavioural design, patient engagement, data flows, implementation context, reimbursement conditions and, where relevant, AI-enabled personalisation. The analysis compares three regulatory environments. The United States represents an authorisation-oriented model in which PDTs may enter the market through existing medical-device pathways, while reimbursement and clinical integration often remain fragmented. The European Union provides a more formalised medical-device framework under the MDR, supported by software-specific guidance, post-market obligations and emerging AI-related requirements. Germany illustrates a reimbursement-linked model through the DiGA framework, where selected digital applications can become prescribable, reimbursable and visible within statutory healthcare. Across these systems, several regulatory challenges become apparent. Intended use functions as a central control point because it influences classification, evidence requirements, software-change flexibility, reimbursement prospects and real-world adoption. Evidence generation must also become more lifecycle-oriented, connecting clinical validation, study readiness, post-market surveillance, real-world evidence and software change control. This is particularly important for evidence version integrity, since the software version studied, the authorised therapeutic claim and the product actually used by patients must remain traceable over time. The analysis also identifies behavioural design, privacy, cybersecurity, interoperability, reimbursement, health technology assessment and equity as “hidden regulators” of therapeutic legitimacy, since they strongly influence trust, access, scalability and safe integration into care. In response, the thesis proposes a Lifecycle Therapeutic Legitimacy Framework for Mental-Health PDTs. This framework combines lifecycle accountability, therapeutic legitimacy and implementation-sensitive oversight. It is operationalised through five practical instruments: an Intended Use Architecture File, a PDT Study-Readiness Assessment, a Therapeutic Model Card, a Lifecycle Evidence Compact and a Privacy-by-Authoring Clinical Package.

The thesis concludes that mental-health PDTs may contribute meaningfully to future treatment approaches only if governance systems reflect their clinical, technical, ethical and system-level complexity. The key regulatory question is therefore not only whether these products can enter the market, but whether they can maintain therapeutic legitimacy across changing software versions, user behaviour, evidence expectations and healthcare contexts.

Seiten/Pages: 93

Annexes: 5, Seiten/Pages: 14