INTRODUCTION:
Despite the central role of public policy in shaping innovation uptake and population health, health innovation policy implementation remains under studied. Digital therapeutics (DTx) are government-regulated evidence-based digital interventions designed to address healthcare challenges of quality, accessibility, and cost. Scaling DTx extends beyond the conventional translational research pathway and requires a health innovation system, integrating health service and innovation activities, financing, resources, and governance. This study examine how Hainan Provincial Government’s DTx policy package was implemented, and how it contributed to integrating local health and innovation systems to support DTx development, implementation, and population health improvement.

METHODS:
We used a multi-method observational study design, which combined policy mapping and semi-structured interviews, guided by Crable et al.’s (2022) recommendations on policy-optimized EPIS framework. 33 operational “lille P” policy documents linked to the Hainan DTx “big P” policy, from October 2022 to October 2025 were identified and analyzed using directed content analysis. Transcripts from 36 purposively sampled interviewees were analyzed thematically following Braun and Clarke’s (2021) approach.

RESULTS:
Implementation of the DTx policy unfolded across multi-levels contexts involving regulators, payers, street-level bureaucrats, technology developers, healthcare professionals, and end users. The DTx policy contributed structured outputs in regulatory pathway, real-world application, and business environment domains. System outcomes are proximal outcomes between policy implementation outcomes and policy goals. Key determinants of implementation success included inter-departmental coordination and service environment (outer context); incentive alignment (inner context); interoperability of the DTx-embedded information systems and public–academic-industry partnerships (bridging factors); and policy–context fit (innovation factors).

CONCLUSIONS:
The Hainan case illustrates how a coordinated policy can accelerate DTx large-scale implementation with equitable access and sustainability, and offers jurisdictions a potential transferable structure for designing health innovation policies. Our study advances policy-focused implementation science in digital health and generates a policy implementation logic model through a system change perspective.