OBJECTIVES: Social Return on Investment (SROI) methodology captures broader impact of medicines, including social, environmental and economic outcomes. Patients with Parkinson's disease (PD) become increasingly dependent on family and carers as their disease progresses. Traditional cost-effectiveness analyses (CEA) only consider patient and payer-related outcomes, failing to acknowledge impacts on families, carers, and broader society. This novel Social Return on Investment (SROI) analysis evaluates the broader impact created by improving access to levodopa-based device-aided therapies (DATs) for people living with advanced PD (aPD) in Australia.

METHODS: A forecast SROI analysis over a three-year time horizon was conducted. People living with aPD and their families were recruited for qualitative interviews or a quantitative survey. Secondary research and clinical trial data were used to supplement primary research. Financial proxies were assigned to each final outcome based on willingness-to-pay, economic valuation, and replacement value. Cost inputs were sourced from Pharmaceutical Benefits Schedule and Medicare Benefits Scheme prices.

RESULTS: Twenty-four interviews were conducted and 55 survey responses were received. For every $1 invested in access to levodopa-based DATs in Australia, an estimated $1.79 of social value is created. Over 3 years, it's estimated AU$277.16 million will be invested and AU$406.77million of social return will be created. This value is shared between people living with aPD (28%), their partners (22%), children (35%), and the Australian Government (15%). The majority of value created is social and emotional, including reduced worry, increased connection to friends and family, and increased hope for the future.

CONCLUSIONS: This SROI, complementing traditional CEAs, has captured the substantial impact and positive social return that can be created by investing in levodopa-based DATs. Over 50% of the value is created for the partners and children of people living with aPD quantifying the value that access to levodopa-based PD treatment can create from a social, environmental and economic perspective.