Effect of alternative dosing strategies of pembrolizumab and nivolumab on health-care emissions in the Netherlands: a carbon footprint analysis

Background: 

Hospitals contribute substantially to greenhouse gas emissions and face a moral obligation to prioritise emission reduction. Drugs constitute an important component of the greenhouse gas emissions of hospitals. Alternative dosing strategies (ADS) have been implemented to improve the cost-effectiveness of pembrolizumab and nivolumab. However, the impact of these ADS on greenhouse gas emissions remains unknown. Therefore, we aimed to analyse the effect of ADS implementation on the carbon emissions of treatment with pembrolizumab and nivolumab. 

Methods: 

We used a process-based lifecycle assessment to quantify the environmental impact of pembrolizumab and nivolumab, focused on equivalent carbon dioxide emissions (CO₂e). Lifecycle inventory and impact data from Erasmus University Medical Center (Rotterdam, Netherlands) were used to calculate the CO₂e for pembrolizumab and nivolumab, their dosing intervals, and the impact of ADS on CO₂e. The functional unit of the study was the administration of a single dose of pembrolizumab or nivolumab. Findings: In 2022, the annual carbon emissions related to pembrolizumab and nivolumab treatment in the Erasmus University Medical Center were 445 tons of CO₂e, averaging 94 kg of CO₂e per dose. Pharmaceutical production was the main driver of treatment-related carbon emissions (mean 92·9% of total emissions). Applying ADS resulted in 21–26% and 9–11% CO₂e reductions for pembrolizumab and nivolumab, respectively. 

Interpretation: 

This study shows the environmental impact of pembrolizumab and nivolumab treatment and calls for further implementation of ADS for pembrolizumab, nivolumab, and other anti-PD-(L)1 monoclonal antibodies, and more sustainable pharmaceutical production processes. Our findings create environmental awareness and contribute to the promotion and understanding of health-care practices with lower carbon emissions.