Global environmental and sustainability concerns are increasingly pressuring industries in all developing economies to align their supply chain operations with ecological, social, and economic responsibilities. This study investigates the extent to which Sustainable Supply Chain Management (SSCM) enablers are influencing firm-level productivity in a developing economy, and how effectively the practices of SSCM mediate this relationship. This research aims to determine the extent to which Sustainable Supply Chain Management (SSCM) enablers influence firm-level productivity in a developing economy, and how effectively SSCM practices mediates this relationship. Building on the Diffusion of Innovation (DOI) theory, the research adopts a well-structured design and employs Structural Equation Modeling (SEM) to test the designed conceptual framework. The findings show that, while direct effects of enablers on productivity are limited, SSCM practices play a critical mediating role in translating these enablers into measurable performance-based improvements. The study contributes theoretical insights by extending DOI theory into the pharmaceutical supply chain context and offers practical guidance for managers and policymakers in developing economies by seeking to enhance competitiveness through sustainable practices.