The broader impact/commercial potential of this Small Business Technology Transfer (STTR) project is to develop a photocatalytic process to facilitate enhanced speed and efficiency for production of key intermediate chemicals for production of Remdesivir, a potential life-saving drug in the fight against COVID-19. Remdesivir has been identified as one of the most promising treatments for COVID-19; recently receiving fast-track approval for Phase III trials and compassionate use against this rapidly spreading and deadly disease. However, today Remdesivir is not an approved drug and is therefore not manufactured at scale. This project offers potential for accelerated production of Remdesivir by removing manufacturing bottlenecks of intermediates that threaten rapid scale-up and efficient manufacturing. Upon approval, process bottlenecks could inhibit mass-production, delay global availability and jeopardize millions of lives. An optimized production method for key intermediates is urgently needed to meet worldwide demand that will be critical in the race to control the pandemic. Potential problems with the current processes include costly and hazardous raw materials, low yields, expensive and specialized equipment required for harsh operating conditions and air- and water-free environments, and arduous purification and facility clean-up procedures. In addition, this project also provides a simplified, modular and faster approach for building libraries of derivative molecules to screen against COVID-19 and future viral threats.This STTR Phase I project proposes to develop an optimized manufacturing process for Remdesivir, one of the most promising COVID-19 therapeutic candidates identified to date, using photocatalysis, a powerful new chemical technology driven by light. Research objectives include using photocatalysis to develop a vastly superior synthesis route requiring fewer process steps, less toxic reagents and milder and safer reaction conditions. The new route will eliminate the need for specialized production equipment and procedures to maintain cryogenic temperatures and air- and water-free environments, will result in faster production times and overall higher yields, and will alleviate arduous purification and facility clean-up. The improved process will also facilitate installation of new molecular architectures and development of derivative molecules vital for efficacy screening against this and future viral threats. A second objective is to optimize the process for manufacturing at scale.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.