The COVID-19 pandemic has influenced the world in a way that none of us could have imagined. Since February 2020 unplanned changes to daily routines due to the mandatory isolation and social distancing requirements have occurred across the globe. It is the greatest global healthcare crisis of our generation. The COVID-19 pandemic presents enormous challenges in particular to medical research, as these disruptions have wreaked havoc on clinical trials in progress as well as those in the planning stages. For example, the COVID-19 pandemic is reducing the ability and willingness of trial subjects and staff to access clinical sites, disrupting timely data collection or necessitating a move to virtual data collection. These challenges may result in difficulties in complying with protocol-specific procedures, including administration or use of the investigational product or compliance with protocol-required visits, efficacy assessments, and laboratory/diagnostic tests. In many situations, these challenges cause delays or halting of clinical trials altogether.In recognition of these unprecedented challenges, we decided to dedicate a Special Issue of Statistics in Biopharmaceutical Research to the statistical challenges in the conduct and management of ongoing clinical trials during the COVID-19 pandemic. This special issue highlights and discusses critically important topics, including the impact on trial integrity and interpretability, issues around trial management and operations, estimands and missing data handling as well as the application of novel trial designs and analysis approaches. This Special Issue consists of peer-reviewed articles and commentaries, reflecting the vibrancy of ideas and discussions around the COVID-19 pandemic.Meyer et al. ( 2020) put forward a number of strategies and recommendations to assess and address issues related to estimands, missing data, validity and modifications of statistical analysis methods, need for additional analyses, ability to meet objectives as well as overall trial interpretability. This article has been translated into Japanese by the Data Science Expert Committee of the Japan Pharmaceutical Manufacturers Association (JPMA) and available on their website (JPMA 2020). Collins and Levenson (2020) as well as Hemmings (2020) provide insightful regulatory commentaries on the article by Meyer et al. (2020). Akacha et al. (2020) discuss implications of the COVID-19