Fig. 2

a Time needed for project discontinuation; 1990–1999 (blue), 2000–2009 (red). We highlight in green the area between the two curves. We show the fraction of projects that are discontinued after x years from the start of preclinical research. The distribution accounts for a maximum discontinuation time of 8 years, so we focus on projects started before 2010. Inset: boxplot of the time interval between patent filing and market launch years, based on the year of market launch, in three different time intervals (1990–1999, 2000–2009, 2010–2017). b Median phase duration per each phase of the drug development process, in three different time intervals (phases started in 1990–1999, 2000–2009, 2010–2013). The duration of a development phase in a year is defined as the median time required to the projects that started the focal phase in the given year to pass to the subsequent phase. The median duration is computed considering only transitions with duration lower than or equal to 4 years, to make a sound comparison across decades. When the median of a phase duration is not significantly different from that of the previous decade, the corresponding value is barred