The structure of R&D expenditure by phase of development continues to change annually, reflecting the different stages of the pipeline across companies. Overall, just under 30% of all R&D expenditure is dedicated to Phase III clinical trials. Averaged over this period, net increases in shares were recorded for pre-clinical, phase I and submission periods. A substantial decline (12%) in roll-outs and line extensions was also recorded. Longer time trends are needed to conclude any significant changes in the structure of R&D expenditure. Given the changes to clinical research design, there may be some crossover in the expenditure between the clinical research phases which may blur the differentiation between the different phase categories.