...the old model of drug discovery is no longer working well.
This so-called blockbuster method - which commits large sums of money to finding a drug that promises to treat a huge proportion of the population, and generate swathes of cash to cover other experimental losses - can no longer sustain the industry.
The model is inefficient. Nine times out of 10, molecules which show promise at the early stage are destined for failure at later trials.
Pharmaceutical companies are also under pressure as patents for some of their most lucrative drugs expire.
Manufacturers face an uphill struggle with science too. Some argue that in its most successful years, the big pharmaceutical firms picked off the "low-hanging fruit" - the compounds that were easiest to discover and turn into drugs.