Clinical trials can be big, cumbersome and unpredictable. Patients can be hard to recruit, and then their care has to be carefully coordinated through complex health-care systems, all while an ever-growing amount of data is collected and analysed. But if you could build a clinical trial operating system from the ground up, could you tame these beasts? Cardiologist Jessica Mega was running 10,000-plus patient trials at Harvard before jumping at the opportunity to take this task on at Google X in 2015. As chief medical and scientific officer at Verily, Alphabet’s resulting life sciences subsidiary, she now oversees a stable of projects that include immune profilers, wearable sensors and bioelectronic medicines. In May, Verily partnered with four large pharmaceutical firms to put its evolving clinical trial operating system to the test. She spoke with Asher Mullard about how her team is working to bring clinical trials to heel by optimizing patient recruitment and re-imagining health-care data.