A former Chinese e-commerce executive in the final stages of a rare disease is still working 12-hour days, devoting what time he has left to accelerating the search for a cure. Cai Lei, 48, a former vice-president of JD.com, one of China’s largest e-commerce companies, has spent seven years battling amyotrophic lateral sclerosis (ALS), an incurable disease that progressively attacks motor neurons. His condition has recently deteriorated to an advanced stage.