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. Unable to move or speak, Cai can now communicate and work only by using eye-tracking technology to type on a computer.

His assistant told the mainland media outlet Yitiao that Cai has survived several near-death episodes, including one in which phlegm blocked his throat, leaving him unable to breathe for about a minute.

Even the smallest movements now require extraordinary support. Four carers are needed to help him rise from a chair or return to bed, while muscle atrophy causes him pain and numbness after sitting for long periods.