Toronto councillor and former mayor Rob Ford's cancer has not responded to his latest chemotherapy treatment, but his doctors hope his condition will improve enough to try another drug cocktail, says his chief of staff.

According to Dan Jacobs, Ford is not healthy enough to try the next group of drugs that his doctors would like to administer, but they are waiting for him to recover.

In all, Ford has undergone nine rounds of chemo since his diagnosis, Jacobs said.

Meanwhile, Ford, councillor for Ward 2, remains at Mount Sinai Hospital "with his family beside him," according to a statement issued by his office on Thursday night.

Jacobs said that at least one family member is with Ford at all times. Some family members spent the night with him in hospital last night, and may stay there again tonight, he said.

The family statement issued Thursday followed social media rumours that suggested Ford had died.

Earlier this month, Doug Ford said his brother is pursuing targeted chemotherapy under the Panov program at Mount Sinai.

That treatment involves implanting pieces of tissue from a patient's tumour into mice, letting those tumours grow for three months and then testing different chemotherapy treatments to see if one will be successful.

That treatment is continuing, according to Jacobs.

Ford, 46, was diagnosed with an aggressive form of cancer called liposarcoma, which grows in fat cells, after a tumour was discovered in his abdomen in the fall of 2014. The diagnosis forced him to withdraw from that year's mayoral race.

Last spring, after receiving some treatment, Ford had aggressive surgery to remove the tumour. However, last October, he was hospitalized again before it was revealed that he had a growth on his bladder.

His brother Doug said in November that Ford had two tumours on his bladder.