According to The Sun, the former lobbyist and political adviser mouthed the word “pain” as nurses moved his body whilst Kate was watching on video call.
The Good Morning Britain presenter said Derek's tracheotomy tube has also been removed and he is now able to breathe without a ventilator.
"It’s a case of trying to balance belief, hope, optimism with reality," Garraway said.
"But we have had a breakthrough, which was both amazing yet heartbreaking.
"It happened when the nurses were moving Derek, as part of his treatment, to trigger the sensation of gravity because he’s been horizontal for so long."
She said that while it was “heart wrenching” that "pain" was her husband’s first word, the fact he communicated at all was a "huge breakthrough".
Derek, 53, from Chorley, was first admitted to hospital in March and was placed in a medically induced coma in April after his condition seriously deteriorated.
After seven months of intensive treatment, it is believed that Derek's ongoing battle with COVID-19 and its after effects is one of the longest on record.
Kate has previously said that Derek's recovery will be a slow process as the virus has "attacked everything", and doctors have warned her that he might never fully recover.
Garraway, also 53, has shared regular updates on her husband’s health through social media and on ITV’s Good Morning Britain.
She is also reportedly working on a new documentary, expected to air on ITV early next year, where she will speak to a range of people about how COVID-19 has affected their lives.
The couple married in 2005 and have two children - Darcey, 14, and 10-year-old Billy - who have been unable to visit their father due to the infection risk.
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