Dr. Larry Cripe told reporters Pagano has fared well in tests administered to monitor his case of acute promyelocytic leukemia.
The doctor said the first-year coach's white blood cell count is now normal, adding there was no sign the cancer had spread to his bone marrow.
But Cripe cautioned the diagnosis wasn't the same as being cured.
"We need to keep going and we will not be able to use the word 'cure' for four or five years," Cripe told the Indianapolis Star.
The news came after Pagano, 52, had visited the Colts following their 23-20 victory over the Miami Dolphins Sunday, during which he gave an emotional postgame speech.
The Colts have gone 4-1 since Pagano took an indefinite leave of absence in late September following his leukemia diagnosis.