"There will only ever be one Alex Trebek, but I'm honored to be helping Jeopardy! out with this in January," said Jennings, one of the show's all-time top winners.
"I love spending time with bright people," said the longtime game show host. Trebek began hosting the trivia show in 1984 and continued for nearly four decades, even through bouts of chemotherapy.
"The doctors said they hadn't seen this kind of positive result in their memory," the Jeopardy! host told People magazine. "Some of the tumors have already shrunk by more than 50 percent."
The longtime game show host has described himself in the past as a political independent and has expressed interest in one day moderating a presidential debate as well.