In this May 5, 2019, file photo Alex Trebek poses in the press room at the 46th annual Daytime Emmy Awards at the Pasadena Civic Center in Pasadena, Calif. Trebek said Tuesday, Sept. 17, that he’s had a setback in his battle with pancreatic cancer and is undergoing chemotherapy again. Credit: Richard Shotwell | AP

Alex Trebek, beloved host of “Jeopardy!,” announced Tuesday morning that he had resumed chemotherapy for his stage-4 pancreatic cancer, weeks after telling fans that he finished treatment.

“I was doing so well,” Trebek told “Good Morning America” on Tuesday. “And my numbers went down to the equivalent of a normal human being who does not have pancreatic cancer.”

“So we were all very optimistic. And they said, ‘Good, we’re gonna stop chemo, we’ll start you on immunotherapy,’” he recalled.

The optimism was short-lived. “I lost about 12 pounds in a week and my numbers went sky high, much higher than they were when I was diagnosed,” he said. “So the doctors have decided that I have to undergo chemo again, and that’s what I’m doing.”

America’s most famous game show host has provided anxious fans with frequent updates about his condition. Trebek first revealed his diagnosis in March, promising viewers that “I’m going to fight this.”

By May, his cancer was “near remission” and he was responding well to chemotherapy, he told People Magazine.

Finally, in August, America seemed to breathe a sigh of relief when the “Jeopardy!” host announced in a video that his chemotherapy treatments had ended and he would appear for another season of his iconic show.

But now, Trebek said his journey to recovery had become more challenging.

“In terms of getting my strength back, that hasn’t happened, unfortunately,” Trebek told “GMA” on Tuesday. “My hair started to go back but now I have to undergo chemo again.”

He shared that “for moments, that for no reason at all, I feel this surge of sadness, depression,” but that he continuously told himself to “just keep going.”

Throughout his cancer battle, Trebek has maintained an optimistic public tone about his disease, which has a very slim survival rate. But he has also been honest, and admitted Tuesday that “I realize that there is an end in sight for me just as there is for everyone else.”

He’d assured his “Jeopardy!” staff that “when I do pass on, one thing they will not say at my funeral is, ‘He was taken from us too soon.’”

“I’m 79 years old, I’ve had one hell of a good life, and I’ve enjoyed it,” Trebek said. “The thought of passing on doesn’t frighten me, it doesn’t.”