Samcro has been found to be suffering from a lung infection and plans for the rest of the season are on hold as a result.
Gordon Elliott's charge carried all before him in the novice ranks last season, winning the Ballymore Novices' Hurdle at the Cheltenham Festival in March.
He ran against his elders afterwards at Punchestown, but fell just as the race was beginning in earnest and a decision was taken in the autumn to remain over timber for a crack at the Champion Hurdle.
It has been far from a smooth ride this campaign, however, as the Gigginstown House Stud gelding was beaten by Bedrock on his return at Down Royal, before finding current champion Buveur D'Air a cut above in the Fighting Fifth Hurdle at Newcastle.
Sent off favourite for the Ryanair Hurdle at Leopardstown over Christmas, the seven-year-old beat only one home and connections stated afterwards that all plans were on hold as he would undergo a thorough check-up.
"He's got a lung infection and he could have had it for a while - it was very, very deep," Gigginstown's Eddie O'Leary told Press Association Sport.
"We'll do whatever is in the best interests of the horse now, he won't run again until he is well enough to run.
"He's been placed on antibiotics for 10 days, but it was quite a deep infection so we'll let him come back in his own time.
"It's unlikely that he'll run again this season, but not out of the question. Certainly Cheltenham is doubtful, but he could make Punchestown, we'll just have to see."