Pavlik was due to face fellow American Williams in Atlantic City on December 5 but a hand problem led to the Ohio boxer being advised not to put his WBC and WBO titles on the line in six weeks.
"This morning we were advised that Kelly Pavlik's recovery of his left hand has not progressed as projected by Dr Peter J. Evans, director of the Cleveland Clinic Upper Extremity Centre," Top Rank president Todd duBoef said in a statement.
"As a result of this Kelly is unable to close his left hand which prohibits him from being prepared for a December 5 middleweight championship defence against Paul Williams.
"We at Top Rank are disappointed by this unexpected development in his recovery.
"Once Pavlik is cleared medically by Dr Evans we will pursue all avenues with regards to a future bout."
Pavlik, 27, last fought in February when he defended his titles in his native Youngstown, Ohio, stopping Marco Antonio Rubio in nine rounds.