Jennings conducted interviews for "America's Health Insurance Crisis," narrated by Charlie Gibson and scheduled to air Dec. 15, the New York Post reported.
Jennings was supposed to narrate the program but the effects of chemotherapy left his voice too weak, the newspaper said.
An ABC News spokesman said Jennings had planned the special to be the first of a series confronting problems in the U.S. healthcare system.
Jennings died Aug. 7 at age 67.
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