This refers to one of the inscriptions seen on the mandala.
"This sutra provides good medicine for the ills of the people of Jambudvipa. If a person who has an illness is able to hear this sutra, then his illness will be wiped out and he will know neither old age or death." from the Yakuo [Medicine King] Chapter of the LS. {Watson translation}
It appears that Nichiren did not designate a recipient for this one.