What is the test for reversal of a prosecutor's summation when a defendant raises objections to the content of the summation?

prejudice to the defendant, thereby depriving him of his right to a fair trial." United States v. LaMorte, 950 F.2d 80, 83 (2d Cir. 1991). A defendant asserting that a prosecutor's remarks warrant reversal "face[s] a heavy burden, because the misconduct alleged must be so severe and significant as to result in the denial of [his] right to a fair trial." United States v. Locascio, 6 F.3d 924, 945 (2d Cir. 1993). Where, as here, a defendant raises objections to the content of a prosecutor's summation for the first time on appeal, we review for plain error, "requiring us to reject any assignment of error that does not amount to flagrant abuse . . . ." United States v. Williams, 690 F.3d 70, 75 (2d Cir. 2012).