After Dobie Brown pleaded guilty to aiding and abetting the possession with intent to distribute of 50 grams or more of a mixture or substance containing cocaine base, in violation of 21 U.S.C. § 841(a)(1) and 18 U.S.C. § 2, the district court 1 sentenced him to 151 months in prison and 5 years of supervised release. On appeal, Brown’s counsel has moved to withdraw, filing a brief under Anders v. California, 386 U.S. 738, 87 S.Ct. 1396, 18 L.Ed.2d 493 (1967), and Brown has filed a pro se supplemental brief. Having carefully reviewed the record and the submissions on appeal, we affirm.

We address seriatim the arguments raised in the Anders and pro se briefs: (1) any issue as to Brown’s competency to plead guilty is not properly raised for the first time in this direct criminal appeal, see United States v. Murphy, 899 F.2d 714, 716 (8th Cir. 1990); (2) Brown was represented by counsel throughout these proceedings, and any issue regarding ineffective assistance is not properly before us, see United States v. Ramirez-Hernandez, 449 F.3d 824, 826-27 (8th Cir. 2006); (3) Brown exercised his right of allocution; and (4) his sentence, which falls within the advisory Guidelines range, is not unreasonable, see United States v. Feemster, 572 F.3d 455, 461 (8th Cir. 2009) (en banc).

Having reviewed the record under Penson v. Ohio, 488 U.S. 75, 109 S.Ct. 346, 102 L.Ed.2d 300 (1988), we find no nonfrivo-lous issues for review. Accordingly, the judgment is affirmed, and we grant counsel’s motion to withdraw.