	US 12,187,813 B2
	Methods of identifying opioid cyclic peptides
Predrag Cudic, Boca Raton, FL (US); and Jay McLaughlin, Gainesville, FL (US)
Assigned to Florida Atlantic University Board of Trustees, Boca Raton, FL (US); and University of Florida Research Foundation, Gainesville, FL (US)
Filed by Florida Atlantic University Board of Trustees, Boca Raton, FL (US); and University of Florida Research Foundation, Gainesville, FL (US)
Filed on Feb. 10, 2023, as Appl. No. 18/167,350.
Application 18/167,350 is a division of application No. 16/257,580, filed on Jan. 25, 2019, granted, now 11,578,100.
Claims priority of provisional application 62/649,290, filed on Mar. 28, 2018.
Prior Publication US 2023/0257418 A1, Aug. 17, 2023
Int. Cl. A61K 31/4045 (2006.01); A61K 9/00 (2006.01); A61K 47/64 (2017.01); A61K 47/65 (2017.01); A61P 25/04 (2006.01); A61P 25/06 (2006.01); A61P 25/16 (2006.01); A61P 25/18 (2006.01); A61P 25/28 (2006.01); A61P 25/36 (2006.01); C07K 5/12 (2006.01); C07K 7/64 (2006.01); A61K 38/00 (2006.01); C40B 40/10 (2006.01)

CPC C07K 5/12 (2013.01) [A61K 9/0043 (2013.01); A61K 31/4045 (2013.01); A61K 47/64 (2017.08); A61K 47/65 (2017.08); A61P 25/04 (2018.01); A61P 25/06 (2018.01); A61P 25/16 (2018.01); A61P 25/18 (2018.01); A61P 25/28 (2018.01); A61P 25/36 (2018.01); C07K 7/64 (2013.01); A61K 38/00 (2013.01); C40B 40/10 (2013.01)]

14 Claims

1. A method of identifying opioid cyclic peptides comprising:

i) providing a combinatorial library comprising a plurality of distinct cyclic peptides of the general Formula II:

	(SEQ ID NO: 18)
	Tyr-Ala-Ser-Pro-Lys-cyclo-[Cys-Phe-Arg-XXXXX-

	Leu-Ala-Cys]-Thr,

wherein each X is an amino acid selected from the group consisting of: D-amino acid, L-amino acid, non-natural synthetic amino acid, naturally occurring amino acid, and a mixture thereof;

ii) screening the plurality of cyclic peptides for binding affinity to μ-opioid receptor (MOR), δ-opioid receptor (DOR), and κ-opioid receptor (KOR) in mammalian cells

using a screening assay to identify any cyclic peptide that has binding affinity for at least one opioid receptor a candidate opioid cyclic peptide; and

iii) testing any candidate opioid cyclic peptide using an in vitro or in vivo functional activity assay for agonist effects on the at least one opioid receptor, wherein

any candidate opioid cyclic peptide that has an affinity for at least one opioid receptor and that has agonist effects on the at least one opioid receptor is an opioid cyclic peptide.