Abstract: A method for treating opioid use disorder comprises administering to a subject a pharmaceutical composition comprising a cyclic peptide of Formula I or a pharmaceutically acceptable salt thereof in a pharmaceutically acceptable carrier; wherein the peptide of formula X1-c[X2-X3-Phe-X4]-X5 is administered in place of, and as a substitute for an opioid to which the subject is addicted. X1 is Tyr or 2,6-Dmt; X2 is an acidic or basic D-amino acid; X3 is Trp or Phe; there is an amide bond between the sidechains of X2 and X4; X5 is NHR (R=H or alkyl) or an amino acid amide. When X2 is an acidic D-amino acid, X4 is a basic amino acid, X3 is Phe, and X5 is NHR; and when X2 is a basic D-amino acid, X4 is an acidic amino acid, and X3 is Trp.

Abstract: The invention relates to cyclic peptide agonists that bind to the mu (morphine) opioid receptor and their use in the treatment of acute and/or chronic pain. Embodiments of the invention are directed to cyclic analogs of endomorphin. These peptide analogs exhibit decreased tolerance relative to morphine, increased solubility compared to similar tetrapeptide analogs, while maintaining favorable or improved therapeutic ratios of analgesia to side effects.

Abstract: The invention relates to cyclic peptide agonists that bind to the mu (morphine) opioid receptor and their use in the treatment of acute and/or chronic pain. Embodiments of the invention are directed to cyclic pentapeptide and hexapeptide analogs of endomorphin that have (i) a carboxy-terminal extension with an amidated hydrophilic amino acid and (ii) a substitution in amino acid position 2. These peptide analogs exhibit decreased tolerance relative to morphine, increased solubility compared to similar tetrapeptide analogs, while maintaining favorable or improved therapeutic ratios of analgesia to side effects.

Abstract: The invention relates to cyclic peptide agonists that bind to the mu (morphine) opioid receptor and their use in the treatment of acute and/or chronic pain. Embodiments of the invention are directed to cyclic pentapeptide and hexapeptide analogs of endomorphin that have (i) a carboxy-terminal extension with an amidated hydrophilic amino acid and (ii) a substitution in amino acid position 2, and in some embodiments, a 2?,6?-dimethyltyrosine (Dmt) residue in place of the N-terminal tyrosine residue a position 1. These peptide analogs exhibit increased solubility compared to similar tetrapeptide analogs while maintaining favorable or improved therapeutic ratios of analgesia to side effects.

Abstract: The invention relates to cyclic peptide agonists that bind to the mu (morphine) opioid receptor and their use in the treatment of acute and/or chronic pain. Embodiments of the invention are directed to cyclic analogs of endomorphin. These peptide analogs exhibit decreased tolerance relative to morphine, increased solubility compared to similar tetrapeptide analogs, while maintaining favorable or improved therapeutic ratios of analgesia to side effects.

Abstract: The invention relates to cyclic peptide agonists that bind to the mu (morphine) opioid receptor and their use in the treatment of acute and/or chronic pain. Embodiments of the invention are directed to cyclic pentapeptide and hexapeptide analogs of endomorphin that have (i) a carboxy-terminal extension with an amidated amino acid and (ii) a D-amino acid substitution in position 2. These peptide analogs exhibit decreased tolerance relative to morphine, increased solubility compared to similar tetrapeptide analogs, while maintaining favorable or improved therapeutic ratios of analgesia to side effects.

Abstract: The invention relates to cyclic peptide agonists that bind to the mu (morphine) opioid receptor and their use in the treatment of acute and/or chronic pain. Embodiments of the invention are directed to cyclic pentapeptide and hexapeptide analogs of endomorphin that have (i) a carboxy-terminal extension with an amidated hydrophilic amino acid and (ii) a substitution in amino acid position 2, and in some embodiments, a 2?,6?-dimethyltyrosine (Dmt) residue in place of the N-terminal tyrosine residue a position 1. These peptide analogs exhibit increased solubility compared to similar tetrapeptide analogs while maintaining favorable or improved therapeutic ratios of analgesia to side effects.

Abstract: The invention relates to cyclic peptide agonists that bind to the mu (morphine) opioid receptor and their use in the treatment of acute and/or chronic pain. Embodiments of the invention are directed to cyclic pentapeptide and hexapeptide analogs of endomorphin that have (i) a carboxy-terminal extension with an amidated hydrophilic amino acid and (ii) a substitution in amino acid position 2. These peptide analogs exhibit decreased tolerance relative to morphine, increased solubility compared to similar tetrapeptide analogs, while maintaining favorable or improved therapeutic ratios of analgesia to side effects.

Abstract: The invention relates to cyclic peptide agonists that bind to the mu (morphine) opioid receptor and their use in the treatment of acute and/or chronic pain. Embodiments of the invention are directed to cyclic pentapeptide and hexapeptide analogs of endomorphin that have (i) a carboxy-terminal extension with an amidated hydrophilic amino acid and (ii) a substitution in amino acid position 2. These peptide analogs exhibit decreased tolerance relative to morphine, increased solubility compared to similar tetrapeptide analogs, while maintaining favorable or improved therapeutic ratios of analgesia to side effects.

Abstract: This invention relates to certain peptides and linear and cyclic analogs thereof that bind to the mu (morphine) opiate receptor with higher affinity, selectivity and potency than currently available peptides. This invention also relates to pharmaceutical preparations containing an effective amount of the peptides or salts thereof, and methods for providing analgesia, relief from gastrointestinal disorders such as diarrhea, and therapy for drug dependence containing a pharmaceutically effective amount of the peptides.

Abstract: This invention relates to certain peptides and linear and cyclic analogs thereof that bind to the mu (morphine) opiate receptor with higher affinity, selectivity and potency than currently available peptides. This invention also relates to pharmaceutical preparations containing an effective amount of the peptides or salts thereof, and methods for providing analgesia, relief from gastrointestinal disorders such as diarrhea, and therapy for drug dependence containing a pharmaceutically effective amount of the peptides.