CR665

Selective Kappa‑opioid Receptor Agonist PeptideRx: InvestigationalCompound: Investigational

Also known as: CR 665, CR665, FE‑200665, FE200665

Educational Only — Not medical advice. Consult a qualified clinician before using any peptide.

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Summary

CR665 is a synthetic peptide κ‑opioid receptor agonist designed for peripheral analgesia. It has been evaluated in early‑phase clinical trials for postoperative and visceral pain but is not yet approved.

Mechanism of Action

Peripherally restricted activation of κ‑opioid receptors → analgesia without central opioid effects

Routes of Administration

IntravenousSubcutaneous

Goals & Uses

  • Visceral pain (e.g., irritable bowel syndrome)AnalgesiaLow
  • Pruritus (itch) modulationSymptom ManagementLow
  • Reduced CNS opioid side effectsSafety ProfileModerate
  • Acute postoperative painAnalgesiaModerate
  • Visceral pain reliefAnalgesiaModerate
  • Inflammatory pain reliefAnalgesiaModerate

Contraindications

  • Severe hepatic impairmentOrganModerateLiver function concerns
  • Severe renal impairmentOrganModerateKidney function concerns
  • PregnancyPopulationModeratePotential fetal risk or insufficient safety data
  • Hypersensitivity to kappa-opioid agonistsAllergy/ImmunologyHigh

Adverse Effects

  • Dysphoria (minimal vs central KOR agonists)NeuropsychiatricRare
  • Injection site reactionsLocalUncommon
  • ConstipationGastrointestinalUncommonReduced bowel frequency or difficulty passing stool
  • DiuresisRenalCommon
  • NauseaGastrointestinalCommonFeeling of sickness or urge to vomit
  • DizzinessNeurologicCommonFeeling faint, lightheaded, or unsteady

Drug Interactions

  • Other opioidsModerate
  • CNS depressantsLow
  • CNS depressants (e.g., benzodiazepines)Low
  • Other opioid agonistsModerate

Population Constraints

  • PregnancyReproductive SafetyRelative
  • Pediatrics (<12 y)AgeRelative
  • Pediatric patientsAgeRelative
  • Elderly patientsAgeRelative
  • Pregnant womenReproductiveRelative
  • Severe hepatic impairmentOrgan ImpairmentRelative

Regulatory Status

  • European UnionInvestigationalUnder clinical evaluation; not authorized for marketing.
  • United StatesInvestigationalPhase I/II clinical trials; not FDA‑approved.
  • United KingdomInvestigationalResearch compound; no MHRA approval.

CR665 has not received regulatory approval in any jurisdiction. It has been studied in early-phase clinical trials (Phase I/II) as an investigational compound. Development has been associated with Janssen and academic research groups.

Evidence & Sources

No sources recorded yet.

Frequently Asked Questions

What is CR665?

CR665 is a synthetic peptide κ‑opioid receptor agonist designed for peripheral analgesia. It has been evaluated in early‑phase clinical trials for postoperative and visceral pain but is not yet approved.

What is CR665 used for?

CR665 is educationally associated with: Visceral pain (e.g., irritable bowel syndrome), Pruritus (itch) modulation, Reduced CNS opioid side effects, Acute postoperative pain, Visceral pain relief, Inflammatory pain relief. Educational only — not medical advice.

How is CR665 administered?

Recorded routes of administration: Intravenous, Subcutaneous.

What are the potential side effects of CR665?

Reported adverse effects include: Dysphoria (minimal vs central KOR agonists), Injection site reactions, Constipation, Diuresis, Nausea, Dizziness. This list is not exhaustive — consult a qualified clinician.

Who should avoid CR665?

Recorded contraindications: Severe hepatic impairment, Severe renal impairment, Pregnancy, Hypersensitivity to kappa-opioid agonists. Consult a qualified clinician before use.