SNPMiner Trials by Shray Alag


SNPMiner Trials: Clinical Trial Report


Report for Clinical Trial NCT00418015

Developed by Shray Alag, 2019.
SNP Clinical Trial Gene

Mu-Opioid Receptor Genetic Polymorphism and the Duration of Intrathecal Fentanyl Labor Analgesia. Mu-Opioid Receptor Genetic Polymorphism and the Efficacy of Postoperative Intrathecal Morphine Analgesia

Pharmacogenetics has allowed clinicians to identify associations between an individual's genetic profile and his/her response to drugs. The A118G (c.188A>G)is a single nucleotide polymorphism (SNP) of the mu-opioid receptor (OPRM1). The mutated protein, N40D, appears to increase the binding affinity and potency of beta-endorphin approximately 3-fold. Individuals carrying the variant receptor gene (A118G) may show differences in some of the functions mediated by beta-endorphin action at the altered OPRM1. Combined spinal-epidural (CSE) analgesia is a commonly utilized technique for labor analgesia. Analgesia is initiated with the intrathecal administration of a lipid-soluble opioid (e.g. fentanyl), sometimes combined with a local anesthetic. The mean (± SD) duration of analgesia after intrathecal fentanyl 25 microgram was 89 ± 43 min. The ED50 of intrathecal fentanyl for labor analgesia varies between 14 microgram to 18.2 microgram. The wide variability in the duration of analgesia, as was well the differences in ED50 may result from differences known to affect labor pain (e.g., ethnicity, parity, stage of labor). Another possible explanation for the differences in opioid requirements and duration, as well as incidence of side effects such as itching and nausea/vomiting, is that opioid responsiveness is determined by genetic variability of the µ-opioid receptor. The ED50 for intrathecal fentanyl labor analgesia was significantly lower for parturients carrying the A118G variant of the mu-opioid receptor, compared to parturients with the A118 wild type receptor. The purpose of this study is to determine whether polymorphism at nucleotide 118 of OPRM1 influences the duration of intrathecal opioid (fentanyl) labor analgesia, and intrathecal opioid (morphine) postoperative analgesia.

NCT00418015 Labor Pain Post-cesarean Delivery
MeSH: Labor Pain

1 Interventions

Name: Blood Draw

Description: Blood for OPRM1 analysis

Type: Procedure

Labor analgesia Cesarean delivery analgesia


Primary Outcomes

Description: Time from intrathecal drug administration to request for analgesia either in laboring women of after cesarean delivery

Measure: Duration of Intrathecal Fentanyl Analgesia

Time: Time (0-1440 minutes) to first analgesia request

Description: Time until request for supplemental analgesia following intrathecal morphine/fentanyl for cesarean delivery

Measure: Duration of Intrathecal Analgesia Following Cesarean Delivery

Time: 0 to 72 hours following cesarean delivery

Description: Visual analog pain scale (0 to 100) at 1st request for supplemental analgesia

Measure: Visual Analog Pain Scale (0 to 100) at Analgesia Request Following Intrathecal Intervention

Time: VAS at analgesia request

Secondary Outcomes

Description: Severity of pruritus during labor analgesia

Measure: Severity of Pruritus Following Fentanyl

Time: Labor analgesia

Description: Subjects reporting pruritus in the first 24 hours post cesarean delivery

Measure: Subjects With Pruritus at 24 Hours Post Morphine

Time: 24 hours post cesarean delivery

Time Perspective: Prospective

Cohort


There are 2 SNPs

SNPs


1 A118G

The A118G (c.188A>G)is a single nucleotide polymorphism (SNP) of the mu-opioid receptor (OPRM1). --- A118G ---

Individuals carrying the variant receptor gene (A118G) may show differences in some of the functions mediated by beta-endorphin action at the altered OPRM1. --- A118G ---

The ED50 for intrathecal fentanyl labor analgesia was significantly lower for parturients carrying the A118G variant of the mu-opioid receptor, compared to parturients with the A118 wild type receptor. --- A118G ---

SNP genotyping: For identification of allelic distribution of the A118G SNP, 20-60 ng of DNA from individuals will be first amplified by PCR (on thermocycler apparatuses equipped with a 96 well-microtiter plate block) using primers designed in the vicinity of the SNPs. --- A118G ---


2 N40D

The mutated protein, N40D, appears to increase the binding affinity and potency of beta-endorphin approximately 3-fold. --- N40D ---



HPO Nodes