Measures That Identify Prescription Medication Misuse, Abuse, and Related Events in Clinical Trials: ACTTION Critique and Recommended Considerations

Shifting quality chronic pain treatment measures from processes to outcomes

OBJECTIVE

Misapplication of the 2016 Centers for Disease Control (CDC) opioid prescribing guidelines has led to overem-phasis of morphineequivalent daily dose (MEDD) as a "metric of success" in chronic noncancer pain (CNCP), resulting in unintentional harms to patients. This article reviews CNCP-related guidelines and patient preferences in order to identify pragmatic, patient-centered metrics to assess treatment response and safety in opioid-treated CNCP.

METHODS

We reviewed the clinical (CDC), research (Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials), and implementability-related guidelines (GuideLine Implementability Appraisal), along with relevant patient-identified treatment goals. From these, we summarize a guideline-concordant, patient-centered, implementable set of measures to aid the clinical management of opioid-treated CNCP.

RESULTS

We identify metrics across three domains of care: (1) treatment response metrics, which align with the CNCP care goals (pain intensity, pain interference including function and quality of life, and global impression of change); (2) risk assessment ("safety") metrics, eg, MEDD, benzodiazepine-opioid or naloxone-opioid coprescribing, and severity of mental health disorders, which evaluate the risk-benefit profile of opioid therapy; and (3) adherence ("process") metrics, which assess clinician/patient adherence to the guideline-recommended opioid therapy monitoring practices, eg, the presence of completed treatment agreement or urine toxicology testing. All metrics should be informed by implementability principles, eg, be decidable, executable, and measurable.

CONCLUSIONS

This article summarizes guideline-concordant, patient-centered, implementable metrics for assessing treatment response, safety, and adherence in opioid-treated CNCP. Regardless of which specific treatment guidelines are applied, this approach could help conceptualize and standardize the collection and reporting of CNCP-relevant metrics, compare them across health systems, and optimize care and treatment outcomes in opioid-treated CNCP.

Assessing Opioid Abuse in Chronic Pain Patients: Further Validation of the Prescription Opioid Misuse Index (POMI) Using Item Response Theory

Due the limitations of the previous validations, the purpose of this study was to further validate the Prescription Opioid Misuse Index (POMI) in a larger sample of chronic non-cancer pain (CNCP) patients and to examine differential item functioning (DIF) across sex. Participants (n=225 CNCP patients under long-term opioid therapy) completed patient characteristics, self-reported POMI and DSM-5 prescription opioid use disorder measurements. Reliability and factor structure were assessed using both item response theory and classical test theory. ROC curve analysis was used to establish the optimum cut-off score for detecting the presence of DSM-5 prescription opioid-use disorder. Concurrent validity was also tested. The POMI showed a unidimensional factor structure and acceptable internal consistency (ωcat =0.62). DIF analysis showed that males and females respond similarly to each item of the POMI, supporting unbiased measurement of the latent trait across both groups. A cut-off point of 2 is suggested in order to maximize the accuracy of the instrument as a first-screening tool for opioid misuse (AUC=0.78; p<0.001; CI 95%: 0.72–0.85). Concurrent validity of the POMI was high with DSM-5 moderate to severe opioid-use disorder criteria (OR=7.824, p<0.001). These results indicate that the POMI is a valid and clinically feasible screening instrument for detecting CNCP patients who misuse opioid medications. The short length of the scale could meet the needs of clinical practice as it allows clinicians to precisely identify and monitor prescription opioid misuse in both male and female patients.

Research approaches for evaluating opioid sparing in clinical trials of acute and chronic pain treatments: Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials recommendations

ABSTRACT

Randomized clinical trials have demonstrated the efficacy of opioid analgesics for the treatment of acute and chronic pain conditions, and for some patients, these medications may be the only effective treatment available. Unfortunately, opioid analgesics are also associated with major risks (eg, opioid use disorder) and adverse outcomes (eg, respiratory depression and falls). The risks and adverse outcomes associated with opioid analgesics have prompted efforts to reduce their use in the treatment of both acute and chronic pain. This article presents Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials (IMMPACT) consensus recommendations for the design of opioid-sparing clinical trials. The recommendations presented in this article are based on the following definition of an opioid-sparing intervention: any intervention that (1) prevents the initiation of treatment with opioid analgesics, (2) decreases the duration of such treatment, (3) reduces the total dosages of opioids that are prescribed for or used by patients, or (4) reduces opioid-related adverse outcomes (without increasing opioid dosages), all without causing an unacceptable increase in pain. These recommendations are based on the results of a background review, presentations and discussions at an IMMPACT consensus meeting, and iterative drafts of this article modified to accommodate input from the co-authors. We discuss opioid sparing definitions, study objectives, outcome measures, the assessment of opioid-related adverse events, incorporation of adequate pain control in trial design, interpretation of research findings, and future research priorities to inform opioid-sparing trial methods. The considerations and recommendations presented in this article are meant to help guide the design, conduct, analysis, and interpretation of future trials.

Design and conduct of confirmatory chronic pain clinical trials

The purpose of this article is to provide readers with a basis for understanding the emerging science of clinical trials and to provide a set of practical, evidence-based suggestions for designing and executing confirmatory clinical trials in a manner that minimizes measurement error. The most important step in creating a mindset of quality clinical research is to abandon the antiquated concept that clinical trials are a method for capturing data from clinical practice and shifting to a concept of the clinical trial as a measurement system, consisting of an interconnected set of processes, each of which must be in calibration for the trial to generate an accurate and reliable estimate of the efficacy (and safety) of a given treatment. The status quo of inaccurate, unreliable, and protracted clinical trials is unacceptable and unsustainable. This article gathers aspects of study design and conduct under a single broad umbrella of techniques available to improve the accuracy and reliability of confirmatory clinical trials across traditional domain boundaries.

Assessment of potentially abuse-related events in two phase 3 studies of NKTR-181, a novel opioid analgesic, using the MADDERS® system (Misuse, Abuse, and Diversion Drug Event Reporting System)

Objective: To prospectively evaluate the abuse potential of NKTR-181, a novel opioid analgesic, in two phase 3 clinical trials using a newly developed reporting system: the Misuse, Abuse, and Diversion Drug Event Reporting System (MADDERS®).Methods: SUMMIT-07 was an enriched enrollment randomized withdrawal study that examined the safety and efficacy of NKTR-181 across 12 weeks in opioid-naïve subjects with chronic low back pain. SUMMIT-LTS was a 52 week open-label study in opioid-naïve and experienced subjects with chronic low back pain or noncancer pain rolled over from SUMMIT-07 or enrolled de novo. System evaluations were triggered by adverse events of interest and drug accountability discrepancies signaling potentially abuse-related events. Each event was assigned a primary classification and supplementary classification(s) by investigators and by a blinded, independent committee of substance abuse experts (adjudicators). At the final study visit, investigators administered a survey to subjects to identify overlooked events of interest.Results: Seventy-nine (6.6%) of 1189 subjects were associated with 86 events in SUMMIT-07 and 51 (8.0%) of 638 subjects were associated with 59 events in SUMMIT-LTS. Most events were attributed to "Withdrawal" and, primarily in SUMMIT-07, "Therapeutic Error" (unintentional overuse) or "Misuse" (intentional overuse for a therapeutic purpose) of study medication. Adjudicators identified five possible "Abuse" events (three NKTR-181, two placebo) in SUMMIT-07 and four possible "Abuse" events (all NKTR-181) in SUMMIT-LTS.Conclusions: The MADDERS® system discerns potentially abuse-related events and identified low rates of withdrawal and a low risk of abuse potential, diversion or addiction associated with NKTR-181 in phase 3 trials.