The New Substance Abuse and Mental Health Services Administration Oral Fluid Cutoffs for Cocaine and Heroin-Related Analytes Applied to an Addiction Medicine Setting: Important, Unanticipated Findings with LC-MS/MS

Advances in fentanyl testing

Fentanyl is a synthetic opioid that was approved by the FDA in the late 1960s. In the decades since, non-prescription use of fentanyl, its analogs, and structurally unrelated novel synthetic opioids (NSO) has become a worsening public health crisis. There is a clear need for accessible testing for these substances in biological specimens and in apprehended drugs. Immunoassays for fentanyl in urine are available but their performance is restricted to facilities that hold moderate complexity laboratory licenses. Immunoassays for other matrices such as oral fluid (OF), blood, and meconium have been developed but are not widely available. Point of care tests (POCT), such as lateral flow immunoassays or fentanyl test strips (FTS), are widely available but not approved by the FDA for clinical use. All immunoassays are vulnerable to false positive and false negative results. Immunoassays may or may not be able to detect fentanyl analogs and NSOs. Mass spectrometry (MS) can accurately and reliably measure fentanyl and its major metabolite norfentanyl in urine and oral fluid. MS is available at reference laboratories and large hospitals. Liquid chromatography paired with tandem mass spectrometry (LC-MS/MS) is the most widely used method and has outstanding specificity and sensitivity for fentanyl and norfentanyl. When compared to immunoassays, MS is more expensive, requires more technical skill, and takes longer to result. Newer mass spectrometry methods can measure fentanyl analogs and NSO. Both mass spectrometry assays and immunoassays [in the form of fentanyl test strips (FTS)] have potential use in harm reduction programs.

Comparison of Oral Fluid and Urine for Detection of Fentanyl Use Using Liquid Chromatography with Tandem Mass Spectrometry

BACKGROUND

We compared oral fluid (OF) and urine (UR) for detection of fentanyl (FEN) use in addiction medicine-psychiatry (AMP) clinics.

METHODS

We measured FEN and norfentanyl (NRFEN) in UR with a limit of detection (LOD) of 2.0 µg/L and FEN in OF with an LOD of 0.5 µg/L by LC-MS/MS in 311 paired samples and compared the 2 matrices when higher OF and UR LODs were used.

RESULTS

Urine (UR) detected more FEN use than OF using a LOD of 2.0 µg/L and 0.5 µg/L, respectively. FEN and/or NRFEN were detected in 44 and 59 UR specimens, respectively, and FEN in 46 OF specimens (43 OF+UR+, 3 OF+UR-, 16 OF-UR+, and 249 OF-UR-). In UR there were no instances with FEN positive and NORFEN negative. UR creatinine was <20 mg/dL in the 3 OF+UR- specimen pairs. The median OF/UR analyte concentration ratios in positive sample pairs were 0.23 for OF FEN/UR FEN and 0.02 for OF FEN/UR NRFEN.

CONCLUSIONS

We demonstrate that UR detects more FEN use than OF in an AMP setting when UR FEN and UR NORFEN LODs of 2.0 µg/L are used. OF is less sensitive than UR in detecting FEN use, but is still valuable for cases with low UR creatinine and/or suspected adulteration or substitution of UR. The UR vs OF comparison statistics are greatly impacted by even minimal adjustments of the LOD.

Impact of Fentanyl Use on Buprenorphine Treatment Retention and Opioid Abstinence

OBJECTIVES

There has been a rapid increase in the presence of illicitly manufactured fentanyl in the heroin drug supply. Buprenorphine is an effective treatment for heroin and prescription opioid use disorder; however, little is known about treatment outcomes among people using fentanyl. We compared 6-month treatment retention and opioid abstinence among people initiating buprenorphine treatment who had toxicology positive for heroin compared to fentanyl at baseline.

METHODS

Retrospective cohort study of 251 adult patients initiating office-based buprenorphine treatment who had available toxicology testing across an academic health system between August 2016 and July 2017. Exposure was assessed at baseline before initiating buprenorphine and was categorized as negative toxicology (n = 184) versus fentanyl positive toxicology (n = 48) versus heroin positive toxicology (n = 19).

RESULTS

Six-month treatment retention rates were not different between the fentanyl positive and heroin positive groups [38% (n = 18) vs 47% (n = 9); P = 0.58], or between the fentanyl positive and the negative toxicology group [38% (n = 18) vs 51% (n = 93); P = 0.14]. Opioid abstinence at 6 months among those who had testing did not differ between the fentanyl positive and the heroin positive group [55% (n = 6) vs 60% (n = 6); P = 0.99]. The fentanyl positive group had a lower abstinence rate at 6 months compared to those with negative toxicology at baseline [55% (n = 6) vs 93% (n = 63); P = 0.004]. Mean initial buprenophine dosage did not differ between groups.

CONCLUSIONS

Buprenorphine treatment retention and abstinence among those retained in treatment is not worse between people using fentanyl compared to heroin at treatment initiation. Both groups have lower abstinence rates at 6 months compared to individuals with negative toxicology at baseline. These findings suggest that people exposed to fentanyl still benefit from buprenorphine treatment.

Comparison of Oral Fluid and Urine for Detection of Cocaine Abuse Using Liquid Chromatography with Tandem Mass Spectrometry

BACKGROUND

Requests for urine (UR) and oral fluid (OF) drug testing at our institutions are increasing. However, few studies have assessed the accuracy of each matrix using paired specimens and LC-MS/MS. We compared OF and UR for detection of cocaine (COC) abuse in addiction medicine-psychiatry (AMP) clinics.

METHODS

We measured COC and benzoylecgonine (BZE) in OF (limit of detection (LOD) 2.0 µg/L) and BZE in UR (LOD 5 µg/L) by LC-MS/MS in 258 paired samples, and compared the two matrices when higher UR cutoffs of 25, 50, and 150 µg/L were employed.

RESULTS

UR detected more COC abuse than OF at the LOD (5 µg/L). BZE was detected in 63 UR specimens and COC and/or BZE in 40 OF specimens (29 OF+UR+, 11 OF+UR-, 34 OF-UR+). UR creatinine was lower in OF+UR- specimens. COC and BZE were detected in 88% (35/40) and 75% (30/40) of OF specimens, respectively. OF was equivalent to UR at detecting COC abuse using a 25 µg/L cutoff, and detected more COC abuse than UR using 50 and 150 µg/L cutoffs. The ratio of OF COC/BZE increased with decreasing UR BZE concentrations.

CONCLUSIONS

We demonstrate that OF detects more COC abuse in an AMP setting when UR BZE cutoffs ≥ 50 µg/L are utilized, and that UR creatinine concentrations are significantly lower in specimens positive for COC and/or BZE in OF and negative for BZE in UR. The presence of only COC in OF and low concentrations of UR BZE likely indicates remote use of COC.

Assessment of the Utility of the Oral Fluid and Plasma Proteomes for Hydrocodone Exposure

INTRODUCTION

Non-medical use and abuse of prescription opioids is a growing problem in both the civilian and military communities, with minimal technologies for detecting hydrocodone use. This study explored the proteomic changes that occur in the oral fluid and blood plasma following controlled hydrocodone administration in 20 subjects.

METHODS

The global proteomic profile was determined for samples taken at four time points per subject: pre-exposure and 4, 6, or 168 hours post-exposure. The oral fluid samples analyzed herein provided greater differentiation between baseline and response time points than was observed with blood plasma, at least partially due to significant person-to-person relative variability in the plasma proteome.

RESULTS

A total of 399 proteins were identified from oral fluid samples, and the abundance of 118 of those proteins was determined to be significantly different upon metabolism of hydrocodone (4 and 6 hour time points) as compared to baseline levels in the oral fluid (pre-dose and 168 hours).

CONCLUSIONS

We present an assessment of the oral fluid and plasma proteome following hydrocodone administration, which demonstrates the potential of oral fluid as a noninvasive sample that may reveal features of hydrocodone in opioid use, and with additional study, may be useful for other opioids and in settings of misuse.

Urine is superior to oral fluid for detecting buprenorphine compliance in patients undergoing treatment for opioid addiction

BACKGROUND

Buprenorphine (BUP) is commonly used in opioid agonist medication-assisted treatment (OA-MAT). Oral fluid (OF) is an attractive option for compliance monitoring during OA-MAT as collections are observed and evidence suggests that OF is less likely to be adulterated than urine (UR). However, the clinical and analytical performance of each matrix for monitoring BUP compliance has not been well studied.

METHODS

We collected 260 paired OF and UR specimens. Concentrations of buprenorphine (BUP) and norbuprenorphine (NBUP) were measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS) in each matrix. The glucuronide metabolites and naloxone concentrations were also measured in UR by LC-MS/MS. Medications were reviewed and UR creatinine concentrations were determined.

RESULTS

147/260 specimens (57%) were positive for BUP and/or metabolites in one or both matrices. BUP and/or metabolites were more likely to be detected in UR (p < 0.001). 1 OF specimen and 12 UR specimens were considered adulterated/substituted. The majority of patients prescribed BUP were positive for BUP in UR (97%) as opposed to OF (78%). The detection of undisclosed use approximately doubled in UR.

CONCLUSIONS

UR is the preferred matrix for detecting both buprenorphine compliance and undisclosed use. Clinicians should consider the ease of collection, risk of adulteration and detection of illicit drug use when deciding on an appropriate matrix. If OF testing is clinically necessary, UR should be measured in conjunction with OF at least periodically to avoid false negative BUP results.

Oral Fluid Drug Testing: Analytical Approaches, Issues and Interpretation of Results

With advances in analytical technology and new research informing result interpretation, oral fluid (OF) testing has gained acceptance over the past decades as an alternative biological matrix for detecting drugs in forensic and clinical settings. OF testing offers simple, rapid, non-invasive, observed specimen collection. This article offers a review of the scientific literature covering analytical methods and interpretation published over the past two decades for amphetamines, cannabis, cocaine, opioids, and benzodiazepines. Several analytical methods have been published for individual drug classes and, increasingly, for multiple drug classes. The method of OF collection can have a significant impact on the resultant drug concentration. Drug concentrations for amphetamines, cannabis, cocaine, opioids, and benzodiazepines are reviewed in the context of the dosing condition and the collection method. Time of last detection is evaluated against several agencies' cutoffs, including the proposed Substance Abuse and Mental Health Services Administration, European Workplace Drug Testing Society and Driving Under the Influence of Drugs, Alcohol and Medicines cutoffs. A significant correlation was frequently observed between matrices (i.e., between OF and plasma or blood concentrations); however, high intra-subject and inter-subject variability precludes prediction of blood concentrations from OF concentrations. This article will assist individuals in understanding the relative merits and limitations of various methods of OF collection, analysis and interpretation.

Detection of heroin intake in patients in substitution treatment using oral fluid as specimen for drug testing

BACKGROUND

Detection of heroin use is among the major tasks for drug testing and can be best performed by using 6-acetylmorphine as the target analyte. This study was performed to document analytical findings in oral fluid after OF heroin intake.

METHODS

The samples were from routine drug testing of patients in substitution treatment. The analytical investigation was made with a forensic accredited liquid chromatography-tandem mass spectrometry method.

RESULTS

Out of 2814 samples, from 1875 patients, sent for routine drug testing, 406 contained one or more opiate in the drug screening when applying a cutoff limit of 1 ng/mL neat OF. Out of these 406, 314 had a measured 6-AM concentration in neat OF ≥ 1 ng/mL. The study demonstrated that 6-AM is a viable parameter in oral fluid drug testing with an about 80% sensitivity compared to using morphine and codeine as biomarkers. An additional value of using 6-AM is the confidence in concluding a heroin intake. The 6-AM concentrations varied between 1 and >1000 ng/mL, with a median value of 18.6 ng/mL. Heroin was measured in 35 samples with a median value of 0.72 ng/mL. The positive rate for opiates in urine and OF drug testing was the same, 13.5%, in similar populations of patients.

CONCLUSIONS

6-AM is a preferred parameter in OF drug testing for monitoring heroin use and makes OF drug testing for detecting heroin use more effective than urine drug testing when using highly sensitive mass spectrometry methods.

A validated workflow for drug detection in oral fluid by non-targeted liquid chromatography-tandem mass spectrometry

Oral fluid is recognized as an important specimen for drug testing. Common applications are monitoring in substance abuse treatment programs, therapeutic drug monitoring, pain management, workplace drug testing, clinical toxicology, and driving under the influence of drugs (DRUID). In this study, we demonstrate that non-targeted LC-MS/MS with subsequent compound identification by tandem mass spectral library search is a valuable tool for comprehensive detection and confirmation of drugs in oral fluid samples. The workflow developed involves solid-phase extraction and chromatographic separation on reversed phase materials. Mass spectrometric detection is accomplished on a quadrupole-quadrupole-time-of-flight instrument operated with data-dependent acquisition control. The workflow was optimized for 500 μl of neat oral fluid collected with the Greiner Bio-One saliva collection system. The fitness of the developed method was tested and proven by analyzing blank and spiked samples as well as 59 authentic patient samples. We could demonstrate that compounds with logP values in the range 0.5-5.5 are efficiently detected at low nanograms per milliliter concentrations. The true positive and true negative rates of automated library search were equal or close to 100%. The beauty of the non-targeted LC-MS/MS approach is the ability to detect compounds hardly included in routinely applied targeted assays, and this was demonstrated by detecting the synthetic opioid U-47700 in two patient samples. Graphical abstract ᅟ.