Comparison of 3 Point-of-Care and 2 Automated Urine Buprenorphine Assays for Screening Patients Treated for Chronic Pain

Buprenorphine (BUP), a partial opioid agonist, is used in outpatient settings to treat opioid addiction and manage chronic pain. Patients in these settings are increasingly screened for the presence or absence of BUP in their urine to monitor medication compliance and to detect and deter misuse of this potent drug. We evaluated 3 point-ofcare (POC; ACON, NTB, and ABMC) and 2 automated urine BUP qualitative immunoassays (CEDIA and LZ) for their ability to accurately detect BUP in 52 urine (17 positive/35 negative) samples from patients treated for chronic pain. Sensitivity and specificity of each assay were evaluated in comparison with a liquid chromatographyYtandem mass spectrometry BUP reference method. Overall agreement with liquid chromatographyYtandem mass spectrometry for these 52 samples, many of which contained low levels of BUP and high concentrations of potentially cross- reacting drugs, was 77%, 73%, 65%, 48%, and 85% for ACON, NTB, ABMC, CEDIA, and LZ, respectively. The NTB POC and automated CEDIA assays were able to detect lower BUP levels and had higher sensitivities, 88% and 94%, respectively, compared with the ACON (29%), ABMC (29%), and LZ (53%) assays. However, the NTB POC, CEDIA, and ABMC POC generated a substantial number of false positives, providing considerable lower specificities of 66%, 26%, and 83%, respectively, compared with the ACON POC and automated LZ methods (both 100%). Of the 3 POC assays, ACON demonstrated the best overall performance, allowing reliable detection of BUP above its stated cutoff without interference from other opioid- related compounds.