(301 days)
The Omega Laboratories Hair Drug Screening Assay for Methamphetamine (Meth) and 3,4 Methylenedioxymethamphetamine (MDMA) is an in vitro diagnostic test that is intended for the qualitative detection of Methamphetamine (calibrated with Methamphetamine) and MDMA (calibrated with MDMA) at or above 500 pg/mg in human head and body hair. To confirm a screen positive result, a more specific alternate chemical method, such as Gas Chromatography/Mass Spectrometry (GC/MS) operating in the selected ion monitoring (SIM) mode with deuterated internal standards is the preferred method. Professional judgment should be applied to any drug of abuse test result, particularly when presumptive positive results are obtained. This test is intended exclusively for single laboratory use only and is not intended for sale to anyone.
The Omega Laboratories Hair Drug Screening Assays for Methamphetamine_3,4-methylenedioxymethamphetamine (Meth_MDMA) is a test system using ELISA reagents and micro-plate reader for the qualitative detection of Methamphetamine and 3,4- Methylenedioxymethamphetamine (MDMA) in head and body hair samples at or above 500 pg/mg.
Here's a breakdown of the acceptance criteria and study information for the Omega Laboratories Hair Drug Screening Assay for Methamphetamine (Meth) and 3,4-Methylenedioxymethamphetamine (MDMA), based on the provided text:
Acceptance Criteria and Reported Device Performance
| Acceptance Criteria Category | Specific Criteria | Reported Device Performance |
|---|---|---|
| Precision (Intra-assay) | Acceptable, typically %CV of 10% or less for spiked samples. | Methamphetamine: All 11 replicates for 0, 125, 250, 375 pg/mg were negative; all 11 replicates for 625, 750, 875, 1000 pg/mg were positive. (Table 2a) |
| MDMA: All 11 replicates for 0, 125, 250, 375 pg/mg were negative; all 11 replicates for 625, 750, 875, 1000 pg/mg were positive. (Table 2b) | ||
| Precision (Inter-assay) | Acceptable, typically %CV of 10% or less for spiked samples. | Methamphetamine: All 220 replicates for 0, 125, 250, 375 pg/mg were negative; all 220 replicates for 625, 750, 875, 1000 pg/mg were positive. (Table 3a) |
| MDMA: All 110 replicates for 0, 125, 250 pg/mg were negative; 14 negative and 96 positive for 375 pg/mg; all 110 replicates for 625, 750, 875, 1000 pg/mg were positive. (Table 3b) Note on MDMA at 375 pg/mg: "due to the 166% cross-reactivity of MDMA." | ||
| Precision (Intra-assay, Individual Donor) | Acceptable, typically %CV of 15% or less for individual donor replicates. | Demonstrated as acceptable (specific %CV values for individual donor replicates not provided in tables). |
| Agreement with GC/MS (Qualitative) | Substantial agreement with GC/MS confirmation for both head and body hair. | Methamphetamine (n=739): 142 Negative by ELISA and GC/MS (negative); 472 Positive by ELISA and GC/MS (high positive). |
| MDMA (n=418): 142 Negative by ELISA and GC/MS (negative); 260 Positive by ELISA and GC/MS (high positive). (Tables 4a, 4b) | ||
| Handling Discordant Results | Discordant results should be consistent with the 500 pg/mg cutoff. | Discordant results were observed (e.g., ELISA Positive for Meth at GC/MS 159 pg/mg, 184 pg/mg, etc.; ELISA Negative for Meth at GC/MS 778 pg/mg; ELISA Negative for MDMA at GC/MS 557 pg/mg, 563 pg/mg, 778 pg/mg). The document states, "All Discordant results are consistent with drug cutoff value of 500 pg/mg." This implies potential sensitivity/specificity nuances around the cutoff, confirmed by the note that GC/MS confirmation is performed on all presumptive positive screening results. |
| Cross-reactivity | Acceptable specificity with structurally similar compounds, and no interference from unrelated compounds. | Numerous structurally similar compounds showed varying degrees of cross-reactivity (Tables 5a, 5b). Unrelated compounds at 10000 ng/ml (400000 pg/mg) generally showed no interference, with the exception of d,l-N-Desmethylvenlafaxine in the MDMA spike at -50% CO for concentrations greater than 7500 ng/mL. |
| Effect of Interfering Compounds | No false negatives for expected positive results. | No tested non-structurally cross-reactive samples produced a negative result when expected to be positive (Tables 6a, 6b). Structurally related compounds interfered as expected due to cross-reactivity. |
| Calibrator and Control Stability/Traceability | Validation and stability of solutions, traceability to NIST standards. | Study successfully demonstrated validation and stability of solutions and traceability to NIST standards. 1-year expiration for Calibrator Stock Solution validated. |
| Sample Stability (Storage) | Mean variation in Meth or MDMA concentrations |
§ 862.3100 Amphetamine test system.
(a)
Identification. An amphetamine test system is a device intended to measure amphetamine, a central nervous system stimulating drug, in plasma and urine. Measurements obtained by this device are used in the diagnosis and treatment of amphetamine use or overdose and in monitoring levels of amphetamine to ensure appropriate therapy.(b)
Classification. Class II (special controls). An amphetamine test system is not exempt if it is intended for any use other than employment or insurance testing or is intended for Federal drug testing programs. The device is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 862.9, provided the test system is intended for employment and insurance testing and includes a statement in the labeling that the device is intended solely for use in employment and insurance testing, and does not include devices intended for Federal drug testing programs (e.g., programs run by the Substance Abuse and Mental Health Services Administration (SAMHSA), the Department of Transportation (DOT), and the U.S. military).