More Effective Drug Testing: Tools, Interpretation, and Challenges. Pharmacodynamics. Pharmacokinetics. Dose Blood Receptors Effects

Transcription

1 More Effective Drug Testing: Tools, Interpretation, and Challenges Dr. Leo Kadehjian Palo Alto, California Pharmacokinetics Pharmacodynamics Dose Blood eceptors Effects Absorption Distribution Metabolism Elimination Urine, sweat, oral fluid, hair, Correlating Test esults to Effects: What Can Be Said? Body fluid levels Blood levels Brain levels eceptor levels Likelihood of impairment Degree of impairment 1

2 orensic Challenges: Specimens, Technologies Urine: Adulteration, substitution, dilution, interpretation Oral fluid: Adulteration, interpretation On-site: Subjectivity, performance Hair: Contamination, bias, ADA, standards Sweat: Contamination, tampering, standards Oculomotor: Science, standards orensic Issues for Laboratories / Toxicologists Admissibility of evidence Legal standards: peer review, known error rate, standards, Evidentiary weight Chain of custody, laboratory performance, interpretation, Legal requirements for decisionmaking Beyond a reasonable doubt, preponderance, Laboratory liability Duty owed, negligence, privacy of records/hipaa Expert liability Peer oversight 1% Beyond a reasonable doubt 5% Preponderance of the evidence Probable cause easonable suspicion % Mere suspicion Dowling,

3 Non-Users Users Test + alse + True + Unconfirmed + Test - alse - True - Qualitative (positive, negative) vs. Quantitative (ng/ml, immunoreactive equivalents, rate units) vs. Semi-quantitative (no such thing?) Antibody Specificity: Cross-eactivity Antigen Antibody Cross-reactants No cross-reactivity 3

4 Assay response Positive sample Cut-off Negative sample Estimated concentration Cut-off Estimated concentration Derivatized sample Gas Chromatography / Mass Spectrometry Column Detector Carrier gas Oven Gas chromatogram + Ion detector Ionizer Charge / mass separation Mass spectrum Cutoff Level established administratively at or above which a result is reported as positive and below which is reported as negative Limit of Quantitation (LOQ) Level at which a result may be reported as a quantitative value (e.g. ng/ml) with acceptable accuracy (e.g. ±95%) Limit of Detection (LOD) Level at which a result can be clearly distinguished from the range of results for drug-free specimens 4

5 LOD / LOQ / Cutoff Concentration Drug-free Limit of Detection (LOD) Limit Cutoff of (Administrative) Quantitation (LOQ) NIDT 538 (34%) GC/MS Standard cutoffs GC/MS LOD L. Kadehjian, 21 Confirmation of Syva apidtest Initial Cannabinoid Positive Specimens 1% 9% 8% 7% 6% 5% 4% 3% 2% 1% % n= 986 initial positives from rench Gendarmerie medical fitness exams Lowering confirmation cutoff from 15 to 5 ng/ml: Confirmed positives increased+25.2% Confirmation cutoff, ng/ml Y. Lecompte et al., 212 5

6 San Mateo County "Truth in Testing" Standard immunoassay screening cutoffs DA-cleared immunoassay screening device Limit of quantitation GC/MS confirmation testing ederally-certified (SAMHSA) laboratory Established scientific methods and procedures egulatory recognition (SAMHSA policy) Case law support Non-users Immunoassay screen " " " " " " " " " " " " " " " " Users Positive Confirmation (GC/MS) Negative Unconfirmed " " " " Confirmed Positive SAMHSA Drug Presence Criteria Mandatory Guidelines for ederal Workplace Drug Testing Programs Subpart B--Scientific and Technical equirements Section 2.4 Laboratory Analysis Procedures (j) etesting a Specimen for Drugs. (2) Because some drugs or drug metabolites may deteriorate during storage, the retest of an aliquot of a single specimen or the test of a split (Bottle B) specimen is not subject to a specific drug cutoff requirement, but must provide data sufficient to confirm the presence of the drug or metabolite. SAMHSA, , 4/13/4 6

7 U.S. v. Klimek (SDNY, 3/2/4) Drug use violation of supervised release Positive on-site immunoassay (3 ng/ml cut-off) Negative laboratory screening immunoassay (181 ng/ml) Negative GC/MS confirmation (118 ng/ml BE) Creatinine 29.6 mg/dl s.g. 1.3 = diluted, invalid U.S. v. Klimek (SDNY, 3/2/4) The results of a drug test shall be subject to confirmation only if the results are positive, A drug test confirmation shall be a urine drug test confirmed using gas chromatography/mass spectrometry techniques 18 U.S.C. 3563(e) (probation) 18 U.S.C. 3583(d) (supervised release) The program shall include such standards and guidelines as the Director may determine necessary to ensure the reliability and accuracy of the drug testing programs 18 U.S.C. 368 P.L Violent Crime Control and Law Enforcement Act of 1994 U.S. v. Klimek (SDNY, 3/2/4) However, the test result did not mean that Klimek did not have cocaine in his system. Here, a GC/MS test was performed, and it confirmed that cocaine metabolite was present in Klimek s system. It should go without saying that it violates the terms of Klimek s supervised release to have ANY cocaine metabolite in his system. Even if I assume that the fixing of a cut-off level for GC/MS represents the Director s conclusion that Klimek s test result is questionable, that is simply a factor going to the weight of the drug testing evidence before me. 7

8 U.S. v. Klimek (SDNY, 3/2/4) there is nothing magical about the cut-off level selected by the AO; equally reputable organizations involved in drug testing specify lower cut-off levels. The results of the specimen validity test strongly suggest an effort to beat the test and are most persuasively interpreted in that way. And because I find that the results of the GC/MS test conducted on Klimek s urine sample satisfy the Congressionallymandated requirement that a contested drug test be confirmed using GC/MS U.S. v. Klimek, 2nd Cir., 6/8/5 Even more significantly, the confirmation test performed on defendant s sample once it was normalized for dilution would have evinced a cocaine metabolite concentration of 46 nanograms per milliliter, well above the cutoff level of 15 nanograms per milliliter. U.S. v. Klimek, 2nd Cir., 6/8/5 We need not decide at this time whether Sections 3583(d) and 368 preclude a district court from revoking a defendant s supervised release based solely on a test result that fell below the cutoff level. 8

9 Negative does NOT mean No drug Abused Prescription Drugs Opioids CNS Depressants Morphine, codeine, etc. Oxycodone (OxyContin) Buprenorphine Methadone entanyl Meperidine Propoxyphene Benzodiazepines Non-benzos Barbiturates OTC Ephedrine, etc. Dextromethorphan Antihistamines Stimulants Cocaine Amphetamine Methamphetamine Methylphenidate Other Carisoprodol Ketamine Steroids United States Drug Consumption 4.6% of world population Consumes 2/3 of illicit drug supply Consumes 8% of global opioid supply Consumes 99% of global hydrocodone supply L. Manchikanti and A. Singh, 28 9

10 6 5 % increase Increase in Abuse of Controlled Drugs + 542% New teenager opioid abuse % 12 to 17 yr. olds abusing + 15% Prescriptions + 81% Adults abusing + 14% U.S. Population L. Manchikanti, 26 etail Sales of Opioids (millions of grams) mg/person 329 mg/person +347% Ç HÅ Ç H Å É É Oxycodone +732% Hydrocodone +244% (#1 prescribed drug in U.S.) Codeine -25% Morphine +196% Methadone +1177% Meperidine -28% Hydromorphone +274% entanyl +479% www. deadiversion.usdoj.gov 25 2 Past Year Initiates in Illicit Drug Use 3 Thousands Pain relievers Marijuana É É É É É H H H H H É H É H Tranquilizers É É É Cocaine H H H Stimulants Ç Ç Ç Ç Ç Ç Ç Ç Ç Ç Sedatives Heroin L. Manchikanti, 26 1

11 Abuse Supra-therapeutic use, misuse Therapeutic use Concentration Urine Drug Concentrations (ng/ml): 1,922 Chronic Pain Patients Mean Median ange Amphetamine 1,163 3, ,372 Methamphetamine 15,674 1, ,591 Oxycodone Oxymorphone Hydrocodone Hydromorphone Methadone 7,599 2, ,9 4,93 1, ,36 2,953 1, ,2 1, ,526 4,167 2, ,322 Meperidine Normeperidine 3,86 3,49 1, ,216 1, ,98 E. Cone et al., 28 Amphetamine: Adderall, X Synthesized 1887 d-isomer 3-4x CNS activity vs. l-isomer Dosing: Therapeutic: 5 3 mg (3 19 mg) Abuse: up to 2, mg/d Therapeutic urine concentrations: 5 mg: 62 3,16 ng/ml 1 mg: 3,345 (62 12,191) 2 x 1 mg: 6,76 (1,339 15,359) 2 mg: 2,645 5,948 ng/ml 2 mg x 5 d: 5,739 19,172 ng/ml Abusers urine concentrations: 1, 1, ng/ml atalities: 237, ng/ml (25, 7,) 3% 4% eliminated unchanged (74% in acidic urine, 1% in alkaline urine) 11

12 Urine Levels of Oxycodone Oxycodone, ng/ml n = 2 5 mg oral 64 and 4 ( 24 hr) Baselt and Stewart, mg im n = 9 ~5 1, ( 24 hr) Poyhia et al., mg oral n = 2 1 mg im 2 mg im 2,5 and 75 (5 9 hr) 2,5 1, ( 3 9 hr) 6 8 (2 9 hr) Smith et al., 1995 n = 1 7 mg/day 12, 9 Weinstein and Gaylord, 1979 Utility of Urine Drug Levels Evidence of use ( negative vs. no drug ) Unconfirmed positive vs. false positive Consistency of results with claims of donor enewed use vs. residual Likelihood of dosing scenarios Likelihood of impairment Issues in the Use of Urine Drug Levels Test technology Immunoassay (instrumented vs. non-instrumented GC/MS Laboratory reports Qualitative, quantitative, semi-quantitative Interpretation Use, time of use, dosing, impairment 12

13 Passive Inhalation of Marijuana: Single Exposure Studies oints Space Time esults Max. eference 4 4 small room small van 1 hr.5 hr Neg Neg < 6 ng/ml 11.6 ng/ml Mulé et al., 1988 Niedbala et al., 25 4 small van 1 hr Neg 14.7 ng/ml Niedbala et al., 25 5 small room 4 hr Neg 3.4 ng/ml Niedbala et al., 24 6 small room 1 hr Neg 6.8 ng/ml Law et al., small car.5 hr Neg <2 ng/ml Mørland et al., small room 1 hr Neg <2 ng/ml Perez-eyes et al., 1983? coffee shop 3 hr Neg 8 station wagon 12 small car 1 hr.5 hr Pos (1/23) Pos (3 days) 2 ng/ml öhrich et al., 21 2 ng/ml Perez-eyes et al., ng/ml Mørland et al., 1985 Passive Inhalation of Marijuana: Multiple Exposure Studies oints Space Time esults Max. eference 4 small room 1 hr 3 days Pos (1/27) 2 ng/ml Perez-eyes et al., small room 1 hr 6 days Pos ( 7 hrs) 34.5 ng/ml Cone et al., 1986, small room 2 hr x days Pos (5/17) 32.2 ng/ml erslew et al., small room 1 hr 6 days Pos ( 6 days) 1 ng/ml Cone et al., 1986, 1987 Passive Inhalation of Crack Cocaine Dose Space Time Max. BE levels eference 2 mg 4 x 5 1/2 hr 15 ng/ml Baselt et al., mg 7 x 8 1 hr ng/ml Cone et al., mg 7 x 8 1 hr ng/ml Cone et al., mg sidestream 11 x 15 4 hr 6 ng/ml Cone et al.,

14 Cocaine exposure Test results eference Handle 2 x $1 bills immersed in coca paste Immerse hands in coca paste 72 ng/ml BE ust below 3 ng/ml ElSohly et al., 1991 Immerse fingers, 4% solution 2 drops, 4% solution, back of hand Inhale 4% aerosol, nasal procedure All EMIT negative Kavanagh et al., 1992 Urine Specimen Validity Tests Department of Health and Human Services Substance Abuse and Mental Health Services Administration Mandatory Guidelines for ederal Workplace Drug Testing Programs evised Mandatory Guidelines 4/13/ Effective 11/1/4 1.% 8.% 6.% Drug Use, Dilution, and Detection 9.9% 1, DOT specimens 758 dilute Positive at Limit of Detection Positive at HHS cut-offs 4.% 2.8% 2.% 1.2%.3%.% Dilute Normal (758 controls) s.g. <1.3 and / or creatinine <2 mg/dl National Laboratory Certification Program, Program Document #25,

15 equired Specimen Validity Tests: Urine Creatinine Specific gravity if creatinine <2 mg/dl ph Oxidizing adulterants ( 1) Nitrites, pyridinium chlorochromate, chromium (VI), bleach, iodine, halogens, peroxidase, peroxide, others Additional as needed Adulterated Non-normal constituent Endogenous constituent at non-normal concentration Substituted Invalid Urine Specimen Validity Testing Creatinine <2 mg/dl AND s.g. 1.1 or 1.2 Inconsistent creatinine, specific gravity Nitrite, ph, possible presence of other adulterants Interference Appearance Dilute Creatinine 2 mg/dl but <2 mg/dl AND s.g. >1.1 but <1.3 Creatinine, mg/dl Validity Testing Criteria: Urine 2 Inconsistent = Invalid Dilute Normal 2 Substituted Substituted Inconsistent = Invalid Specific 1.2 gravity 15

16 Dilute SAMHSA creat 2 but <2 and s.g. >1.1 but <1.3 U.S. Courts creat 2 but <15 or s.g. 1.2 or 1.3 Invalid creat <2 and s.g. >1.1 but <1.2 ph 3 but <4.5 creat 2 and s.g. 1.1 ph 9 but <11 s.g. 1.1 or 1.45 Substituted Adulterated creat <2 and s.g. 1.1 or 1.2 ph <3 or 11 Non-normal substance Non-normal level creat <2 ph 4 or >1 Non-normal substance Non-normal level Urine Production ate After Water Loading Urine 6 production 5 rate 4 (ml/min) Drink 1 L water Time (min) E. Baldes and. Smirk, 1934 Urine Production ate After Water Loading Urine production rate (ml/min) Drink 2 L water Time (min) Macallum and Benson,

17 Typical: Creatinine ~15 mg/dl Specific Gravity ~1.25 Dilute x 8 Cut-off: 2 mg/dl 1.3 ng/ml Cut-off B Dilute x 8 Dilution: THC B Hr. B B 2 Dilution: Cocaine 15 ng/ml 1 5 Dilute x 8 Cut-off Hr. 17

18 Effect of Water Loading on Urine Cannabinoid Levels Cannabinoids, ng/ml 8 12 oz. Without water load Cutoff 4 With water load (4 x 1 qt) hr E. Cone et al., 1998 NC: Dilute and Below Cutoff esults Cutoff levels for drugs and drug metabolites. (a) Initial drug testing. (2) At the licensee s or other entity s discretion, as documented in the D program policies and procedures, the licensee or other entity may require the HHS-certified laboratory to conduct special analyses of dilute specimens as follows: (i) If initial validity testing indicates that a specimen is dilute, the HHS-certified laboratory shall compare the responses of the dilute specimen to the cutoff calibrator in each of the drug classes; (ii) If any response is equal to or greater than 5 percent of the cutoff, the HHS-certified laboratory shall conduct confirmatory testing of the specimen down to the LOD for those drugs and/or drug metabolites; (iii) The laboratory shall report the numerical values obtained from this special analysis to the MO. NC, inal ule, , 3/31/8 mg/dl Urine Creatinine B B A AÉ B É B É A É B B A B É B A A AÉ É All n= 22,245 AÉ B Male emale A Non-Hispanic White Non-Hispanic Black É Mexican American Age D. Barr et al., 24 18

19 14 12 Urine Creatinine: Diabetics vs. Normal Population Creatinine, mg/dl Diabetics, n = 1,284 NHANES III, n = 9, Age N. de ine Olivarius et al., 26 D. Barr et al., 25 N NH H 2 O N NH O O H NH 2 + H 2 O O NH Creatine Creatinine 4 3 Effect of Creatine Loading on Urine Creatinine Creatinine mg/dl n = 4 Oral creatine: 2 g/day, 5 days, then 5 g/day, 5 days Before creatine loading During / after creatine loading 2 1 opero-miller et al.,

20 # Subjects % Drug-free If 5% highly dilute 15% Non-zero immunoreactive equivalents Cut-off 1% Positive 5% Positive Double detection rate Immunoreactive equivalents, ng/ml Cannabinoids ng/ml Apr 16-Apr 23-Apr 3-Apr 7-May 14-May 21-May 28-May 4-un 11-un 18-un 25-un 2-ul 9-ul 16-ul ng/mg ng/ml mg/dl Apr Cannabinoids normalized 5 Cannabinoids Creatinine 16-Apr 23-Apr 3-Apr May 14-May 21-May 28-May 4-un un un 25-un 2-ul 9-ul 16-ul 2

21 Adjusting Cannabinoid Levels for Dilution / Concentration ng Cannabinoids / ml mg Creatinine / dl x 1 = ng Cannabinoids mg Creatinine 5 ng Cannabinoids / ml 15 mg Creatinine / dl (normal) x 1 = 33 ng Cannabinoids mg Creatinine 5 ng Cannabinoids / ml 15 mg Creatinine / dl (dilute) x 1 = 333 ng Cannabinoids mg Creatinine enewed Use vs. esidual? Cannabinoids Cut-off // Time Marijuana Detection Times for 6 Immunoassays and GC/MS Low dose ng/ml 15 ng/ml High dose Hr Huestis et al.,

22 8 7 6 ±SE Creatinine Normalized THC-COOH in Chronic Users Normalized THC-COOH ng/ml n = 17 5 doses lifetime use (= daily use for 14 years) Levels normalized to 1 mg/dl creatinine 5/17 (29%) negative 2 ng/ml) w/i 1 week 9/17 (53%) negative w/i 2 weeks 11/17 (65%) negative w/i 3 weeks Days after last use E. Kouri et al., 1999 enewed Use or esidual? With current 5 ng/ml cut-off: Occasional users: positive for 1 2 days, rarely longer Documented chronic users: positive for 2 3 weeks, rarely longer Examine every positive, review intervening negatives Positive after 1 month (conservative) enewed use 5% increase in dilution-adjusted levels after 1 week (conservative) enewed use enewed Use vs. esidual Levels from Prior Use? Issues for consideration: Time: between test results, from claimed last use Drug levels (normalized) Pattern: levels (normalized), time, specimen ratios Specimen validity: dilution, creatinine, normalization Donor claims, history 22