Antibiotics influence the risk of anti-drug antibody formation during anti-TNF therapy in Chinese inflammatory bowel disease patients.

Aims: The formation of anti-drug antibodies (ADAs) during anti-tumor necrosis factor (anti-TNF) therapy is reported to lead to reducing serum drug levels, which may bring about a loss of response to treatment. Previous research has suggested an association between specific antibiotic classes and ADA formation during anti-TNF therapy. However, there are few studies specifically examining this association in Chinese inflammatory bowel disease (IBD) patients. Therefore, our study aimed to evaluate the possible effect of antibiotic use on ADA formation to anti-TNF therapy in Chinese patients with IBD. Methods: A total of 166 patients with IBD, including 149 with Crohn's disease (CD) and 17 with ulcerative colitis (UC), were included in this retrospective analysis. These patients were initially treated with anti-TNF therapy (infliximab or adalimumab) after January 2018 and reviewed with available ADA levels before October 2023. After univariable analysis of all the variables, a multivariate Cox proportional hazards model was used to assess the association between antibiotic use and ADA development. Results: Among 166 IBD patients treated with infliximab (108/166, 65.1%) or adalimumab (58/166, 34.9%), 31 patients (18.7%) were measured as positive ADA levels. Cox proportional hazard model demonstrated an increased risk of ADA formation in IBD patients who used ß-lactam-ß-lactamase inhibitor combinations (BL-BLIs) (HR = 5.143, 95%CI 1.136-23.270, p = 0.033), or nitroimidazoles (HR = 4.635, 95%CI 1.641-13.089, p = 0.004) during 12 months before the ADA test. On the contrary, a reduced risk was noted in patients treated with fluoroquinolones (HR = 0.258, 95% CI 0.072-0.924, p = 0.037). Moreover, the median serum infliximab or adalimumab concentration in patients with positive ADA levels was significantly lower than that in patients with negative ADA levels (infliximab: 0.30 vs. 1.85 µg/mL, p < 0.0001; adalimumab: 0.45 vs. 7.55 µg/mL, p = 0.0121). Conclusion: ADA development is associated with various antibiotic classes. BL-BLIs and nitroimidazoles might increase the risk of ADA formation during anti-TNF therapy in Chinese IBD patients, while the treatment with fluoroquinolones could probably reduce such risk. There were certain limitations in the retrospective analysis of the study, therefore, the results are just for reference, and other studies are needed to further confirm our findings.

Adalimumab Dose Reduction and Withdrawal in Stable Non-Infectious Pediatric Uveitis: An Open-Label, Prospective, Pilot Study.

PURPOSES: This study investigated the feasibility of adalimumab (ADA) dose reduction and withdrawal strategy in children with stable pediatric non-infectious uveitis (PNIU). METHODS: This open-label prospective pilot trial recruited 18 stable PNIU patients (33 eyes) between two and eighteen years old who were treated with standard doses of ADA (20/40 mg every 2 weeks) plus oral methotrexate. The interval of ADA injection was extended to 4 weeks and followed up for 24 weeks. If the uveitis remained stable, ADA was discontinued and followed up for another 24 weeks. ADA was considered successfully stopped if no relapse occurred during this period. The relapse-free survival rate, best corrected visual acuity (BVCA), anterior chamber cell (ACC), vitritis, macular thickness (MT), and serum ADA levels were evaluated. Approval Number: 2021KYPJ201. ClinicalTrials.gov identifier: NCT05155592. RESULTS: The relapse-free survival rate was 22.2% (4/18) at 48 weeks. 33.3% (6/18) of patients relapsed when ADA was given every 4 weeks, while 44.5% of patients (8/18) relapsed after ADA was stopped. The four patients successfully withdrawn from ADA were all diagnosed with BD. No statistically significant differences (p > 0.05) were observed in BCVA and MT between baseline and final follow-up. The proportion of ACC and vitritis exhibited an upward trend (p < 0.05) during follow-up. Serum ADA gradually decreased to zero during follow-up in both non-recurrence and recurrence groups. CONCLUSIONS: In PNIU children who reached remission for 6 months, ADA dose reduction and withdrawal were associated with a high risk of inflammation recurrence. Timely adjustment of ADA to the last effective dosage frequency can regain control of the inflammation. Detection of ADA serum levels in patients with recurrence may help find the appropriate interval of ADA use.

Non-trough serum drug levels of adalimumab and etanercept are associated with response in patients with psoriatic arthritis.

OBJECTIVES: Up to 40% of psoriatic arthritis (PsA) patients experience first-line Tumour Necrosis Factor inhibitors (TNF-i) failure. Lower serum drug levels (SDL) have been associated with lower response in autoimmune conditions. This study aimed to: (i) establish the relationship between adalimumab (ADL) and etanercept (ETN) SDL and 3-month response; and (ii) identify optimal non-trough SDL thresholds in PsA. METHODS: PsA patients commencing ADL or ETN were recruited to the UK observational study OUTPASS. Patients were seen pre-TNF-i and at 3 months when response was measured, and non-trough serum samples collected. Response was defined according to the PsARC or EULAR criteria. Descriptive statistics and concentration-effect curves established differences in SDL based on response. Receiver operating characteristics and regression identified optimal SDL thresholds. RESULTS: PsA ETN (n = 97) PsARC and EULAR good responders had significantly higher 3-month SDL compared with non-responders (p= 0.006 and p= 0.020 respectively). Non-trough 3-month ETN SDL discriminated PsARC responders from non-responders (AUC = 0.70), with a threshold of 1.8 µg/ml being 63% specific and 69% sensitive. EULAR good and non-/moderate responders were discriminated with an AUC of 0.65 with a threshold of 2.0 µg/ml being 57% specific and 69% sensitive. ADL prescribed (n = 104) EULAR good responders had significantly higher 3-month SDL (p= 0.049). Non-trough 3-month ADL SDL discriminated EULAR good and non-/moderate responders (AUC = 0.63) with a threshold of 3.6 µg/ml being 48% specific and 81% sensitive. CONCLUSION: Higher 3-month SDL were detected in responders. Interventions to optimise SDL may improve treatment response earlier. This study suggests 3-month SDL thresholds which may be useful in clinical practice to optimise treatment response.

Adalimumab serum levels and anti-drug antibodies: associations to treatment response and drug survival in inflammatory joint diseases.

OBJECTIVES: To explore associations between serum adalimumab level, treatment response and drug survival in order to identify therapeutic drug levels for therapeutic drug monitoring of adalimumab. Also, to assess occurrence and risk factors of anti-drug antibody (ADAb) formation. METHODS: Non-trough adalimumab and ADAb levels were measured by automated fluorescence assays in serum collected after 3 months of adalimumab treatment in patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA) or axial spondyloarthritis (axSpA) included in the observational NOR-DMARD study. Treatment response was evaluated after 3 months, and drug survival during long-term follow-up. RESULTS: In 340 patients (97 RA, 69 PsA, 174 axSpA), median adalimumab level was 7.3 mg/l (IQR 4.0-10.3). 33 (10%) patients developed ADAb. Findings were comparable across diagnoses. In RA and PsA, adalimumab levels ≥6.0 mg/l were associated with treatment response (Odds Ratio [OR] 2.2 [95% CI 1.0, 4.4]) and improved drug survival (Hazard Ratio [HR] 0.49 [0.27, 0.80]). In axSpA, a therapeutic level could not be identified, but higher adalimumab levels were associated with response. Factors associated with ADAb formation were previous bDMARD use, no methotrexate comedication and use of adalimumab originator compared with GP2017. CONCLUSION: Higher adalimumab levels were associated with better response and improved drug survival for all diagnoses, with a suggested lower threshold of 6.0 mg/l for RA/PsA. This finding, the large variability in drug levels among patients receiving standard adalimumab dose, and the high proportion of patients developing ADAb, encourages further investigations into the potential role of therapeutic drug monitoring of adalimumab.

Non-trough adalimumab and certolizumab drug levels associated with a therapeutic EULAR response in adherent patients with rheumatoid arthritis.

OBJECTIVES: Interventions aimed at increasing TNF-α inhibitor serum drug levels (SDLs) may improve treatment response; however, previous studies suggesting SDL cut-offs have not accounted for treatment adherence. The aim of this study was to establish the relationship between adalimumab/certolizumab SDLs and EULAR good vs non-/moderate response and to define SDL cut-offs associated with good response in fully adherent patients. METHODS: In a prospective observational study, 475 patients with RA were treated with certolizumab (n = 192) or adalimumab (n = 283). At baseline and 3, 6 and 12 months, patients had 28-joint DAS, self-reported treatment adherence and SDLs measured. Fully adherent patients were analysed as a subgroup. Follow-up data at 3, 6 and 12 months were analysed separately. Median SDLs were compared in good vs non-/moderate response patients and receiver operating characteristics (ROC) curves were used to establish cut-off SDLs. RESULTS: Fully adherent good responders had significantly higher median adalimumab/certolizumab SDLs compared with non-/moderate responders (P = 0.04 and P = 0.0005, respectively). ROC analysis reported 3 month non-trough adalimumab SDLs discriminated good vs non-/moderate response with an area under the curve (AUC) of 0.63 (95% CI 0.52, 0.75), with a cut-off of 7.5 mg/l being 39.1% specific and 80.9% sensitive. Similarly, 3 month non-trough certolizumab SDLs discriminated good vs non-/moderate response with an AUC of 0.65 (95% CI 0.51, 0.78), with a cut-off of 26.0 mg/l being 43.9% specific and 77.8% sensitive. CONCLUSION: In fully adherent patients, higher SDLs are detected in good responders, suggesting that interventions to improve SDLs, such as encouraging adherence, could improve treatment response. The 3 month non-trough SDL cut-offs of 7.5 mg/l for adalimumab and 26.0 mg/l for certolizumab may be useful in clinical practice.

Antiviral activity of mink interferon alpha expressed in the yeast Pichia pastoris.

Many viruses can cause infections in mink, including canine distemper virus, mink enteritis virus, and Aleutian disease virus. Current treatments are ineffective, and these infections are often fatal, causing severe economic losses. As antiviral drugs may effectively prevent and control these infections, recent research has increasingly focused on antiviral interferons. Herein, the gene encoding a mature mink interferon alpha (MiIFN-α) was synthesized according to the P. pastoris preference of codon usage and a recombinant plasmid, pPICZαA-MiIFN-α, was constructed. pPICZαA-MiIFN-α was linearized and transformed into the P. pastoris X33 strain, and zeocin-resistant transformants were selected. Protein expression was induced by methanol. SDS-PAGE and western blot analyses showed that a 25-kDa fusion protein was expressed in the culture supernatant. Antiviral activity of the expressed protein was determined using cytopathic effect inhibition (CPEI). The purified MiIFN-α significantly inhibited the cytopathic effect of vesicular stomatitis virus with a green fluorescent protein (VSV-GFP) in F81 feline kidney cells, with an antiviral activity of 6.4 × 107 IU/mL; it also significantly inhibited MEV replication in F81 cells. MiIFN-α antiviral activity against VSV-GFP was significantly reduced on treatment with pH 4 and pH 10 conditions for 24 h (p < 0.01). Serum MiIFN-α concentrations in rat were measured using enzyme-linked immune-sorbent assay; MiIFN-α concentrations in rat serum peaked at ~36 h after injection. A high dose of MiIFN-α was safe for use. There were no significant differences in body temperature, tissue changes, and lymphocyte, total white blood cell, and central granulocyte counts between the injected and control groups (p > 0.05). These findings lay a foundation for the large-scale production of recombinant MiIFNs.

Nonadherence by Serum Drug Analyses in Resistant Hypertension: 7-Year Follow-Up of Patients Considered Adherent by Directly Observed Therapy.

Background Measurement of serum concentrations of drugs is a novelty found useful in detecting poor drug adherence in patients taking ≥2 antihypertensive agents. Regarding patients with treatment-resistant hypertension, we previously based our assessment on directly observed therapy. The present study aimed to investigate whether serum drug measurements in patients with resistant hypertension offer additional information regarding drug adherence, beyond that of initial assessment with directly observed therapy. Methods and Results Nineteen patients assumed to have true treatment-resistant hypertension and adherence to antihypertensive drugs based on directly observed therapy were investigated repeatedly through 7 years. Serum concentrations of antihypertensive drugs were measured by ultra-high-performance liquid chromatography-tandem mass spectrometry from blood samples taken at baseline, 6-month, 3-year, and 7-year visits. Cytochrome P450 polymorphisms, self-reported adherence and beliefs about medicine were performed as supplement investigations. Seven patients (37%) were redefined as nonadherent based on their serum concentrations during follow-up. All patients reported high adherence to medications. Nonadherent patients expressed lower necessity and higher concerns regarding intake of antihypertensive medication (P=0.003). Cytochrome P450 polymorphisms affecting metabolism of antihypertensive drugs were found in 16 patients (84%), 21% were poor metabolizers, and none were ultra-rapid metabolizers. Six of 7 patients redefined as nonadherent had cytochrome P450 polymorphisms, however, not explaining the low serum drug concentrations measured in these patients. Conclusions Our data suggest that repeated measurements of serum concentrations of antihypertensive drugs revealed nonadherence in one-third of patients previously evaluated as adherent and treatment resistant by directly observed therapy, thereby improving the accuracy of adherence evaluation. Registration URL: https://www.clinicaltrials.gov; unique identifier: NCT01673516.

Development of UHPLC-MS/MS methods to quantify 25 antihypertensive drugs in serum in a cohort of patients treated for hypertension.

We developed three ultra-high pressure liquid chromatography coupled to mass spectrometry detection (UHPLC-MS/MS) methods to quantify 25 antihypertensive drugs in serum samples. Patient-reported drug lists were collected, and drug concentrations were analysed in samples from 547 patients, half with uncontrolled hypertension, and all treated with ≥ 2 antihypertensive drugs. For sample preparation, serum was mixed with deuterated internal standards and acetonitrile and precipitated. Aliquots of the supernatant were injected on UHPLC-MSMS with a C18 reversed phase column. The mobile phase was 0.1 % HCOOH (formic acid) in water and 0.1 % HCOOH in acetonitrile (except in methanol for spironolactone/canrenone) at a flow rate of 0.4 mL/min. The calibrators and internal controls were prepared in Autonorm™. The calibration ranges were wide, and the models were linear or quadratic with squared correlation coefficients ≥ 0.97. The limits of detection and quantification, specificity, carry-over, and matrix effects were acceptable. The accuracy of the internal controls was in the range 85-121 %, and the intermediate precision for all drugs was 4-28 %. The patient-reported antihypertensive drug use and the detected serum drug concentrations were in accordance with that most frequently prescribed nationally. The percent non-detectable level was 5-10 % for bendroflumethiazide, doxazosin, nifedipine, and ramipril. Often the drug dose chosen was lower than the recommended maximum daily dose. We report the maximum (Cmax) and minimum (Cmin) drug concentrations after drug intake. The inter-individual pharmacokinetic variability at Cmin was 18-fold for hydrochlorothiazide, 22-fold for losartan carboxyl acid, 26-fold for amlodipine, 44-fold for candesartan, and 50-fold for valsartan. Our methods are suitable for measuring antihypertensive drugs in patient serum for therapy control.

Directly Measured Adherence to Treatment in Chronic Heart Failure: LEVEL-CHF Registry.

BACKGROUND: Currently, most available data on the medication adherence of patients with chronic heart failure are based on indirect methods. We examined the level of adherence to medical therapy using a direct method - serum drug level testing. METHODS: We carried out a prospective single-centre registry of patients with chronic heart failure (LEVEL-CHF registry), in whom we analysed serum levels of the medications prescribed for the treatment of heart failure: angiotensin converting enzyme inhibitors, angiotensin receptor blockers, beta-blockers and mineralocorticoid receptor antagonists. We labelled a patient as non-adherent if at least one serum level of a prescribed drug was unmeasurable (below the detection limit). Patients with all tested drugs identifiable in serum were labelled as adherent. We enrolled 274 patients (208 men and 66 women) mean age 62 years. RESULTS: 82.5% of patients were adherent and 17.5% non-adherent to prescribed medications. 3.6% were completely non-adherent without any detectable drugs in serum. Patients aged <60 years were more likely to be non-adherent than older patients (OR 2.15). No other clinical or laboratory parameters predicted non-adherence. CONCLUSIONS: A significant proportion of outpatients with chronic heart failure were non-adherent to treatment when assessed by a direct method of serum drug level testing. Non-adherence was more likely in younger patients.

Quantification of serum levels in mice of seven drugs (and six metabolites) commonly taken by older people with polypharmacy.

Polypharmacy (use of ≥ 5 drugs) is common in older people but has minimal preclinical or clinical evidence of safety or efficacy and is associated with adverse outcomes in older people. Drug-drug interactions are poorly understood beyond drug pairs. An efficient and sensitive method to measure multiple serum drugs and metabolites could inform drug dosing in polypharmacy. Development of a sensitive liquid chromatography - tandem mass spectrometry method to simultaneously measure seven drugs and their respective metabolites in serum in a preclinical model of polypharmacy. This method was validated for optimal recovery, matrix effect, limit of quantification (LOQ), inter- and intra-day variability, and carry over. Serum samples from mice (n = 5-6/group) treated with chronic oral doses of three polypharmacy regimens and five monotherapies were screened for drug and metabolite levels (metoprolol, α-hydroxymetoprolol, O-desmethylmetoprolol, omeprazole, 5-hydroxyomeprazole, omeprazole sulphone, acetaminophen, irbesartan, citalopram, oxybutynin, oxycodone, noroxycodone, oxymorphone and tenivastatin). The LOQ for the compounds ranged from 0.05 to 0.1 ng/mL in serum. Recovery, matrix effect, and inter- and intra-day variability peak response were acceptable. No carry over was observed at the concentrations tested. Analytes were detectable in mice treated with these drugs, and differences in drug levels were observed with different polypharmacy and monotherapy regimens. The method is sensitive and robust to measure parent drugs and metabolites simultaneously in the context of polypharmacy. Polypharmacy appeared to affect drug levels in a preclinical model. This model can be used to understand pharmacokinetics of chronic polypharmacy, which could inform prescribing and improve outcomes for older people.

Efficacy of Posaconazole Prophylaxis for Fungal Disease in Hematology Patients Treated With Chemotherapy and Transplantation: An Open-Label, Prospective, Observational Study.

BACKGROUND: Posaconazole (PCZ) is used prophylactically to prevent invasive fungal infections (IFIs) in patients with hematological malignancies. OBJECTIVE: To evaluate the cut-off serum concentration of PCZ for successful IFI prophylaxis in Chinese subjects. PATIENTS AND METHODS: A total of 74 patients treated with induction chemotherapy (n = 10) and allogeneic hematopoietic stem cell transplantation (HSCT) (n = 64), who received PCZ prophylactically as an oral suspension for >7 days, were included in the study. Clinical, radiological, microbiological culture results, and treatment responses were analyzed and drug concentration assays performed. RESULTS: The overall incidence of possible, probable, and proven IFIs was 13.5% (10/74), with five patients in the chemotherapy group and five in the HSCT group. The PCZ serum concentration in most patients (54/63) was in the range of 0.25-1.0 µg/ml, and this concentration range was significantly associated with the success rate of PCZ prophylaxis. A cut-off value of 0.47 µg/ml can be considered as an evaluation index for PCZ prophylaxis. Taking a proton pump inhibitor (PPI) would reduce the PCZ blood concentration, but not affect the IFD breakthrough point. PCZ treatment for hematopoietic malignancy or HSCT patients with a serum concentration of PCZ < 0.47 µg/ml were risk factors for PCZ prophylaxis of IFIs, determined by univariable and multivariable regression analyses. CONCLUSION: The serum concentration of PCZ was related to the incidence of IFIs and a serum concentration of >0.47 µg/ml is highly recommended to avoid IFIs after chemotherapy or HSCT. CLINICAL TRIAL REGISTRATION: Chinese Clinical Trial Registry: ChiCTR1900026294.

Therapeutic drug monitoring of infliximab compared to standard clinical treatment with infliximab: study protocol for a randomised, controlled, open, parallel-group, phase IV study (the NOR-DRUM study).

BACKGROUND: Infliximab (INX) and other tumour necrosis factor inhibitors (TNFi) have revolutionised the treatment of several immune mediated inflammatory diseases. Still, many patients do not respond sufficiently to therapy or lose efficacy over time. The large interindividual variation in serum drug concentrations on standard doses and the development of anti-drug antibodies are thought to be major reasons for treatment failures. Therapeutic drug monitoring (TDM), an individualised treatment strategy based on systematic assessments of serum drug concentrations, has been proposed as a clinical tool to optimise efficacy of INX treatment. TDM seems reasonable both from a clinical and an economical point of view, but the effectiveness of this treatment strategy has not yet been demonstrated in randomised clinical trials. The NORwegian DRUg Monitoring study (NOR-DRUM) aims to assess the effectiveness of TDM, both with regard to the achievement of remission in patients starting INX treatment (part A) as well as to maintain disease control in patients on INX treatment (part B). METHODS: The NOR-DRUM study is a randomised, open, controlled, parallel-group, comparative, multi-centre, national, superiority, phase IV study with two separate parts, NOR-DRUM A and NOR-DRUM B. Patients with rheumatoid arthritis, psoriatic arthritis, spondyloarthritis, ulcerative colitis, Crohn's disease and psoriasis are included. In both study parts participants are randomised 1:1 to either TDM of infliximab (intervention group) or to standard treatment with infliximab without knowledge of drug levels or ADAb status (control group). NOR-DRUM A will include 400 patients starting INX therapy. The primary outcome is remission at 30 weeks. In NOR-DRUM B, 450 patients on maintenance treatment with INX will be included. The primary endpoint is occurrence of disease worsening during the 52-week study period. DISCUSSION: As the first trial to assess the effectiveness, safety and cost-effectiveness of TDM in patients receiving TNFi for a range of immune mediated inflammatory diseases, we hope that the NOR-DRUM study will contribute to the advancement of evidence based personalised treatment with biological medicines. TRIAL REGISTRATION: Clinicaltrials.gov, NCT03074656. Registered on 090317.

Associations between certolizumab pegol serum levels, anti-drug antibodies and treatment response in patients with inflammatory joint diseases: data from the NOR-DMARD study.

OBJECTIVES: To identify a therapeutic target interval for certolizumab pegol drug levels and examine the influence of anti-drug antibodies in patients with inflammatory joint diseases. METHODS: Certolizumab pegol and anti-drug antibody levels were measured in serum samples collected after 3 months of certolizumab pegol treatment in 268 patients with inflammatory joint diseases (116 axial spondyloarthritis, 91 rheumatoid arthritis and 61 psoriatic arthritis) in the NOR-DMARD study. Treatment response was defined by Ankylosing Spondylitis Disease Activity Score Clinically important improvement in axial spondyloarthritis, European League Against Rheumatism good/moderate response in rheumatoid arthritis, and improvement in 28-joint Disease Activity Score of ≥ 0.6 in PsA. Serum drug levels and anti-drug antibodies were analysed using automated in-house assays. RESULTS: Certolizumab pegol serum levels varied considerably between individuals (median (IQR) 32.9 (17.3-43.9) mg/L). Certolizumab pegol level ≥ 20 mg/L was associated with treatment response for the total inflammatory joint disease population, with odds ratio (OR) 2.3 (95% CI 1.2-4.5, P = 0.01) and OR 1.9 (95% CI 1.0-3.5, P = 0.05) after 3 and 6 months of treatment, respectively. For individual diagnoses, this association was most consistent for axial spondyloarthritis, with OR 3.4 (95% CI 1.0-11.1, P < 0.05) and OR 3.3 (95% CI 1.0-10.8, P < 0.05), respectively. Certolizumab pegol level > 40 mg/L was not associated with any additional benefit for any of the diagnoses. Anti-drug antibodies were detected in 6.1% (19/310) of samples and were associated with low certolizumab pegol levels (P < 0.01). CONCLUSIONS: Serum certolizumab pegol levels 20-40 mg/L were associated with treatment response in inflammatory joint diseases. Our study is the first to show this association in axial spondyloarthritis and psoriatic arthritis patients. The results suggest a possible benefit of therapeutic drug monitoring in patients with inflammatory joint disease on certolizumab pegol treatment. TRIAL REGISTRATION: NCT01581294, April 2012.

False-Positive Serum Cocaine Screening Results in Patients Undergoing Evaluation for Renal Transplant.

Drug screening during pre-transplant evaluations can have major implications for patient care, particularly because drug abuse has been associated with poor transplant outcomes. Although urine drug screening is usually preferred, serum testing is available for situations such as anuria due to end stage renal disease. However, there are few studies evaluating serum drug screening in specific populations such as patients undergoing kidney transplant evaluation. All serum drug screens ordered between January 2015 and November 2017 on patients being evaluated for renal transplant were compared against a large population of serum drug screens ordered from other institutions. Cocaine screening and confirmation results were evaluated to determine false positives. Cocaine screens were positive in 23 of 537 (4.3%) pre-transplant samples, and 211 of 5,115 (4.1%) comparison samples. Confirmation testing demonstrated that 14 (60.9%) pre-transplant samples were false positives, which was significantly (P < 0.01) higher than the rate of false positives in the comparison group (47/211, 22.3%). No common medication or other cross-reacting substance could be identified in the pre-transplant cohort to explain the false-positive results. Although serum cocaine screening had a low overall false-positive rate, the proportion of false positives was significantly higher in pre-transplant patients. Given the poor transplant outcomes associated with drug abuse, failure to properly interpret screening results as being false positives could negatively affect patient care. All members of the transplant team should recognize the importance of confirmation testing in this setting, to avoid unintended consequences due to false-positive screening results.

The Assessment of Serum Drug Levels to Diagnose Non-Adherence in Stable Chronic Heart Failure Patients.

BACKGROUND: The aim of our study was to evaluate the prevalence of drug non-adherence in stable chronic heart failure (CHF) patients using serum drug levels (SDL) assessment. METHODS: CHF patients were prospectively enrolled during scheduled outpatient visit. Except standard procedures an unanticipated blood sampling for the SDL assessment was obtained. Analysis was focused on the prescribed heart failure and antihypertensive medication and was performed by liquid chromatography coupled with mass spectrometry. The patient was labelled as non-adherent if at least one of drugs assessed was not found in the serum. In the first half of patients multiple SDL have been evaluated during the follow-up. RESULTS: Eighty one patients were enrolled. The non-adherence was proven in twenty of them (25%). In the subgroup of thirty eight patients with multiple SDL evaluation the non-adherence raised significantly with increasing number of visits assessed together (21% for single visit, 29% for two of three visits assessed together and 34% for all three visits evaluated together, all p < 0.001). CONCLUSION: The non-adherence was proven in significant part of stable CHF patients using SDL assessment. This method seems to be reliable and effective and should be a part of clinical assessment in selected patients with CHF.

Adalimumab drug and antidrug antibody levels do not predict flare risk after stopping adalimumab in RA patients with low disease activity.

OBJECTIVE: To establish whether serum adalimumab (ADA) trough level (ADA-TL) and antidrug antibody (ADA-ab) level predict flare after stopping ADA in established RA patients with long-standing low disease activity. METHODS: From the clinical trial Potential Optimalisation and Effectiveness of TNF-blockers, 210 RA patients stopping ADA, who had been using ADA (40 mg/2 weeks) for >1 year with conventional synthetic DMARDs and who had low disease activity (DAS28 < 3.2, or the rheumatologist's assessment of low disease activity with CRP < 10 mg/l) for at least 6 months prior to stopping, were followed for 1 year. The ADA-TL was measured (by ELISA) 12-17 days after the last ADA injection; if it was low, ADA-abs were measured (by an antigen-binding test). Association between time-to-flare and ADA-TL was evaluated by area under the receiver operating characteristic curve and Cox regression. RESULTS: A total of 106 (51%) patients flared within 1 year after stopping ADA. The area under the receiver operating characteristic curve for flare and ADA-TL was 0.50 (95% CI 0.42-0.58), P = 0.92. The hazard ratio for flare for ADA-TL ⩾ 5 µg/ml (adequate level) vs <5 µg/ml was 0.93 (95% CI: 0.63-1.36) (not significant). Of the 4 patients with high ADA-ab levels, 2 patients (50%) experienced a flare. CONCLUSION: Flare risk within the year following stopping ADA is not predicted by the ADA-TL or ADA-abs assessed at the moment of stopping. TRIAL REGISTRATION: Netherlands Trial Register, http://www.trialregister.nl, NTR3112.

Association of serum olanzapine concentration and cytochrome P450 1A2 gene polymorphisms: a meta-analysis / 上海交通大学学报（医学版）

Objective: To investigate association of cytochrome P450 1A2 (CYP1A2) gene polymorphisms and serum olanzapine concentration. Methods:Key words including “cytochrome P450 CYP1A2”, “genetic polymorphism”, “antipsychotic”, “olanzapine”, “schizophrenia”, and “serum concentration” were used to search in databases, including SinoMed, Wanfang, Weipu, CNKI, PubMed, Embase and Cochrane Library. The search period was limited from the establishment of the database to February 27th, 2018. STATA/SE 12.0 package was applied to conduct statistical analyses. Results: Four studies with a total of 330 schizophrenic patients were included. In the recessive model of CYP1A2 gene -163C>A SNP, patients with A/A genotype had significantly lower olanzapine concentration/dosage ratio (C/D) than patients with C/C or C/A genotype. Conclusion: A/A homozygote of CYP1A2 gene -163C>A SNP is significantly associated with the decreased olanzapine serum concentration.

Determination of Donepezil and Rivastigmine in Human Serum by High-performance Liquid Chromatogra-phy Combined with Mass Spectrum / 中国药师

Objective: To develop an LC-MS/MS method for the determination of donepezil and rivastigmine in human serum. Methods: After protein precipitation with 600μl acetonitrile, the serum samples were analyzed by LC-MS/MS. Using loratadine as the internal standard, a Waters Xselect CSH C18(150 mm×3 mm, 2. 5 μm) column was used with the mobile phase consisting of water (containing 10 mmol·L-1ammonium acetate)-acetonitrile(20 ∶ 80)at a flow rate of 0. 4 ml·min-1with the column temperature at 40 ℃. The ion transitions were performed in a positive electrospray ionization multiple reaction-monitoring mode regarding [M+H] +as the molecular ion peak of donepezil and rivastigmine monitored with m/z 380. 1→m/z 91. 1 and m/z 251→m/z 206. 5, respectively. The internal standard was monitored with m/z 383. 1→m/z 337. 1. Results: The linear range of donepezil and rivastigmine was 0. 5-400 ng·ml-1(r>0. 99) and the lowest quantification limit was 0. 5 ng·ml-1. For donepezil, the intra-day and inter-day RSD was 2. 06% to 12. 51% , the relative error was -6. 60% to 4. 20% , and the relative recovery was ranged from 80. 76% to 96. 17% (RSD<15% ). For rivastigmine, the intra-day and inter-day RSD was 1. 69% to 9. 31% , the relative error was -5. 58% to 5. 20% , and the mean relative recovery was ranged from 96. 69% to 100. 15% (RSD<15% ). For the two compounds, the serum samples were stable at -40℃ for 75 d and kept stable after three repeated freeze-thaw cycles. The prepared samples were stable in the automatic sample injector (4℃) for 5 h (RSD<15% ). Conclusion: The developed assay method can be applied in the therapeutic monitoring and pharmacokinetic study of donepezil and rivastigmine in human serum.

Effects of Combination Therapy With Immunomodulators on Trough Levels and Antibodies Against Tumor Necrosis Factor Antagonists in Patients With Inflammatory Bowel Disease: A Meta-analysis.

BACKGROUND & AIMS: It is not clear whether combination therapy with immunomodulators affects the immunogenicity of tumor necrosis factor (TNF) antagonists in patients with inflammatory bowel disease. We performed a meta-analysis to quantify the effects of combined immunomodulator therapy on the presence of antibodies against TNF antagonists (antidrug antibodies [ADAs]) and trough levels of anti-TNF agents. METHODS: We systematically searched publication databases for studies that reported prevalence of ADAs in patients who received anti-TNF agents. Raw data from studies that met the inclusion criteria were pooled to determine effect estimates. We performed subgroup and metaregression analyses to determine the level of heterogeneity among study outcomes. RESULTS: We analyzed findings from 35 studies that met inclusion criteria (results reported from 6790 patients with inflammatory bowel disease). The pooled risk ratio for formation of ADAs in patients receiving combined therapy with immunomodulators, versus that of patients receiving anti-TNF monotherapy, was 0.49 (95% confidence interval, 0.41-0.59; P < .001). However, the pooled analysis did not demonstrate a significant difference in trough levels of anti-TNF agents between patients with versus without concurrent use of immunomodulators (standardized mean difference, 0.11; 95% confidence interval, 0.19-0.41; P = .47). Subgroup analyses of patients treated with different TNF antagonists revealed no difference in the formation of ADAs (P = .50 for interaction); the protective effect of immunomodulators did not differ with type of drug patients were given (methotrexate vs thiopurines), or assay for ADA. We observed heterogeneity only among studies of patients with ulcerative colitis (I2 = 76%). Funnel plot and Egger test analyses indicated publication bias in the studies (P = .001). CONCLUSIONS: In a meta-analysis of published studies, we associated combined treatment with immunomodulators with reduced risk of formation of antibodies against TNF antagonists in patients with inflammatory bowel disease.