Aim To undertake a scoping review of pharmacists’ activities in opioid medicines management in primary care settings, including those developed or led by pharmacists, or in which pharmacists were members of broader multi-disciplinary teams; and to collate the activities, models of care and settings, and reported outcomes. Methods The bibliographic databases MEDLINE, EMBASE, International Pharmaceutical Abstracts, CINAHL, SCOPUS and Web of Science were searched. Studies with quantitative evaluation and published in English were eligible. Participants were patients with any pain category or an opioid use disorder, and healthcare providers. Studies originating in hospitals or involving supply functions were not included. Screening of literature and data charting of results were undertaken by two researchers. Results The 47 studies included in the scooping review occurred in primary care settings collated into four categories: general practice or primary care clinics; healthcare organisations; community pharmacies and outreach services. Studies were primarily of opioid use in chronic, non-cancer pain. Other indications were opioid use disorder, cancer and dental pain. Pharmacist activities targeted risk-mitigation, patient and provider education and broader, strategic approaches. Patient-related outcomes included reduced opioid load, improved functionality and symptom management, enhanced access to services and medication-assisted treatments, and engagement in risk-mitigation strategies. Behaviour change of providers was demonstrated. Conclusion The review has identified the significant contribution that pharmacists working in primary care settings can make to minimise harm from opioids. Strategies implemented in isolation have the potential to further reduce adverse clinical outcomes with greater collaboration and coordination, such as opioid stewardship.

The hypercoagulable state observed in COVID-19 could be responsible for morbidity and mortality. In this retrospective study we investigated whether therapeutic anticoagulation prior to infection has a beneficial effect in hospitalized COVID-19 patients. 1154 COVID-19 patients admitted to 6 hospitals in the Netherlands between March and May 2020 were included. We applied 1:3 propensity score matching to evaluate the association between prior therapeutic anticoagulation use and clinical outcome, with in hospital mortality as primary endpoint. 190 (16%) patients used therapeutic anticoagulation prior to admission. In the propensity score matched analyses, we observed no associations between prior use of therapeutic anticoagulation and overall mortality (RR 1.02 (95% CI; 0.80-1.30) or length of hospital stay (7.0 [4-12] vs 7.0 {4-12] days, p=0.69), although we observed a lower risk of pulmonary embolism (RR 0.19 (95% CI; 0.05-0.80). This study shows that prior use of therapeutic anticoagulation is not associated with improved clinical outcome in hospitalized COVID-19 patients.

Growth-differentiation factor 15 (GDF15) is an inflammatory cytokine involved in energy homeostasis. Its circulating levels are acutely increased by the type 2 diabetes medication metformin, resulting in reduced appetite and weight loss. We identified a genetic variant at the GDF15 gene to proxy a small, lifelong increase in circulating GDF15 levels, and leveraged it in colocalization and Mendelian randomization analyses to investigate the effects of chronically elevated GDF15 levels on body mass index (BMI) and type 2 diabetes liability. The results provide human genetic evidence supporting that chronically elevated GDF15 levels increase BMI. There was no genetic evidence to support bi-directional effects, or that chronically elevated GDF15 levels directly affect liability to type 2 diabetes. Our results contrast the BMI lowering effects of an acute increase in GDF15 levels observed after metformin use. These findings have direct implications for informing pharmacological strategies aimed at targeting GDF15 levels for weight loss.

For the treatment of Covid-19 patients with remdesivir, poor renal- and liver function were both exclusion criteria in randomized clinical trials (RCTs) and contra-indication for treatment. Also, nephrotoxicity and hepatotoxicity are reported as adverse events. We retrospectively reviewed renal- and liver functions of covid-19 patients who received remdesivir in the 15 days after treatment initiation. Approximately 20% of the patient population met RCT exclusion criteria. In total, 11% of the patients had a decrease in estimated glomerular filtration rate larger than 10 ml/min/1.73m2. Also, 25% and 35% had increased alanine transaminase and aspartate transaminase levels, respectively. However, serious adverse events were limited. Therefore, contra-indications based on kidney- and liver function should not be absolute for remdesivir treatment in patients with Covid-19 if these functions are monitored regularly.

Abstract: Aims: The diagnosis of drug-induced liver injury (DILI) is relatively complex, involving a wide variety of drugs. The purpose of this study is to use algorithms to quickly screen DILI patients, count incidence rates and find risk factors. Methods: The Adverse Drug Events Active Surveillance and Assessment System-2 was used to extract the data of hospitalized patients in 2019 according to the set standards, then the RUCAM was used to evaluate patients who meet the standards. A retrospective case-control study was conducted according to suspected drugs, length of hospital stay, height and weight matched controls, and logistic regression was used to find risk factors. Results: Among the 156,570 hospitalized patients, 480 patients (499 cases) of DILI were confirmed, and the incidence of DILI was 0.32%. Anti-infective agents, antineoplastic agents, non-steroidal anti-inflammatory drugs (NASIDs) were the major category of causative drugs causing DILI, and the highest incidence of DILI caused by agent of voriconazole. The latency period and hospital stay of patients with cholestasis was relatively long. Patients with hyperlipidemia (AOR: 1.884), cardiovascular disease (AOR: 1.465), pre-existing liver disease (AOR: 1.827) and surgical history (AOR: 1.312) were likely to be risk factors for DILI. Conclusions: The incidence of DILI in hospitalized patients was uncommon (0.32%), and its pathogenic drugs were widely distributed. LiverTox’s information could assist in the diagnosis of DILI. The incidence of DILI in many drugs was seriously underestimated. It is recommended to focus on patients with hyperlipidemia, cardiovascular disease, pre-existing liver disease, and surgical history.

Anti-tumor necrosis factor alpha (TNFα) agents are effective in diseases including Crohn’s disease (CD) but may cause cytopenias. The mechanisms involved in anti-TNFα agents induced thrombocytopenia are scarce. We report a 73-year-old male with Crohn’s disease for which he currently used adalimumab, an anti-TNFα agent. He had received mesalazine and infliximab before the treatment of adalimumab. No comorbidities were present. Routine laboratory tests revealed a deep thrombocytopenia (thrombocytes 24x10*9/L) after which adalimumab was discontinued. Bleeding symptoms included cutaneous hematomas and mild epistaxis. Direct monoclonal antibody-specific immobilization of platelet antigens (MAIPA assay) revealed autoantibodies specific to glycoprotein IIb/IIIa (GPIIb/IIIa) and glycoprotein V (GPV) platelet receptors. There was no bone marrow suppression. Other causes of the thrombocytopenia were ruled out. The platelet count normalized after adalimumab discontinuation. No further interventions were required. Monitoring thrombocyte levels after initiating anti-TNFα agents is recommended, which could lead to prevention of this potential fatal phenomenon.

Aim Oral flucloxacillin may be co-administered with probenecid to increase flucloxacillin concentrations and increase attainment of pharmacokinetic-pharmacodynamic (PK-PD) targets. The aims of this study were to describe outcomes of patients treated with oral flucloxacillin plus probenecid as follow-on therapy from initial intravenous treatment, and to identify optimal dosing regimens when treating infections caused by susceptible Gram-positive organisms. Methods We performed a prospective observational study of adults treated with oral flucloxacillin 1000 mg and probenecid 500 mg 8-hourly (with food) for proven or probable staphylococcal infections. We developed a population pharmacokinetic model of free flucloxacillin concentrations within Monolix, in order to estimate probability of PK-PD target attainment (fT>MIC), and used Monte Carlo simulation to explore optimal dosing regimens. Results The 45 patients (73% male) had a median (range) age of 49 years (20 – 74), weight of 90 kg (59 – 167), fat free mass (Janmahasatian) of 65 kg (38 – 89) and eGFR (CKD-EPI) of 89 mL/min/1.73m2 (41 – 124). The most common infections were osteomyelitis (n=18, 40%) and septic arthritis (n=12, 27%). Forty patients (89%) were cured 30 days after completion of therapy. 10 (22%) experienced nausea which did not require treatment alternation. Free flucloxacillin clearance depended on allometrically-scaled fat free mass, and increased by 1% for each unit increase in eGFR. Conclusion Oral flucloxacillin and probenecid was well-tolerated and efficacious. Patients with higher fat free mass and eGFR may require four times daily dosing and/or therapeutic drug monitoring to ensure PK-PD target attainment.

Background and purpose: Paclitaxel is a widely used anti-neoplastic agent but has low oral bioavailability due to gut extrusion by P-glycoprotein (P-gp). Oral paclitaxel could be more convenient, less resource intensive, and more tolerable than intravenous administration. Encequidar (HM30181A) is a novel, minimally absorbed gut specific P-gp inhibitor. We tested whether administration of oral paclitaxel with encequidar (oPac+E) achieved comparable AUC to intravenous paclitaxel (IVP) 80mg/m2. Experimental approach: We conducted a multi-centre randomised crossover study with two treatment periods. Patients (pts) with advanced cancer received either oral paclitaxel 615mg/m2 divided over three days and encequidar 15mg orally one-hour prior, followed by IVP 80mg/m2, or the reverse sequence. PK blood samples were taken up to day 9 for oPac+E and day 5 for IVP. Key Results: 42 pts were enrolled; 35 completed both treatment periods. AUC0-∞was 5033.5 +/- 1401.1 ng.h/mL for oPac+E and 5595.9 +/- 1264.1 ng.h/mL with IVP. The geometric mean ratio (GMR) for AUC was 89.5% (90% CI 83.9-95.5). Mean absolute bioavailability of oPac+E was 12%. PK parameters did not change meaningfully after 4 weeks administration of oPac+E in an extension study. G3 treatment emergent adverse events occurred in 7 (18%) pts with oPac+E and 2 (5%) with IVP. 75% of pts preferred oPac+E over IVP. Conclusion and Implications: GMR for AUC was within the predefined acceptable range of 80%-125% for demonstrating equivalence. oPac+E is tolerable and there is no evidence of P-gp induction with repeat administration. With further study, oPac+E is a candidate to replace IVP.

Inhaled nebulised unfractionated heparin (UFH) has a strong scientific and biological rationale that warrants urgent investigation of its therapeutic potential in patients with COVID-19. UFH has antiviral effects and prevents the SARS-CoV-2 virus’ entry into mammalian cells. In addition, UFH has significant anti-inflammatory and anti-coagulant properties, which limit progression of lung injury and vascular pulmonary thrombosis. Methods and intervention The INHALEd nebulised unfractionated HEParin for the treatment of hospitalised patients with COVID-19 (INHALE-HEP) meta-trial is a prospective individual patient data analysis of on-going randomised controlled trials and early phase studies. Individual studies are being conducted in multiple countries. Participating studies randomise adult patients admitted to the hospital with confirmed SARS-CoV-2 infection, who do not require immediate mechanical ventilation, to inhaled nebulised UFH or standard care. All studies collect a minimum core dataset. The primary outcome for the meta-trial is intubation (or death, for patients who died before intubation) at day 28. The secondary outcomes are oxygenation, clinical worsening and mortality, assessed in time-to-event analyses. Individual studies may have additional outcomes. Analysis We use a Bayesian approach to monitoring, followed by analysing individual patient data, outcomes and adverse events. All analyses will follow the intention-to-treat principle, considering all participants in the treatment group to which they were assigned, except for cases lost to follow-up or withdrawn. Trial registration, ethics and dissemination The meta-trial is registered at ClinicalTrials.gov ID NCT04635241. Each contributing study is individually registered and has received approval of the relevant ethics committee or institutional review board.

Bariatric or weight-loss surgery is a popular option for weight reduction. Depending on the surgical procedure, gastric changes like decreased transit time and volume and increased pH, decreased absorption surface in the small intestine, decreased exposure to bile acids and enterohepatic circulation, and decreased gastrointestinal transit time may be expected. In the years after bariatric surgery, patients will also substantially lose weight. As a result of these changes, the absorption, distribution, metabolism, and/or elimination of drugs may be altered. The purpose of this article is to report the general influence of bariatric surgery on oral drug absorption, and to provide guidance for dosing of commonly used or high-risk drugs in this special population. Upon oral drug administration, the time to maximum concentration is often earlier and this concentration may be higher with less consistent effects on trough concentrations and exposure. Additionally, prescription of liquid formulations to bariatric patients is supported by some reports, even though the high sugar load of these suspensions may be of concern. Studies on extended release medications result in an unaltered exposure for a substantial number of drugs. Also, studies evaluating the influence of timing after surgery show dynamic absorption profiles. Although for this group a specific advice can be proposed for many drugs, we conclude that there is insufficient evidence for general advices for oral drug therapy after bariatric surgery implying that a risk assessment on a case-by-case basis is required for each drug.

Aims To evaluate the effect of severe chronic obstructive pulmonary disease (COPD) on drug metabolism by comparing the pharmacokinetics of patients with severe COPD with healthy volunteers and using the modified ‘Inje’ drug cocktail. Methods This was a single-centre pharmacokinetic study with 12 healthy participants and 7 participants with GOLD D COPD. Midazolam 1 mg, dextromethorphan 30 mg, losartan 25 mg, omeprazole 20 mg, caffeine 130 mg, and paracetamol 1000 mg were simultaneously administered and intensive pharmacokinetic sampling was conducted over 8 hours. Drug metabolism by CYP3A4, CYP2D6, CYP2C9, CYP2C19, CYP1A2, UGT1A6 and UGT1A9 in participants with COPD were compared with phenotypes in healthy controls. Results The oral clearance (95% CI) in participants with COPD relative to controls was: midazolam 63% (60-67%), dextromethorphan 72% (40-103%), losartan 53% (52-55%), omeprazole 35% (31-39%), caffeine 52% (50-53%), and paracetamol 73% (72-74%). There was a five-fold increase in AUC for omeprazole and approximately two-fold increases for caffeine, losartan, dextromethorphan, and midazolam. The AUC of paracetamol, which is mostly glucuronidated, was increased by about 60%. Conclusion Severe COPD is associated with a clinically significant reduction in drug clearance. This may be greater for cytochrome P450 substrates than for glucuronidated drugs. This supports reduced starting doses when prescribing for patients with severe COPD.

This themed issue follows a meeting held at the Royal College of Physicians in London in November 2019 entitled “Avoiding harm from overprescribing: how to reduce waste and dependence on prescription drugs.” Here we summarize the existing challenges faced by healthcare professionals and attempt to present solutions to the expanding problem associated with a vast therapeutic arsenal and increasing medical complexity.

Aim: Efavirenz is still widely used as the preferred first-line antiretroviral agent in the middle- and low- income countries, including Malaysia. The efavirenz population pharmacokinetic profile among HIV-positive smokers is still unknown. We aimed to assess the association of smoking with efavirenz and the differences in HIV clinical outcomes. Methods: A total of 154 stable HIV-positive patients on efavirenz in northern Malaysia were recruited with a sparse sampling for this multicentre prospective cohort study. The association between smoking and efavirenz pharmacokinetic parameters was determined using the non-linear mixed-effect model (NONMEM). A mixture model of clearance was adopted to describe the metaboliser status because genetic data is unavailable. The effect of smoking on HIV clinical markers (CD4, CD4 / CD8 ratio and viral blips) for at least two years after the antiretroviral initiation was also investigated. Results: Our data were best fitted with a one-compartment mixture model with first-order absorption without lag time. Smoking significantly associated with higher clearance (CL/F) (β = 1.39; 95% confidence interval (CI): 1.07 to 1.91), while weight affected both CL/F and volume (V/F). From the mixture model, 20% of patients were in the slow clearance group, which mimic the genotype distribution of slow metaboliser. An efavirenz dose reduction is not recommended for smokers ≥60kg with normal metabolism rate. Smoking significantly associated with slower normalisation of CD4 and CD4 / CD8 ratio. Conclusion: HIV-positive smokers presented with significantly higher efavirenz clearance and unfavourable clinical outcomes. Close monitoring of adherence and clinical response among smokers is warranted.

Aim: To quantify the utility of the rate-adjusted area under the concentration curve method in increasing the probability of a correct and conclusive outcome of a bioequivalence (BE) trial for highly variable drugs when clearance (CL) varies more than volume of distribution (V). Methods. Data from a large population of subjects were generated with variability in CL and V parameters and used to simulate a two-period, crossover BE trial. The 90% confidence interval for formulation comparison was determined following BE assessment using the area under the concentration curve (AUC) ratio test, and the proposed rate-adjusted AUC ratio method. An outcome of bioequivalent, non-bioequivalent or inconclusive was then assigned in relation to predefined BE limits. Results: We illustrate the utility of the rate-adjusted AUC method for BE testing when CL varies more than V. The approach is expected to enhance the probability of correctly assigning BE or non-BE and to increase study power to further reduce the risk of an inconclusive trial. Conclusions: The rate-adjusted AUC method represents a simple and readily applicable approach to enhance the BE assessment of drug products when CL varies more than V.

Warfarin has existed for more than seven decades and has been the anticoagulant of choice for many thromboembolic disorders. The recent introduction of direct acting oral anticoagulants (DOACs) has however caused a shift in preference by healthcare professionals all over the world. DOACs have been found to be at least as effective as warfarin in prevention of stroke in patients with atrial fibrillation and in treatment of venous thromboembolism. In sub-Saharan Africa, however, the widespread use of DOACs has been hampered mainly by their higher acquisition costs. As the drugs come off patent, their use in sub-Saharan Africa is likely to increase. However, very few trials have been conducted in African settings, and safety concerns will need to be addressed with further study before widespread adoption into clinical practice.

Aim: Two recommendations for hemodialysis in lithium poisoning, one from the Extracorporeal TReatments in Poisoning (EXTRIP) workgroup and a single center retrospective one (Paris), differ. We compared outcomes in lithium poisoning based on these criteria with a primary outcome of worsening neurological symptoms in patients where EXTRIP and Paris criteria were discordant. Methods: Poison center data were queried for lithium poisoned patients for whom hemodialysis was either recommended or performed. Patients were categorized according to EXTRIP and Paris criteria and excluded if the peak lithium concentration was <1.2 mmol/L or if neurological follow-up was unavailable. Comparative analyses were only performed when both criteria could be assessed. Results: 219 patients were analyzed. Paris criteria were applied in 70 and EXTRIP criteria in 178. 42 patients were excluded because Paris criteria could not be applied. When Paris and EXTRIP both supported hemodialysis, 50/57 (88%) of patients who received hemodialysis improved, as did all 3 who did not receive hemodialysis. When Paris and EXTRIP opposed hemodialysis, all non-dialyzed patients did well. Among the 86 patients for whom EXTRIP supported hemodialysis but Paris did not, 4/19 (21%) patients not dialyzed deteriorated (p=0.02; OR=8.7, 95%CI=1.5-51.8), one of whom died. All 8 patients for whom Paris criteria supported hemodialysis but EXTRIP did not were dialyzed and improved. Conclusion: When the EXTRIP and Paris criteria are discordant, EXTRIP criteria outperforms the Paris criteria at identifying potentially ill patients who might benefit from hemodialysis.

Nitrous oxide is an increasingly popular recreational drug. However recurrent or prolonged use can be associated with nitrous oxide toxicity, with numerous reports of harm documented in the literature. Nitrous oxide irreversibly binds and inactivates vitamin B12, which is an important co-factor in metabolic pathways involved in DNA and myelin synthesis. Toxicity is therefore associated with vitamin B12 deficiency-related syndromes, primarily involving haematological and neurological systems. As a ‘legal high’, nitrous oxide use has attracted repeated health warnings from experts. An awareness and understanding of the pathophysiology and management of nitrous oxide toxicity is therefore important for clinicians. We discuss the case of a 29-year old man presenting with nitrous oxide-induced sensorimotor neuropathy and review the existing literature surrounding toxicity.

Inhibition of interleukin 6 (IL-6) signalling has been proposed as a potential cardioprotective strategy for patients with chronic kidney disease (CKD) but the direct renal effects of IL-6 inhibition are not established. A Mendelian randomization (MR) study was performed to investigate the association of genetically proxied inhibition of IL-6 signalling with estimated glomerular filtration rate (eGFR), CKD and blood urea nitrogen (BUN). Inverse variance weighted MR was used as the main analysis, with sensitivity analyses performed using simple median, weighted median and MR-Egger methods. There was no evidence for an association of genetically proxied inhibition of IL-6 signalling (scaled per unit decrease in natural log transformed C-reactive protein) with log eGFR (0.002, 95% confidence interval -0.004 – 0.008), BUN (0.088, 95% confidence interval -0.003 – 0.019) and CKD (odds ratio 1.018, 95% confidence interval 0.899 – 1.153). These findings suggest that inhibition of IL-6 signalling is unlikely to have a direct effect on renal function.