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AbstractIntroductionMethylated circulating tumour DNA (ctDNA) blood tests for BCAT1/IKZF1(COLVERA) and SEPT9(Epi proColon) are used to detect colorectal cancer (CRC). However, there are no ctDNA assays approved for other gastrointestinal adenocarcinomas. We aimed to characterize BCAT1, IKZF1and SEPT9methylation in different gastrointestinal adenocarcinoma and non-gastrointestinal tumours to determine if these validated CRC biomarkers might be useful for pan-gastrointestinal adenocarcinoma detection.MethodsTissue DNA methylation data from colorectal (COAD, READ), gastroesophageal (ESCA, STAD), pancreatic (PAAD) and cholangiocarcinoma (CHOL) adenocarcinoma cohorts within The Cancer Genome Atlas were used for differential methylation analyses. Clinicodemographic predictors of BCAT1, IKZF1and SEPT9methylation, and the selectivity of hypermethylated BCAT1, IKZF1and SEPT9for colorectal adenocarcinomas in comparison to other cancers were each explored with beta regression.ResultsHypermethylated BCAT1, IKZF1and SEPT9were each differentially methylated in colorectal and gastroesophageal adenocarcinomas. IKZF1was differentially methylated in pancreatic adenocarcinoma. Hypermethylated DNA biomarkers BCAT1, IKZF1and SEPT9were largely stable across different stages of disease and were highly selective for gastrointestinal adenocarcinomas relative to other cancer types.DiscussionExisting CRC methylated ctDNA blood tests for BCAT1/IKZF1and SEPT9might be usefully repurposed for use in other gastrointestinal adenocarcinomas and warrant further prospective ctDNA studies.

The administration of radiolabeled drug candidates is considered the gold standard in absorption, distribution, metabolism, and excretion studies for small-molecule drugs since it allows facile and accurate quantification of parent drug, metabolites, and total drug-related material independent of the compound structure. The choice of the position of the radiolabel, typically 14C or 3H, is critical to obtain relevant information. Sometimes, a biotransformation reaction may lead to cleavage of a part of the molecule. As a result, only the radiolabeled portion can be followed, and information on the fate of the nonlabeled metabolite may be lost. Synthesis and administration of two or more radiolabeled versions of the parent drug as a mixture or in separate studies may resolve this issue but comes with additional challenges. In this paper, we address the questions that may be considered to help make the right choice whether to use a single or multiple radiolabel approach and discuss the pros and cons of different multiple-labeling strategies that can be taken as well as alternative methods that allow the nonlabeled part of the molecule to be followed.SIGNIFICANCE STATEMENTRadiolabeled studies are the gold standard in drug metabolism research, but molecules can undergo cleavage with loss of the label. This often results in discussions around potential use of multiple labels, which seem to be occurring with increased frequency since an increasing proportion of the small-molecule drugs are tending towards larger molecular weights. This review provides insight and decision criteria in considering a multiple-label approach as well as pros and cons of different strategies that can be followed.

BackgroundMutations in the L/M cone opsin gene array cause abnormally high perceived retinal contrast and the development of myopia. Environmental factors may also lead to high visual contrast and cause myopia. Diffusion optics technology (DOT) lenses are designed to reduce contrast signalling in the retina and slow myopia progression.MethodsThe Control of Myopia Using Peripheral Diffusion Lenses Efficacy and Safety Study (CYPRESS, NCT03623074) is a 36-month, multicentre, randomised, controlled, double-masked trial evaluating two investigational spectacle lenses versus control lenses in myopic children aged 6–10, with a planned interim analysis at 12 months. The primary endpoints are change from baseline in axial length (AL) and spherical equivalent refraction (SER).Results256 children (58% female; mean age at screening, 8.1 years) were dispensed spectacles. Across all groups, baseline averages were AL 24.02 mm (SD±0.77 mm), SER −2.01 D (SD±0.9 D) using manifest refraction, and SER −1.94 D (SD±1.0 D) using cycloplegic autorefraction. At 12 months, mean difference in SER progression for test 1 versus control was −0.40 D (p<0.0001), representing a 74% reduction and −0.32 D for Test 2 (p<0.0001), representing a 59% reduction. The difference in AL progression for test 1 versus control was 0.15 mm (p<0.0001) and test 2 versus control was 0.10 mm (p=0.0018).Conclusion12-month results from this ongoing trial demonstrate the safety and effectiveness of DOT spectacles for reducing myopic progression.

ObjectiveNew screening tests for colorectal cancer (CRC) are rapidly emerging. Conducting trials with mortality reduction as the end point supporting their adoption is challenging. We re-examined the principles underlying evaluation of new non-invasive tests in view of technological developments and identification of new biomarkers.DesignA formal consensus approach involving a multidisciplinary expert panel revised eight previously established principles.ResultsTwelve newly stated principles emerged. Effectiveness of a new test can be evaluated by comparison with a proven comparator non-invasive test. The faecal immunochemical test is now considered the appropriate comparator, while colonoscopy remains the diagnostic standard. For a new test to be able to meet differing screening goals and regulatory requirements, flexibility to adjust its positivity threshold is desirable. A rigorous and efficient four-phased approach is proposed, commencing with small studies assessing the test’s ability to discriminate between CRC and non-cancer states (phase I), followed by prospective estimation of accuracy across the continuum of neoplastic lesions in neoplasia-enriched populations (phase II). If these show promise, a provisional test positivity threshold is set before evaluation in typical screening populations. Phase IIIprospective studies determine single round intention-to-screen programme outcomes and confirm the test positivity threshold. Phase IVstudies involve evaluation over repeated screening rounds with monitoring for missed lesions. Phases III and IV findings will provide the real-world data required to model test impact on CRC mortality and incidence.ConclusionNew non-invasive tests can be efficiently evaluated by a rigorous phased comparative approach, generating data from unbiased populations that inform predictions of their health impact.

GSK3640254 is a next-generation maturation inhibitor in development for HIV-1 treatment, with pharmacokinetics (PK) supporting once-daily oral dosing in human. This open-label, nonrandomized, two-period clinical mass balance and excretion study was used to investigate the excretion balance, PK, and metabolism of GSK3640254. Five healthy men received a single intravenous microtracer of 100 μg [14C]GSK3640254 with a concomitant oral nonradiolabeled 200-mg tablet followed by an oral 85-mg dose of [14C]GSK3640254 14 days later. Complementary methods, including intravenous microtracing and accelerator mass spectrometry, allowed characterization of several parameters, including fraction absorbed, fraction escaping gut metabolism, hepatic extraction ratio, and renal clearance. Intravenous PK of GSK3640254 was characterized by low plasma clearance (1.04 l/h), moderate terminal phase half-life (21.7 hours), and low volume of distribution at steady state (28.7 L). Orally dosed GSK3640254 was absorbed (fraction absorbed, 0.26), with a high fraction escaping gut metabolism (0.898) and a low hepatic extraction ratio (0.00544), all consistent with low in vitro intrinsic clearance in liver microsomes and hepatocytes. No major metabolites in human plasma required further qualification in animal studies. Both unchanged parent GSK3640254 and its oxidative and conjugative metabolites were excreted into bile, with GSK3640254 likely subject to further metabolism through enterohepatic recirculation. Renal elimination of GSK3640254 as the parent drug or its metabolites was negligible, with >94% of total recovery of oral dose and >99% of the recovered radioactivity in feces. Altogether, the data suggest that systemically available GSK3640254 was slowly eliminated almost entirely by hepatobiliary secretion, primarily as conjugative and oxidative metabolites.SIGNIFICANCE STATEMENTThe combination of an intravenous 14C microtracer with duodenal bile sampling using EnteroTracker in a human absorption, distribution, metabolism, and excretion study enabled derivation of absorption and first-pass parameters, including fraction absorbed, proportion escaping first-pass extraction through the gut wall and liver, hepatic extraction, and other conventional clinical pharmacokinetic parameters. This approach identified hepatic metabolism and biliary excretion as a major elimination pathway for absorbed drug, which would be overlooked based solely on analyses of plasma, urine, and fecal matrices.

Daprodustat, an oral hypoxia‐inducible factor prolyl hydroxylase inhibitor, is being investigated for treatment of anemia in chronic kidney disease. This phase 1, nonrandomized, 2‐period, crossover study in 6 healthy men characterized the absorption, distribution, and excretion of daprodustat when administered as oral and intravenous (IV) doses of unlabeled and radiolabeled daprodustat ([14C]‐GSK1278863). Tolerability and pharmacokinetic properties of daprodustat, and its 6 metabolites in the systemic circulation, were also evaluated. The mean recovery of radiolabeled daprodustat was ≈95% by day 5, with the majority in feces and minor renal elimination, indicating that daprodustat and metabolites are primarily eliminated via hepatobiliary and fecal routes. Approximately 40% of total circulating radioactivity in plasma following both IV and oral administration was daprodustat; thus, 60% was attributed to metabolites. It was estimated that ≈80% of daprodustat was absorbed across the gastrointestinal tract, and ≈18% cleared by hepatic extraction. Pharmacokinetics were essentially dose proportional, with moderate (≈66%) oral tablet bioavailability. Following IV administration, daprodustat plasma clearance (19.3 L/h) and volume of distribution (14.6 L) were low, suggesting low tissue distribution outside systemic circulation with likely low penetration into tissues. Daprodustat was generally well tolerated, with no deaths or serious or significant adverse events reported.

To investigate the incidence of advanced neoplasia (colorectal cancer or advanced adenoma) at surveillance colonoscopy following removal of non‐advanced adenoma; to determine whether the time interval before surveillance colonoscopy influences the likelihood of advanced neoplasia. Retrospective cohort study. Patients enrolled in a South Australian surveillance colonoscopy program with findings of non‐advanced adenoma during 1999–2016 who subsequently underwent surveillance colonoscopy. Incidence of advanced neoplasia at follow‐up surveillance colonoscopy. Advanced neoplasia was detected in 169 of 965 eligible surveillance colonoscopies (18%) for 904 unique patients (median age, 62.0 years; interquartile range [IQR], 54.0–69.0 years), of whom 570 were men (59.1%). The median interval between the initial and surveillance procedures was 5.2 years (IQR, 4.4–6.0 years; range, 2.0–14 years). Factors associated with increased risk of advanced neoplasia at follow‐up included age (per year: odds ratio [OR], 1.03; 95% CI, 1.01–1.05), prior history of adenoma (OR, 1.48; 95% CI, 1.01–2.15), two non‐advanced adenomas identified at baseline procedure (vone: OR, 1.74; 95% CI, 1.18–2.57), and time to surveillance colonoscopy (OR, 1.21; 95% CI, 1.08–1.37). The estimated incidence of advanced neoplasia was 19% five years after non‐advanced adenoma removal, and 30% at ten years. Increasing the surveillance colonoscopy interval beyond five years after removal of non‐advanced adenoma increases the risk of detection of advanced neoplasia at follow‐up colonoscopy.

Rapid urbanization and the transformations that it brings are raising urgent questions about understanding the African city. This article stresses the value of viewing urban development through a critical lens that focuses on questions surrounding neoliberalism and the state, highlighting how such an approach can provide important insights into the dynamics of informal economic activity. Examining the recent history of Kisekka Market in Kampala, Uganda, it argues that development processes in the informal economy, even when apparently neutral or ostensibly empowering for the urban poor, facilitate forms of accumulation and dispossession that result in the consolidation of political and economic power. The destruction and rebirth of Kisekka Market, despite its changing politics, has consistently benefitted wealthier vendors and external investors, threatened to displace poorer traders and served the interests of President Museveni, the National Resistance Movement (NRM) and their allies. Exploring these dynamics demands addressing traditional political economy questions that must serve as the foundation for analysing the institutions, structures and processes shaping contemporary African cities.

Linerixibat, an oral small-molecule ileal bile acid transporter inhibitor under development for cholestatic pruritus in primary biliary cholangitis, was designed for minimal absorption from the intestine (site of pharmacological action). This study characterized the pharmacokinetics, absorption, metabolism, and excretion of [14C]-linerixibat in humans after an intravenous microtracer concomitant with unlabeled oral tablets and [14C]-linerixibat oral solution. Linerixibat exhibited absorption-limited flip-flop kinetics: longer oral versus intravenous half-life (6–7 hours vs. 0.8 hours). The short intravenous half-life was consistent with high systemic clearance (61.9 l/h) and low volume of distribution (16.3 l). In vitro studies predicted rapid hepatic clearance via cytochrome P450 3A4 metabolism, which predicted human hepatic clearance within 1.5-fold. However, linerixibat was minimally metabolized in humans after intravenous administration: ∼80% elimination via biliary/fecal excretion (>90%–97% as unchanged parent) and ∼20% renal elimination by glomerular filtration (>97% as unchanged parent). Absolute oral bioavailability of linerixibat was exceedingly low (0.05%), primarily because of a very low fraction absorbed (0.167%; fraction escaping first-pass gut metabolism (fg) ∼100%), with high hepatic extraction ratio (77.0%) acting as a secondary barrier to systemic exposure. Oral linerixibat was almost entirely excreted (>99% recovered radioactivity) in feces as unchanged and unabsorbed linerixibat. Consistent with the low oral fraction absorbed and ∼20% renal recovery of intravenous [14C]-linerixibat, urinary elimination of orally administered radioactivity was negligible (<0.04% of dose). Linerixibat unequivocally exhibited minimal gastrointestinal absorption and oral systemic exposure. Linerixibat represents a unique example of high CYP3A4 clearance in vitro but nearly complete excretion as unchanged parent drug via the biliary/fecal route.Significance StatementThis study conclusively established minimal absorption and systemic exposure to orally administered linerixibat in humans. The small amount of linerixibat absorbed was eliminated efficiently as unchanged parent drug via the biliary/fecal route. The hepatic clearance mechanism was mispredicted to be mediated via cytochrome P450 3A4 metabolism in vitro rather than biliary excretion of unchanged linerixibat in vivo.

Phase 0 approaches — which include microdosing — evaluate subtherapeutic exposures of new drugs in first-in-human studies known as exploratory clinical trials. Recent progress extends phase 0 benefits beyond assessment of pharmacokinetics to include understanding of mechanism of action and pharmacodynamics. Phase 0 approaches have the potential to improve preclinical candidate selection and enable safer, cheaper, quicker and more informed developmental decisions. Here, we discuss phase 0 methods and applications, highlight their advantages over traditional strategies and address concerns related to extrapolation and developmental timelines. Although challenges remain, we propose that phase 0 approaches be at least considered for application in most drug development scenarios.

The study aim was to investigate the pharmacokinetics of single high doses and repeated therapeutic doses of fluticasone furoate (FF) and batefenterol (BAT; a bifunctional muscarinic antagonist and β2‐agonist) administered in combination (BAT/FF) or as monotherapy. In this open‐label, 6‐period, crossover study of 48 subjects, the treatment sequences were (1) single high‐dose BAT/FF 900/300 μg followed by repeated therapeutic doses of BAT/FF 300/100 μg (once daily for 7 days); (2) single high‐dose BAT 900 μg administered concurrently with FF 300 μg; (3) single high‐dose BAT 900 μg followed by repeated therapeutic‐dose BAT 300 μg; (4) single high‐dose FF 300 μg followed by repeated therapeutic‐dose FF 100 μg; (5) single high‐dose FF 300 μg (magnesium stearate); and (6) single high‐dose FF/vilanterol 300/75 μg. Plasma FF area under the plasma drug concentration‐time curve (AUC) was reduced after single high‐dose BAT/FF versus FF alone (ratio of geometric least squares means: 0.79; 90% confidence interval: 0.75‐0.83). After repeat dosing, FF AUC at the lower therapeutic dosage was similar for BAT/FF and FF (primary endpoint; AUC geometric least squares means: 1.03). Adverse events were minor, the most common being cough. These data support the feasibility of developing BAT/inhaled corticosteroid triple therapy in a single inhaler.

An innovative open-label, crossover clinical study was used to investigate the excretion balance, pharmacokinetics, and metabolism of nemiralisib—an inhaled phosphoinositide 3-kinase delta inhibitor being developed for respiratory diseases. Six healthy men received a single intravenous microtracer of 10 µg [14C]nemiralisib with a concomitant inhaled nonradiolabeled 1000 µg dose followed by an oral 800 µg dose of [14C]nemiralisib 14 days later. Complementary methods including accelerator mass spectrometry allowed characterization of a range of parameters including oral absorption (Fabs), proportion of nemiralisib escaping gut wall metabolism (Fg), hepatic extraction (Eh), fraction of dose absorbed from inhaled dose (Flung), and renal clearance. Intravenous pharmacokinetics of nemiralisib were characterized by low blood clearance (10.0 l/h), long terminal half-life (55 hours), and high volume of distribution at steady state (728 l). Nemiralisib exhibited moderate inhaled and oral bioavailability (38% and 35%) while Flungwas 29%. Absorption and first-pass parameters were corrected for blood renal clearance and compared with values without correction. Any swallowed nemiralisib was relatively well absorbed (Fabs, 0.48) with a high fraction escaping gut wall metabolism and low extraction by the liver (Fgand Ehbeing 0.83 and 0.10, respectively). There were no major human plasma metabolites requiring further qualification in animal studies. Both unchanged nemiralisib and its oxidative/conjugative metabolites were secreted in bile, with nemiralisib likely subject to further metabolism through enterohepatic recirculation. Direct renal clearance and metabolism followed by renal clearance were lesser routes of elimination.SIGNIFICANCE STATEMENTA number of innovative features have been combined into one small clinical study enabling a comprehensive description of the human pharmacokinetics and metabolism of an inhaled molecule. Design elements included an intravenous 14C tracer administration concomitant with an inhalation dose that enabled derivation of parameters such as fraction absorbed (Fabs), the proportion of drug escaping first-pass extraction through the gut wall and liver (Fgand Fh) and hepatic extraction (Eh). Entero-test bile sampling enabled characterization of biliary elimination pathways.

Phase 0 approaches, including microdosing, involve the use of sub-therapeutic exposures to the tested drugs, thus enabling safer, more-relevant, quicker and cheaper first-in-human (FIH) testing. These approaches also have considerable potential to limit the use of animals in human drug development. Recent years have witnessed progress in applications, methodology, operations, and drug development culture. Advances in applications saw an expansion in therapeutic areas, developmental scenarios and scientific objectives, in, for example, protein drug development and paediatric drug development. In the operational area, the increased sensitivity of Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS), expansion of the utility of Positron Emission Tomography (PET) imaging, and the introduction of Cavity Ring-Down Spectroscopy (CRDS), have led to the increased accessibility and utility of Phase 0 approaches, while reducing costs and exposure to radioactivity. PET has extended the application of microdosing, from its use as a predominant tool to record pharmacokinetics, to a method for recording target expression and target engagement, as well as cellular and tissue responses. Advances in methodology include adaptive Phase 0/Phase 1 designs, cassette and cocktail microdosing, and Intra-Target Microdosing (ITM), as well as novel modelling opportunities and simulations. Importantly, these methodologies increase the predictive power of extrapolation from microdose to therapeutic level exposures. However, possibly the most challenging domain in which progress has been made, is the culture of drug development. One of the main potential values of Phase 0 approaches is the opportunity to terminate development early, thus not only applying the principle of ‘kill-early-kill-cheap’ to enhance the efficiency of drug development, but also obviating the need for the full package of animal testing required for therapeutic level Phase 1 studies. Finally, we list developmental scenarios that utilised Phase 0 approaches in novel drug development.

Inhaled batefenterol is an investigational bifunctional molecule for the treatment of chronic obstructive pulmonary disease. The excretion balance and pharmacokinetics of batefenterol using [14C]‐radiolabeled drug administered orally and as intravenous (IV) infusion were assessed. In this 2‐period, open‐label study, 6 healthy male subjects received a single IV microtracer 1‐hour infusion of 4 μg [14C]‐batefenterol concomitant with inhaled nonradiolabeled batefenterol (1200 μg) followed by oral [14C]‐batefenterol (200 μg) in period 2 after a 14‐day washout. The primary end points included: the area under the concentration‐time curve from time zero to last time of quantifiable concentration (AUC0‐t); maximum observed concentration (Cmax); and time of occurrence of maximum observed concentration. Following IV administration, the geometric mean AUC0‐tof [14C]‐batefenterol was 121.9 pgEq • h/mL; maximum observed concentration and time of occurrence of maximum observed concentration were 92.7 pgEq/mL and 0.8 hours, respectively; absolute oral bioavailability was 0.012%. The mean AUC0‐tratio indicated that [14C]‐batefenterol accounted for 85% of total circulating radioactivity in the plasma initially and declined rapidly following IV administration, but only ∼0.2% of total circulating radioactivity following oral administration. Cumulative mean recovery of total radioactive [14C]‐batefenterol in urine and feces was 6.31% and 77.6%, respectively. Overall, batefenterol exhibited low systemic bioavailability after inhaled and oral administration, and high fecal excretion and low urinary excretion following IV and oral administration.

The article documents the results of a series of investigations undertaken by the Bamburgh Research Project (BRP) within the Inner Ward of Bamburgh Castle, Northumberland between 1997 and 2010, using resistivity, ground penetrating radar survey, and limited excavation. Throughout the course of the investigation around the ruins of the medieval chapel, material evidence was found of Romano-British activity. Furthermore, stone structures of pre-twelfth-century date were revealed. Two phases of a possible early medieval defensive wall were identified beneath the north wall of the current chapel structure, and a stone building was found beneath the main body of the church which may represent part of the church of St Peter, mentioned by Bede.

To provide comparative ocular topography data from a substantial population of East Asian and white eyes.

The article presents insights on the excavation operations and archaeological discoveries at Hoppenwood Bank, a bog near Bamburgh in Northumberland, England. It says that a test-pitting survey was conducted to investigate the former lake in the area by identifying the extent of peat relative to surface topography. In addition, archaeomagnetic analysis made by Sam Harris of Bradford University provides the date for the last firing of the hearth at 4230 BC.

The CAHMgene (Colorectal Adenocarcinoma HyperMethylated), previously LOC100526820, is located on chromosome 6, hg19 chr6:163 834 097–163 834 982. It lacks introns, encodes a long non-coding RNA (lncRNA) and is located adjacent to the gene QKI, which encodes an RNA binding protein. Deep bisulphite sequencing of ten colorectal cancer (CRC) and matched normal tissues demonstrated frequent hypermethylation within the CAHMgene in cancer. A quantitative methylation-specific PCR (qMSP) was used to characterize additional tissue samples. With a threshold of 5% methylation, the CAHMassay was positive in 2/26 normal colorectal tissues (8%), 17/21 adenomas (81%), and 56/79 CRC samples (71%). A reverse transcriptase-qPCR assay showed that CAHM RNA levels correlated negatively with CAHM% methylation, and therefore CAHMgene expression is typically decreased in CRC. The CAHMqMSP assay was applied to DNA isolated from plasma specimens from 220 colonoscopy-examined patients. Using a threshold of 3 pg methylated genomic DNA per mL plasma, methylated CAHMsequences were detected in the plasma DNA of 40/73 (55%) of CRC patients compared with 3/73 (4%) from subjects with adenomas and 5/74 (7%) from subjects without neoplasia. Both the frequency of detection and the amount of methylated CAHMDNA released into plasma increased with increasing cancer stage. Methylated CAHMDNA shows promise as a plasma biomarker for use in screening for CRC.

To evaluate the effect of varying lens and ocular topography parameters on soft contact lens (SCL) fit, using a novel computer spreadsheet model. Although SCLs are worn by more than 100 million ametropes, the factors governing their fitting characteristics are poorly understood.