Effect of Kollidon VA®64 particle size and morphology as directly compressible excipient on tablet compression properties

The study evaluates use of Kollidon VA^®64 and a combination of Kollidon VA^®64 with Kollidon VA^®64 Fine as excipient in direct compression process of tablets. The combination of the two grades of material is evaluated for capping, lamination and excessive friability. Inter particulate void space is higher for such excipient due to the hollow structure of the Kollidon VA^®64 particles. During tablet compression air remains trapped in the blend exhibiting poor compression with compromised physical properties of the tablets. Composition of Kollidon VA^®64 and Kollidon VA^®64 Fine is evaluated by design of experiment (DoE). A scanning electron microscopy (SEM) of two grades of Kollidon VA^®64 exhibits morphological differences between coarse and fine grade. The tablet compression process is evaluated with a mix consisting of entirely Kollidon VA^®64 and two mixes containing Kollidon VA^®64 and Kollidon VA^®64 Fine in ratio of 77:23 and 65:35. A statistical modeling on the results from the DoE trials resulted in the optimum composition for direct tablet compression as combination of Kollidon VA^®64 and Kollidon VA^®64 Fine in ratio of 77:23. This combination compressed with the predicted parameters based on the statistical modeling and applying main compression force between 5 and 15 kN, pre-compression force between 2 and 3 kN, feeder speed fixed at 25 rpm and compression range of 45-49 rpm produced tablets with hardness ranging between 19 and 21 kp, with no friability, capping, or lamination issue.

Urethral involvement of myeloma: A rare case of visible haematuria leading to a diagnosis of relapsed multiple myeloma after curative stem cell transplantation

Extramedullary multiple myeloma involving the urinary tract is extremely rare. We report an unusual case of visible haematuria in a 45-year-old male who had a stem cell transplant for multiple myeloma 18 months previously. Cysto-urethroscopy revealed a mid-urethral lesion that was then fully excised by endoscopic resection. Histology confirmed malignant plasma cell infiltrate with subsequent staging and skeletal biopsy of a rib lesion confirming relapse of multiple myeloma. We believe this is the first case of urethral involvement to reveal a relapse of multiple myeloma after autologous stem cell transplant.

The importance of physical function to people with osteoporosis

There is increasing need to understand patient outcomes in osteoporosis. This article discusses that fracture in osteoporosis can lead to a cycle of impairment, driven by complex psychosocial factors, having a profound impact on physical function/activity which accumulates over time. More information is required on how treatments impact physical function.

INTRODUCTION

There is increasing need to understand patient-centred outcomes in osteoporosis (OP) clinical research and management. This multi-method paper provides insight on the effect of OP on patients' physical function and everyday activity.

METHODS

Data were collected from three sources: (1) targeted literature review on OP and physical function, conducted in MEDLINE, Embase and PsycINFO; (2) secondary thematic analysis of transcripts from patient interviews, conducted to develop a patient-reported outcome instrument. Transcripts were re-coded to focus on OP impact on daily activities and physical function for those with and without fracture history; and (3) discussions of the literature review and secondary qualitative analysis results with three clinical experts to review and interpret the importance and implications of the findings.

RESULTS

Results suggest that OP, particularly with fracture, can have profound impacts on physical function/activity. These impacts accumulate over time through a cycle of impairment, as fracture leads to longer term detriments in physical function, including loss of muscle, activity avoidance and reduced physical capacity, which in turn leads to greater risk of fracture and potential for further physical restrictions. The cycle of impairment is complex, as other physical, psychosocial and treatment-related factors, such as comorbidities, fears and beliefs about physical activity and fracture risk influence physical function and everyday activity.

CONCLUSION

More information on how treatments impact physical function would benefit healthcare professionals and persons with OP in making treatment decisions and improving treatment compliance/persistence, as these impacts may be more salient to patients than fracture incidence.

Outcomes of involuntary hospital admission. Satisfaction with treatment and the effect of involuntary admissions on patients

Introduction

Involuntary hospitalization in those presumed to be mentally ill has been a common practice. Although some patients are hospitalized for aggression, two-thirds of the patients are hospitalized because of the threat they pose to themselves. Although these patients require risk assessment and evaluation for possible presence of mental illness, the question is how much these patients will benefit from involuntary admission and what the long-term outcome would be.

Method

All patients admitted involuntary to the psychiatric ward in Kingston, Canada, and psychiatrists involved in their care were interviewed to see whether they think the involuntary admission was helpful. All patients were asked to fill-out MacArthur AES to assess their satisfaction with hospitalization.

Results

Although psychiatrists frequently reported that the admission was justified, only 29 out of 81 patients reported being explained to why they had been admitted involuntarily. Also, there was a significant difference in AES scores between those who were and were not given an explanation for admission. In addition, psychiatrists more often reported that the involuntary admission worsened the therapeutic relationship which was significantly associated with involuntary admission that was not explained to patients.

Discussion

The results of our study shows that patients admitted involuntarily often feel disappointed with staff and mental health system. It could lead to feeling of hopelessness, frustration and low self-esteem. If explained, some patients who present with risk to self might accept voluntary admissions, that will improve therapeutic alliance with psychiatrists and increase satisfaction from hospitalization. Result of this study could improve the decision making process for involuntary admissions.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Health-related quality of life and work productivity of adults with ADHD: A UK web-based survey

Introduction

European data on health-related quality of life (HRQoL) in adults with attention deficit/hyperactivity disorder (ADHD) in the general population is sparse.

Aims and objectives

To report HRQoL in UK adults with ADHD.

Methods

UK residents aged 18–55 years with a diagnosis of adult ADHD completed an online, cross-sectional survey including questions on disease history, the EuroQol Five Dimensions questionnaire with five-levels (EQ-5D-5L) and the Work productivity and activity impairment questionnaire: general health (WPAI:GH). ADHD symptom severity was assessed by telephone using ADHD rating scale version IV with adult prompts (ADHD-RS-IV).

Results

The survey was completed by 233 participants (65.2% women; 77.3% white British), mean age 32.6 years (standard deviation [SD] 9.5), mean ADHD-RS-IV total score 43.46 (SD 7.88). Their mean EQ-5D-5L utility score of 0.74 (SD 0.21) was lower than the UK population norm of 0.86 (SD 0.23).[1] WPAI:GH scores indicated that health problems resulted in impairments of 32.04% in work productivity and 45.79% in regular daily activities. Regression analyses adjusting for gender, age and comorbidities demonstrated associations between EQ-5D-5L utility scores and gender (men had lower scores, P < 0.001), work impairment due to health problems (increasing impairment was associated with lower scores, P = 0.005) and age (for each additional year of age, scores decreased by 0.007, P = 0.010).

Conclusions

These results highlight the impact on health utility, work productivity and regular daily activities, and add to the description of the disease burden of adult ADHD in the UK.

This study was funded by Shire Development LLC.

Disclosure of interest

Kings College London research support account for Asherson received honoraria for consultancy to Shire, Eli-Lilly and Novartis educational/research awards from Shire, Lilly, Novartis, Vifor Pharma, GW Pharma and QbTech speaker at sponsored events for Shire, Lilly and Novartis.

The resonance® metallic ureteric stent in the treatment of chronic ureteric obstruction: a safety and efficacy analysis from a contemporary clinical series

BACKGROUND

We evaluate the efficacy and safety of metallic ureteric stenting using the Cook Resonance® stent in the treatment of chronic ureteric obstruction of benign and malignant aetiology. Published experience of using this stent in this context is limited. We add to the body of literature on this topic.

METHODS

All patients who had a Resonance® metallic stent inserted between April 2009 and November 2014 in our institution were identified from a prospectively maintained stent-database. Primary outcome was relief of ureteric obstruction, defined by successful clinical and radiological treatment of hydronephrosis/hydroureter. Secondary outcome measures included operative time, radiological exposure, total stent dwell time (defined as the cumulative time in months for which a Resonance® metallic stent was in situ), and early and late complications.

RESULTS

Twenty-one patients underwent 52 stent insertion episodes (SIE). Median age was 58 years (range 39-90). Stent insertion resulted in successful treatment of hydronephrosis/hydroureter in 96% (2 SIE resulted in failure to relieve ureteric obstruction). Median operative time was 21 min (range 12-90) Median radiation exposure was 815.3 cGy/cm2 (range 192.9-5366.3). Median stent dwell time was 19.5 months (range 6-52) in non-malignant and 12 months (range 2-48) in malignant ureteric obstruction. One stent migrated proximally during insertion and had to be retrieved using an antegrade approach. 5 patients re-admitted with haematuria: all resolved without intervention or blood transfusion. 3 episodes of post-operative urinary infection were recorded; all were successfully treated with oral antibiotics.

CONCLUSION

Metallic ureteric stenting using the Resonance® stent is safe and effective for treating ureteric obstruction from both malignant and benign causes. The success rate in our series is 96%.

How do emergency ambulance paramedics view the care they provide to people who self harm?: Ways and means

The UK has one of the highest rates of self harm (SH) in Europe, and almost four times more people die by suicide than in road traffic collisions. Emergency ambulance paramedics are often the first health professionals involved in the care of people who have self-harmed, yet little is known about the care provided or issues raised in these encounters. The aim of this study is to explore paramedics' perceptions and experiences of caring for people who SH, to inform education and policy. Semi structured interviews were conducted with paramedics, and themes generated by constant comparison coding. This paper reports two emerging themes: Firstly, professional, legal, clinical and ethical tensions, linked to limited decision support, referral options and education. The second theme of relationships with police, revealed practices and surreptitious strategies related to care and detention, aimed at overcoming complexities of care. In the absence of tailored education, guidance or support for self-harm care, 'ways and means' have evolved which may negatively influence care and challenge ethical and legal frameworks. There is an urgent need to include evidence from this study in revised guidance and educational materials for paramedics working with people who self-harm in the prehospital emergency setting.

Treatment with polyamine oxidase inhibitor reduces microglial activation and limits vascular injury in ischemic retinopathy

Retinal vascular injury is a major cause of vision impairment in ischemic retinopathies. Insults such as hyperoxia, oxidative stress and inflammation contribute to this pathology. Previously, we showed that hyperoxia-induced retinal neurodegeneration is associated with increased polyamine oxidation. Here, we are studying the involvement of polyamine oxidases in hyperoxia-induced injury and death of retinal vascular endothelial cells. New-born C57BL6/J mice were exposed to hyperoxia (70% O2) from postnatal day (P) 7 to 12 and were treated with the polyamine oxidase inhibitor MDL 72527 or vehicle starting at P6. Mice were sacrificed after different durations of hyperoxia and their retinas were analyzed to determine the effects on vascular injury, microglial cell activation, and inflammatory cytokine profiling. The results of this analysis showed that MDL 72527 treatment significantly reduced hyperoxia-induced retinal vascular injury and enhanced vascular sprouting as compared with the vehicle controls. These protective effects were correlated with significant decreases in microglial activation as well as levels of inflammatory cytokines and chemokines. In order to model the effects of polyamine oxidation in causing microglial activation in vitro, studies were performed using rat brain microvascular endothelial cells treated with conditioned-medium from rat retinal microglia stimulated with hydrogen peroxide. Conditioned-medium from activated microglial cultures induced cell stress signals and cell death in microvascular endothelial cells. These studies demonstrate the involvement of polyamine oxidases in hyperoxia-induced retinal vascular injury and retinal inflammation in ischemic retinopathy, through mechanisms involving cross-talk between endothelial cells and resident retinal microglia.

A repeating fast radio burst

Fast radio bursts are millisecond-duration astronomical radio pulses of unknown physical origin that appear to come from extragalactic distances. Previous follow-up observations have failed to find additional bursts at the same dispersion measure (that is, the integrated column density of free electrons between source and telescope) and sky position as the original detections. The apparent non-repeating nature of these bursts has led to the suggestion that they originate in cataclysmic events. Here we report observations of ten additional bursts from the direction of the fast radio burst FRB 121102. These bursts have dispersion measures and sky positions consistent with the original burst. This unambiguously identifies FRB 121102 as repeating and demonstrates that its source survives the energetic events that cause the bursts. Additionally, the bursts from FRB 121102 show a wide range of spectral shapes that appear to be predominantly intrinsic to the source and which vary on timescales of minutes or less. Although there may be multiple physical origins for the population of fast radio bursts, these repeat bursts with high dispersion measure and variable spectra specifically seen from the direction of FRB 121102 support an origin in a young, highly magnetized, extragalactic neutron star.

Identification and function probing of an antithrombin IIIβ conformation-specific antibody

ESSENTIALS: Antithrombin III (AT)β binds heparin with higher affinity than ATα. A conformation-specific antibody against ATβ, TPP2009, was made to investigate ATβ in hemostasis. TPP2009 bound specifically to heparin-ATβ and greatly reduced the anticoagulant effect of AT. This antibody was effective in elucidating the importance of ATβ in hemostasis.

BACKGROUND

Antithrombin III (AT)β is an isoform of AT that lacks the post-translational carbohydrate modification at Asn135. This isoform binds heparin with greater affinity than ATα, and has been shown to target antithrombotic function to the extracellular vascular endothelial injury site.

OBJECTIVES

To characterize a conformation-specific antibody against ATβ and begin to investigate the role of ATβ in maintaining hemostasis.

METHODS

Surface plasmon resonance (SPR), antigen binding and functional assays were conducted to characterize the mode of action of antibodies generated against heparin-bound ATβ (ATβ*H) by the use of phage display.

RESULTS

SPR and binding studies showed that one of the antibodies, TPP2009, bound specifically to ATβ*H and glycosaminoglycan-associated ATβ on endothelial cells. In diluted prothrombin and activated factor X (FXa)-induced clotting assays, TPP2009 dose-dependently reduced the anticoagulant effect of heparin in non-hemophilic and FVIII-deficient human plasma, with half-maximal effective concentrations (EC50 ) of 10.5 nm and 4.7 nm, respectively. In AT-deficient human plasma, TPP2009 dose-dependently inhibited the effects of exogenously added ATβ and heparin. In purified systems with ATβ and pentasaccharide, TPP2009 restored > 91% of FXa activity. TPP2009 dose-dependently reversed the effects of heparin in rabbit (EC50 , 25.7 nm) and cynomolgus monkey (EC50 , 21.5 nm) plasma, but not in mouse plasma. TPP2009 was also effective in partially restoring FXa activity in rabbit and cynomolgus monkey plasma treated with FVIII function-neutralizing antibodies.

CONCLUSIONS

TPP2009 specifically targets a unique conformational epitope on ATβ*H and blocks ATβ-mediated anticoagulation. It effectively promotes coagulation in plasma, indicating the importance of ATβ in hemostasis.

A CLEAR CASE OF MRSA SEPSIS, OF AN UNEXPECTED ORIGIN

A 56-year-old man with a history of uncontrolled type 2 diabetes mellitus, benign prostatic hypertrophy and history of recent knee and elbow abscess presented to the emergency department with nausea, vomiting, and fevers. Two days prior, he presented to the ER and was diagnosed with acute presumed prostatitis and urinary retention. He was discharged on ciprofloxacin and an indwelling Foley catheter with urology follow-up. After being unable to tolerate oral medications, he presented again to the emergency department, at which time, he was febrile and tachycardic. Physical exam was benign except for a boggy and tender prostate and bilateral CVA tenderness. Labs demonstrated leukocytosis, elevated HbA1C, and pyuria on urinalysis. Urine cultures collected at the patient's earlier emergency department visit demonstrated no growth. Computed tomography indicated an enlarged prostate with patchy areas of low density. He was admitted with sepsis secondary to prostatitis. Blood cultures on day one showed gram-positive cocci , methicillin resistant staph aureus (MRSA isolate) and persistent bacteremia for three days despite therapy with vancomycin. After adequate dosing of vancomycin, sterilization of the blood was achieved, yet urine culture demonstrated growth of MRSA. Transthoracic rchocardiogram (TTE) showed no signs of endocarditis with good visualization of valves. He was successfully treated with 14 days of vancomycin.

Heart failure: novel therapeutic approaches

Heart failure (HF) is a complex clinical syndrome that can result from any structural or functional cardiac disorders that impairs the ability of the ventricle to fill with or eject blood. Despite effective medical interventions, mortality and morbidity remain substantial. There have been significant advances in the therapy of HF in recent decades, such as the introduction of beta-blockers and antagonists of the renin-angiotensin system but still there is a major unmet need for better therapies for HF. In the present era, pathophysiology of HF has been explored. Various novel pathways, molecular sites have been identified, which contribute to the progression of the disease. By targeting these sites, newer pharmacological agents have been developed, which can play a promising role in the treatment of HF. This article focuses on recent advancements in pharmacotherapy of HF, which include agents targeting myocardial contractility, cytokines and inflammation, fibrosis and remodeling, myocardial metabolism, oxidative stress, and other newly defined pathways.

Large-scale discovery of novel genetic causes of developmental disorders

Despite three decades of successful, predominantly phenotype-driven discovery of the genetic causes of monogenic disorders, up to half of children with severe developmental disorders of probable genetic origin remain without a genetic diagnosis. Particularly challenging are those disorders rare enough to have eluded recognition as a discrete clinical entity, those with highly variable clinical manifestations, and those that are difficult to distinguish from other, very similar, disorders. Here we demonstrate the power of using an unbiased genotype-driven approach to identify subsets of patients with similar disorders. By studying 1,133 children with severe, undiagnosed developmental disorders, and their parents, using a combination of exome sequencing and array-based detection of chromosomal rearrangements, we discovered 12 novel genes associated with developmental disorders. These newly implicated genes increase by 10% (from 28% to 31%) the proportion of children that could be diagnosed. Clustering of missense mutations in six of these newly implicated genes suggests that normal development is being perturbed by an activating or dominant-negative mechanism. Our findings demonstrate the value of adopting a comprehensive strategy, both genome-wide and nationwide, to elucidate the underlying causes of rare genetic disorders.

The impact of early intra-articular administration of interleukin-1 receptor antagonist on lubricin metabolism and cartilage degeneration in an anterior cruciate ligament transection model

OBJECTIVE

Study the impact of intra-articular interleukin-1 receptor antagonist (IL-1 ra) treatment on lubricin biosynthesis following anterior cruciate ligament transection (ACLT) in the rat and evaluate the effect of combined IL-1 ra and recombinant human lubricin (rhPRG4) treatments on chondrocyte apoptosis.

METHODS

ACLT was performed in male Lewis rats. Treatments included IL-1 ra or vehicle (n = 36 in each group). IL-1 ra intra-articular dosing was performed on days 1, 3, 5 and 7 following ACLT using Anakinra (150 mg/ml; 40 μl). At 3 and 5 weeks, animals were sacrificed and RNA was isolated. Histological analyses included Safranin O and H&E. Lubricin synovial fluid (SF) lavage concentrations were determined at 5 weeks. ACLT animals were treated with a single injection of vehicle, IL-1 ra (75 mg/ml; 40 μl), rhPRG4 (200 μg/ml; 40 μl), or IL-1 ra + rhPRG4 (75 mg/ml + 200 μg/ml; 40 μl) (n = 6 in each group) on day 7 following ACLT and cartilage was probed for cleaved caspase-3 at 5 weeks.

RESULTS

IL-1 ra treatment improved lubricin expression (P < 0.001) and lubricin SF lavage concentrations in the IL-1 ra group was higher (P = 0.005) than the vehicle. IL-1 ra treatment reduced cartilage and synovial scores (P < 0.001) compared to vehicle. IL-1 ra and rhPRG4 acted synergistically to reduce caspase-3 positive chondrocytes (P < 0.001) compared to individual treatments.

CONCLUSION

IL-1 ra treatment preserved lubricin following ACLT and a combined treatment of IL-1 ra + rhPRG4 may act synergistically to reduce cartilage catabolism.

Diagnostic accuracy of integrated (18)F-FDG PET/CT for restaging patients with malignant germ cell tumours

OBJECTIVE

Evaluation of utility of fluorine-18 fludeoxyglucose ((18)F-FDG) positron emission tomography/CT (PET/CT) for restaging patients with primary malignant germ cell tumours (GCTs).

METHODS

Data of 92 patients (age, 31.94 ± 10.1 years; male/female, 86/6) with histopathologically confirmed malignant GCTs (gonadal, 88; mediastinal, 4; seminomatous, 47 and non-seminomatous, 45) who underwent (18)F-FDG PET/CT for restaging (suspected recurrence/post-therapy evaluation) were retrospectively analysed. Two experienced nuclear medicine physicians reviewed the PET/CT images in consensus, qualitatively and semi-quantitatively [maximum standardized uptake value (SUVmax)]. Histopathology (if available) and clinical/imaging/biochemical follow-up (minimum of 6 months) were employed as the reference standard.

RESULTS

(18)F-FDG PET/CT was interpreted as positive in 59 and negative in 33 patients. Local disease was seen in 5, nodal disease in 50 and distant metastasis in 22 patients. PET/CT was true positive in 49, false positive in 10, true negative in 30 and false negative in 3 patients. (18)F-FDG PET/CT showed sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 94.2%, 75.0%, 83.0%, 90.9% and 85.8% overall; 90.0%, 74.0%, 72.0%, 90.9% and 80.8% in seminomatous GCT; and 96.8%, 76.9%, 91.1%, 90.9% and 91.1% in non-seminomatous GCT, respectively. Difference in PET/CT accuracy for seminomatous and non-seminomatous GCTs was not significant (p = 0.263). PET/CT demonstrated disease in 13 patients with negative/equivocal conventional imaging findings and in 9 patients with normal tumour markers. No site- or histology-based difference was seen in SUVmax.

CONCLUSION

(18)F-FDG PET/CT demonstrates high diagnostic accuracy for restaging patients with malignant GCTs. It has comparable diagnostic performance in both seminomatous and non-seminomatous malignant GCTs.

ADVANCES IN KNOWLEDGE

The present article demonstrates high diagnostic accuracy of (18)F-FDG PET/CT for restaging both seminomatous and non-seminomatous malignant GCTs in a large patient population.

Ilaprazole: Is this a superior proton pump inhibitor for duodenal ulcer?

BACKGROUND

Preclinical studies have found ilaprazole to be significantly effective in preventing the development of reflux oesophagitis and gastric secretion in a dose-dependent manner; the drug also has a broad dose range and safety feature. Till date only one clinical study on patients with gastro-oesophageal reflux disease has shown its potency in suppressing gastric acid secretion.

OBJECTIVES

To review the published randomized controlled trials (RCTs) assessing the efficacy of ilaprazole in duodenal ulcer (DU) compared to other available proton pump inhibitors (PPI).

METHODS

RCTs comparing ilaprazole with other PPIs in DU were searched in the PubMed and Cochrane Library database using the term 'ilaprazole and duodenal ulcer'. All clinical studies showing effectiveness of ilaprazole in patients with DU, either full texts or scientific abstracts and found to be potentially eligible for the systematic review, were included and evaluated.

RESULTS

Four RCTs having follow-up data were included. A total of 1077 patients with DU were assessed. All the trials had included omeprazole as a comparator PPI. The majority of patients (80%) became asymptomatic after treatment in both the groups. None of the trials data predict ilaprazole to be superior to omeprazole in terms of efficacy in patients with DU.

CONCLUSION

The trials conducted were limited in numbers and all the trial data indicated the efficacy of ilaprazole to be similar to that of omeprazole. None of the trials indicated superiority of ilaprazole over the existing PPIs.

Glycoengineered factor IX variants with improved pharmacokinetics and subcutaneous efficacy

BACKGROUND

The rapid clearance of factor IX (FIX) necessitates frequent intravenous administration to achieve effective prophylaxis for patients with hemophilia B. Subcutaneous administration would be a preferred route of administration but is limited by bioavailability.

OBJECTIVES

To improve the pharmacokinetics (PK) and bioavailability of FIX, a screen was performed to identify positions for the introduction of novel glycosylation sites with maximal effect on PK and maintenance of coagulation activity.

METHODS

Two hundred fifty-one variants, each containing one additional N-linked glycosylation site, were screened in vitro, and the PK profiles of selected variants mapping to spatially distinct regions of FIX were evaluated in mice. Optimal variants were combined, and their PK and efficacy were determined in mice with hemophilia B.

RESULTS

Variants that mapped to spatially distinct regions of the FIX structure exhibited different degrees of improved PK and enabled selection of optimized sites while minimizing the loss of FIX activity. Combining the most effective N-glycan sites in the same FIX molecule resulted in further improvements in PK. An optimized variant containing three novel N-glycan sites (at amino acids 103, 151, and 228), and the activity enhancing 338A variant had double the specific activity of wild-type FIX, exhibited 4.5-fold reduced clearance and 2.4-fold increased subcutaneous bioavailability, and was efficacious at a fivefold lower mass dose than wild-type FIX after subcutaneous injection in a bleeding model in mice with hemophilia B.

CONCLUSIONS

Glycoengineering was used to significantly improve the subcutaneous PK and efficacy of FIX and may have advantages for subcutaneous dosing.

The impact of introducing thioguanine nucleotide monitoring into an inflammatory bowel disease clinic

BACKGROUND

Thioguanine nucleotides (TGNs) are the active product of thiopurine metabolism. Levels have been correlated with effective clinical response. Nonetheless, the value of TGN monitoring in clinical practice is debated. We report the influence of introducing TGN monitoring into a large adult inflammatory bowel disease (IBD) clinic.

PATIENTS AND METHODS

Patients with IBD undergoing TGN monitoring were identified from Purine Research Laboratory records. Whole blood TGNs and methylated mercaptopurine nucleotides were hydrolysed to the base and measured using HPLC. Clinical and laboratory data were obtained retrospectively.

RESULTS

One hundred and eighty-nine patients with 608 available TGN results were identified. In non-responders, TGNs directed treatment change in 39/53 patients. When treatment was changed as directed by TGN, 18/20 (90%) improved vs. 7/21 (33%) where the treatment decision was not TGN-directed, p < 0.001. Where treatment change was directed at optimisation of thiopurine therapy, 14/20 achieved steroid-free remission at 6 months vs. 3/10 where the TGN was ignored, (p = 0.037). Six per cent of patients were non-adherent, 25% under-dosed and 29% over-dosed by TGN. Twelve per cent of patients predominantly methylated thiopurines, this group had low TGN levels and high risk of hepatotoxicity. In responders, adherence and dosing issues were identified and TGN-guided dose-reduction was possible without precipitating relapse. Mean cell volume (MCV), white blood cell count (WBC) and lymphocyte counts were not adequate surrogate markers. MCV/WBC ratio correlated with clinical response, but was less useful than TGN for guiding clinical decisions.

CONCLUSIONS

Monitoring TGNs enables thiopurine therapy to be optimised and individualised, guiding effective treatment decisions and improving clinical outcomes.