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This article describes the mechanism of action, pharmacokinetics, and pharmacodynamics of aspirin at doses used for cardiovascular prevention and provides specific management recommendations for optimal use in clinical practice. The paper highlights practical aspects related to antiplatelet therapy, including the optimal dose of aspirin, concomitant treatment with other NSAIDs, and strategies for the prevention of gastrointestinal toxicity. Specifically, we revise the benefits and hazards in different clinical settings to help the clinician in the decision-making process for individuals who have different risks for cardiovascular and gastrointestinal bleeding events. [ABSTRACT FROM AUTHOR]

Tumour biomarker status is being used more and more frequently to guide treatment decisions in patients with metastatic colorectal cancer (mCRC). Continued cycles of hypothesis generation and biomarker testing in retrospective, prospective-retrospective and prospective analyses from studies of the epidermal growth factor (EGFR)-targeted monoclonal antibodies (mAbs), panitumumab and cetuximab, have resulted in improved patient selection in mCRC. Initial data suggested EGFR-targeted mAb treatment should be limited to patients with KRAS exon 2 wild-type (WT) tumours, but the availability of tumour samples from large phase III studies permitted evaluation of additional potential biomarkers of activity for these agents. Subsequent analyses further refined the target population to those patients whose tumours were WT for KRAS and NRAS exons 2, 3 and 4 (i.e., those with RAS WT status). Here, we review key clinical data for panitumumab in mCRC across the lines of treatment, assessing in detail the impact of more comprehensive RAS selection on patient outcomes. Panitumumab data across first- to third-line therapy consistently demonstrate that by testing tumour RAS status, it is possible to select patients more likely to benefit from treatment. [ABSTRACT FROM AUTHOR]

The development of small-molecule inhibitors of inflammatory cascade signaling kinases offers a potential approach to treating rheumatoid arthritis (RA). Spleen tyrosine kinase is one such tyrosine kinase. Recent research efforts have focussed on the development and testing of a spleen tyrosine kinase inhibitor, fostamatinib. We reviewed the results of the clinical trials of fostamatinib in RA with the aim of outlining its clinical efficacy and the nature and frequency of its main adverse events. To date, this drug has been evaluated in over 3,200 RA patients enrolled in three phase II, one phase IIb and three phase III trials. These studies showed fostamatinib was effective. In four trials in which patients received 100 mg twice daily, fostamatinib reduced inflammatory synovitis; the relative risks of achieving American College of Rheumatology Responder rates compared with placebo in the combined studies ranged from 1.6 for 20 % of responders to 3.7 for 70 % of responders. There was a similar relative risk of achieving a clinically meaningful reduction in disability of 1.6 for the chance of patients achieving a reduction in health assessment questionnaire scores of 0.22 or more. Three of the trials examined the impact of fostamatinib on erosive radiographic damage using changes in the modified total Sharp score. None of them provided any evidence for a significant effect of fostamatinib on erosive damage over 6 months. All the trials included descriptions of adverse events. Hypertension was common, involving over 40 % of patients treated. Other common adverse events included diarrhoea, neutropenia and increases in hepatic enzyme levels. Some patients developed infections. On the conclusion of the phase III trials, one of the main pharmaceutical sponsors decided not to further develop fostamatinib for RA. [ABSTRACT FROM AUTHOR]

Preoperative infusional 5-fluorouracil (5-FU) and concurrent radiation therapy (RT) followed by total mesorectal surgery is the current standard of care for locally advanced rectal cancer (LAR). When compared with postoperative 5-FU-based chemoradiation, this strategy is associated with significantly lower rates of local relapse, lower toxicity and better compliance. Capecitabine is a rationally designed oral prodrug that is converted into 5-FU by intracellular thymidine phosphorylase. Substitution of infusional 5-FU with capecitabine is an attractive option that provides a more convenient administration schedule and, possibly, increased efficacy. Indeed, incorporation of capecitabine in combined modality neoadjuvant therapy for LAR has been under intense investigation during the last 10 years. Phase I and II clinical trials showed that a regimen consisting of capecitabine 825 mg/m2 twice daily for 7 days/week continuous oral administration in combination with RT is an active and well tolerated regimen, thereby being the preferred concurrent regimen. The definitive demonstration that efficacy of capecitabine/RT is similar to 5-FU/RT has been provided by the NSABP-R-04 and the German Margit trials. One approach to improve outcomes in rectal cancer is to deliver a second RT- sensitizing drug with effective systemic activity. Oxaliplatin and irinotecan are therefore good candidates. However, two phase HI trials demonstrated that incorporation of oxaliplatin to capecitabine with RT did not improve early outcomes and, by contrast, increased toxicity. Capecitabine has also been combined with irinotecan. This regimen showed encouraging results in phase I and II clinical trials, which led to an ongoing phase III clinical trial. New strategies with induction chemotherapy with or without chemo- radiation prior to surgery are currently under investigation. Whether or not capecitabine has a role in this setting is being investigated in ongoing trials. Incorporation of agents directed towards new targets, such as anti-epidermal growth factor receptor (EGFR) antibodies or antiangiogenic agents, in combination preoperative regimens, is being hampered by results of early trials in which efficacy outcomes with cetuximab were poor and an excessive rate of surgical complications with bevacizumab was observed. The lack of improvements in efficacy with the addition of cetuximab or bevacizumab in the adjuvant treatment of colon cancer led to concerns about further development of these agents in rectal cancer. The role of capecitabine in the postoperative adjuvant setting is the aim of the ongoing Dutch SCRIPT trial. The prediction of response associated with capecitabine has been based on expression of thymidylate synthase and dihydropyrimidine dehydrogenase, as well as on gene expression arrays. All these procedures require further validation and should be considered as investigational. In conclusion, capecitabine can safely and effectively replace intravenous continuous infusion of 5-FU in the preoperative chemoradiation setting for rectal cancer management. The addition of other new antineoplastic agents to a fluoropy- rimidine-based regimen remains investigational. [ABSTRACT FROM AUTHOR]

Tacrolimus is a cornerstone immunosuppressant agent in the prevention of organ rejection following transplantation. While typically administered twice daily (Prograf®), a modified-release once-daily formulation (Advagraf®) has recently been developed and licensed for use. To date, the majority of published data relating to the use of Advagraf® have arisen from industry- sponsored clinical trials. These have shown that conversion from Prograf* to Advagraf® on a 1 mg : 1 mg basis in both stable and de novo kidney and liver transplant recipients yields lower peak concentrations (Cmax) but equivalent overall drug exposure (area under the concentration-time curve from 0 to 24 hours post-dose; AUC24) and trough concentrations (Cmin). This has led to the proposal that the same total daily dose, target Cmin and therapeutic drug monitoring (TDM) strategies can be applied irrespective of preparation. However, while Advagraf® fulfils criteria for bioequivalence according to the European Medicines Agency and US FDA, lower tacrolimus exposure has been observed in the majority of clinical studies, particularly in the early post- transplant period. This has resulted in a need for higher doses of Advagraf® compared with Prograf® to achieve similar Cmin values. Significant between- subject variability in the Cmin/AUC24 relationship with Advagraf® has also been demonstrated, suggesting possible problems with TDM based on Cmin values. In non-comparative conversion studies, Advagraf® demonstrated similar efficacy and safety to Prograf®. However, phase III studies in de novo kidney and liver transplant recipients have shown higher rates of acute rejection with Advagraf®, possibly explained by the differing Cmax values achieved with the two preparations. While it has been suggested that once- daily administration may improve compliance, no studies have proven this to be the case. This article reviews the pharmacokinetics, efficacy, adverse effects and utility of Advagraf® in relation to its equivalence to Prograf®, and areas that require additional research are identified. [ABSTRACT FROM AUTHOR]