Effect of meloxicam or robenacoxib administration timing on renal function and postoperative analgesia in cats undergoing ovariohysterectomy: A randomized, blinded, controlled clinical trial.

We evaluated the effect of administration timing of meloxicam and robenacoxib on renal function, platelet cyclo-oxygenase and perioperative analgesia in 60 cats undergoing ovariohysterectomy, in a prospective randomized blinded controlled study. Twelve cats were randomly allocated to one subcutaneous treatment group: meloxicam (0.2 mg/kg) or robenacoxib (2 mg/kg) at admission (MA, RA), at induction (MI, RI) and robenacoxib at the end of surgery (RE). All cats received the same anaesthesia protocol. Plasma renin activity (PRA), plasma creatinine, drug concentrations and serum thromboxane (TxB2) were measured sequentially. Anaesthesia significantly increased PRA, as activity at end of the surgery was higher than 2 h later (mean ± SD: 26.6 ± 2.8 versus 10.0 ± 3.9 ng/mL/h). PRA remained higher at 2 h post-surgery in admission groups compared to induction groups (p = .01). Serum TxB2 was lower with meloxicam than robenacoxib (p = .001), and was lower in the MA than each robenacoxib group at catheter placement. Admission groups (16/24 from RA and MA groups) received earlier rescue analgesia than other groups (p = .033). In conclusion, the renin-angiotensin system was activated during anaesthesia despite cyclo-oxygenase inhibition, possibly due to hypotension or surgical stimulation. There was no effect of drug or timing on the markers of renal function but one cat receiving meloxicam at induction had suspected IRIS grade II acute kidney injury.

Phase 1 study of the pan-HER inhibitor dacomitinib plus the MEK1/2 inhibitor PD-0325901 in patients with KRAS-mutation-positive colorectal, non-small-cell lung and pancreatic cancer.

BACKGROUND: Mutations in KRAS result in a constitutively activated MAPK pathway. In KRAS-mutant tumours existing treatment options, e.g. MEK inhibition, have limited efficacy due to resistance through feedback activation of epidermal growth factor receptors (HER). METHODS: In this Phase 1 study, the pan-HER inhibitor dacomitinib was combined with the MEK1/2 inhibitor PD-0325901 in patients with KRAS-mutant colorectal, pancreatic and non-small-cell lung cancer (NSCLC). Patients received escalating oral doses of once daily dacomitinib and twice daily PD-0325901 to determine the recommended Phase 2 dose (RP2D). (Clinicaltrials.gov: NCT02039336). RESULTS: Eight out of 41 evaluable patients (27 colorectal cancer, 11 NSCLC and 3 pancreatic cancer) among 8 dose levels experienced dose-limiting toxicities. The RP2D with continuous dacomitinib dosing was 15 mg of dacomitinib plus 6 mg of PD-0325901 (21 days on/7 days off), but major toxicity, including rash (85%), diarrhoea (88%) and nausea (63%), precluded long-term treatment. Therefore, other intermittent schedules were explored, which only slightly improved toxicity. Tumour regression was seen in eight patients with the longest treatment duration (median 102 days) in NSCLC. CONCLUSIONS: Although preliminary signs of antitumour activity in NSCLC were seen, we do not recommend further exploration of this combination in KRAS-mutant patients due to its negative safety profile.

Safety evaluation of the interchangeable use of robenacoxib in commercially-available tablets and solution for injection in cats.

BACKGROUND: Robenacoxib (Onsior™) is a non-steroidal anti-inflammatory drug developed for canine and feline use for the control of pain and inflammation. It is available as both tablets and solution for injection. The objective of this study was to evaluate the safety of the interchangeable use of commercially available robenacoxib formulations when administered to cats orally using 6 mg tablets and subcutaneously using a solution for injection containing 20 mg/mL. Thirty-four naïve healthy 4-month old cats were enrolled in this 37-day study and were randomized to four groups (three robenacoxib and one control). One robenacoxib group received the maximum recommended dose (MRD) rate of each formulation, while the other two received two and three times this dose rate. The cats underwent three 10-day treatment cycles comprised of seven days of once daily oral administration followed by three days of subcutaneous administration. The third cycle was followed by an additional seven days of oral treatment. The control group received oral empty gelatin capsules or subcutaneous saline injections. Assessment of safety was based on general health observations, clinical observations, physical, ophthalmic, electrocardiographic and neurological examinations, clinical pathology evaluations, food consumption, body weight, and macroscopic and microscopic examinations. Blood samples were collected for toxicokinetic evaluation. RESULTS: Blood concentrations of robenacoxib confirmed systemic exposure of all treated cats. All cats were in good health through study termination and there were no serious adverse events during the study. There were no changes in body weight, food consumption, ophthalmic, physical or neurological examinations during the study. Treatment-related abnormalities were of low occurrence at all doses and included injection site changes (transient edema with minimal or mild, subacute/chronic inflammation histologically) and prolongation of the QT interval. These findings were consistent with previously observed findings in studies with robenacoxib administered separately orally or subcutaneously in cats. Thus, there were no adverse effects that could be attributed specifically to the interchangeable use of oral and injectable robenacoxib. CONCLUSIONS: This 37-day laboratory study supports the safety of interchanging robenacoxib injection at a daily dose of 2 mg/kg with robenacoxib tablets at a daily dose of 1 mg/kg, or vice versa.

Six-month safety evaluation of robenacoxib tablets (Onsior™) in dogs after daily oral administrations.

BACKGROUND: Robenacoxib is a non-steroidal anti-inflammatory drug available for canine and feline use for the control of pain and inflammation marketed as Onsior™. The aim of this target animal safety study was to evaluate the 6-month safety profile of oral robenacoxib administration. It was a randomized, negative-controlled, parallel group study. Thirty-two healthy, young, experimentally naïve, purebred Beagle dogs were administered 0 (sham control, Group 1), 2, 6, and 10 mg/kg robenacoxib (corresponding to the upper end of the dosage range [1X, Group 2] and multiples thereof [3X and 5X, Group 3 and 4]), orally once daily for 6 months. Assessment of safety included general health and clinical observations, physical, neurological, ophthalmological and electrocardiographic examinations, gross and histopathological examinations and clinical pathology evaluations. Blood samples were collected for toxicokinetic assessment of robenacoxib. RESULTS: No serious adverse events were reported. When compared with control, no treatment effect was observed for body weight, feed or water consumption, clinical pathology, urinalysis and fecal examination parameters. There were no treatment-related changes in stifle joint tissues and microscopic/histopathology examinations of all tissues/organs were normal. Salivation and soft feces were noted in all groups but observed more frequently in the treated groups as compared with control. On Day 178, increased buccal mucosal bleeding times were observed in two treated animals (Group 3 and 4) and one dog in Group 4 displayed a retinal change. Decreased hopping and conscious proprioception was noted in four treated dogs. One dog in Group 2 had ventricular premature complexes. Post-mortem changes included mild, red foci on the cecum in one dog (Group 3) and minimal duodenal discoloration in one dog (Group 4), with no corresponding histological findings in either dog. Ovarian weights were decreased in females from Group 3 and 4 with no gross or histological changes in the ovaries. Blood concentrations of robenacoxib confirmed systemic exposure of treated dogs. Exposure increased with increasing doses and there were no accumulation of robenacoxib in blood. CONCLUSIONS: Robenacoxib was well tolerated at doses from 2 to 10 mg/kg/day and this 6-month study supports the safe use of Onsior™ (robenacoxib) tablets in dogs for the intended dosing regimen.

Combined BRAFV600E and MEK blockade for BRAFV600E-mutant gliomas.

BRAFV600E is a common finding in glioma (about 10-60% depending on histopathologic subclassification). BRAFV600E monotherapy shows modest preclinical efficacy against BRAFV600E gliomas and also induces adverse secondary skin malignancies. Here, we examine the molecular mechanism of intrinsic resistance to BRAFV600E inhibition in glioma. Furthermore, we investigate BRAFV600E/MEK combination therapy that overcomes intrinsic resistance to BRAFV600E inhibitor and also prevents BRAFV600E inhibitor induced secondary malignancies. Immunoblotting and Human Phospho-Receptor Tyrosine Kinase Array assays were used to interrogate MAPK pathway activation. The cellular effect of BRAFV600E and MEK inhibition was determined by WST-1 viability assay and cell cycle analysis. Flanked and orthotopic GBM mouse models were used to investigate the in vivo efficacy of BRAFV600E/MEK combination therapy and the effect on secondary malignancies. BRAFV600E inhibition leads to recovery of ERK phosphorylation. Combined BRAFV600E and MEK inhibition prevents reactivation of the MAPK signaling, which correlates with decreased cell viability and augmented cell cycle arrest. Similarly, mice bearing BRAFV600E glioma showed reduced tumor growth when treated with a combination of BRAFV600E and MEK inhibitor compared to BRAFV600E inhibition alone. Additional benefit of BRAFV600E/MEK inhibition was reflected by reduced cutaneous squamous-cell carcinoma (cSCC) growth (a surrogate for RAS-driven secondary maligancies). In glioma, recovery of MAPK signaling upon BRAF inhibition accounts for intrinsic resistance to BRAFV600E inhibitor. Combined BRAFV600E and MEK inhibition prevents rebound of MAPK activation, resulting in enhanced antitumor efficacy and also reduces the risk of secondary malignancy development.

Efficacy and safety of oral robenacoxib (tablet) for the treatment of pain associated with soft tissue surgery in client-owned dogs.

BACKGROUND: Non-steroidal anti-inflammatory drugs (NSAIDs) have been proven to be effective in controlling peri-operative pain in dogs. Robenacoxib is an NSAID with high selectivity for the cyclooxygenase (COX)-2 isoform. The objective of this study was to assess the efficacy and safety of an oral tablet formulation of robenacoxib in client-owned dogs undergoing soft tissue surgery. The study was a prospective, multi-center, randomized, masked, placebo-controlled, parallel-group clinical trial. A total of 239 dogs were included and randomly allocated in a 1:1 ratio to receive either robenacoxib or placebo. Each dog received an oral tablet administration of either robenacoxib, at a target dose of 2 mg/kg, or placebo once prior to surgery and for two additional days post-operatively. All dogs also received a pre-anesthetic dose of 0.2 mg/kg butorphanol (intravenous or intramuscular). Pain assessments were performed using the short form of the Glasgow Composite Measure Pain Scale. Robenacoxib was compared to the placebo group on a success/failure basis. Treatment failure was defined as the need for rescue therapy to control post-operative pain. RESULTS: Significantly (P = 0.019) more dogs administered robenacoxib were considered treatment successes (89 of 116, 76.72%) compared to dogs given placebo (74 of 115, 64.35%). The percentage of treatment failure was therefore 23.28% in the robenacoxib and 35.65% in the placebo group. The least squares mean total pain scores were significantly different between groups and in favor of robenacoxib at 3 and 5 hours (P < 0.05) and 8 hours post-extubation (P < 0.01). Pain at the surgery sites (response to touch) was also significantly improved at 3, 5 and 8 hours post-extubation in dogs receiving robenacoxib versus placebo (P < 0.01). In addition, a significant overall improvement in posture/activity was revealed with robenacoxib having lower scores versus placebo (P < 0.01). No significant differences between the robenacoxib and placebo groups in the frequency of reported adverse events were observed. CONCLUSIONS: Robenacoxib by oral (tablet) administration was effective and well tolerated in the control of peri-operative pain and inflammation associated with soft tissue surgery in dogs.

Safety evaluation of the interchangeable use of robenacoxib (Onsior™) tablets and solution for injection in dogs.

BACKGROUND: Robenacoxib (Onsior™) is a non-steroidal anti-inflammatory drug developed for canine and feline use for the control of pain and inflammation. It is available as both tablets and solution for injection. The objective of this safety study was to investigate the interchangeable use of two robenacoxib formulations in dogs using a novel study design alternating between oral tablets and subcutaneous injections. Thirty-two naïve healthy 4-month dogs were enrolled in this 88-day study and were randomized among four groups to be untreated or to receive robenacoxib at the highest recommended or elevated dose rates. The dogs were administered three 20-day treatment cycles each separated by a 14-day washout period. Each 20-day cycle was comprised of 10 days of once daily oral administration, 3 days of subcutaneous administration, followed by further 7 days of oral administration (Groups 2 to 4). The control group (Group 1) received oral empty gelatin capsules or subcutaneous saline injections. Assessment of safety was based on general health observations, clinical observations, physical and neurological examinations including ophthalmological examinations, electrocardiographic examinations and clinical pathology evaluations, food and water consumption, body weight, and macroscopic and microscopic examinations. Blood samples were collected for pharmacokinetic evaluation. RESULTS: Blood concentrations of robenacoxib confirmed systemic exposure of all treated dogs. All dogs were in good health through study termination and there were no serious adverse events during the course of the study. No changes in body weight, food consumption, ophthalmic, neurological examinations, electrocardiograms, buccal mucosal blood times, clinical pathology or organ weight were attributable to robenacoxib formulation administration. Primary treatment-related abnormalities were of low incidence at all doses. They were confined to macroscopic and microscopic changes observed locally at the subcutaneous injection sites and microscopic findings within the gastrointestinal tract. These findings were as expected based on previous studies with robenacoxib solution for injection alone and the known properties of this class of compound and mode of administration. There were no adverse effects which could be attributed specifically to the interchangeable use of oral and injectable robenacoxib. CONCLUSIONS: Alternating regimens of robenacoxib tablets and solution for injection were well tolerated in healthy young dogs.

Evaluation of cardiovascular effects of intravenous robenacoxib in dogs.

The objective of the study was to assess the cardiovascular effects of intravenous (IV) dosing with robenacoxib (Onsior® ) in conscious adult healthy beagle dogs. The study employed a randomized, open, placebo-controlled, four-phase Latin square design. A total of eight dogs received a single dose of 2 mg/kg and 4 mg/kg IV robenacoxib (test groups), 2 mg/kg subcutaneous (SC) robenacoxib (reference dose and route), and IV isotonic saline (control). There were no significant differences between groups for clinical observations, buccal mucosal bleeding time or blood hematology, coagulation, and clinical chemistry variables in all eight dogs. In a subset of four dogs, no significant differences between groups were detected using telemetric assessment for arterial blood pressure, heart rate, electrocardiogram, or body temperature over 8 hr postdose. In conclusion, no significant cardiovascular effects were detected after a single IV dose of 2 or 4 mg/kg robenacoxib in conscious healthy dogs.

Effect of benazepril and robenacoxib and their combination on glomerular filtration rate in dogs.

Combined use of angiotensin-converting enzyme inhibitors and nonsteroidal anti-inflammatory drugs may induce acute kidney injury, especially when combined with diuretics. The objective of this investigation was to evaluate the effect of benazepril, robenacoxib and their combination in healthy dogs. In each of two studies (studies 1 and 2), 32 beagle dogs were randomized into one of four groups in a parallel-group design. Groups received once-daily oral treatment for 7 days with placebo, benazepril, robenacoxib or benazepril plus robenacoxib. In study 2, all dogs received additionally 2 mg/kg furosemide orally twice daily. The primary endpoint was the glomerular filtration rate (GFR) estimated from the plasma clearance of iohexol. Secondary endpoints included standard clinical monitoring and, in study 2, plasma renin activity, urine volume, specific gravity and aldosterone concentration and water intake. Administration of furosemide induced diuresis, reduced GFR and activated the renin-aldosterone-angiotensin system. Benazepril and robenacoxib, administered alone or in combination, were tolerated well, did not decrease GFR with or without co-administration of furosemide and significantly reduced urinary aldosterone concentrations. No increased risk of acute kidney injury was identified with the combination of benazepril and robenacoxib in healthy dogs. Different effects might occur in dogs with heart or renal disease.

Mitogen-activated protein kinases (MAPKs) are modulated during Francisella tularensis infection, but inhibition of extracellular-signal-regulated kinases (ERKs) is of limited therapeutic benefit.

Francisella tularensis is a Gram-negative intracellular bacterium that causes the disease tularemia. The disease can be fatal if left untreated and there is currently no licenced vaccine available; the identification of new therapeutic targets is therefore required. Toll-like receptors represent an interesting target for therapeutic modulation due to their essential role in generating immune responses. In this study, we analysed the in vitro expression of the key mitogen-activated protein kinases (MAPKs) p38, JNK and ERK in murine alveolar macrophages during infection with F. tularensis. The phosphorylation profile of ERK highlighted its potential as a target for therapeutic modulation and subsequently the effect of ERK manipulation was measured in a lethal intranasal F. tularensis in vivo model of infection. The selective ERK1/2 inhibitor PD0325901 was administered orally to mice either pre- or post-challenge with F. tularensis strain LVS. Both treatment regimens selectively reduced ERK expression, but only the pre-exposure treatment produced decreased bacterial burden in the spleen and liver, which correlated with a significant reduction in the pro-inflammatory cytokines IFN-γ, MCP-1, IL-6, and TNF-α. However, no overall improvements in survival were observed for treated animals in this study. ERK may represent a useful therapeutic target where selective dampening of the immune response (to control the damaging pathology seen during infection) is combined with antibiotic treatment required to eradicate bacterial infection. This combination treatment strategy has been shown to be effective in other models of tularemia.

PKC/MEK inhibitors suppress oxaliplatin-induced neuropathy and potentiate the antitumor effects.

Oxaliplatin is a key drug commonly used in colorectal cancer treatment. Despite high clinical efficacy, its therapeutic application is limited by common, dose-limiting occurrence of neuropathy. As usual symptomatic neuropathy treatments fail to improve the patients' condition, there is an urgent need to advance our understanding of the pathogenesis of neuropathy to propose effective therapy and ensure adequate pain management. Oxaliplatin-induced neuropathy was recently reported to be associated with protein kinase C (PKC) activation. It is unclear, however, whether PKC inhibition can prevent neuropathy. In our current studies, we found that a PKC inhibitor, tamoxifen, inhibited oxaliplatin-induced neuropathy via the PKC/extracellular signal-regulated kinase (ERK)/c-Fos pathway in lumbar spinal cords (lumbar segments 4-6). Additionally, tamoxifen was shown to act in synergy with oxaliplatin to inhibit growth in tumor cells-implanted mice. Moreover, mitogen-activated protein kinase kinase (MEK) 1/2 inhibitor, PD0325901, suppressed oxaliplatin-induced neuropathy and enhanced oxaliplatin efficacy. Our results indicate that oxaliplatin-induced neuropathy is associated with PKC/ERK/c-Fos pathway in lumbar spinal cord. Additionally, we demonstrate that disruption of this pathway by PKC and MEK inhibitors suppresses oxaliplatin-induced neuropathy, thereby suggesting that PKC and MEK inhibitors may be therapeutically useful in preventing oxaliplatin-induced neuropathy and could aid in combination antitumor pharmacotherapy.

Effect of Cyclooxygenase(COX)-1 and COX-2 inhibition on furosemide-induced renal responses and isoform immunolocalization in the healthy cat kidney.

BACKGROUND: The role of cyclooxygenase(COX)-1 and COX-2 in the saluretic and renin-angiotensin responses to loop diuretics in the cat is unknown. We propose in vivo characterisation of isoform roles in a furosemide model by administering non-steroidal anti-inflammatory drugs (NSAIDs) with differing selectivity profiles: robenacoxib (COX-2 selective) and ketoprofen (COX-1 selective). RESULTS: In this four period crossover study, we compared the effect of four treatments: placebo, robenacoxib once or twice daily and ketoprofen once daily concomitantly with furosemide in seven healthy cats. For each period, urine and blood samples were collected at baseline and within 48 h of treatment starting. Plasma renin activity (PRA), plasma and urinary aldosterone concentrations, glomerular filtration rate (GFR) and 24 h urinary volumes, electrolytes and eicosanoids (PGE2, 6-keto-PGF1α, TxB2), renal injury biomarker excretions [N-acetyl-beta-D-glucosaminidase (NAG) and Gamma-Glutamyltransferase] were measured. Urine volume (24 h) and urinary sodium, chloride and calcium excretions increased from baseline with all treatments. Plasma creatinine increased with all treatments except placebo, whereas GFR was significantly decreased from baseline only with ketoprofen. PRA increased significantly with placebo and once daily robenacoxib and the increase was significantly higher with placebo compared to ketoprofen (10.5 ± 4.4 vs 4.9 ± 5.0 ng ml(-1) h(-1)). Urinary aldosterone excretion increased with all treatments but this increase was inhibited by 75 % with ketoprofen and 65 % with once daily robenacoxib compared to placebo. Urinary PGE2 excretion decreased with all treatments and excretion was significantly lower with ketoprofen compared to placebo. Urinary TxB2 excretion was significantly increased from baseline only with placebo. NAG increased from baseline with all treatments. Immunohistochemistry on post-mortem renal specimens, obtained from a different group of cats that died naturally of non-renal causes, suggested constitutive COX-1 and COX-2 co-localization in many renal structures including the macula densa (MD). CONCLUSIONS: These data suggest that both COX-1 and COX-2 could generate the signal from the MD to the renin secreting cells in cats exposed to furosemide. Co-localization of COX isoenzymes in MD cells supports the functional data reported here.

L-selectin shedding by NSAIDs: old friends in new dresses.

The recruitment of leukocytes to sites of inflammation requires the highly organized interplay of cell adhesion molecules on both leukocytes and inflamed endothelial cells, and disrupting the interaction of these molecules may compromise efficient recruitment of immune cells. Non-steroidal anti-inflammatory drugs inhibit inflammatory responses by several mechanisms including inhibition of prostaglandin synthesis and decreasing the expression of cell surface adhesion molecules. A report by Herrera-Garcia et al. [Eur. J. Immunol. 2013. 43: 55-64] in this issue of the European Journal of Immunology shows that the non-steroidal anti-inflammatory drug N-phenylanthranilic acid (N-Ph) causes L-selectin to be shed from the leukocyte plasma membrane and that this process in turn causes a decrease in leukocyte recruitment during inflammation in vivo. This finding may lead to novel approaches using N-Ph in the control of inflammatory processes as discussed in this Commentary.

In vivo modulation of the inflammatory response by nonsteroidal antiinflammatory drug-related compounds that trigger L-selectin shedding.

Diphenylamine-based nonsteroidal antiinflammatory drugs (NSAIDs) are able to cause in vitro the shedding of L-selectin. The aim of this work was to determine the physio-logic relevance of L-selectin shedding in the antiinflammatory effect exerted by NSAIDs in vivo. Chemical compounds structurally related to NSAIDs - including diphenyl-amine, N-phenylanthranilic acid (N-Ph), diphenylacetic acid - as well as the traditional NSAID indomethacin were studied using the zymosan air-pouch mouse model. Animals intramuscularly pretreated with indomethacin or N-Ph, but not with diphenyl-amine or diphenylacetic acid, showed a significant dose-dependent reduction in the number of neutrophils compared with untreated animals (N-Ph, IC50 = 6.7 mg/kg). Except for indomethacin, none of these compounds caused any significant reduction in cyclooxygenase-1 activity in vivo. In flow chamber experiments, N-Ph reduced the capability of human neutrophils to pass across the endothelial barrier by interfering with leukocyte rolling step on HUVEC. N-Ph, but not diphenylacetic acid, induced activation-independent L-selectin shedding in mouse neutrophils. Interestingly, N-Ph exerted an antiinflammatory effect similar to that of the anti-L-selectin blocking antibody Mel-14, although no additive action was observed when both compounds were combined. These data suggest that the L-selectin shedding induced by NSAIDs may be involved in the antiinflammatory action exerted by these compounds in clinical settings.

Robenacoxib versus meloxicam for the management of pain and inflammation associated with soft tissue surgery in dogs: a randomized, non-inferiority clinical trial.

BACKGROUND: Non-steroidal anti-inflammatory drugs (NSAIDs) are used routinely to control pain and inflammation after surgery in dogs. Robenacoxib is a new NSAID with high selectivity for the cyclo-oxygenase (COX)-2 isoform of COX. The objective of this study was to evaluate the efficacy and tolerability of robenacoxib for the management of peri-operative pain and inflammation associated with soft tissue surgery in dogs. The study was a prospective, randomized, blinded, positive-controlled, non-inferiority, multi-center clinical trial. A total of 174 dogs undergoing major soft tissue surgery were included and randomly allocated in a 2:1 ratio to receive either robenacoxib (n = 118) or the positive control, meloxicam (n = 56). Each dog received an initial dose subcutaneously prior to surgery (robenacoxib 2 mg/kg, meloxicam 0.2 mg/kg), followed by daily oral doses (robenacoxib 1-2 mg/kg, meloxicam 0.1 mg/kg) for 12 days (range 10-14) after surgery. Pain and inflammation were assessed subjectively using the Glasgow Composite Pain Scale (GCPS) by clinicians as the primary end point and additional evaluations by the clinicians and animal owners as secondary endpoints. RESULTS: Both treatments provided similar pain control, with no significant differences between groups for any efficacy variable using non-parametric analyses (Mann-Whitney U test). In no dog was analgesic rescue therapy administered. Non-inferior efficacy of robenacoxib compared to meloxicam was demonstrated statistically for the primary and all secondary endpoints using parametric analysis of variance, although the data were not normally distributed even after log transformation. For the primary endpoint (reciprocal of the modified GCPS score), the relative efficacy of robenacoxib/meloxicam was 1.12 with a 95% confidence interval of 0.97-1.29. CONCLUSION: A treatment regimen of robenacoxib by subcutaneous injection followed by oral tablets had good tolerability and non-inferior efficacy compared to meloxicam for the management of peri-operative pain and inflammation associated with soft tissue surgery in dogs.

Cancer therapy monitoring in xenografts by quantitative analysis of circulating tumor DNA.

CONTEXT: Circulating tumor DNA (ctDNA) is a promising biomarker in cancer. MATERIALS AND METHODS: We generated xenograft models of cancer and detected ctDNA in plasma by qRCR targeting human AluJ sequences. RESULTS: Our assay reached single cell sensitivity in vitro and a correlation between ctDNA amount and tumor size was observed in vivo. Treatment with a mitogen activated protein kinase kinase (MEK)-inhibitor (BAY 869766) reduced ctDNA levels. Using this assay, we also confirmed that high levels of cell-free DNA are found in cancer patients compared to healthy individuals. DISCUSSION AND CONCLUSION: We show that ctDNA may be useful biomarker for monitoring tumor growth and treatment response.

Safety of oral robenacoxib in the cat.

The safety of robenacoxib, a nonsteroidal anti-inflammatory drug with high selectivity for inhibition of the cyclooxygenase (COX)-2 isoform of COX, was investigated in the cat in two randomized, blinded, placebo-controlled, parallel-group studies. Robenacoxib was administered orally to healthy young domestic short-hair cats at dosages of 0 (placebo), 5 and 10 mg/kg once daily for 28 days (study 1) and at 0 (placebo), 2, 6 and 10 mg/kg twice daily for 42 days (study 2). The recommended minimum dosage for robenacoxib tablets in cats is 1 mg/kg once daily (range 1-2.4 mg/kg). Relative to placebo treatment, no toxicologically significant effects of robenacoxib were recorded in either study, based on general observations of health, haematological and clinical chemistry variables and urinalyses in life, and by post mortem organ weight, gross pathology and histopathology assessments. Pharmacokinetic-pharmacodynamic simulations indicated that all dosages of robenacoxib were associated with marked inhibition of COX-2 at peak effect (median I(max) 97.8-99.4% inhibition) with lesser inhibition of COX-1 (median I(max) 26.8-58.3% inhibition). Inhibition of the COXs was short lasting, with >10% median inhibition persisting for 4.0 h for COX-2 and 1.5 h for COX-1. These levels of inhibition of COX-1 and COX-2 twice daily with robenacoxib were not associated with any detectable toxicity, suggesting that, as previously described in dogs, the high safety index of robenacoxib in cats may be related to a combination of its high COX-2 selectivity and short residence time in the central compartment.

Serum C-reactive protein and iron levels following gonadectomy are not modified by perioperative administration of robenacoxib to dogs.

The aim of this study was to evaluate the perioperative effects of robenacoxib on serum C-reactive protein (CRP) and iron concentrations in dogs undergoing gonadectomy. In a prospective, blinded, controlled clinical trial, 60 healthy dogs were randomly assigned to receive preoperative subcutaneous injection of either robenacoxib [2 mg/kg body weight (BW)], meloxicam (0.2 mg/kg BW), or saline (0.04 mL/kg BW), followed by oral administration over 72 h (robenacoxib: 2 to 4 mg/kg BW; meloxicam: 0.1 mg/kg BW; saline: gelatin capsules). Blood samples were taken before surgery and 12, 24, 48, 72 h, and 7 d after surgery. Pain scores were assessed via the short-form Glasgow Composite Pain Scale over 72 h postoperatively. C-reactive protein (CRP) and iron serum levels increased and decreased (P < 0.01, both), respectively, after surgery and returned to baseline within 1 wk. No differences were observed among treatments (P > 0.05) or based on surgery/gender (P > 0.05). Pain assessment revealed a higher incidence of treatment failure in saline (6 females versus 2 and 1 female in robenacoxib and meloxicam, respectively). In conclusion, robenacoxib and meloxicam had no influence on postoperative CRP or iron in dogs, which suggests that these nonsteroidal anti-inflammatory drugs (NSAIDs) do not have a relevant effect on these biomarkers.

Le but de cette étude était d'évaluer les effets périopératoires du robenacoxib sur les concentrations sériques de protéine C réactive (CRP) et de fer chez des chiens subissant une gonadectomie. Dans un essai clinique prospectif, en aveugle et contrôlé, 60 chiens en bonne santé ont été randomisés pour recevoir une injection sous-cutanée préopératoire de robenacoxib [2 mg/kg de poids corporel (PC)], de méloxicam (0,2 mg/kg de poids corporel) ou de solution saline (0,04 mL/kg de poids corporel), suivie d'une administration orale pendant 72 h (robenacoxib : 2 à 4 mg/kg de poids corporel; méloxicam : 0,1 mg/kg de poids corporel; saline : gélules). Des échantillons de sang ont été prélevés avant la chirurgie et 12, 24, 48, 72 h et 7 jours après la chirurgie. Les pointages de douleur ont été évalués via l'échelle abrégée Glasgow Composite Pain Scale sur 72 h après l'opération. Les taux sériques de CRP et de fer ont augmenté et diminué (P < 0,01, les deux), respectivement, après la chirurgie et sont revenus à la valeur de base en 1 semaine. Aucune différence n'a été observée entre les traitements (P > 0,05) ou en fonction de la chirurgie/du sexe (P > 0,05). L'évaluation de la douleur a révélé une incidence plus élevée d'échec du traitement avec la saline (6 femelles contre 2 et 1 femelles pour le robenacoxib et le méloxicam, respectivement). En conclusion, le robenacoxib et le méloxicam n'ont eu aucune influence sur la CRP ou le fer postopératoire chez le chien, ce qui suggère que ces anti-inflammatoires non stéroïdiens (AINS) n'ont pas d'effet pertinent sur ces biomarqueurs.(Traduit par Docteur Serge Messier).

Cationic liposomal co-delivery of small interfering RNA and a MEK inhibitor for enhanced anticancer efficacy.

PURPOSE: To test whether co-delivery of anticancer small interfering RNA (siRNA) and a chemical MEK inhibitor using cationic liposomes enhances anticancer activity in vitro and in vivo. METHOD: MEK inhibitor PD0325901 was encapsulated in lipid layers of N',N''-dioleylglutamide-based cationic liposomes (DGL). Mcl1-specific siRNA (siMcl1) was complexed to DGL or PD0325901-loaded liposomes (PDGL). Efficiency of cellular siRNA delivery was tested using fluorescent double-stranded RNA. Silencing of target proteins was evaluated using Western blotting and real-time quantitative polymerase chain reactions. In vivo anticancer activity was tested using xenografted mice. RESULTS: Size and zeta potential of PDGL were similar to DGL. PDGL could deliver double-stranded RNA into cells with efficiencies comparable to DGL. Cellular co-delivery of siMcl1 and PD0325901 reduced expression of Mcl1 and pERK1/2 proteins and more effectively reduced tumor cell survival than other treatments. In mice, siMcl1 and PD0325901 co-delivered by PDGL inhibited growth of tumors 79%. Substantial apoptosis of tumor cells was observed following PDGL-mediated co-delivery of siMcl1, but not in other groups. CONCLUSIONS: PDGL-mediated co-delivery of siMcl1 and MEK inhibitor, PD0325901, could serve as a potential strategy for combination chemogene anticancer therapy.

Evaluation of subcutaneous and oral administration of robenacoxib and meloxicam for the treatment of acute pain and inflammation associated with orthopedic surgery in dogs.

OBJECTIVE: To assess efficacy and tolerability of robenacoxib for control of pain and inflammation in dogs undergoing orthopedic surgery. ANIMALS: 140 client-owned dogs. PROCEDURES: A multicenter, prospective, randomized, blinded field trial was conducted to compare robenacoxib (97 dogs) and meloxicam (43 dogs). After randomization, each dog received an initial dose (robenacoxib, 2 mg/kg; meloxicam, 0.2 mg/kg) via SC injection before surgery and daily doses (robenacoxib, 1 to 2 mg/kg; meloxicam, 0.1 mg/kg) administered orally for up to 15 days after surgery. Efficacy was assessed by veterinarians and owners via numeric rating scales and visual analogue scales. Safety was assessed on the basis of reported adverse events, clinical signs, results of hematologic and biochemical analyses, and buccal mucosa bleeding times. RESULTS: Treatment groups were balanced with respect to baseline and demographic data. Both treatments provided similar adequate pain control, as assessed with a modified Glasgow pain scale as the primary end point and supported by secondary end points in evaluations conducted by veterinarians and owners. For the primary end point, the ratio of the reciprocal of the scores for robenacoxib to meloxicam was 1.16 (95% confidence interval, 0.98 to 1.37). No dogs required rescue analgesia. Both treatments were associated with only minor adverse events, which were not necessarily related to the administered treatments and did not affect mucosal bleeding times. CONCLUSIONS AND CLINICAL RELEVANCE: Robenacoxib provided efficacy and tolerability similar to those of meloxicam for the management of perioperative pain and inflammation in dogs undergoing orthopedic surgery.