The threshold rate of oral atypical anti-psychotic adherence at which paliperidone palmitate is cost saving

OBJECTIVE

To identify, estimate, and compare 'real world' costs and outcomes associated with paliperidone palmitate compared with branded oral atypical anti-psychotics, and to estimate the threshold rate of oral atypical adherence at which paliperidone palmitate is cost saving.

METHODS

Decision analytic modeling techniques developed by Glazer and Ereshefsky have previously been used to estimate the cost-effectiveness of depot haloperidol, LAI risperidone, and, more recently, LAI olanzapine. This study used those same techniques, along with updated comparative published clinical data, to evaluate paliperidone palmitate. Adherence rates were based on strict Medication Event Monitoring System (MEMS) criteria. The evaluation was conducted from the perspective of US healthcare payers.

RESULTS

Paliperidone palmitate patients had fewer mean annual days of relapse (8.7 days; 6.0 requiring hospitalization, 2.7 not requiring hospitalization vs 17.8 days; 12.4 requiring hospitalization, 5.4 not requiring hospitalization), and lower annual total cost ($20,995) compared to oral atypicals (mean $22,481). Because paliperidone palmitate was both more effective and less costly, it is considered economically dominant. Paliperidone palmitate saved costs when the rate of adherence of oral atypical anti-psychotics was below 44.9% using strict MEMS criteria. Sensitivity analyses showed results were robust to changes in parameter values. For patients receiving 156 mg paliperidone palmitate, the annual incremental cost was $1216 per patient (ICER = $191 per day of relapse averted). Inclusion of generic risperidone (market share 18.6%) also resulted in net incremental cost for paliperidone palmitate ($120; ICER = $13). Limitations of this evaluation include use of simplifying assumptions, data from multiple sources, and generalizability of results.

CONCLUSIONS

Although uptake of LAIs in the US has not been as rapid as elsewhere, many thought leaders emphasize their importance in optimizing outcomes in patients with adherence problems. The findings of this analysis support the cost-effectiveness of paliperidone palmitate in these patients.

Reduction of endoplasmic reticulum stress using chemical chaperones or Grp78 overexpression does not protect muscle cells from palmitate-induced insulin resistance

Endoplasmic reticulum (ER) stress is proposed as a novel link between elevated fatty acids levels, obesity and insulin resistance in liver and adipose tissue. However, it is unknown whether ER stress also contributes to lipid-induced insulin resistance in skeletal muscle, the major tissue responsible of insulin-stimulated glucose disposal. Here, we investigated the possible role of ER stress in palmitate-induced alterations of insulin action, both in vivo, in gastrocnemius of high-palm diet fed mice, and in vitro, in palmitate-treated C(2)C(12) myotubes. We demonstrated that 8 weeks of high-palm diet increased the expression of ER stress markers in muscle of mice, whereas ex-vivo insulin-stimulated PKB phosphorylation was not altered in this tissue. In addition, exposure of C(2)C(12) myotubes to either tuncamycine or palmitate induced ER stress and altered insulin-stimulated PKB phosphorylation. However, alleviation of ER stress by either TUDCA or 4-PBA treatments, or by overexpressing Grp78, did not restore palmitate-induced reduction of insulin-stimulated PKB phosphorylation in C(2)C(12) myotubes. This work highlights that, even ER stress is associated with palmitate-induced alterations of insulin signaling, ER stress is likely not the major culprit of this effect in myotubes, suggesting that the previously proposed link between ER stress and insulin resistance is less important in skeletal muscle than in adipose tissue and liver.

A 52-week open-label study of the safety and tolerability of paliperidone palmitate in patients with schizophrenia

The safety and tolerability of paliperidone palmitate, an injectable atypical antipsychotic agent, were assessed in a 1-year open-label extension of a double-blind study in patients with schizophrenia. Patients from the double-blind study who experienced a recurrence, remained recurrence free until study end, or who were in the transition, maintenance or double-blind phases and had received at least one injection of paliperidone palmitate when enrollment was stopped, were eligible for the open-label extension. Patients received gluteal injections of paliperidone palmitate once every 4 weeks: starting dose 50 mg eq. followed by 25, 50, 75, or 100 mg eq. flexible dosing. Of the 388 patients enrolled, 288 completed the open-label extension. During the open-label extension, the median (range) duration of exposure to paliperidone palmitate was 338 days (10; 390), and 74% of patients received all 12 open-label injections of paliperidone palmitate. The most frequent (≥ 5% in total group) adverse events were insomnia (7%); worsening of schizophrenia; nasopharyngitis; headache; and weight increase (6% each). Potentially prolactin-related adverse events occurred in 13 (3%) patients, mostly women, and none resulted in study discontinuation. Extrapyramidal treatment-emergent adverse events were reported in 25 (6%) patients; tremor was the most frequently reported (n = 8, 2%). At open-label extension endpoint, investigator-rated redness at the injection site was observed in ≤ 4% of patients in each group. Injection-site pain was rated by investigators as absent in 82-87% of patients. Schizophrenia symptoms measured by Positive and Negative Syndrome Scale and personal and social performance changes improved during the open-label extension.

Hypermethylation of hepatic glucokinase and L-type pyruvate kinase promoters in high-fat diet-induced obese rats

Obesity-dependent insulin resistance and type 2 diabetes mellitus are closely associated with decreased glucose utilization and down-regulation of hepatic glycolytic enzymes expression. Previously, we showed that DNA hypermethylation is involved in age-dependent susceptibility to hepatic insulin resistance and diabetes. However, what we cannot distinguish is whether the age-related obesity contributes to DNA hypermethylation in those natural aging rats. In the present study, we hypothesize that DNA methylation plays a crucial role in the regulation of glycolytic enzymes in the high-fat diet-induced obesity. Here, we report that DNA hypermethylation is correlated with a decline in hepatic glucokinase (Gck) and L-type pyruvate kinase (LPK) expression in high-fat diet-induced obese rats as compared with the control diet group. Down-regulation of Gck and LPK expression are reversed by the 5-aza-2'-deoxycytidine in the cell model of steatosis. These novel observations indicate that DNA methylation is involved in the development of metabolic diseases, such as obesity, insulin resistance, type 2 diabetes mellitus, and nonalcoholic steatohepatitis, suggesting that the hypermethylation level of Gck and LPK promoters may be a useful parameter for the evaluation of obesity-induced insulin resistance and fatty liver.

miR-375 enhances palmitate-induced lipoapoptosis in insulin-secreting NIT-1 cells by repressing myotrophin (V1) protein expression

Lipoapoptosis of pancreatic beta cells caused by elevated circulating free fatty acids (FFAs) has now been recognized to be a pivotal factor contributing to beta cellular dysfunction and beta-mass lose in type 2 diabetes. Although recent studies suggested an important role for the ceramide pathway in the late destructive phase of lipid overload in the pancreatic beta cells, the overall underlying mechanisms leading to lipoapoptosis, however, remained poorly understood. mir-375 was recently characterized to be a pancreatic islet-specific miRNA implicated in the regulation of insulin secretion and beta-mass turnover. In the present study we further examined its effect on palmitate-induced lipoapoptosis in NIT-1 cells, a NOD-derived beta-cell line. It was found that NIT-1 cells with ectopic mir-375 expression were much more susceptible to palmitate-induced lipoapoptosis. In contrast, knockdown of endogenous pri-mir-375 expression by a modified antisense oligo, 2'-O-me-375, almost completely protected NIT-1 cells from palmitate-induced lipoapoptosis. We further demonstrated that mir-375 could target V1 mRNA and repress its translation. Consistent with this assumption, NIT-1 cells transfected with 2'-O-me-375 showed significant higher levels of V1 protein after palmitate induction. Together, our data suggest that mir-375 could be a potential therapeutic target for prevention and intervention of beta-cell dysfunction and beta-mass lose in type 2 diabetes.

Paliperidone palmitate - review of the efficacy, safety and cost of a new second-generation depot antipsychotic medication

OBJECTIVE

To describe the efficacy, safety and cost of paliperidone palmitate, a depot antipsychotic medication recently approved for the treatment of schizophrenia.

DATA SOURCES

A literature search was conducted by querying the websites http://www.pubmed.gov, http://www.fda.gov, http://www.accessdata.fda.gov/scripts/cder/drugsatfda and http://www.clinicaltrials.gov for the search term 'paliperidone palmitate'. Cost information was obtained from the pharmaceutical vendor servicing a local state-operated psychiatric facility.

STUDY SELECTION

All available reports of studies were identified. Product labelling provided additional information.

DATA EXTRACTION

Descriptions of the principal results and calculation of the number needed to treat (NNT) and number needed to harm (NNH) for relevant dichotomous outcomes were extracted from the study reports and synopses. Additional safety outcomes subject to NNH analysis were obtained from product labelling.

DATA SYNTHESIS

Paliperidone palmitate is a newly available depot formulation of paliperidone (the 9-OH metabolite of risperidone). Upon injection into the deltoid or gluteal muscle, the release of the drug starts as early as day 1, reaches maximum plasma concentrations at 13 days and lasts for as long as 126 days. Maximum concentration following deltoid injection is approximately 28% higher compared with injection into the gluteal muscle, and thus paliperidone palmitate requires initiation by two initial deltoid injections spread 1 week apart to achieve therapeutic concentrations rapidly. Subsequent injections are at 4-week intervals. Acute efficacy was evidenced by four short-term double-blind, randomised, placebo-controlled, fixed-dose studies of acutely relapsed adult inpatients who met DSM-IV criteria for schizophrenia. NNT for a 30% or greater decrease in the Positive and Negative Syndrome Scale total score compared with placebo was consistently lower for the higher dose strengths of 156 and 234 mg, suggesting a therapeutic dose-response. Treatment with paliperidone palmitate at doses between 39 and 156 mg significantly delayed the time to recurrence of symptoms of schizophrenia after 24 weeks of maintained symptom stability. The NNT vs. placebo to avoid a recurrence of symptoms was 5 (95% CI 4-7). Overall, paliperidone palmitate was reasonably well tolerated, with low rates of extrapyramidal symptoms or body weight gain; however, these may be more common at higher doses. Injection site reactions occurred at a rate ranging from 4% to 10%, depending on the dose regimen, compared with 2% for the pooled placebo arms. The acquisition cost of a maintenance dose of paliperidone palmitate calculated on a per day basis is similar to that for risperidone microspheres, but about double the cost for oral paliperidone and approximately 19 times the cost of oral generic risperidone.

CONCLUSIONS

Paliperidone palmitate is efficacious for the acute and maintenance treatment of schizophrenia and is reasonably well tolerated. It offers several advantages over other available second-generation depot antipsychotics: it comes in prefilled syringes in a number of different dosage strengths; it does not require refrigeration; it does not require supplementation with oral antipsychotics; it can be administered once monthly; it can be administered with a very small bore needle; the injection volume is small; the injection site can be either the deltoid or gluteal muscles; it does not require an additional precautionary observation period after the injection. For patients for whom oral risperidone or paliperidone is otherwise effective, paliperidone palmitate offers a guaranteed delivery system that enhances adherence. However, the high acquisition cost of paliperidone palmitate will likely be an important obstacle to its routine use.

Bone wax can cause foreign body granuloma in the medulla oblongata

Bone wax is commonly used in neurosurgical practice as a haemostatic and sealing agent. It is a safe agent, but may lead to adverse effects such as infection, epistaxsis, allergic reaction or foreign body granuloma. There are very few reported cases of the neurological complications of remnant bone wax in the subdural or subarachnoid space. The authors report the case of a foreign body granuloma infiltration through the medulla oblongata due to remnant bone wax in the subarachnoid space after posterior fossa decompressive surgery.

Pioglitazone attenuates fatty acid-induced oxidative stress and apoptosis in pancreatic beta-cells

AIMS

Thiazolidinediones (TZDs), ligands for peroxisome proliferator-activated receptor gamma, are antidiabetic agents that improve hyperglycemia by decreasing insulin resistance in obese diabetic animal models and patients with type 2 diabetes. We have studied whether pioglitazone, a TZD, can exert a direct effect against pancreatic beta-cell lipoapoptosis.

METHODS

MIN6 cells were cultured in medium containing either 5.6 (low glucose) or 25 mM glucose (high glucose) in the presence or absence of 0.5 mM palmitate for 48 h. We examined the effect of 10 microM pioglitazone on MIN6 cells on glucose-stimulated insulin secretion, cellular ATP, uncoupling protein-2 (UCP-2) mRNA expression, intracellular triglyceride content, reactive oxygen species production, the number of apoptotic cells and nuclear factor-kappaB (NF-kappaB) activity.

RESULTS

Pioglitazone recovered partly impaired glucose-stimulated insulin secretion and cellular ATP in MIN6 cell exposed to high glucose with 0.5 mM palmitate. Pioglitazone suppressed intracellular triglyceride accumulation in cells exposed to high glucose with 0.5 mM palmitate. Palmitate-induced upregulation of UCP-2 mRNA levels was suppressed by pioglitazone in a dose-dependent manner. Pioglitazone decreased palmitate-induced reactive oxygen species production in MIN6 cells by 24% and in mouse islet cells by 53%. Pioglitazone also decreased palmitate-induced NF-kappaB activity by 40% and protected beta-cells from palmitate-induced apoptosis by 22% in MIN6 cell.

CONCLUSIONS

Pioglitazone attenuated fatty acid-induced oxidative stress and apoptosis in pancreatic beta-cells. TZDs might be used as a mean for maintaining beta-cell survival and preserving capacity of insulin secretion in patients with diabetes mellitus.

Bone wax as a cause of foreign body reaction after lumbar disc surgery: a case report

This report describes a 45-year-old patient who was admitted to the hospital with complaints of low-back pain, lower extremity weakness, and difficulty in walking for the previous 6 mo. The patient's history revealed 2 lumbar-disc surgeries that were performed 1 y earlier. The patient underwent surgery at our hospital because of clinical symptoms and radiologic findings on magnetic resonance imaging. During the operation, 1 x 1 x 1 cm of bone wax that was compressing the dural sac and spinal root was extirpated from the surgical area. Bone wax use should be limited in spinal surgery because of the potential for compression and chronic inflammation.

« Abcès atypique » jugal après extraction de dents de sagesse: complication de l'utilisation de cire hémostatique

Bleeding is a common complication after third molar extraction. Hemostatic agents can be helpful in controlling intraoperative bleeding. Infection is another common complication. Horseley's wax is frequently used for bone surgery and less often for dental surgery. We report an unusual case of abscess formation in the jaw after third molar extraction. Surgical exploration of the abscess disclosed the presence of surgical wax in the center of a foreign body granuloma. We discuss the use of surgical wax and other local hemostatic agents and the subsequent risk of complications.

Haemostatic agents used in periradicular surgery: an experimental study of their efficacy and tissue reactions

AIM

To evaluate the haemostatic efficacy and the histologic tissue responses after the application of different haemostatic agents used in periradicular surgery.

METHODOLOGY

The study was conducted in the calvarium of six rabbits. Standardized bone defects (diameter 4 mm) were trephined, and different haemostatic agents were applied and compared with control defects: bone wax (left for 10 min), Stasis (ferric sulphate, left for 5 s), Expasyl (aluminium chloride, left for 2 min and left permanently in situ), and a combination of Expasyl (2 min) and Stasis (5 s). The sites were photographed before the application and after the removal of the haemostatic agents. Three independent examiners judged the initial and final bleeding (on the photographs) using a bleeding score for each site and treatment. The results were compared using Wilcoxon's signed rank test. For the histologic analysis, three animals were killed after 3 weeks and three animals after 12 weeks. Transverse, nondecalcified sections were stained with combined basic fuchsin and toluidine blue for descriptive histology.

RESULTS

The most efficient haemorrhage control was provided by Expasyl in combination with Stasis and by Expasyl alone, whereas bone wax had the weakest bleeding reduction effect. The histologic analysis after 3 weeks demonstrated an inflammatory and foreign body tissue response towards all haemostatic agents. At 12 weeks, this tissue response was less pronounced but still present in sites treated with bone wax or Expasyl. In general, the inflammatory tissue reactions were limited to the bone defects, and never extended into the surrounding tissues.

CONCLUSIONS

Expasyl alone or in combination with Stasis appeared to be the most efficient of tested agents to control the bleeding within the bony defects created in a rabbit calvarium model.

The use of local agents: bone wax, gelatin, collagen, oxidized cellulose

The use of local agents to achieve hemostasis is an old and complex subject in surgery. Their use is almost mandatory in spinal surgery. The development of new materials in chemical hemostasis is a continuous process that may potentially lead the surgeon to confusion. Moreover, the more commonly used materials have not changed in about 50 years. Using chemical agents to tamponade a hemorrhage is not free of risks. Complications are around the corner and can be due either to mechanical compression or to phlogistic effects secondary to the material used. This paper reviews about 20 animal and clinical published studies with regard to the chemical properties, mechanisms of action, use and complications of local agents.

Bone wax as a cause of a foreign body granuloma in a cranial defect: a case report

Bone wax was used to stop bleeding of the diploic vessels after harvesting cranial bone for reconstruction of an orbital floor defect. After five months a fistula in the overlying skin of the donor site appeared and was eventually surgically explored. Remnants of bone wax and surrounding inflammatory tissue were removed and the fistula was excised. Histological examination revealed a foreign body granuloma. The use of bone wax and possible alternative local haemostatic agents and their complications are discussed.

Bone wax foreign body granuloma in the mastoid

The sue of bone wax is commonly used to control bleeding during mastoid surgery. An unusual case of bone wax granuloma in the mastoid, with sigmoid sinus thrombosis, is reported. Although the use of bone wax in and around the mastoid is generally considered safe with few complications, caution should be exercised, particularly in infected fields and in patients known to have general immunohypersensitivity.

Is Bone-wax an injectable urologic material?

OBJECTIVE

Injection of endoscopic material for reflux and incontinence therapies became popular in urology because of its simplicity and repeatability. Research is going on to develop an ideal injectable material. In this experimental study we investigated whether the bone wax used for osteotomy hemostasis in orthopedic and neurosurgical operations could be used as an injectable material.

MATERIALS AND METHODS

A total of 20 rabbits were included in the study: 6 underwent a sham operation, and in the remaining 14 rabbits, 0.5 ml bone wax liquefied with n-butyl acetic acid was injected submucosally via a 20-gauge needle at three different points on the anterior bladder wall. Cystectomy was performed on the 15th day in 2 rabbits (group I), on the 60th day in 2 (group II) and on the 150th day in 10 (group III). 0.20 ml bone wax was also injected subcutaneously and intramuscularly 7 days before cystectomy in group III. Bladders were examined macroscopically and histopathologically. All animals' lungs, livers, kidneys, spleens and brains were also removed and examined histologically.

RESULTS

Submucosal swellings of bone wax maintained their localizations and shapes in all groups and all of the 42 bone-wax injection sites could be easily identified. Histologically, slight edema around the implant was seen in group I. In group II, collagen was increased around the implants and minimal hyperplasia of the epithelium overlaying bone wax was noted. 150 days after the injections, moderate collagen production and a mild increase in vascularity were seen around the implants. There was no macroscopic or microscopic evidence that implants migrated to locations other than the injection sites.

CONCLUSIONS

When injected to the bladder submucosa, bone wax seems to be inert and biocompatible, encouraging further research to develop it as an alternative agent in the endoscopic treatment of vesicoureteral reflux and sphincteric incontinence.

Adverse effects of bone wax in surgery of the orbit

The goal of this article is to establish the incidence and scope of adverse reactions to bone wax in a large orbital surgical series. We report two patients with bone wax granulomas of the orbit as a remote surgical complication. These are the first reported cases of adverse reactions to bone wax in the ophthalmic literature. A chart review was conducted on all patients from the University of British Columbia Orbit Clinic that had surgery with temporary or permanent removal of orbital bone. Two patients with bone wax granulomas were identified. In one case, intraoperative cultures grew Staphylococcus aureus, confirming that the wax may indeed act as a nidus for infection. No cases of pseudoarthrosis have occurred. This syndrome of chronic granulomatous giant cell foreign body inflammation has characteristic clinical, radiologic, and histopathologic features. The literature regarding adverse reactions to bone wax is reviewed, and specific implications for orbital surgery are discussed.

Surgical bone wax causing epistaxis

A case of recurrent epistaxis caused by bone wax in the nasal cavity is reported. This is the first reported case of a nasal complication due to surgical bone wax.

Foreign body reactions and an associated histological artefact due to bone wax

Bone wax has been used since the turn of the century as a mechanical aid to haemostasis following surgical procedures. That it may produce a foreign body giant cell reaction in a significant proportion of cases is well known. The occurrence of this material in specimens received in the laboratory is poorly documented. Four cases are described to bring attention to this exogenous agent which, it is suggested, should feature in tables of pigments and other materials occurring in tissue specimens.

Assessment in rats of a new bioerodible bone-wax-like polymer

Holes drilled in rats' skull, iliac crest, and tibia were filled with beeswax or with a new, wax-like, bioerodible polyorthoester (Alzamer). Empty drill-holes served as controls. In addition, beeswax and polyorthoester were deposited between the left and the right oblique abdominal muscles, respectively. In muscle, both the beeswax and polyorthoester elicited a transient foreign body reaction. The beeswax was not resorbed in bone or muscle, whereas the polyorthoester was. Bone healing was inhibited in the iliac crest and the tibiae filled with beeswax, whereas holes filled with polyorthoester healed readily.

The promotional effect of bone wax on experimental Staphylococcus aureus osteomyelitis

The consequences of using surgical bone wax are not well studied. We evaluated the infection-promoting potential of sterile bone wax in a rat model of chronic Staphylococcus aureus osteomyelitis. The addition of bone wax greatly reduced the quantitative bacterial inoculum (log colony-forming units) required to establish chronic osteomyelitis in 50% and 100% of challenged animals. The 50% infection rate was reduced from log 6.9 to 2.6 and the 100% infection rate from 8.2 to 4.4, respectively (p less than 0.015, t test for parallelism). Separate experiments were done 10 to 30 minutes after inoculation with only log 6.4 staphylococci. Tibiae of animals that received bone wax yielded more organisms than those that did not (log 2.76 +/- 0.68 versus 1.72 +/- 0.94, p less than 0.01). At 24 hours quantitative colony counts were not significantly different whether animals received wax or not (log 5.02 +/- 0.42 versus 4.43 +/- 0.65, p greater than 0.09). These studies suggest that the routine surgical use of bone wax should be reassessed.