A Retrospective Cohort Study of the Effect of Gout on Mortality Among Patients with a History of Kidney Transplantation

Background

Kidney transplantation is associated with increased prevalence of gout. However, evidence of the effect of gout on long-term kidney transplantation outcomes is mixed. This study examined mortality risk among patients with a history of kidney transplantation with vs. without gout.

Material/Methods

A retrospective study was conducted using Medicare Fee-for-Service administrative claims of patients with a history of kidney transplantation. Cox proportional hazards models determined the effect of gout on all-cause mortality, controlling for confounders, including comorbid mortality risk, via the Charlson Comorbidity Index. Because the relationships between gout and components of the Charlson Comorbidity Index are also debated, 3 different model assumptions were used: 1) gout shares a common cause with these comorbidities, 2) gout is upstream of these comorbidities, 3) the effect of gout on mortality is modified by these comorbidities.

Results

Gout increased the risk of all-cause mortality in the unadjusted model (hazard ratio: 1.44, 95% CI 1.27–1.63) and after adjustment for demographics and transplant vintage (hazard ratio: 1.16, 95% CI 1.02–1.32). Gout was not a significant risk after adjustment for baseline Charlson Comorbidity Index (hazard ratio: 1.03, 95% CI 0.90–1.17). Gout was associated with greater mortality among patients without baseline comorbidities (Charlson Comorbidity Index=0; hazard ratio: 3.48, 95% CI 1.27–9.57) in the stratified model.

Conclusions

Among patients with a history of kidney transplantation, gout did not have an independent effect on all-cause mortality. However, gout was a predictor of mortality among patients with no comorbidities, suggesting that gout is an early warning sign of poor health in kidney transplantation patients.

Immunosuppressant Use and Gout in the Prevalent Solid Organ Transplantation Population

INTRODUCTION

Gout is a common comorbidity among solid organ transplantation patients and is usually attributed to the use of cyclosporine. This study aims to evaluate the prevalence of gout among solid organ transplantation patients to determine the prevalence in the tacrolimus era.

RESEARCH QUESTIONS

To what degree is cyclosporine still used among prevalent solid organ transplantation patients? How prevalent is gout in the solid organ transplantation population not being treated by cyclosporine?

METHODS

Immunosuppressant regimens and gout prevalence among prevalent solid organ transplantation patients were assessed using retrospective claims data for a representative sample of commercially insured patients. For comparison to the prevalent solid organ transplantation population, immunosuppressant use at time of transplantation was compiled from published reports.

RESULTS

Between 2012 and 2016, the use of cyclosporine declined while use of tacrolimus increased, with greater cyclosporine use among prevalent versus incident solid organ transplantation patients. The prevalence of gout was 18.3%, 9.3%, and 9.1% for solid organ transplantation patients on cyclosporine, tacrolimus, and neither, respectively. Among all solid organ transplantation patients with gout, 66.6% and 21.5% were on tacrolimus versus cyclosporine. The prevalence of gout among noncyclosporine solid organ transplantation patients was significantly higher than in the general population without solid organ transplantation.

DISCUSSION

Despite declining cyclosporine use, gout prevalence remains high, with the majority of patients with gout receiving tacrolimus rather than cyclosporine. In summary, gout remains a frequent comorbidity of solid organ transplantation.

Prevalence of Gout in the Surviving United States Solid Organ Transplantation Population

PURPOSE

Although incidence and survival are frequent topics within the solid organ transplantation (SOT) literature, the size of the surviving SOT population is not well known. Existing studies of gout in patients with SOT have focused on the incident SOT population. This analysis was performed to characterize the prevalent SOT population and the prevalence of gout within it.

METHODS

This study includes the 2017 United States (US) population size of recipients of kidney, heart, liver, and lung transplants that was estimated by combining primary transplant recipient cohort sizes (1988-2017) with previously published survival rates for each annual cohort's time since transplantation (0-29 years). Gout among prevalent patients with SOT was assessed using Medicare and commercial claims.

RESULTS

A total of 637,231 US patients received a primary kidney (393,953), liver (142,186), heart (66,637), or lung (34,455) transplant between 1988 and 2017. An estimated 356,000 (55.8%) recipients were alive in 2017 (233,000 kidney; 78,700 liver; 29,300 heart; 14,700 lung). Gout was identified in 11% of prevalent patients with SOT in 2016. Higher rates of gout were seen in recipients of kidney (13.1%) and heart (12.7%) compared to recipients of liver (6.7%) and lung (5.6%) (P < .0001 in both datasets). Active diagnosed gout prevalence in the US population without a SOT history was 1.1% in 2016.

CONCLUSIONS

Hundreds of thousands of US patients are living with a transplanted organ today and these numbers are likely to increase. In patients with SOT, gout is a frequent comorbidity of which physicians should be aware. This study suggests a markedly higher rate of gout among transplant recipients compared to the general US population.

Gout Severity in Recipients of Kidney Transplant

PURPOSE

This retrospective analysis of medical chart data was performed to compare severity and treatment of gout in patients with or without a history of kidney transplantation (KT).

METHODS

Via an online survey, a panel of board-certified US nephrologists (N = 104) provided the following deidentified chart data for their 3 most recent patients with gout: age, sex, serum uric acid, numbers of swollen or tender joints, visible tophi, gout flare events (prior 12 months), gout drug treatment history, and KT history. The presence of "severe, uncontrolled gout" was defined as: serum uric acid ≥ 7.0 mg/dL, ≥1 tophi and ≥2 flares in the last 12 months, and history of xanthine oxidase inhibitor treatment.

RESULTS

Twenty-five out of 312 (8.0%) gout patients had a history of KT. Univariate analysis found that patients with gout and history of kidney transplants had: greater prevalence of severe uncontrolled gout (27% vs 8%, P = .007) and tophi (36% vs 17%, P = .030), and higher rates of failure or physician perceived contraindication to allopurinol (44% vs 23%, P = .028).

CONCLUSION

This study provides preliminary evidence that gout in patients with history of KT is more severe and poses greater challenges to pharmacologic management. Although gout has been linked to worse outcomes among kidney recipients in the literature, there are presently no publications on gout severity among patients with KT in comparison to other patients with gout. Further investigation of disease severity and appropriate, effective treatment options in recipients of kidney transplant with a diagnosis of gout, especially prior to the transplant, is warranted.

Efficacy and safety of diclofenac sodium 2% topical solution for osteoarthritis of the knee: a randomized, double-blind, vehicle-controlled, 4 week study

OBJECTIVE

Nonsteroidal anti-inflammatory drugs (NSAIDs) are standard therapy for osteoarthritis (OA). Topically applied NSAIDs reduce systemic exposure compared with oral NSAIDS, and European guidelines recommend their use. The NSAID diclofenac is available in a range of topical formulations. Diclofenac 1% gel and 1.5% four times daily and 2% twice daily (BID) solutions are approved to reduce pain from OA of the knee(s). The objective of this study was to investigate the efficacy and safety of diclofenac sodium 2% topical solution BID versus vehicle control solution for treating pain associated with OA of the knee.

RESEARCH DESIGN AND METHODS

A phase II, 4 week, randomized, double-blind, parallel-group, two-arm, vehicle-controlled study compared pain relief with diclofenac sodium 2% topical solution versus control (vehicle only) in patients aged 40 to 85 years with radiographically confirmed primary OA of the knee.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov identifier NCT01119898.

MAIN OUTCOME MEASURES

The primary efficacy outcome was change from baseline to the final visit in the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain subscale. Secondary outcomes included additional WOMAC subscales and patient global assessment of OA. Treatment-emergent adverse events (TEAEs), skin irritation, and vital signs were assessed and collected throughout the study.

RESULTS

Of 260 patients randomized, 259 received ≥1 dose of study drug. Significantly greater reductions in least-squares mean (standard error) WOMAC pain scores were observed for diclofenac-treated (-4.4 [0.4]) versus vehicle-treated patients (-3.4 [0.4]) at the final visit (p = 0.040). The most commonly reported TEAEs were administration site conditions. The vehicle-treated group experienced slightly more TEAEs than the active treatment group (38.8% vs. 31.5%). No serious adverse events were reported.

CONCLUSIONS

Administration of diclofenac sodium 2% topical solution BID resulted in significantly greater improvement in pain reduction in patients with OA of the knee versus vehicle control and was generally well tolerated.

Onset and durability of pain relief in knee osteoarthritis: pooled results from two placebo trials of naproxen/esomeprazole combination and celecoxib

OBJECTIVE

To further characterize time-to-first pain relief, effect size, correlations between various outcome measures and durability of relief for single-tablet naproxen 500 mg/esomeprazole 20 mg (NAP/ESO) given twice daily and celecoxib (CEL) (200 mg) given once daily versus placebo in knee osteoarthritis (OA).

METHODS

Unpublished data from two double-blind, double-dummy, placebo-controlled trials in which patients aged ≥50 years with knee OA were randomized to NAP/ESO (n = 487), CEL (n = 486) or placebo (n = 246) were pooled (NCT00664560 and NCT00665431). Acute response endpoints: 1) Time to first significant pain response, 2) Western Ontario and McMaster Osteoarthritis Index (WOMAC) pain subscale and 3) American Pain Society Patient Outcome Questionnaire (APS-POQ) scores. Sustainability endpoints: 1) Routine Assessment of Patient Index Data (RAPID3) and 2) WOMAC Stiffness, Pain and Total scores; and Patient Global Assessment (PGA) at 6 and 12 weeks. Effect sizes for all measures were calculated. Rescue pain medication use also was analyzed, as was the correlation of WOMAC to RAPID3.

RESULTS

NAP/ESO produced statistically significant decreases in WOMAC Pain on Days 2-7 and at Weeks 6 and 12 (all p < 0.05); most APS-POQ pain assessments with NAP/ESO were significantly improved on Days 2-7 compared with placebo (all p < 0.05). A good or excellent response occurred in a median of 6 days. RAPID3 and WOMAC total/stiffness/function/PGA scores decreased significantly at Weeks 6 and 12 (all p < 0.05). Placebo-adjusted WOMAC pain effect sizes were 0.44, 0.34 and 0.25 at Day 7, week 6 and week 12, respectively. RAPID3 to WOMAC total and WOMAC pain to RAPID3: Pain scores were highly correlated at 6 and 12 weeks (correlation coefficients >0.80). No significant differences in overall responses were found between CEL and NAP/ESO.

CONCLUSION

Naproxen/esomeprazole produced a significant absolute moderate early pain response, which was maintained for 12 weeks. RAPID3 was found to be highly correlated with the typical OA measure (WOMAC) and might be a useful clinical tool for measuring NSAID response. NCT00664560: https://clinicaltrials.gov/ct2/show/NCT00664560, NCT00665431: https://www.clinicaltrials.gov/ct2/show/NCT00665431.

Onset and durability of pain relief in knee osteoarthritis: Pooled results from two placebo trials of naproxen/esomeprazole combination and celecoxib

OBJECTIVE

To further characterize time-to-first pain relief, effect size, correlations between various outcome measures and durability of relief for single-tablet naproxen 500 mg/esomeprazole 20 mg (NAP/ESO) given twice daily and celecoxib (CEL) (200 mg) given once daily versus placebo in knee osteoarthritis (OA).

METHODS

Unpublished data from two double-blind, double-dummy, placebo-controlled trials in which patients aged ≥ 50 years with knee OA were randomized to NAP/ESO (n = 487), CEL (n = 486) or placebo (n = 246) were pooled (NCT00664560 and NCT00665431). Acute response endpoints: 1) Time to first significant pain response, 2) Western Ontario and McMaster Osteoarthritis Index (WOMAC) pain subscale and 3) American Pain Society Patient Outcome Questionnaire (APS-POQ) scores. Sustainability endpoints: 1) Routine Assessment of Patient Index Data (RAPID3) and 2) WOMAC Stiffness, Pain and Total scores; and Patient Global Assessment (PGA) at 6 and 12 weeks. Effect sizes for all measures were calculated. Rescue pain medication use also was analyzed, as was the correlation of WOMAC to RAPID3.

RESULTS

NAP/ESO produced statistically significant decreases in WOMAC Pain on Days 2-7 and at Weeks 6 and 12 (all p < 0.05); most APS-POQ pain assessments with NAP/ESO were significantly improved on Days 2-7 compared with placebo (all p < 0.05). A good or excellent response occurred in a median of 6 days. RAPID3 and WOMAC total/stiffness/function/PGA scores decreased significantly at Weeks 6 and 12 (all p < 0.05). Placebo-adjusted WOMAC pain effect sizes were 0.44, 0.34 and 0.25 at Day 7, week 6 and week 12, respectively. RAPID3 to WOMAC total and WOMAC pain to RAPID3: Pain scores were highly correlated at 6 and 12 weeks (correlation coefficients >0.80). No significant differences in overall responses were found between CEL and NAP/ESO.

CONCLUSION

Naproxen/esomeprazole produced a significant absolute moderate early pain response, which was maintained for 12 weeks. RAPID3 was found to be highly correlated with the typical OA measure (WOMAC) and might be a useful clinical tool for measuring NSAID response. NCT00664560: https://clinicaltrials.gov/ct2/show/NCT00664560, NCT00665431: https://www.clinicaltrials.gov/ct2/show/NCT00665431.

Gastroprotective efficacy and safety of single-tablet ibuprofen/famotidine vs ibuprofen in older persons

OBJECTIVES

A combination tablet of ibuprofen 800 mg and famotidine 26.6 mg given three times daily is effective for the treatment of rheumatoid arthritis and osteoarthritis and decreases the risk of developing upper gastrointestinal (GI) ulcers. This analysis evaluated the gastroprotective efficacy and safety of the single-tablet combination of ibuprofen/famotidine compared with ibuprofen alone on the basis of age and the presence of one or more risk factors for development of upper GI ulcer.

METHODS

Pooled data from the 24-week, randomized, double-blind, parallel-group REDUCE-1 and REDUCE-2 trials were used. Endoscopies were performed in patients aged 40-80 years. The proportion of patients who developed ≥ 1 upper GI ulcer during treatment with ibuprofen/famotidine versus ibuprofen alone stratified on the basis of age (< 60 or ≥ 60 years) was evaluated. Further, analyses were performed on additional risk factors for ulcer development.

RESULTS

Gastroprotective efficacy of the combination was not affected by age. Pooled results demonstrated statistically significantly fewer upper GI (10.0 vs 19.5%, p < 0.0001), gastric (8.9 vs 16.8%, p = 0.0004), and duodenal ulcers (1.1 vs 5.4%, p < 0.0001) in patients < 60 years treated with ibuprofen/famotidine versus ibuprofen alone compared with 12.9 vs 26.6% (p = 0.0002), 11.9 vs 23.4% (p = 0.0011), and 1.0 vs 4.5% (p = 0.0096), respectively, in patients ≥ 60 years. The ibuprofen/famotidine combination provided nearly 51 and 59% reduction in the risk of developing a GI ulcer in patients <60 years and ≥ 60 of age, respectively. Efficacy was maintained in the presence of additional risk factors, as well.

CONCLUSIONS

These results indicate that the fixed-combination of ibuprofen/famotidine provides gastroprotection in those of older age, with or without additional risk factors for the development of upper GI ulcers, as compared with ibuprofen alone. US National Institutes of Health registry, http://www.clinicaltrials.gov, NCT00450658 and NCT00450216.

Improvement Thresholds for Morning Stiffness Duration in Patients Receiving Delayed- Versus Immediate-Release Prednisone for Rheumatoid Arthritis

BACKGROUND

Morning stiffness, a common patient reported symptom in rheumatoid arthritis, is associated with an increase in early morning inflammatory cytokines and significant disability. Little is known about categorical morning stiffness responses to glucocorticoid use in rheumatoid arthritis patients. Chronic pain threshold models have indicated previously that response rates of 15% to 30% indicate minimally important relief, 40% to 50% indicate substantial pain relief, and greater than 70% represents extensive pain relief. The objective of the present analysis was to assess differences in the percentages of patients achieving 25%(minimally important change), 50% (substantial change), and 75% (extensive change) reduction in the duration of patient-reported morning stiffness between patients receiving DR- and IR-prednisone in the Circadian Administration of Prednisone in Rheumatoid Arthritis (CAPRA-1) trial.

MATERIALS AND METHODS

The CAPRA-1 trial was a 12-week, double-blind study followed by an additional 9-month open-label extension. Patients in the CAPRA-1 trial were randomized to IR-prednisone in the morning or DR-prednisone at bedtime in addition to stable disease modifying antirheumatic drug therapy. After the double-blind phase, patients randomized to IR-prednisone (N =110) were switched to DR-prednisone and followed at 3, 6, and 9 months in an open-label extension phase. Patients originally randomized to DR-prednisone (N = 97) continued that therapy in the open-label extension. Patient morning stiffness diary entries from 4 weeks before and 4 weeks after each scheduled visit were analyzed over 1 year for threshold response. The number of patients reaching threshold response (25%, 50%, and 75% improvement) and time to morning stiffness response were examined.

RESULTS

The DR-prednisone arm had significantly more responders in all three morning stiffness threshold response categories at the end of the double-blind period compared with IR-prednisone (p ≤ 0.05). Patients who switched from IR- to DR-prednisone in the open-label extension had comparable responses in all categories within 3 months and significantly shorter time to response versus patients already receiving DR-prednisone.

DISCUSSION

DR-prednisone produced significantly higher morning stiffness response rates compared with IR prednisone, as defined by 25%, 50%, and 75% improvement thresholds, at week 12. The time to reach these thresholds was quicker with DR-prednisone, and patients who switched to DR-prednisone from IR-prednisone achieved responses comparable to the continuous DR-prednisone group over 9 months of therapy. This analysis is the first to assess time-to-event and percentage threshold morning stiffness responses to differently timed glucocorticoid therapy and propose clinically meaningful response rates in RA patients.

One-year open-label safety evaluation of the fixed combination of ibuprofen and famotidine with a prospective analysis of dyspepsia

OBJECTIVE

To assess the long-term safety of the single-tablet combination of ibuprofen 800 mg and famotidine 26.6 mg.

RESEARCH DESIGN AND METHODS

A phase 3b open-label study (NCT00984815) was conducted in 86 adults requiring daily non-steroidal anti-inflammatory drug (NSAID) administration for ≥12 months. The combination tablet of ibuprofen/famotidine was self-administered orally three times daily for up to 54 consecutive weeks. Adverse events (AEs) were collected beginning at the first dose and continued through completion (54 weeks). The Severity of Dyspepsia Assessment (SODA) questionnaire was completed by patients to assess tolerability.

RESULTS

Most patients (65%) finished the trial, with 76% contributing data at 6 months, and 21% withdrew due to adverse effects. Overall and gastrointestinal AE discontinuation rates (21% and 13%, respectively) were lower than that previously reported with ibuprofen 2400 mg given alone. Each of the SODA subscale scores demonstrated improvement by week 6 and improved statistically significantly at week 24 and week 54. Of the cardiovascular AEs, hypertension was reported most frequently (9/86, 9.3%), with 3.5% determined to be drug related. Twelve serious AEs were reported by 9 of 86 (10%) patients; two were considered possibly related to the study medication (unstable angina and gastric ulcer). There were no reports of serious gastrointestinal or CV complications. Most AEs were mild or moderate in severity and not considered drug related.

CONCLUSIONS

These data, together with previously reported findings of a significant decrease in upper gastrointestinal endoscopic ulcer rate at 6 months, support the overall safety, compliance, and tolerability of this single-tablet formulation.

One-year safety of ibuprofen/famotidine fixed combination versus ibuprofen alone: pooled analyses of two 24-week randomized, double-blind trials and a follow-on extension

OBJECTIVE

To evaluate the safety of the fixed combination of ibuprofen and famotidine compared with ibuprofen alone from two 24-week, multicenter, double-blind trials designed to evaluate the comparative incidence of endoscopically documented upper gastrointestinal ulcers and a 28-week double-blind extension study.

RESEARCH DESIGN AND METHODS

Safety was analyzed by pooling data from the two double-blind trials and the follow-on study. Safety was assessed by monitoring the incidence, causality, and severity of adverse events (AEs).

RESULTS

In the pivotal efficacy and safety trials, discontinuation rates due to any cause and dyspepsia were significantly lower for the ibuprofen/famotidine combination versus ibuprofen alone. Other than dyspepsia, gastrointestinal and cardiovascular AEs of special interest were similar. Events judged to be treatment related were significantly lower with the ibuprofen/famotidine combination (20.6% vs. 25%). In the safety extension population, there were no differences in the discontinuation rates and the reporting of AEs or serious AEs (SAEs) between the two groups. Gastrointestinal-related events were similar between the groups. Incidence of cardiovascular-related AEs of special interest were 11% (ibuprofen/famotidine) and 2% (ibuprofen) (p=0.06), possibly due to a higher number of rheumatoid arthritis patients in the combination group. Of these, 80% were reports of hypertension (8% ibuprofen/famotidine vs. 2% ibuprofen). Three cases of hypertension in the ibuprofen/famotidine group were considered treatment related. The probability of a cardiovascular event decreased during days 112-167 of treatment and remained low with continued treatment.

CONCLUSIONS

One-year safety data from two pivotal trials and a long-term extension study indicate that the ibuprofen/famotidine combination demonstrates a favorable gastrointestinal safety profile and more patients continued on therapy compared to ibuprofen alone. No new safety signals have been identified. These data offer additional evidence supporting a new therapeutic option to improve gastrointestinal safety and adherence for patients who require long-term ibuprofen.

The CHOICE trial: adalimumab demonstrates safety, fistula healing, improved quality of life and increased work productivity in patients with Crohn's disease who failed prior infliximab therapy

BACKGROUND

Adalimumab induces and maintains remission in adults with Crohn's disease.

AIM

To evaluate safety, fistula healing, quality of life and work productivity in adalimumab-treated patients who failed infliximab, including primary nonresponders.

METHODS

After a ≥8-week infliximab washout, patients with moderate-to-severe Crohn's disease received open-label adalimumab as induction (160/80 mg at weeks 0/2) and maintenance (40 mg every other week) therapies. At/after 8 weeks, patients with flare/nonresponse could receive weekly therapy. Minimum study duration was 8 weeks, continuing until the commercial availability of adalimumab for Crohn's disease.

RESULTS

Of 673 patients enrolled, 17% were infliximab primary nonresponders and 83% were initial responders. Three percent of patients had serious infections (mainly abscesses). Complete fistula healing was achieved by 34/88 (39%) patients with baseline fistulas. Improvements in quality of life and work productivity were sustained from week 4 to week 24 for all patients, as well as the subgroup of primary nonresponders.

CONCLUSIONS

Blinded clinical trials have shown adalimumab to be both an effective first-line therapy for anti-TNF-naïve patients and an important treatment option for infliximab-refractory or -intolerant patients. This trial presents open-label experience to support further the safety and effectiveness of adalimumab in patients who failed infliximab therapy, including primary nonresponders (NCT00338650).

Adalimumab for the treatment of fistulas in patients with Crohn's disease

OBJECTIVE

To evaluate the efficacy of adalimumab in the healing of draining fistulas in patients with active Crohn's disease (CD).

DESIGN

A phase III, multicentre, randomised, double-blind, placebo controlled study with an open-label extension was conducted in 92 sites.

PATIENTS

A subgroup of adults with moderate to severely active CD (CD activity index 220-450) for >or=4 months who had draining fistulas at baseline.

INTERVENTIONS

All patients received initial open-label adalimumab induction therapy (80 mg/40 mg at weeks 0/2). At week 4, all patients were randomly assigned to receive double-blind placebo or adalimumab 40 mg every other week or weekly to week 56 (irrespective of fistula status). Patients completing week 56 of therapy were then eligible to enroll in an open-label extension.

MAIN OUTCOME MEASURES

Complete fistula healing/closure (assessed at every visit) was defined as no drainage, either spontaneous or with gentle compression.

RESULTS

Of 854 patients enrolled, 117 had draining fistulas at both screening and baseline (70 randomly assigned to adalimumab and 47 to placebo). The mean number of draining fistulas per day was significantly decreased in adalimumab-treated patients compared with placebo-treated patients during the double-blind treatment period. Of all patients with healed fistulas at week 56 (both adalimumab and placebo groups), 90% (28/31) maintained healing following 1 year of open-label adalimumab therapy (observed analysis).

CONCLUSIONS

In patients with active CD, adalimumab therapy was more effective than placebo for inducing fistula healing. Complete fistula healing was sustained for up to 2 years by most patients in an open-label extension trial.

Adalimumab for maintenance treatment of Crohn's disease: results of the CLASSIC II trial

BACKGROUND

Adalimumab induced clinical remission after four weeks in patients with active Crohn's disease in the CLASSIC I trial.

OBJECTIVE

To evaluate long term efficacy and safety of adalimumab maintenance therapy in Crohn's disease in a follow-on randomised controlled trial (CLASSIC II).

METHODS

In the preceding CLASSIC I trial, 299 patients with moderate to severe Crohn's disease naive to tumour necrosis factor antagonists received induction therapy with adalimumab 40 mg/20 mg, 80 mg/40 mg, or 160 mg/80 mg, or placebo, at weeks 0 and 2. In all, 276 patients from CLASSIC I enrolled in CLASSIC II and received open-label adalimumab 40 mg at weeks 0 (week 4 of CLASSIC I) and 2; 55 patients in remission at both weeks 0 and 4 were re-randomised to adalimumab 40 mg every other week, 40 mg weekly, or placebo for 56 weeks. Patients not in remission at both weeks 0 and 4 were enrolled in an open-label arm and received adalimumab 40 mg every other week. With non-response or flare, these patients could have their dosages increased to 40 mg weekly. Patients in the randomised arm with continued non-response or disease flare could switch to open-label adalimumab 40 mg every other week and again to 40 mg weekly. The primary end point was maintenance of remission (CDAI <150) in randomised patients through week 56.

RESULTS

Of 55 patients randomised at week 4, 79% who received adalimumab 40 mg every other week and 83% who received 40 mg weekly were in remission at week 56, v 44% for placebo (p<0.05). In all, 204 patients entered the open-label arm. Of these, 93 (46%) were in clinical remission at week 56. Adalimumab was generally well-tolerated in all patients.

CONCLUSIONS

Adalimumab induced and maintained clinical remission for up to 56 weeks in patients with moderate to severe Crohn's disease naive to anti-TNF treatment.

Adalimumab induction therapy for Crohn disease previously treated with infliximab: a randomized trial

BACKGROUND

Adalimumab, a fully human tumor necrosis factor (TNF) antagonist, is an effective treatment for patients with Crohn disease who are naive to the chimeric TNF antagonist, infliximab. No anti-TNF agent has been evaluated prospectively in patients with Crohn disease who had responded to another anti-TNF agent and then lost that response or were intolerant of the agent.

OBJECTIVE

To determine whether adalimumab induces remissions more frequently than placebo in adult patients with Crohn disease who have symptoms despite infliximab therapy or who cannot take infliximab because of adverse events.

DESIGN

4-week, randomized, double-blind, placebo-controlled trial (November 2004 to December 2005).

SETTING

52 sites in the United States, Canada, and Europe.

PATIENTS

325 adults 18 to 75 years of age who had a history of Crohn disease for 4 months or more that was moderate to severe at baseline (Crohn's Disease Activity Index [CDAI] score, 220 to 450 points).

INTERVENTION

Patients were randomly assigned to receive induction doses of adalimumab, 160 mg and 80 mg, at weeks 0 and 2, respectively, or placebo at the same time points.

MEASUREMENTS

The primary end point was induction of remission at week 4. Decreases in CDAI score by 70 or more and 100 or more points (secondary end points) were also measured.

RESULTS

A total of 301 patients completed the trial. Twenty-one percent (34 of 159) of patients in the adalimumab group versus 7% (12 of 166) of those in the placebo group achieved remission at week 4 (P < 0.001). The absolute difference in clinical remission rates was 14.2 percentage points (95% CI, 6.7 to 21.6 percentage points). A 70-point response occurred at week 4 in 52% (82 of 159) of patients in the adalimumab group versus 34% (56 of 166) of patients in the placebo group (P = 0.001). The absolute difference in 70-point response rates was 17.8 percentage points (CI, 7.3 to 28.4 percentage points). Two of 159 patients in the adalimumab group and 4 of 166 patients in the placebo group discontinued treatment because of adverse events. No patients in the adalimumab group and 4 of 166 patients in the placebo group had a serious infection.

LIMITATIONS

The trial did not directly compare alternative active treatments and did not evaluate maintenance of response or long-term immunogenicity of adalimumab.

CONCLUSION

Adalimumab induces remissions more frequently than placebo in adult patients with Crohn disease who cannot tolerate infliximab or have symptoms despite receiving infliximab therapy. For more information on adalimumab in Crohn disease, click here. ClinicalTrials.gov registration number: NCT00105300.

Adalimumab for maintenance of clinical response and remission in patients with Crohn's disease: the CHARM trial

BACKGROUND & AIMS

This study evaluated the efficacy and safety of adalimumab, a fully human, anti-tumor necrosis factor monoclonal antibody administered subcutaneously, in the maintenance of response and remission in patients with moderate to severe Crohn's disease (CD).

METHODS

Patients received open-label induction therapy with adalimumab 80 mg (week 0) followed by 40 mg (week 2). At week 4, patients were stratified by response (decrease in Crohn's Disease Activity Index > or =70 points from baseline) and randomized to double-blind treatment with placebo, adalimumab 40 mg every other week (eow), or adalimumab 40 mg weekly through week 56. Co-primary end points were the percentages of randomized responders who achieved clinical remission (Crohn's Disease Activity Index score <150) at weeks 26 and 56.

RESULTS

The percentage of randomized responders in remission was significantly greater in the adalimumab 40-mg eow and 40-mg weekly groups versus placebo at week 26 (40%, 47%, and 17%, respectively; P < .001) and week 56 (36%, 41%, and 12%, respectively; P < .001). No significant differences in efficacy between adalimumab eow and weekly were observed. More patients receiving placebo discontinued treatment because of an adverse event (13.4%) than those receiving adalimumab (6.9% and 4.7% in the 40-mg eow and 40-mg weekly groups, respectively).

CONCLUSIONS

Among patients who responded to adalimumab, both adalimumab eow and weekly were significantly more effective than placebo in maintaining remission in moderate to severe CD through 56 weeks. Adalimumab was well-tolerated, with a safety profile consistent with previous experience with the drug.

Safety analyses of adalimumab (HUMIRA) in global clinical trials and US postmarketing surveillance of patients with rheumatoid arthritis

OBJECTIVE

To assess the safety of adalimumab in global clinical trials and postmarketing surveillance among patients with rheumatoid arthritis (RA).

METHODS

Safety data for adalimumab treated patients from randomised controlled trials, open label extensions, and two phase IIIb open label trials were analysed. In addition, postmarketing spontaneous reports of adverse events in the United States were collected following Food and Drug Administration approval of adalimumab on 31 December 2002.

RESULTS

As of 15 April 2005, the RA clinical trial safety database analysed covered 10,050 patients, representing 12,506 patient-years (PYs) of adalimumab exposure. The rate of serious infections, 5.1/100 PYs, was comparable to that reported on 31 August 2002 (4.9/100 PYs), and to published reports of RA populations naive to anti-tumour necrosis factor (TNF) therapy. Following implementation of tuberculosis (TB) screening in clinical trials, the rate of TB decreased. There were 34 cases of TB as of this analysis (0.27/100 PYs). The standardised incidence ratio for lymphoma was 3.19 (95% CI 1.78 to 5.26), consistent with the observed increased incidence in the general RA population. As of 30 June 2005, there were an estimated 78 522 PYs of exposure to adalimumab in the US postmarketing period. Seventeen TB cases were spontaneously reported (0.02/100 PYs) from the US. Rates of other postmarketing events of interest, such as congestive heart failure, systemic lupus erythematosus, opportunistic infections, blood dyscrasias, lymphomas, and demyelinating disease, support observations from clinical trials.

CONCLUSION

Analyses of these data demonstrate that long term adalimumab treatment is generally safe and well tolerated in patients with RA.

Effects of celecoxib and naproxen on renal function in nonazotemic patients with cirrhosis and ascites

Nonselective inhibition of cyclooxygenase (COX) by nonsteroidal anti-inflammatory drugs frequently induces renal failure in decompensated cirrhosis. Studies in experimental cirrhosis suggest that selective inhibitors of the inducible isoform COX-2 do not adversely affect renal function. However, very limited information is available on the effects of these compounds on renal function in human cirrhosis. This investigation consists of a double-blind, randomized, placebo-controlled trial aimed at comparing the effects of the selective COX-2 inhibitor celecoxib (200 mg every 12 hours for a total of 5 doses) on platelet and renal function and the renal response to furosemide (40 mg intravenously) with those of naproxen (500 mg every 12 hours for a total of 5 doses) and placebo in 28 patients with cirrhosis and ascites. A significant reduction (P < .05) in glomerular filtration rate (113 +/- 27 to 84 +/- 22 mL/min), renal plasma flow (592 +/- 158 to 429 +/- 106 mL/min) and urinary prostaglandin E(2) excretion (3430 +/- 430 to 2068 +/- 549 pg/min) and suppression of the diuretic (urine volume: 561 +/- 128 to 414 +/- 107 mL/h) and natriuretic (urine sodium: 53 +/- 13 to 34 +/- 10 mEq/h) responses to furosemide were observed in the group of patients treated with naproxen but not in the other two groups. Naproxen, but not celecoxib or placebo, significantly inhibited platelet aggregation (72% +/- 8% to 47% +/- 8%, P < .05) and thromboxane B(2) production (41 +/- 12 to 14 +/- 5 pg/mL, P < .05). In conclusion, our results indicate that short-term administration of celecoxib does not impair platelet and renal function and the response to diuretics in decompensated cirrhosis. Further studies are needed to evaluate the long-term safety of this drug in cirrhosis.

Reduced incidence of upper gastrointestinal ulcer complications with the COX-2 selective inhibitor, valdecoxib

AIM

In a predefined analysis, data were pooled from eight blinded, randomized, controlled trials, and separately from three long-term, open-label trials to determine the rate of upper gastrointestinal ulcer complications with the cyclo-oxygenase-2 selective inhibitor, valdecoxib, vs. non-selective non-steroidal anti-inflammatory drugs.

METHODS

In randomized, controlled trials, 7434 osteoarthritis and rheumatoid arthritis patients received placebo (n = 973), valdecoxib 5-80 mg daily (n = 4362), or a non-selective non-steroidal anti-inflammatory drug (naproxen, ibuprofen or diclofenac; n = 2099) for 12-26 weeks. In long-term, open-label trials, 2871 patients received valdecoxib 10-80 mg daily for up to 1 year. All potential events were reviewed by a blinded, independent review committee based on a priori definitions of ulcer complications (perforations, obstructions, bleeds).

RESULTS

In randomized, controlled trials, 19 of 955 potential events were adjudicated to be ulcer complications. Valdecoxib was associated with a significantly lower ulcer complication rate than non-selective non-steroidal anti-inflammatory drugs (0.68% vs. 1.96%, all patients; 0.29% vs. 2.08%, non-aspirin users; P < 0.05). In long-term, open-label trials, seven of 310 potential events were adjudicated to be ulcer complications; the annualized incidence for valdecoxib was 0.39% (seven of 1791 patient-years) for all patients and 0.2% (three of 1472 patient-years) for non-aspirin users.

CONCLUSIONS

Valdecoxib, including above recommended doses, is associated with a significantly lower rate of upper gastrointestinal ulcer complications than therapeutic doses of non-selective non-steroidal anti-inflammatory drugs.

A comparison of the upper gastrointestinal mucosal effects of valdecoxib, naproxen and placebo in healthy elderly subjects

BACKGROUND

In long-term outcomes studies, cyclooxygenase COX-2 specific inhibitors spare COX-1 at supratherapeutic doses and therefore demonstrate improved gastrointestinal safety over nonspecific nonsteroidal anti-inflammatory drugs (NSAIDs). However, in clinical practice, anti-inflammatory drugs are often used for short-term treatment of pain.

AIM

To compare the short-term upper gastrointestinal mucosal effects of naproxen with the new COX-2 specific inhibitor, valdecoxib, or placebo, in elderly subjects.

METHODS

In this multicentre, double-blind, randomized, study, elderly subjects (65-76 years old), with a normal baseline esophagogastroduodenoscopy (EGD), received oral valdecoxib (a supratherapeutic 40 mg b.d. dosage, n = 62), naproxen (500 mg b.d., n = 62), or placebo (n = 62) for 6.5 days. Upper gastrointestinal mucosal injury was evaluated post-treatment by EGD (day 7).

RESULTS

Subjects receiving naproxen (11/60, 18%) had significantly more gastroduodenal ulcers post-treatment than those receiving placebo (2/61, 3%; P < 0.01) or valdecoxib (0/60, 0%; P < 0.001). A similar significant finding was observed for gastric ulcer rates. All treatments had similar adverse event rates and clinical laboratory findings.

CONCLUSIONS

Valdecoxib, even at supratherapeutic doses, was associated with an ulcer rate significantly lower than naproxen but similar to placebo in healthy elderly subjects, despite the short duration of therapy (6.5 days). Naproxen and valdecoxib were as well tolerated as placebo.

The COX-2 selective inhibitor, valdecoxib, does not impair platelet function in the elderly: results of a randomized controlled trial

The effects of the new cyclooxygenase (COX)-2 selective inhibitor, valdecoxib (40 mg bid; n = 17), on platelet function were evaluated, along with ibuprofen (800 mg tid; n = 15) and placebo (n = 15), in healthy elderly subjects (65-85 years) in this 7.5-day, randomized, single-center, double-blind study. Platelet aggregation (to sodium arachidonate, collagen, and adenosine diphosphate), bleeding time, and serum thromboxane B2 (TxB2) concentrations were measured up to 8 hours postdose on Days 1 and 8. Valdecoxib had no platelet effects, while ibuprofen significantly decreased platelet aggregation, significantly increased bleeding time (2-4 h postdose on each day), and significantly decreased TxB2 levels at all time points. In conclusion, unlike ibuprofen, valdecoxib 40 mg bid spares platelet COX-1 function in healthy elderly subjects. Valdecoxib's lack of effect on platelet aggregation and bleeding time suggests that it will have an improved clinical profile over nonselective NSAIDs, particularly in patients for whom bleeding complications are a concern.

Incidence of gastroduodenal ulcers associated with valdecoxib compared with that of ibuprofen and diclofenac in patients with osteoarthritis

OBJECTIVE

To determine whether valdecoxib, at chronic arthritis doses, has the characteristics of a cyclo-oxygenase 2 (COX-2) specific inhibitor, as measured by a reduced incidence of upper-gastrointestinal ulceration compared with conventional nonsteroidal anti-inflammatory drugs (NSAIDs).

METHODS

This double-blind, multicentre, placebo-controlled, parallel-group study compared the incidence of gastroduodenal ulcers associated with valdecoxib 10 mg daily (q.d.) and 20 mg q.d. with that of ibuprofen 800 mg three times daily (t.i.d.) or diclofenac 75 mg twice daily (b.i.d.) when administered over a 12-week period. The incidence of gastroduodenal ulcers was assessed by upper-gastrointestinal endoscopy, performed at baseline and again at the end of week 12 (or at early study termination). Efficacy assessments were performed at baseline and at weeks 2, 6 and 12 using Patient's and Physician's Global Assessments of Arthritis.

RESULTS

A total of 1052 osteoarthritis patients were enrolled into the trial. The incidence of gastroduodenal ulcers over 12 weeks was 5% in patients receiving valdecoxib 10 mg q.d., 4% in patients receiving valdecoxib 20 mg q.d., 7% in patients receiving placebo, 16% in patients receiving ibuprofen 800 mg t.i.d. (P <0.05 v. placebo), and 17% in patients receiving diclofenac 75 mg b.i.d. (P <0.05 v. placebo). The incidence of gastroduodenal ulcers at week 12 seen in the ibuprofen 800 mg t.i.d. and diclofenac 75 mg b.i.d. groups was significantly higher than that in the valdecoxib 10 mg q.d. and valdecoxib 20 mg q.d. groups (P <0.05). The incidence rates of gastroduodenal ulcers were not significantly different between the valdecoxib treatment groups or between valdecoxib- and placebo-treated patients. Efficacy responses to valdecoxib 10 mg and 20 mg q.d. were significantly greater than placebo and comparable with both ibuprofen 800 mg t.i.d. and diclofenac 75 mg b.i.d.

CONCLUSIONS

The results of the study demonstrate that valdecoxib has an upper-gastrointestinal safety profile typical of a COX-2 specific inhibitor. Overall, the data indicate that administration of valdecoxib offers similar efficacy for the treatment of osteoarthritis but improved upper-gastrointestinal safety compared with the conventional NSAIDs, ibuprofen and diclofenac, based on the significantly lower incidence of gastroduodenal ulcers detected by endoscopy.

Valdecoxib does not impair platelet function

The platelet effects of a supratherapeutic dose of the new cyclooxygenase (COX)-2 specific inhibitor, valdecoxib (40 mg twice a day), naproxen 500 mg twice a day, diclofenac 75 mg twice a day, and placebo were compared in 62 healthy adult subjects in this 7(1/2) day single-center, randomized, placebo-controlled trial. Platelet aggregation responses (to arachidonate [AA], collagen, and adenosine diphosphate [ADP]), bleeding time, and serum thromboxane B(2) (TxB(2)) concentrations were measured at baseline and at regular intervals on days 1 and 8. Valdecoxib had no effect on platelet function. Naproxen and diclofenac significantly reduced the platelet aggregation response to AA and to a lesser extent collagen and ADP at most assessments compared with placebo. Naproxen significantly lowered serum TxB(2) levels. In contrast to standard doses of 2 nonsteroidal antiinflammatory drugs (NSAIDs), a supratherapeutic valdecoxib dosage does not impair platelet function (COX-1). Valdecoxib may be a safer analgesic option than conventional NSAIDs in patients for whom bleeding complications are a concern. (Am J Emerg Med 2002;20:275-281.

Gastrointestinal toxicity with celecoxib vs nonsteroidal anti-inflammatory drugs for osteoarthritis and rheumatoid arthritis: the CLASS study: A randomized controlled trial. Celecoxib Long-term Arthritis Safety Study

CONTEXT

Conventional nonsteroidal anti-inflammatory drugs (NSAIDs) are associated with a spectrum of toxic effects, notably gastrointestinal (GI) effects, because of inhibition of cyclooxygenase (COX)-1. Whether COX-2-specific inhibitors are associated with fewer clinical GI toxic effects is unknown.

OBJECTIVE

To determine whether celecoxib, a COX-2-specific inhibitor, is associated with a lower incidence of significant upper GI toxic effects and other adverse effects compared with conventional NSAIDs.

DESIGN

The Celecoxib Long-term Arthritis Safety Study (CLASS), a double-blind, randomized controlled trial conducted from September 1998 to March 2000.

SETTING

Three hundred eighty-six clinical sites in the United States and Canada.

PARTICIPANTS

A total of 8059 patients (>/=18 years old) with osteoarthritis (OA) or rheumatoid arthritis (RA) were enrolled in the study, and 7968 received at least 1 dose of study drug. A total of 4573 patients (57%) received treatment for 6 months.

INTERVENTIONS

Patients were randomly assigned to receive celecoxib, 400 mg twice per day (2 and 4 times the maximum RA and OA dosages, respectively; n = 3987); ibuprofen, 800 mg 3 times per day (n = 1985); or diclofenac, 75 mg twice per day (n = 1996). Aspirin use for cardiovascular prophylaxis (</=325 mg/d) was permitted.

MAIN OUTCOME MEASURES

Incidence of prospectively defined symptomatic upper GI ulcers and ulcer complications (bleeding, perforation, and obstruction) and other adverse effects during the 6-month treatment period.

RESULTS

For all patients, the annualized incidence rates of upper GI ulcer complications alone and combined with symptomatic ulcers for celecoxib vs NSAIDs were 0.76% vs 1.45% (P =.09) and 2. 08% vs 3.54% (P =.02), respectively. For patients not taking aspirin, the annualized incidence rates of upper GI ulcer complications alone and combined with symptomatic ulcers for celecoxib vs NSAIDs were 0.44% vs 1.27% (P =.04) and 1.40% vs 2.91% (P =.02). For patients taking aspirin, the annualized incidence rates of upper GI ulcer complications alone and combined with symptomatic ulcers for celecoxib vs NSAIDs were 2.01% vs 2.12% (P =.92) and 4.70% vs 6.00% (P =.49). Fewer celecoxib-treated patients than NSAID-treated patients experienced chronic GI blood loss, GI intolerance, hepatotoxicity, or renal toxicity. No difference was noted in the incidence of cardiovascular events between celecoxib and NSAIDs, irrespective of aspirin use.

CONCLUSIONS

In this study, celecoxib, at dosages greater than those indicated clinically, was associated with a lower incidence of symptomatic ulcers and ulcer complications combined, as well as other clinically important toxic effects, compared with NSAIDs at standard dosages. The decrease in upper GI toxicity was strongest among patients not taking aspirin concomitantly. JAMA. 2000;284:1247-1255

Protein expression, vascular reactivity and soluble guanylate cyclase activity in mice lacking the endothelial cell nitric oxide synthase: contributions of NOS isoforms to blood pressure and heart rate control

OBJECTIVE

Both disruption of the endothelial nitric oxide synthase (eNOS) gene and pharmacological inhibition of the NOS produce modest hypertension. It is unclear if and to what extent NOS isoforms other than eNOS contribute to this effect and how loss of one copy of the eNOS gene might impact on vascular reactivity or eNOS protein expression.

METHODS

We examined protein expression, vascular reactivity, activity of soluble guanylate cyclase, blood pressure and heart rate in mice completely lacking the eNOS gene (eNOS-/-), wild-type mice (eNOS+/+) and mice heterozygotic for the eNOS gene (eNOS+/-).

RESULTS

While eNOS-/- mice had mild hypertension and bradycardia, eNOS+/- mice were normotensive. In control mice, oral administration of L-NAME (approximately 100 mg/kg/day x 21 days) increased blood pressure to levels observed in eNOS-/- mice. In eNOS-/- mice, chronic oral administration of L-NAME had no effect on blood pressure, suggesting that inhibition of other NOS isoforms unlikely contribute to hypertension. L-NAME treatment induced bradycardia in both control and eNOS-/- mice, suggesting that both eNOS and other isoforms of NOS might be involved in heart rate control. Studies of aortic rings from eNOS-/- mice revealed a complete lack of endothelium-dependent vascular relaxation in response to acetylcholine and the calcium ionophore A23187 and an increase in sensitivity to phenylephrine, serotonin and nitroglycerin. Aortic rings from eNOS+/- mice demonstrated only minor alterations of responses to nitroglycerin and a normal relaxation to either acetylcholine or A23187 compared to vessels from eNOS-/+. Western analysis demonstrated that eNOS expression was virtually identical between eNOS+/+ and eNOS+/- mice and was absent in eNOS-/- mice. The activity of lung-isolated soluble guanylate cyclase was identical in the three strains of mice.

CONCLUSIONS

We conclude that loss of one copy of the eNOS gene, as observed in heterozygotic animals, has no effect on vascular reactivity, blood pressure or eNOS protein expression. Isoforms of NOS, other than eNOS are unlikely involved in blood pressure regulation but may participate in heart rate control.

Inducible nitric oxide synthase (iNOS) in the human heart: expression and localization in congestive heart failure

The inducible nitric oxide (NO) synthase (iNOS or NOS2) generates a prolonged release of large amounts of NO which may be cytotoxic and/or inhibit myocyte contractility. It has been suggested that this mechanism specifically contributes to heart failure caused by dilated cardiomyopathy (DCM). To test this hypothesis we compared the myocardial amount and localization of iNOS in myocardial biopsies from patients with heart failure caused by either DCM or ischemic heart disease (IHD). During heart transplantation, myocardial biopsies collected from the diseased heart after explantation were frozen in liquid nitrogen. Twenty-two patients in NYHA class III-IV were included (DCM: n = 8; IHD: n = 14). In each biopsy, iNOS expression was assessed using reverse transcription polymerase chain reaction (RT-PCR), and visualized by immunohistochemistry. iNOS was detected in all biopsies. Intriguingly, the amount of iNOS mRNA (shown as iNOS cDNA normalized to GADPH cDNA) did not differ significantly between the two groups (DCM 30 +/- 7; IHD 20 +/- 6, mean +/- S.E.M., P > 0.05). Similarly, no inter-group differences in the amount of iNOS protein (Western) were observed. iNOS was invariably located to vascular endothelial and smooth muscle cells. In addition, an iNOS reaction in relation to the myocyte membrane was found in 4 of the 22 patients. These four patients (two from each group) had significantly (P < 0.05) higher iNOS/GADPH ratios (54 +/- 20) than patients without myocyte membrane iNOS reaction (17 +/- 15). In conclusion, iNOS is expressed in the myocardium of all patients with heart failure caused by either DCM or IHD. iNOS is located primarily and invariably in the endothelium and vascular smooth muscle cells of the myocardial vasculature and its expression appears to be associated with the condition of heart failure per se rather than related to the heart failure etiology.

Identification and regulation of protein kinase C-delta in human neutrophils

The intracellular mechanisms that regulate the function of human neutrophils are not well understood. Receptor-initiated signaling events result in the production of several second messengers (e.g., Ca2+, diacylglycerol, phosphatidic acid, and arachidonic acid) with the potential to activate members of the protein kinase C (PKC) family of signaling enzymes. The mixture of second messenger signaling molecules produced usually varies, depending on the particular receptor engaged. Previous work suggests that PKC has complex regulatory effects on neutrophil function. This may be due to the presence of multiple isoforms of the enzyme family, responding differentially to the second messengers produced. In studies to identify the PKC isoforms present in human neutrophils, we discovered the presence of the PKC isoform delta in these cells. Like other previously identified isoforms (alpha, beta I, beta II, and zeta), delta is a cytosolic enzyme in unstimulated neutrophils and partially translocates to membrane-containing fractions in cells stimulated by either the PKC activator PMA or the chemoattractant FMLP. Partial purification of cytosolic PKC gave two peaks of activity. The beta isoforms predominated in peak I, while the delta isoform predominated in peak II. The identification of delta indicates that neutrophils contain at least one member of the Ca(2+)-independent, diacylglycerol-dependent subfamily of PKC isoforms. Thus, this isoform may participate in Ca(2+)-independent, but diacylglycerol-dependent signaling events in these cells.

Identification and regulation of protein kinase C-delta in human neutrophils

The intracellular mechanisms that regulate the function of human neutrophils are not well understood. Receptor-initiated signaling events result in the production of several second messengers (e.g., Ca2+, diacylglycerol, phosphatidic acid, and arachidonic acid) with the potential to activate members of the protein kinase C (PKC) family of signaling enzymes. The mixture of second messenger signaling molecules produced usually varies, depending on the particular receptor engaged. Previous work suggests that PKC has complex regulatory effects on neutrophil function. This may be due to the presence of multiple isoforms of the enzyme family, responding differentially to the second messengers produced. In studies to identify the PKC isoforms present in human neutrophils, we discovered the presence of the PKC isoform delta in these cells. Like other previously identified isoforms (alpha, beta I, beta II, and zeta), delta is a cytosolic enzyme in unstimulated neutrophils and partially translocates to membrane-containing fractions in cells stimulated by either the PKC activator PMA or the chemoattractant FMLP. Partial purification of cytosolic PKC gave two peaks of activity. The beta isoforms predominated in peak I, while the delta isoform predominated in peak II. The identification of delta indicates that neutrophils contain at least one member of the Ca(2+)-independent, diacylglycerol-dependent subfamily of PKC isoforms. Thus, this isoform may participate in Ca(2+)-independent, but diacylglycerol-dependent signaling events in these cells.

Identification, characterization, and comparison of the calmodulin-binding domains of the endothelial and inducible nitric oxide synthases

The calmodulin (CaM)-binding regions in bovine endothelial nitric oxide synthase (eNOS) and murine inducible nitric oxide synthase (iNOS) are identified in this study as eNOS residues 493-512 and iNOS residues 501-532. Peptides corresponding to eNOS 493-512 and NOS 501-532 produce a (Ca2+)-dependent, electrophoretic mobility shift of CaM on 4 M urea gels. The two peptides are also potent inhibitors of the CaM-mediated activation of neuronal nitric oxide synthase and have dissociation constants for CaM binding of 4.0 and 1.5 nM respectively. Substitution of eNOS and iNOS CaM-binding domains in eNOS/iNOS chimeric proteins produces major alterations in the Ca2+ and CaM dependence of the intact enzymes expressed and purified from a baculovirus/Sf9 insect cell system. Replacement of aligned NOS sequence with eNOS 493-512 creates a functional, chimeric iNOS that is both (Ca2+)- and CaM-dependent. Replacement of aligned eNOS sequence with NOS 501-532 creates a functional, chimeric eNOS that is CaM-independent but that remains (Ca2+)-dependent. Specific amino acid residues critical for CaM binding by eNOS are also identified in this study as Phe-498, Lys-499, and Leu-511 in the bovine eNOS sequence.

Effects of Late-Afternoon Methylphenidate Administration on Behavior and Sleep in Attention-Deficit Hyperactivity Disorder

Objective. This study evaluated the effects on behavior and sleep of methylphenidate (MPH) administered at 4 PM to children with attention-deficit hyperactivity disorder (ADHD).

Methodology. Twelve children admitted to a child psychiatric inpatient service with ADHD participated in a double-blind, crossover study in which they received a 4 PM dose of either 15 mg of MPH, 10 mg of MPH, or a placebo in random order for 12 consecutive days. Ratings of behavior, including ADHD symptoms, pertaining to the period from dose administration until sleep onset, were supplied nightly by hospital staff. Sleep latency and sleep adequacy were also assessed for each night.

Results. MPH resulted in markedly improved behavioral control compared with placebo; there was no difference between 15-mg and 10-mg MPH doses. MPH did not alter sleep latencies observed with the placebo. Children were more often rated as less tired on awakening after nights that they received 10 mg of MPH compared with 15 mg of MPH and the placebo. Weight loss was apparent among 83% of the patients, but dinner intake did not vary with third-dose condition.

Conclusions. Morning and noon administration of stimulants to children with ADHD is a near-universal practice, but many clinicians avoid a third, late-afternoon administration for fear of inducing insomnia. This study's findings show that children with ADHD derive substantial symptom reduction from MPH administered in late afternoon, with no untoward effects on sleep. Therefore, three-times-a-day dosing should be considered for those children exhibiting ADHD symptoms in the evening. Adverse effects on sleep latency were not apparent in the sample overall. Nonetheless, monitoring for possible aggravation of sleep problems and weight loss remains sound treatment practice.

Munchausen's syndrome and substance abuse

The syndrome of factitious disorders with physical symptoms was named "Munchausen's syndrome" by Richard Asher (1951). The present article contains an interesting case report of a patient who has a history of Munchausen's syndrome, substance abuse, and genuine physical illness. A review of the literature supports a strong association of substance abuse in patients with Munchausen's syndrome. Also important for clinicians to remember is that patients with Munchausen's syndrome often have true physical illnesses which need appropriate treatment. The patient described here has successfully begun treatment with methadone maintenance, but further study will be needed regarding methadone maintenance's role in the management of Munchausen's syndrome.

Propranolol, a phosphatidate phosphohydrolase inhibitor, also inhibits protein kinase C

Propranolol, a beta-adrenergic receptor antagonist, also inhibits phosphatidate phosphohydrolase, the enzyme that converts phosphatidic acid into diacylglycerol. This latter effect has prompted recent use of propranolol in studies examining the importance of diacylglycerol and phosphatidic acid in cellular signalling events. Here, we show that propranolol is also an inhibitor of protein kinase C. At concentrations greater than or equal to 20 microM, propranolol reduced [3H]phorbol dibutyrate binding (IC50 = 200 microM) and phorbol myristate acetate-stimulated superoxide anion release (IC50 = 130 microM) in human neutrophils. Scatchard analysis showed that propranolol lowers the number of phorbol diester binding sites without significantly affecting their affinity. In vitro kinetic analysis, performed in a mixed micellar assay with protein kinase C purified from human neutrophils, suggested a competitive inhibition of propranolol with the cofactor phosphatidylserine. Complex kinetic patterns were observed with respect to diacylglycerol and ATP, approximating competitive and noncompetitive inhibition, respectively. Taken together, these results suggest that the drug interacts at the level of the regulatory domain of the enzyme. Fifty % inhibition occurred at approximately 150 microM propranolol. Similar levels of inhibition were obtained using exogenous (histone) and endogenous (p47-phox, a NADPH oxidase component) substrates. Protein kinase C-alpha and protein kinase C-beta, two protein kinase C isozymes present in human neutrophils, were inhibited by propranolol in a comparable manner. In the range of concentrations tested (30-1000 microM), neither cAMP-dependent protein kinase nor neutrophil protein tyrosine kinases were affected. The racemic form of propranolol and the (+) and the (-) stereoisomers were equally active, and other beta-adrenergic receptor antagonists (pindolol) and agonists (isoproterenol) were inactive. This suggests that the inhibitory action of propranolol on protein kinase C is related to the amphipathic nature of the drug rather than to its beta-adrenergic receptor blocking ability. Analogs of propranolol were synthesized and found to be more potent protein kinase C inhibitors, with IC50 values in the 10-20 microM range. We conclude that the ability of propranolol to inhibit both protein kinase C and PA phosphohydrolase complicates interpretation of results when this drug is used in signal transduction studies. In addition, propranolol may be a useful prototype for the synthesis of new protein kinase C inhibitors.

Effect of diabetes and insulin treatment of diabetic rats on total RNA, poly(A)+ RNA, and mRNA in skeletal muscle

We have assessed the time course of alterations in several biochemical parameters and expression of specific mRNAs in gastrocnemius muscle following both the induction of diabetes and the administration of insulin to diabetic rats. Muscle mass, total RNA, and total protein were reduced, whereas poly(A)+ RNA relative to total RNA was increased following the induction of diabetes. All the above parameters, with the exception of poly(A)+ RNA, were reciprocally and rapidly altered following administration of insulin to 3-day diabetic animals. These changes suggest that during the induction of diabetes 1) total cellular protein is reduced at a rate that is less than the reduction in gastrocnemius mass, whereas RNA is reduced at a rate 1.5 times the reduction in tissue mass, and 2) poly(A)+ RNA is elevated relative to total RNA. After insulin administration, there appears to be coordinate synthesis of both poly(A)+ RNA and ribosomal RNA, assuming 85% of total RNA is ribosomal. Therefore, we conclude that poly(A)+ RNA is more stable than ribosomal RNA during diabetes, whereas the amounts of poly(A)+ RNA and ribosomal RNA are increased at the same rates following insulin administration to diabetic animals. Analysis of expression of specific gene products over the same time course, as assessed by in vitro translation of total RNA followed by two-dimensional gel analysis, suggests that there are a few mRNAs that are very rapidly altered in response to insulin administration. The mRNAs that are altered demonstrate variable temporal patterns of either repression or full or transient expression. These rapid, but limited, alterations in gene expression may prove important in the development of the defects that occur in skeletal muscle in response to diabetes.

An assessment of the validity of densitometric measures of striatal tyrosine hydroxylase-positive fibers: relationship to apomorphine-induced rotations in 6-hydroxydopamine lesioned rats

The power of immunohistochemical staining as a tool for the study of the neurochemical anatomy of the brain would be greatly enhanced if quantitative measures of staining were to be developed. We have here assessed the reliability and validity of two population measures of extent of fiber innervation: percent area occupied by staining, and average optical density (AOD) of staining. We have evaluated these measures for tyrosine hydroxylase-positive staining of the striatum in relation to apomorphine-induced rotational behavior in 6-hydroxydopamine lesioned rats. We have found that inter-operator reliability for the area measure is high (r = 0.98). Apomorphine-induced rotations were observed when the area measured was reduced to 2% or less of the control side, and when the density measure was reduced to 15% or less. These results are similar to those obtained previously for biochemical assay of TH activity, which showed rotations at reductions to 10% or less. We conclude that these density measures provide valid relative indices of extent of fiber innervation on the same section. The AOD measure appears to be more sensitive at lower levels of innervation.

Effects of experimentally induced nephrosis on protein synthesis in rat liver

A nephrotic syndrome was experimentally induced in rats by a single intravenous injection of aminonucleoside of puromycin. Experimental animals were studied 8 days after the injection, at which time they exhibited marked proteinuria and hypoalbuminemia compared with control animals. The experimental animals also exhibited alterations in protein synthesis in liver as evidenced by a marked increase in the rate of albumin synthesis relative to total hepatic protein synthesis, changes in the relative concentrations of several plasma proteins, an increased protein content of plasma, an increased liver weight relative to body weight, and an increased RNA content of liver. Perfused liver preparations derived from nephrotic rats exhibited an increased release of albumin and other secretory proteins compared with control preparations. In contrast, there was no difference in the rate of synthesis of nonexported proteins between the two groups. The elevation in the relative rate of albumin synthesis was accompanied by a relative increase of the same magnitude in albumin mRNA. Furthermore, the relative amounts of several other mRNAs, including those coding for beta-fibrinogen, haptoglobin, metallothionein II, and two unidentified proteins, were increased, whereas the amount of mRNA coding for alpha 1-acid glycoprotein was decreased in livers of nephrotic rats compared to controls. These results indicate that nephrosis leads to marked alterations in the synthesis of albumin and other plasma proteins. Mechanisms responsible for these alterations include changes in the relative abundance of specific mRNAs and an increase in total cellular RNA.