Effects of Febuxostat in Early Gout: A Randomized, Double-Blind, Placebo-Controlled Study

Objective

To assess the effect of treatment with febuxostat versus placebo on joint damage in hyperuricemic subjects with early gout (1 or 2 gout flares).

Methods

In this double‐blind, placebo‐controlled study, 314 subjects with hyperuricemia (serum uric acid [UA] level of ≥7.0 mg/dl) and early gout were randomized 1:1 to receive once‐daily febuxostat 40 mg (increased to 80 mg if the serum UA level was ≥6.0 mg/dl on day 14) or placebo. The primary efficacy end point was the mean change from baseline to month 24 in the modified Sharp/van der Heijde erosion score for the single affected joint. Additional efficacy end points included change from baseline to month 24 in the Rheumatoid Arthritis Magnetic Resonance Imaging Scoring (RAMRIS) scores for synovitis, erosion, and edema in the single affected joint, the incidence of gout flares, and serum UA levels. Safety was assessed throughout the study.

Results

Treatment with febuxostat did not lead to any notable changes in joint erosion over 2 years. In both treatment groups, the mean change from baseline to month 24 in the modified Sharp/van der Heijde erosion score for the single affected joint was minimal, with no between‐group differences. However, treatment with febuxostat significantly improved the RAMRIS synovitis score at month 24 compared with placebo treatment (change from baseline −0.43 versus −0.07; P <0.001), decreased the overall incidence of gout flares (29.3% versus 41.4%; P < 0.05), and improved serum UA control (62.8% versus 5.7%; P < 0.001). No major safety concerns were reported.

Conclusion

Urate‐lowering therapy with febuxostat improved magnetic resonance imaging–determined synovitis and reduced the incidence of gout flares in subjects with early gout.

Diabetes and gout: efficacy and safety of febuxostat and allopurinol

AIM

Assess influences of demographics and co-morbidities of gout patients with or without diabetes on safety and efficacy of urate-lowering agents.

METHODS

Post-hoc analysis of 312 diabetic and 1957 non-diabetic gout patients [baseline serum urate levels (sUA) ≥8.0 mg/dl] enrolled in a 6-month randomized controlled trial comparing urate-lowering efficacy (ULE) and safety of daily xanthine oxidase inhibitors (XOIs) febuxostat (40 mg or 80 mg) and allopurinol (200 mg or 300 mg). We compared baseline demographic, gout and co-morbid characteristics, ULE, and safety of XOI treatment in diabetic and non-diabetic gout patients. ULE was measured by the proportion of diabetic and non-diabetic patients in each treatment group achieving final visit sUA < 6.0 mg/dl. Safety was monitored throughout the trial.

RESULTS

Diabetic gout patients were older, more frequently female, and had longer gout duration. Co-morbidities were more frequent among diabetic patients: cardiovascular disease; impaired renal function; hyperlipidemia; and obesity (body mass index >30 kg/m²) (p < 0.001 for all comparisons). Febuxostat 80 mg ULE exceeded that of febuxostat 40 mg or allopurinol (p < 0.050) at all levels of renal function, achieving sUA goal range in the majority of diabetic and non-diabetic patients. Diabetics and non-diabetics reported self-limiting diarrhoea and URIs as the most common adverse events.

CONCLUSIONS

Despite higher co-morbidity rates in diabetic patients, febuxostat and allopurinol were safe in both groups at the doses tested. Febuxostat 80 mg achieved sUA <6.0 mg/dl more often than febuxostat 40 mg or allopurinol at commonly prescribed doses.

Randomized controlled trial of febuxostat versus allopurinol or placebo in individuals with higher urinary uric acid excretion and calcium stones

BACKGROUND AND OBJECTIVES

Higher urinary uric acid excretion is a suspected risk factor for calcium oxalate stone formation. Febuxostat, a xanthine oxidoreductase inhibitor, is effective in lowering serum urate concentration and urinary uric acid excretion in healthy volunteers and people with gout. This work studied whether febuxostat, compared with allopurinol and placebo, would reduce 24-hour urinary uric acid excretion and prevent stone growth or new stone formation.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

In this 6-month, double-blind, multicenter, randomized controlled trial, hyperuricosuric participants with a recent history of calcium stones and one or more radio-opaque calcium stone ≥ 3 mm (as seen by multidetector computed tomography) received daily febuxostat at 80 mg, allopurinol at 300 mg, or placebo. The primary end point was percent change from baseline to month 6 in 24-hour urinary uric acid. Secondary end points included percent change from baseline to month 6 in size of index stone and change from baseline in the mean number of stones and 24-hour creatinine clearance.

RESULTS

Of 99 enrolled participants, 86 participants completed the study. Febuxostat led to significantly greater reduction in 24-hour urinary uric acid (-58.6%) than either allopurinol (-36.4%; P=0.003) or placebo (-12.7%; P<0.001). Percent change from baseline in the size of the largest calcium stone was not different with febuxostat compared with allopurinol or placebo. There was no change in stone size, stone number, or renal function. No new safety concerns were noted for either drug.

CONCLUSIONS

Febuxostat (80 mg) lowered 24-hour urinary uric acid significantly more than allopurinol (300 mg) in stone formers with higher urinary uric acid excretion after 6 months of treatment. There was no change in stone size or number over the 6-month period.

Treating hyperuricemia of gout: safety and efficacy of febuxostat and allopurinol in older versus younger subjects

Despite an increasing incidence of gout in older age patients with multiple metabolic and cardiovascular comorbidities, there are limited data addressing whether currently available urate-lowering therapy is comparably effective and safe in older (≥65 years of age) versus younger (<65 years of age) patients. In this secondary analysis of data from the CONFIRMS trial, we found that among 374 older subjects, urate-lowering therapy with approved doses of febuxostat or commonly prescribed doses of allopurinol was at least comparable to that in 1894 younger subjects and was well tolerated despite high rates of renal impairment and cardiovascular comorbidities in the older subjects.

Women with gout: efficacy and safety of urate-lowering with febuxostat and allopurinol

OBJECTIVE

To compare the characteristics of female versus male gout patients and assess urate-lowering efficacy and safety of febuxostat or allopurinol treatment in women with gout.

METHODS

This was a retrospective analysis of 4,101 hyperuricemic (serum urate [sUA] level ≥8.0 mg/dl) gout subjects enrolled in 3 phase III comparative trials and randomized to receive placebo, febuxostat (40 mg, 80 mg, 120 mg, or 240 mg daily), or allopurinol (100 mg, 200 mg, or 300 mg daily, based on renal function). Baseline demographics and characteristics were summarized and compared between female and male subjects. Urate-lowering efficacy, which was defined as the proportion of subjects with sUA levels <6.0 mg/dl at final visit, was assessed for all subjects and, among women, according to baseline renal function.

RESULTS

Female gout subjects (n = 226) were older with significantly higher rates of obesity and metabolic and cardiovascular comorbidities than their male counterparts. The percentage of female subjects with sUA levels <6.0 mg/dl at final visit was 0% in the placebo group, 54.3%, 85.1%, 81.0%, and 100.0% in the febuxostat 40 mg, 80 mg, 120 mg, and 240 mg groups, respectively, and 45.9% in the allopurinol group. Similar patterns of urate-lowering efficacy rates were observed when stratified by renal function. Among all the female subjects, febuxostat 80 mg was significantly more efficacious than allopurinol (P < 0.001). Rates of adverse events (AEs) were low. The most frequently reported AEs were upper respiratory tract infections, musculoskeletal/connective tissue disorders, and diarrhea.

CONCLUSION

These data suggest that febuxostat 80 mg may be more efficacious than commonly prescribed doses of allopurinol in female gout subjects with high rates of comorbidities.

African American patients with gout: efficacy and safety of febuxostat vs allopurinol

BACKGROUND

African Americans are twice as likely as Caucasians to develop gout, but they are less likely to be treated with urate-lowering therapy (ULT). Furthermore, African Americans typically present with more comorbidities associated with gout, such as hypertension, obesity, and renal impairment. We determined the efficacy and safety of ULT with febuxostat or allopurinol in African American subjects with gout and associated comorbidities and in comparison to Caucasian gout subjects.

METHODS

This is a secondary analysis of the 6-month Phase 3 CONFIRMS trial. Eligible gouty subjects with baseline serum urate (sUA) ≥ 8.0 mg/dL were randomized 1:1:1 to receive febuxostat 40 mg, febuxostat 80 mg, or allopurinol (300 mg or 200 mg depending on renal function) daily. All subjects received gout flare prophylaxis. Primary efficacy endpoint was the proportion of subjects in each treatment group with sUA < 6.0 mg/dL at the final visit. Additional endpoints included the proportion of subjects with mild or with moderate renal impairment who achieved a target sUA < 6.0 mg/dL at final visit. Adverse events (AEs) were recorded throughout the study.

RESULTS

Of the 2,269 subjects enrolled, 10.0% were African American and 82.1% were Caucasian. African American subjects were mostly male (89.5%), obese (BMI ≥ 30 kg/m2; 67.1%), with mean baseline sUA of 9.8 mg/dL and mean duration of gout of 10.4 years. The proportions of African American subjects with a baseline history of diabetes, renal impairment, or cardiovascular disease were significantly higher compared to Caucasians (p < 0.001). ULT with febuxostat 80 mg was superior to both febuxostat 40 mg (p < 0.001) and allopurinol (p = 0.004). Febuxostat 40 mg was comparable in efficacy to allopurinol. Significantly more African American subjects with mild or moderate renal impairment achieved sUA < 6.0 mg/dL in the febuxostat 80 group than in either the febuxostat 40 mg or allopurinol group (p < 0.05). Efficacy rates in all treatment groups regardless of renal function were comparable between African American and Caucasian subjects, as were AE rates.

CONCLUSIONS

In African American subjects with significant comorbidities, febuxostat 80 mg is significantly more efficacious than either febuxostat 40 mg or allopurinol 200/300 mg. Febuxostat was well tolerated in this African American population.Please see related article: http://www.biomedcentral.com/1741-7015/10/15.

Serum urate in chronic gout--will it be the first validated soluble biomarker in rheumatology?

OBJECTIVE

To summarize evidence for and endorsement of serum urate (SU) as having fulfilled the OMERACT filter as a soluble biomarker in chronic gout at the 2010 Outcome Measures in Rheumatology Meeting (OMERACT 10).

METHODS

Data were presented to support the use of SU as a soluble biomarker in chronic gout and specifically the ability to utilize it to predict future patient-reported outcomes.

RESULTS

SU was accepted as having fulfilled the OMERACT filter by 78% of voters. However, consensus was not obtained regarding its use as a soluble biomarker in chronic gout. Although the majority of the criteria for a soluble biomarker were fulfilled, the key criterion of association of the biomarker with outcomes was not agreed upon. It was agreed that the appropriate choice of endpoint must be linked to its clinical importance to the individual with the disorder and its temporal relationship to the intervention. Appropriate outcomes in chronic gout may therefore include gout flares, reduction in tophi, and patient-reported outcomes.

CONCLUSION

SU is a critical outcome measure. It has the potential to fulfil criteria for a soluble biomarker. Further analyses of existing data from randomized controlled trials will be required to determine whether SU can predict future important outcomes, in particular disability.

Bringing it all together: a novel approach to the development of response criteria for chronic gout clinical trials

OBJECTIVE

To review a novel approach for constructing composite response criteria for use in chronic gout clinical trials that implements a method of multicriteria decision-making.

METHODS

Preliminary work with paper patient profiles led to a restricted set of core-set domains that were examined using 1000Minds™ by rheumatologists with an interest in gout, and (separately) by OMERACT registrants prior to OMERACT 10. These results and the 1000Minds approach were discussed during OMERACT 10 to help guide next steps in developing composite response criteria.

RESULTS

There were differences in how individual indicators of response were weighted between gout experts and OMERACT registrants. Gout experts placed more weight upon changes in uric acid levels, whereas OMERACT registrants placed more weight upon reducing flares. Discussion highlighted the need for a "pain" domain to be included, for "worsening" to be an additional level within each indicator, for a group process to determine the decision-making within a 1000Minds exercise, and for the value of patient involvement.

CONCLUSION

Although there was not unanimous support for the 1000Minds approach to inform the construction of composite response criteria, there is sufficient interest to justify ongoing development of this methodology and its application to real clinical trial data.

Tophus measurement as an outcome measure for clinical trials of chronic gout: progress and research priorities

Despite the recognition that tophus regression is an important outcome measure in clinical trials of chronic gout, there is no agreed upon method of tophus measurement. A number of methods have been used in clinical trials of chronic gout, from simple physical measurement techniques to more complex advanced imaging methods. This article summarizes methods of tophus measurement and discusses their properties. Physical measurement using Vernier calipers meets most aspects of the Outcome Measures in Rheumatology (OMERACT) filter. Rigorous testing of the complex methods, particularly with respect to reliability and sensitivity to change, is needed to determine the appropriate use of these methods. Further information is also required regarding which method of physical measurement is best for use in future clinical trials. The need to develop and test a patient-reported outcome measure of tophus burden is also highlighted.

Patient-reported outcomes in chronic gout: a report from OMERACT 10

OBJECTIVE

To summarize the endorsement of measures of patient-reported outcome (PRO) domains in chronic gout at the 2010 Outcome Measures in Rheumatology Meeting (OMERACT 10).

METHODS

During the OMERACT 10 gout workshop, validation data were presented for key PRO domains including pain [pain by visual analog scale (VAS)], patient global (patient global VAS), activity limitation [Health Assessment Questionnaire-Disability Index (HAQ-DI)], and a disease-specific measure, the Gout Assessment Questionnaire version 2.0 (GAQ v2.0). Data were presented on all 3 aspects of the OMERACT filters of truth, discrimination, and feasibility. One PRO, health-related quality of life measurement with the Medical Outcomes Study Short-form 36 (SF-36), was previously endorsed at OMERACT 9.

RESULTS

One measure for each of the 3 PRO of pain, patient global, and activity limitation was endorsed by > 70% of the OMERACT delegates to have appropriate validation data. Specifically, pain measurement by VAS was endorsed by 85%, patient global assessment by VAS by 73%, and activity limitation by HAQ-DI by 71%. GAQ v2.0 received 30% vote and was not endorsed due to several concerns including low internal consistency and lack of familiarity with the measure. More validation studies are needed for this measure.

CONCLUSION

With the endorsement of one measure each for pain, patient global, SF-36, and activity limitation, all 4 PRO for chronic gout have been endorsed. Future validation studies are needed for the disease-specific measure, GAQ v2.0. Validation for PRO for acute gout will be the focus of the next validation exercise for the OMERACT gout group.

Febuxostat in gout: serum urate response in uric acid overproducers and underexcretors

OBJECTIVE

Hyperuricemia of gout can arise due to either overproduction or underexcretion of uric acid. Not all available urate-lowering therapies are equally effective and safe for use in patients with renal disease. The objective of this post-hoc analysis was to determine the effectiveness of the xanthine oxidase inhibitor febuxostat in reducing serum urate (sUA) levels in gouty patients who were either overproducers or underexcretors.

METHODS

Gouty subjects 18 to 85 years of age with sUA ≥ 8.0 mg/dl at baseline were enrolled in a Phase 2, 28-day, multicenter, randomized, double-blind, placebo-controlled trial and randomized to receive febuxostat 40 mg, 80 mg, or 120 mg daily, or placebo. The primary efficacy endpoint was the proportion of subjects with sUA < 6.0 mg/dl at Day 28. Secondary efficacy endpoints included percentage reductions in sUA and urinary uric acid (uUA) from baseline to Day 28.

RESULTS

Of the 153 subjects, 118 (77%) were underexcretors (uUA ≤ 800 mg/24 h) and 32 (21%) were overproducers (uUA > 800 mg/24 h); baseline uUA data were missing for 3 subjects. Treatment with febuxostat led to the majority of subjects achieving sUA < 6.0 mg/dl at Day 28. Treatment with any dose of febuxostat led to significantly greater percentage reductions in uUA than that observed in the placebo group, for both underexcretors and overproducers.

CONCLUSION

Febuxostat is a highly efficacious urate-lowering therapy in patients with gout regardless of overproduction or underexcretion status.

Febuxostat in the treatment of gout: 5-yr findings of the FOCUS efficacy and safety study

OBJECTIVES

This 5-yr study assessed urate-lowering and clinical efficacy and safety of long-term febuxostat therapy in subjects with gout. The primary efficacy end-point was reduction to and maintenance of serum urate (sUA) levels < 6.0 mg/dl.

METHODS

Subjects who completed a previous 28-day study were entered into an open-label extension study and initially received febuxostat 80 mg daily. Between Weeks 4 and 24, dosing could be adjusted to febuxostat 40 or 120 mg. All subjects received gout flare prophylaxis during the first 4 weeks. Gout flares were recorded and treated throughout the study, and sUA, baseline tophi and safety were monitored.

RESULTS

Among 116 subjects initially enrolled, dose adjustments were made for 44 (38%) subjects. As a result, 8 subjects received febuxostat 40 mg, 79 received 80 mg, and 29 received 120 mg daily maintenance dose. At 5 yrs, 93% (54/58) of the remaining subjects had sUA < 6.0 mg/dl. Fifty-eight subjects (50%) discontinued prematurely; 38 did so in the first year. Thirteen subjects withdrew due to an adverse event. Sustained reduction of sUA was associated with nearly complete elimination of gout flares. In 26 subjects with a tophus at baseline, resolution was achieved in 69% (18/26) by last visit on study drug at any point during the study (Final Visit). There were no deaths reported during the study.

CONCLUSIONS

Long-term treatment with febuxostat resulted in durable maintenance of sUA < 6.0 mg/dl for most subjects. There was nearly complete abolition of gout flares in patients completing the study. Baseline tophi resolved in a majority of subjects.

Clinical efficacy and safety of successful longterm urate lowering with febuxostat or allopurinol in subjects with gout

OBJECTIVE

To determine longterm urate-lowering efficacy and clinical benefits and safety of therapy with febuxostat or allopurinol in subjects with gout.

METHODS

Subjects (n=1086) in this open-label extension study were assigned to fixed-dose daily urate-lowering treatment (ULT) with febuxostat (80 mg or 120 mg) or allopurinol (300 mg). ULT reassignment was permitted during months 1 to 6 to achieve serum urate (SUA) concentrations between 3.0 and <6.0 mg/dl. Flares requiring treatment, tophus size, safety, and SUA levels were monitored during up to 40 months of ULT maintenance.

RESULTS

After 1 month initial treatment, >80% of subjects receiving either febuxostat dose, but only 46% of subjects receiving allopurinol, achieved SUA<6.0 mg/dl. After ULT reassignment, >80% of all remaining subjects maintained the primary efficacy endpoint of SUA<6.0 mg/dl at each visit. More subjects initially randomized to allopurinol required ULT reassignment to achieve SUA<6.0 mg/dl compared with subjects receiving febuxostat. Maintenance of SUA<6.0 mg/dl resulted in progressive reduction to nearly 0 in proportion of subjects requiring gout flare treatment. Baseline tophus resolution was achieved by 46%, 36%, and 29% of subjects maintained on febuxostat 80 mg, febuxostat 120 mg, and allopurinol, respectively. Overall adverse event rates (including cardiovascular adverse event rates), adjusted for 10-fold greater febuxostat than allopurinol exposure, did not differ significantly among treatment groups.

CONCLUSION

Durable maintenance of goal range SUA level with either dose of febuxostat or in smaller numbers of subjects with allopurinol resulted in near elimination of gout flares and improved tophus status over time. Registered as NCT00175019.

Determinants of the clinical outcomes of gout during the first year of urate-lowering therapy

Clinical benefit early in urate-lowering treatment of gout is difficult to document. We examined data from 1,832 gouty subjects treated with either urate-lowering agents or placebo to identify determinants of gout flare incidence and tophus size during year 1 of treatment. Reductions from pretreatment serum urate levels influenced flare frequency and tophus size, but the effect of urate level on flare incidence was biphasic. Lower urate levels were associated with higher flare incidence early in treatment but lower incidence by one year. The complex relationship between urate-lowering and clinical outcome early in treatment has implications for both clinical and investigative approaches to urate-lowering management.

Magnetic resonance imaging in the quantitative assessment of gouty tophi

Measurements of tophus size can be important in monitoring the course of gout therapy, as tophus resolution is proposed as one measure of success of treatment. This multicentre study assessed the intra- and interreader reproducibility of quantitative tophus volume measurements from magnetic resonance images (MRI) in subjects with palpable gouty tophi. Subjects first underwent radiographic imaging of a selected tophus followed by MRI before and at <or=5, 10 and 20-min after gadolinium administration. After choosing optimal parameters, subjects underwent pre- and postgadolinium-enhanced MRIs of a selected tophus on two occasions separated by 5-10 days. Unenhanced spin-echo images provided satisfactory tophi images and were less subject to interfering artefacts than gadolinium-enhanced gradient-echo images. Intrareader reproducibility was excellent, with no statistically significant difference in mean tophus volume between visits (mean difference - 0.05 +/- 0.97 cm3). A small but statistically significant difference in interreader mean tophus volume was detected (mean difference 0.89 +/- 2.05 cm3; p < 0.05). MRI can quantify tophus size in gout and deserves further comparison with other techniques for tophus size monitoring in assessing effects of gout therapy.

Febuxostat compared with allopurinol in patients with hyperuricemia and gout

BACKGROUND

Febuxostat, a novel nonpurine selective inhibitor of xanthine oxidase, is a potential alternative to allopurinol for patients with hyperuricemia and gout.

METHODS

We randomly assigned 762 patients with gout and with serum urate concentrations of at least 8.0 mg per deciliter (480 micromol per liter) to receive either febuxostat (80 mg or 120 mg) or allopurinol (300 mg) once daily for 52 weeks; 760 received the study drug. Prophylaxis against gout flares with naproxen or colchicine was provided during weeks 1 through 8. The primary end point was a serum urate concentration of less than 6.0 mg per deciliter (360 micromol per liter) at the last three monthly measurements. The secondary end points included reduction in the incidence of gout flares and in tophus area.

RESULTS

The primary end point was reached in 53 percent of patients receiving 80 mg of febuxostat, 62 percent of those receiving 120 mg of febuxostat, and 21 percent of those receiving allopurinol (P<0.001 for the comparison of each febuxostat group with the allopurinol group). Although the incidence of gout flares diminished with continued treatment, the overall incidence during weeks 9 through 52 was similar in all groups: 64 percent of patients receiving 80 mg of febuxostat, 70 percent of those receiving 120 mg of febuxostat, and 64 percent of those receiving allopurinol (P=0.99 for 80 mg of febuxostat vs. allopurinol; P=0.23 for 120 mg of febuxostat vs. allopurinol). The median reduction in tophus area was 83 percent in patients receiving 80 mg of febuxostat and 66 percent in those receiving 120 mg of febuxostat, as compared with 50 percent in those receiving allopurinol (P=0.08 for 80 mg of febuxostat vs. allopurinol; P=0.16 for 120 mg of febuxostat vs. allopurinol). More patients in the high-dose febuxostat group than in the allopurinol group (P=0.003) or the low-dose febuxostat group discontinued the study. Four of the 507 patients in the two febuxostat groups (0.8 percent) and none of the 253 patients in the allopurinol group died; all deaths were from causes that the investigators (while still blinded to treatment) judged to be unrelated to the study drugs (P=0.31 for the comparison between the combined febuxostat groups and the allopurinol group).

CONCLUSIONS

Febuxostat, at a daily dose of 80 mg or 120 mg, was more effective than allopurinol at the commonly used fixed daily dose of 300 mg in lowering serum urate. Similar reductions in gout flares and tophus area occurred in all treatment groups.

Tophaceous gout: quantitative evaluation by direct physical measurement

OBJECTIVE

The absence of accepted standardized methods for monitoring tophaceous gout limits the ability to track tophus progression or regression. This multicenter study assessed intra- and interrater reproducibility of a simple and direct physical measurement.

METHODS

The quantitative evaluation was the area (mm2) of each measurable tophus and was determined independently by 2 raters on 2 occasions within 10 days. Intra- and interrater reproducibilities were determined by calculating mean differences and average percentage differences (APD) in measurements of areas for the same tophus at each of 2 visits and by each rater, respectively.

RESULTS

Fifty-two tophi were measured in 13 subjects: 22 on the hand/wrist, 16 on the elbow, and 14 on the foot/ankle. The mean (+/- SD) difference in tophus areas between visits was -0.2 +/- 835 mm2 (95% CI -162 to 162 mm2) and the mean (+/- SD) APD was 29% +/- 33%. The mean (+/- SD) APD between raters was 32% +/- 27%. The largest variations in measurements were noted for elbow tophi and variations were least for well demarcated tophi on the hands.

CONCLUSION

This simple and reproducible method can be easily utilized in clinical trials and in practice as a measure of efficacy of urate-lowering treatment in tophaceous gout. Among factors contributing to variability in these measurements were the anatomic site of tophi and rater experience with the method. Restriction of measurements to well circumscribed hand or foot tophi could improve reliability, but major changes, as expected with effective therapy, can clearly be documented with this simple technique.

Febuxostat, a novel nonpurine selective inhibitor of xanthine oxidase: a twenty-eight-day, multicenter, phase II, randomized, double-blind, placebo-controlled, dose-response clinical trial examining safety and efficacy in patients with gout

OBJECTIVE

Gout affects approximately 1-2% of the American population. Current options for treating hyperuricemia in chronic gout are limited. The purpose of this study was to assess the safety and efficacy of febuxostat, a nonpurine selective inhibitor of xanthine oxidase, in establishing normal serum urate (sUA) concentrations in gout patients with hyperuricemia (>or=8.0 mg/dl).

METHODS

We conducted a phase II, randomized, double-blind, placebo-controlled trial in 153 patients (ages 23-80 years). Subjects received febuxostat (40 mg, 80 mg, 120 mg) or placebo once daily for 28 days and colchicine prophylaxis for 14 days prior to and 14 days after randomization. The primary end point was the proportion of subjects with sUA levels <6.0 mg/dl on day 28.

RESULTS

Greater proportions of febuxostat-treated patients than placebo-treated patients achieved an sUA level <6.0 mg/dl at each visit (P < 0.001 for each comparison). The targeted sUA level was attained on day 28 in 0% of those taking placebo and in 56% of those taking 40 mg, 76% taking 80 mg, and 94% taking 120 mg of febuxostat. The mean sUA reduction from baseline to day 28 was 2% in the placebo group and 37% in the 40-mg, 44% in the 80-mg, and 59% in the 120-mg febuxostat groups. Gout flares occurred with similar frequency in the placebo (37%) and 40-mg febuxostat (35%) groups and with increased frequency in the higher dosage febuxostat groups (43% taking 80 mg; 55% taking 120 mg). During colchicine prophylaxis, gout flares occurred less frequently (8-13%). Incidences of treatment-related adverse events were similar in the febuxostat and placebo groups.

CONCLUSION

Treatment with febuxostat resulted in a significant reduction of sUA levels at all dosages. Febuxostat therapy was safe and well tolerated.

Investigating a memory-based account of negative priming: support for selection-feature mismatch

Using typical and modified negative priming tasks, the selection-feature mismatch account of negative priming was tested. In the modified task, participants performed selections on the basis of a semantic feature (e.g., referent size). This procedure has been shown to enhance negative priming (P. A. MacDonald, S. Joordens, & K. N. Seergobin, 1999). Across 3 experiments, negative priming occurred only when the repeated item mismatched in terms of the feature used as the basis for selections. When the repeated item was congruent on the selection feature across the prime and probe displays, positive priming arose. This pattern of results appeared in both the ignored- and the attended-repetition conditions. Negative priming does not result from previously ignoring an item. These findings strongly support the selection-feature mismatch account of negative priming and refute both the distractor inhibition and the episodic-retrieval explanations.

Investigating a memory-based account of negative priming: support for selection-feature mismatch

Using typical and modified negative priming tasks, the selection-feature mismatch account of negative priming was tested. In the modified task, participants performed selections on the basis of a semantic feature (e.g., referent size). This procedure has been shown to enhance negative priming (P. A. MacDonald, S. Joordens, & K. N. Seergobin, 1999). Across 3 experiments, negative priming occurred only when the repeated item mismatched in terms of the feature used as the basis for selections. When the repeated item was congruent on the selection feature across the prime and probe displays, positive priming arose. This pattern of results appeared in both the ignored- and the attended-repetition conditions. Negative priming does not result from previously ignoring an item. These findings strongly support the selection-feature mismatch account of negative priming and refute both the distractor inhibition and the episodic-retrieval explanations.

Negative priming for obsessive-compulsive checkers and noncheckers

Negative priming--the slowing of a response to an item that was recently ignored--was investigated in three groups: obsessive-compulsive disorder (OCD) checkers, OCD noncheckers, and nonclinical control participants. All groups performed both a standard negative priming task, selecting targets based on a perceptual feature (i.e., color), and a modified negative priming task, selecting targets based on a semantic feature (i.e., referent size). All three groups demonstrated significant negative priming in both tasks, although the negative priming was much larger in the novel, semantic task than in the common, perceptual one. The findings suggest that patients with OCD do not demonstrate impairments in negative priming, contrary to earlier claims (Enright & Beech, 1990, 1993a, 1993b; Enright, Beech, & Claridge, 1995).

Negative priming for obsessive-compulsive checkers and noncheckers

Negative priming--the slowing of a response to an item that was recently ignored--was investigated in three groups: obsessive-compulsive disorder (OCD) checkers, OCD noncheckers, and nonclinical control participants. All groups performed both a standard negative priming task, selecting targets based on a perceptual feature (i.e., color), and a modified negative priming task, selecting targets based on a semantic feature (i.e., referent size). All three groups demonstrated significant negative priming in both tasks, although the negative priming was much larger in the novel, semantic task than in the common, perceptual one. The findings suggest that patients with OCD do not demonstrate impairments in negative priming, contrary to earlier claims (Enright & Beech, 1990, 1993a, 1993b; Enright, Beech, & Claridge, 1995).

Negative priming effects that are bigger than a breadbox: attention to distractors does not eliminate negative priming, it enhances it

In a series of experiments, we examined the effect of requiring subjects to attend to distractors in a test of negative priming. This was accomplished by using a referent size-selection task in which subjects were instructed to name the larger animal and to ignore the smaller animal in a word pair. The result was a quadrupling of the standard negative priming effect, suggesting that negative priming not only occurs for attended distractors, it is actually enhanced. We demonstrated that this enhancement of the effect was not due solely to increased latencies in the referent size-selection task, because neither decreasing base response times in other referent size-selection tasks nor increasing base response times in typical color-selection tasks substantially affected the respective negative priming effects. Although these findings can be accommodated within current theories of negative priming, they challenge the basic assumption that the negative priming effect arises because the critical item was ignored or not attended to on the prime trial.

The influence of attention at encoding on direct and indirect remembering

The relation between attention at encoding and direct (i.e., recognition) versus indirect (i.e., rapid reading) remembering was investigated. In Experiments 1 and 2, color of print indicated whether to read an individual word aloud or to ignore it. This attentional manipulation reduced direct but not indirect remembering for the ignored words relative to the attended words. Apparently direct remembering is extremely dependent on attention at encoding. In Experiment 3, however, presenting two words simultaneously at study, with color now signifying which word to read and which to ignore, eliminated this dissociative effect of attention. Ignored words were not remembered on either test, although attended words were remembered well on both. Mere exposure is not sufficient to produce indirect remembering: Stimuli must be attended. Ignoring one stimulus in favor of processing another stimulus that is simultaneously presented and equally salient may prevent even the minimal attentional requirements of indirect remembering from being met, let alone the more stringent requirements of direct remembering.

Memory and confidence in memory judgements among individuals with obsessive compulsive disorder and non-clinical controls

The present study investigated episodic memory functioning in: (1) obsessive compulsive disorder (OCD) patients with primarily checking symptoms (i.e. checkers); (2) OCD patients without checking symptoms (i.e. non-checkers); and (3) non-clinical control participants. On a measure of recall, all groups were statistically equivalent with respect to the proportion of words correctly recalled. Using a recognition measure, checkers were unimpaired in episodic memory, as compared to non-checkers and non-clinical controls. However, relative to the other groups, patients with checking symptoms showed decreased confidence in their correct and incorrect recognition memory judgements, according to their item-by-item self-report confidence ratings. When checkers correctly identified previously seen words, they were also slower to respond than were the other groups, supporting the view that they were less confident in their memory judgments relative to the other groups, which did not differ on this measure. The results of the present study suggest that OCD checking is not related to memory impairments per se but rather that checking in OCD is a symptom of decreased confidence in memory.

Measles in the 1980s

We detail aspects of measles immunization programmes in several countries. Live measles vaccine has been available in Australia for 16 years, yet, in 1981, there were outbreaks of measles in the State of New South Wales (population 5 200 000) which led to 2200 admissions to hospital and five deaths. In response to complaints of "vaccine failure", a survey determined that 22.5% of children with measles seen by general practitioners and 10.3% of those admitted to hospitals had been previously immunized. There was no evidence of waning immunity, and noparticular batch of vaccine was implicated. The vaccine failures are attributed in part to failure of seroconversion in some recipients when immunized at 12 months of age as a result of interference by transplacentally acquired antibodies. As more of the susceptible population is vaccinated, there will be fewer cases of measles, but among these cases will be an increasing proportion of cases occurring in previously vaccinated individuals. The equation to calculate this expected proportion of "vaccine failures" is given. We support the measures to increase immunization compliance.