Febuxostat in the management of gout: a cost-effectiveness analysis

Efficacy and Safety of Allopurinol and Febuxostat in Patients With Gout and CKD: Subgroup Analysis of the STOP Gout Trial

RATIONALE & OBJECTIVE

We conducted a prespecified examination of the efficacy and safety of allopurinol and febuxostat administered using a treat-to-target strategy in trial participants with chronic kidney disease (CKD).

STUDY DESIGN

Prespecified sub cohort analysis of a randomized controlled trial.

SETTING

& Participants: A sub study of the STOP Gout trial in participants with CKD. CKD was defined as an eGFR 30-59 mL/min/1.73 m2 at baseline.

EXPOSURE

Trial participants with CKD and gout and serum urate (sUA) concentration ≥6.8 mg/dL were randomized 1:1 to receive allopurinol or febuxostat. Urate lowering therapy (ULT) was titrated during weeks 0-24 to achieve a goal sUA of <6.0 mg/dl (<5.0 mg/dl with tophi) (Phase 1) and maintained during weeks 25-48 (Phase 2). Gout flare was assessed between weeks 49-72 (Phase 3).

OUTCOME

Gout flare between weeks 49-72 (Phase 3) was the primary outcome. Secondary outcomes included sUA goal achievement and ULT dosing at end of Phase 2, and serious adverse events (SAEs).

ANALYTICAL APPROACH

Outcomes between treatment groups were compared using logistic regression models for binary outcomes, and Poisson regression for flare rates. Multivariable models were subsequently used, adjusting for factors identified to be imbalanced by treatment arm.

RESULTS

351 of 940 participants (37.3%) had CKD; 277 were assessed for the primary outcome. Fewer patients randomized to allopurinol had a flare during phase 3 (32% vs 45%; p=0.02) despite similar attainment of sUA goal (79% vs. 81%; p=0.6) by the end of Phase 2. Acute kidney injury (AKI) was more common in participants with stage 3 CKD randomized to allopurinol compared to febuxostat.

LIMITATIONS

Limited power to assess infrequent safety events, largely male, older population.

CONCLUSIONS

Allopurinol and febuxostat are similarly efficacious and well-tolerated in the treatment of gout in people with CKD when used in a treat-to-target regimen.

Effect of febuxostat on renal function in patients from South China with CKD3 diabetic nephropathy

OBJECTIVE

To investigate the efficacy and safety of febuxostat on renal function in CKD stage 3 diabetic nephropathy patients.

METHODS

Patients in our hospital with chronic kidney disease (CKD) stage 3 diabetic nephropathy (DN) complicated by high serum uric acid (360 µmol/L) were recruited. Patients were then divided into treatment group and control group according to the random number table method. All the patients received low purine diet, renin-angiotensin-aldosterone system (RAAS) inhibitors, and adequate routine hypoglycemic treatment. Febuxostat was employed only in the treatment group. The levels of blood uric acid (sUA), serum creatinine (Scr), cystatin C (cys-c), eGFR, 24-hour urine protein quantification, albuminuria, and creatinine ratio (ACR) were evaluated in all patients before and after treatment at 4, 8, 12, and 24 week.

RESULTS

No difference was found before treatment between the two groups. After treatment at 4, 8, 12, and 24 week, the levels of sUA, SCr, cys-c, and eGFR between the two groups were significant different (P<0.05). There was no difference in 24-hour urine protein quantification, albuminuria, and creatinine ratio between two groups before treatment, and significant differences were observed after treatment. Fifty percent of patients from the treatment group achieved the treatment goal with 20 mg febuxostat at 4 weeks. Tubular markers were also decreased with the treatment.

CONCLUSIONS

Febuxostat can reduce uric acid and improve renal function effectively in patients with CKD stage 3 diabetic nephropathy, while being well tolerated. However, the conclusion is still uncertain due to the short term of the study.

Cost-effectiveness of allopurinol versus febuxostat in the treatment of gout patients: A systematic review

Background: In recent years, increased longevity, poor dietary habits, and the rising prevalence of metabolic syndrome and hypertension have increased the prevalence of gout. Gout significantly increases direct and indirect costs and reduces the quality of life. Allopurinol and febuxostat are the most commonly used drugs for reducing uric acid levels and controlling this disease with different cost-effectiveness. The present systematic review compares the cost-effectiveness of these drugs. Methods: This was a systematic review of economic evaluations. Cochrane CENTRAL, Web of Science, PubMed, Embase, and the Cost-Effectiveness Analysis (CEA) Registry were searched up to April 30, 2018, based on the specific search strategy of each database. Keywords used in the search include gout, cost-effectiveness, allopurinol, and febuxostat in MeSH and free-text forms. Screening of identified studies, data extraction, and quality assessment were done independently by 2 reviewers. The quality of studies was assessed based on Drummond Checklist. Finally, a qualitative analysis was done to analyze the results. Results: A total of 94 studies were identified through database search and the review of references. After screening the titles, abstracts, and full-texts, 6 economic evaluations were included in the review. The majority of the studies had been conducted in the US using the Markov model, within a 5-year horizon, and from the payer's perspective, with the quality of life as a measure of effectiveness. In most studies, the incremental cost-effectiveness ratios (ICERs) of febuxostat per quality-adjusted life year (QALY) were below the threshold (10 000$/QALY and 30 000€/QALY). Conclusion: Febuxostat has been shown to be more cost-effective than allopurinol in all treatment sequences in studies that have used uric acid levels as the measure of effectiveness. Furthermore, in studies with the quality of life as the measure of effectiveness, febuxostat has been shown to be very cost-effective as the second-line treatment.

Cost-effectiveness of an adherence-enhancing intervention for gout based on real-world data

AIM

Medication non-adherence influences outcomes of therapies for chronic diseases. Allopurinol is a cornerstone therapy for patients with gout; however, non-adherence to allopurinol is prevalent in Singapore and limits its effectiveness. Between 2008-2010, an adherence-enhancing program was implemented at the rheumatology division of a public tertiary hospital. The cost-effectiveness of this program has not been fully evaluated. With healthcare resources being finite, the value of investing in adherence-enhancing interventions should be ascertained. This study aims to evaluate the cost-effectiveness of this adherence-enhancing program to inform optimal resource allocation toward better gout management.

METHOD

Adopting a real-world data approach, we utilized patient clinical and financial records generated in their course of routine care. Intervention and control groups were identified in a standing database and matched on nine risk factors through propensity score matching. Cost and effect data were followed through 1-2 years. A decision tree was developed in TreeAge using a societal perspective. Deterministic and probabilistic sensitivity analyses were performed to assess parameter uncertainty.

RESULTS

At an assumed willingness-to-pay threshold of $50 000 USD ($70 000 SGD) per quality-adjusted life year (QALY), the intervention had an 85% probability of being cost-effective compared to routine care. The incremental cost-effectiveness ratio was $12 866 USD per QALY for the base case and ranged from $4 139 to $21 593 USD per QALY in sensitivity analyses.

CONCLUSION

The intervention is cost-effective in the short-term, although its long-term cost-effectiveness remains to be evaluated.

Management of gout and hyperuricemia: Multidisciplinary consensus in Taiwan

Gout is an inflammatory disease manifested by the deposition of monosodium urate (MSU) crystals in joints, cartilage, synovial bursa, tendons or soft tissues. Gout is not a new disease, which was first documented nearly 5,000 years ago. The prevalence of gout has increased globally in recent years, imposing great disease burden worldwide. Moreover, gout or hyperuricemia is clearly associated with a variety of comorbidities, including cardiovascular diseases, chronic kidney disease, urolithiasis, metabolic syndrome, diabetes mellitus, thyroid dysfunction, and psoriasis. To prevent acute arthritis attacks and complications, earlier use of pharmacotherapeutic treatment should be considered, and patients with hyperuricemia and previous episodes of acute gouty arthritis should receive long-term urate-lowering treatment. Urate-lowering drugs should be used during the inter-critical and chronic stages to prevent recurrent gout attacks, which may elicit gradual resolution of tophi. The goal of urate-lowering therapy should aim to maintain serum uric acid (sUA) level <6.0 mg/dL. For patients with tophi, the initial goal can be set at lowering sUA to <5.0 mg/dL to promote tophi dissolution. The goal of this consensus paper was to improve gout and hyperuricemia management at a more comprehensive level. The content of this consensus paper was developed based on local epidemiology and current clinical practice, as well as consensuses from two multidisciplinary meetings and recommendations from Taiwan Guideline for the Management of Gout and Hyperuricemia.

Management of Gout and Hyperuricemia in CKD

Hyperuricemia and gout, the clinical manifestation of monosodium urate crystal deposition, are common in patients with chronic kidney disease (CKD). Although the presence of CKD poses additional challenges in gout management, effective urate lowering is possible for most patients with CKD. Initial doses of urate-lowering therapy are lower than in the non-CKD population, whereas incremental dose escalation is guided by regular monitoring of serum urate levels to reach the target level of <6mg/dL (or <5mg/dL for patients with tophi). Management of gout flares with presently available agents can be more challenging due to potential nephrotoxicity and/or contraindications in the setting of other common comorbid conditions. At present, asymptomatic hyperuricemia is not an indication for urate-lowering therapy, though emerging data may support a potential renoprotective effect.