How is leflunomide prescribed and used in Australia? Analysis of prescribing and adverse effect reporting

Leflunomide in Pakistani patients with rheumatoid arthritis: prospective study in daily rheumatology practice

INTRODUCTION

Leflunomide is a disease-modifying anti-rheumatic drug (DMARD) for rheumatoid arthritis (RA). It has been widely studied in the West but there is no available local Pakistani data.

OBJECTIVE

To evaluate the efficacy and safety profile of leflunomide in Pakistani patients with RA, either alone or in combination with methotrexate.

MATERIALS AND METHODS

A prospective, non-comparator, open-label study in a setting of 'care as usual' was performed. In this study, 63 consecutive RA patients on leflunomide were enrolled. Leflunomide dose was started with full loading in 5 (8%), half loading in 39 (62%) and without loading in 19 (30%) patients. Methotrexate was also used in 20 (32%) patients. Primary end-point was 20% improvement in American College of Rheumatology response criteria (ACR-20). Safety was assessed by adverse events and abnormalities in laboratory parameters.

RESULTS

Out of 63 patients, 54 (85.7%) were female. Mean age was 46 ± 12.6 years. Mean disease duration was 5.1 ± 4.5 years. Fifty-two (86.6%) patients achieved ACR-20 response at 6 months; 32 (53%) achieved ACR-50 response at 6 months; 20% experienced at least one adverse event, which resolved by reducing leflunomide dose. Only seven (11%) had raised liver enzymes from baseline.

CONCLUSION

This prospective study conducted in the setting of a daily rheumatology practice shows that leflunomide is an effective and safe DMARD in treatment of RA in Pakistani patients.

Efficacy of leflunomide for treatment of immune-mediated polyarthritis in dogs: 14 cases (2006-2008)

OBJECTIVE

To evaluate efficacy and adverse effects of leflunomide for the treatment of naturally occurring immune-mediated polyarthritis (IMPA) in dogs.

DESIGN

Retrospective case series.

ANIMALS

14 dogs with cytologically confirmed IMPA.

PROCEDURES

Medical records were used to identify dogs with a diagnosis of IMPA that were treated with leflunomide. Signalment, radiographic findings, laboratory data, dosage of leflunomide, treatment duration, treatment response, and occurrence of adverse effects were determined from medical records.

RESULTS

Mean +/- SD initial dosage of leflunomide was 3.0 +/- 0.5 mg/kg (1.4 +/- 0.2 mg/lb) PO once daily. Treatment duration for the initial starting dosage ranged from 1 to 6 weeks. Of the 14 dogs treated with leflunomide, 8 had complete resolution of clinical signs of IMPA initially, 5 had partial response to treatment, and 1 had minimal response to treatment. Adverse effects from treatment with leflunomide were not observed during the treatment period.

CONCLUSIONS AND CLINICAL RELEVANCE

Oral administration of leflunomide was a safe and effective alternative to oral administration of corticosteroids for treatment of IMPA in dogs. On the basis of findings in this study, a starting dosage for leflunomide of 3 to 4 mg/kg (1.4 to 1.8 mg/lb) PO once daily for at least 6 weeks before making dose adjustments is recommended. Dose adjustments should be based on cytologic evaluation of synovial fluid and clinical signs of IMPA. Hematologic variables, serum biochemical analysis results, and clinical signs of IMPA should be monitored for evidence of adverse effects to treatment with leflunomide.

Leflunomide use in New Zealand. A national prospective post-marketing study

BACKGROUND

This post-marketing study aimed to record rates of retention, adverse effects and efficacy of leflunomide in the treatment of rheumatoid arthritis (RA). The secondary objectives were to make a semi-quantitative assessment of response to treatment and to examine the effect of a loading dose on adverse events and treatment duration.

METHODS

Rheumatologists in New Zealand contributed to a prospective leflunomide treatment registry. Baseline data were collected on leflunomide initiation and information about treatment experience was sought every 6 months. Each patient was followed for 2 years. Kaplan-Meier analysis was used to evaluate differences in stopping rates between lack of efficacy and adverse effects. Hazard analysis was used to evaluate the effect of using a loading dose on retention rate.

RESULTS

Three hundred and eight patients were enrolled in the study; complete follow-up data were available for 244 patients. Retention of patients on leflunomide was 64% at 12 months and 49.4% at 2 years. Reasons for stopping were adverse events (54 patients), loss of effect (25 patients) and miscellaneous reasons (14 patients). Use of a loading dose had no effect on retention; there was no difference in treatment duration between those who stopped from adverse effects or loss of efficacy.

CONCLUSION

Leflunomide was effective in treating RA in a group that had longer duration of disease and greater prior use of disease-modifying agents than the groups studied in clinical trials. Rates of withdrawal were lower than those reported in other post-marketing studies, but were higher than those from phase III clinical trials.

Why is the use of clopidogrel increasing rapidly in Australia? An exploration of geographical location, age, sex and cardiac stenting rates as possible influences on clopidogrel use

PURPOSE

To explore clopidogrel use within Australia, investigating geography, age, sex and cardiac stenting rates.

METHODS

Data for clopidogrel supply (Pharmaceutical Benefits Scheme (PBS) and Repatriation Pharmaceutical Benefits Scheme (RPBS)) and cardiac stenting procedures (State Health Departments) were obtained for four different geographic regions (very remote/remote and major city in two Australian states). General linear modelling and correlation analyses were used to test for associations and chi2 analyses for proportions.

RESULTS

Clopidogrel supply increased rapidly in Australia since introduction, from 1.2 to 9.0 Defined Daily Doses (DDD)/1000 population/day. Among concessional and veteran populations use was much higher. Analysis of geographical area data confirmed an association between clopidogrel supply rates and cardiac stenting rates (r = 0.8-0.9 Spearman's rho, p < 0.01). Sex, age and geographical location were associated with both rates when considered together and when considered independently. Further modelling indicated that between 30 and 73% of clopidogrel supply could be accounted for by people receiving cardiac stents.

CONCLUSIONS

The supply of clopidogrel increases with age, male sex and living in a major city. These same demographic variables were important for cardiac stenting, an indication which is currently not approved for subsidy by the Australian government, but which modelling indicated could account for between one-third and three quarters of clopidogrel use. A review may be required to ensure subsidised indications reflect current evidence and cost-effective use.

Higher levels of leflunomide are associated with hemolysis and are not superior to lower levels for BK virus clearance in renal transplant patients

BACKGROUND AND OBJECTIVES

Leflunomide use in renal transplantation has been increasing. Outcome correlation and safety data are still to be refined. The goals of this study were to report one center's experience with leflunomide, specifically the correlation of leflunomide levels with the outcomes of BK nephropathy and the observed toxic effects during the treatment with leflunomide.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Leflunomide was used in 21 patients with BK nephropathy. These patients were divided into two groups on the basis of the leflunomide levels achieved: Low-level group (<40 microg/ml) and high-level group (>40 microg/ml).

RESULTS

During 13 mo of follow-up, there was no difference in the rate of serum BK viral clearance between the groups. There were three graft losses in the low-level group and one in the high-level group; however, creatinine levels were higher at the time of starting leflunomide in the low-level group. Leflunomide was also used in six patients with chronic allograft injury. No graft loss was observed during the follow-up period of 16 mo. Treatment with leflunomide seemed to be associated with a new toxicity, hemolysis, seen in four of the 27 patients so treated. Patients with hemolysis had high leflunomide levels (81.4 +/- 14 microg/ml) and worsening allograft function. Two patients had histologic evidence of thrombotic microangiopathy, which led to graft loss in one patient.

CONCLUSIONS

The clinical correlation between leflunomide levels and outcomes needs to be further refined. This study described a possible association of leflunomide with thrombotic microangiopathy, especially at higher levels.