Conversion to generic cyclosporine A in stable chronic patients after heart transplantation

The Impact of Spironolactone Co-administration on Cyclosporin Initial Dosage Optimization for Pediatric Refractory Nephrotic Syndrome

OBJECTIVES

Cyclosporin has been used for the treatment of pediatric refractory nephrotic syndrome (PRNS). However, the narrow therapeutic window and large pharmacokinetic variability make it difficult to individualize cyclosporin administration. Meanwhile, spironolactone has been reported to affect cyclosporin metabolism in PRNS patients. This study aims to explore the initial dosage optimization of cyclosporin in PRNS based on the impact of spironolactone co-administration.

METHODS

Monte Carlo simulation based on a previously established cyclosporin population pharmacokinetic model for PRNS was used to design cyclosporin dosing regimen.

RESULTS

In this study, the probability of drug concentration reaching the target and the convenience of times of administration were considered comprehensively. The optimal administration regimen in PRNS without spironolactone was 6, 5, 4 and 3 mg/kg cyclosporin split into two doses for the body weight of 5-8, 8-18, 18-46 and 46-70 kg, respectively. The optimal administration regimen in PRNS with spironolactone was 4, 3, 2 mg/kg cyclosporin split into two doses for body weight of 5-14, 14-65, and 65-70 kg, respectively.

CONCLUSION

The cyclosporin dosing regimen for PRNS based on Monte Carlo simulation was systematically developed and the initial dosage optimization of cyclosporin in PRNS was recommended for the first time.

Efficacy and safety of a conversion from the original tacrolimus and mycophenolate mofetil to the generics Tacpan and Mowel after liver transplantation

Background

Expensive pharmaceuticals are a major reason for cost intensive health care systems. Long-term immunosuppressive therapy plays a relevant role after organ transplantation. Patents of original drugs have expired and cheaper products are available. Little data are available regarding efficacy and safety of generic immunosuppressive agents.

Methods

In this prospective study, 25 patients, who were clinically stable for a minimum of 2 years after liver transplantation, were converted from the original formulations of tacrolimus (TAC) and mycophenolate mofetil to the generics Tacpan^® (TAP) and Mowel^® (MOW). Patients were followed-up for 6 months. Results were compared retrospectively to 25 age- and sex-matched controls treated with the original brands.

Results

In the matched-pair analysis of TAC trough level/dose ratio, no significant difference was found between TAP/MOW and TAC/mycophenolate mofetil groups. No acute rejection occurred in either group. In total, 17 patients reported mild side effects in the TAP/MOW group. The most common side effects were gastrointestinal symptoms. Intra-individual analysis of costs revealed a considerable cost reduction in the TAP/MOW group (in median 25.03%; P<0.001).

Conclusion

In summary, the use of the generics TAP/MOW is effective and seems to be safe and cost-efficient in stable liver-transplantation patients.

Generic immunosuppression in solid organ transplantation: systematic review and meta-analysis

OBJECTIVE

To compare the clinical efficacy and bioequivalence of generic immunosuppressive drugs in patients with solid organ transplants.

DESIGN

Systematic review and meta-analysis of all studies comparing generic with innovator immunosuppressive drugs.

DATA SOURCES

Medline and Embase from 1980 to September 2014.

REVIEW METHODS

A literature search was performed for all studies comparing a generic to an innovator immunosuppressive drug in solid organ transplantation. Two reviewers independently extracted data and assessed quality of studies. Meta-analyses of prespecified outcomes were performed when deemed appropriate. Outcomes included patient survival, allograft survival, acute rejection, adverse events and bioequivalence.

RESULTS

1679 citations were screened, of which 50 studies met eligibility criteria (17 randomized trials, 15 non-randomized interventional studies, and 18 observational studies). Generics were compared with Neoral (cyclosporine) (32 studies), Prograf (tacrolimus) (12 studies), and Cellcept (mycophenolate mofetil) (six studies). Pooled analysis of randomized controlled trials in patients with kidney transplants that reported bioequivalence criteria showed that Neoral (two studies) and Prograf (three studies) were not bioequivalent with generic preparations according to criteria of the European Medicines Agency. The single Cellcept trial also did not meet bioequivalence. Acute rejection was rare but did not differ between groups. For Neoral, the pooled Peto odds ratio was 1.23 (95% confidence interval 0.64 to 2.36) for kidney randomized controlled trials and 0.66 (0.40 to 1.08) for observational studies. For kidney observational studies, the pooled Peto odds ratios were 0.98 (0.37 to 2.60) for Prograf and 0.49 (0.09 to 2.56) for Cellcept. Meta-analyses for non-renal solid organ transplants were not performed because of a lack of data.There were insufficient data reported on patient or graft survival. Pooling of results was limited by inconsistent study methods and reporting of outcomes. Many studies did not report standard criteria used to determine bioequivalence. While rates of acute rejection seemed similar and were relatively rare, few studies were designed to properly compare clinical outcomes. Most studies had short follow-up times and included stable patients without a history of rejection.

CONCLUSIONS

High quality data showing bioequivalence and clinical efficacy of generic immunosuppressive drugs in patients with transplants are lacking. Given the serious consequences of rejection and allograft failure, well designed studies on bioequivalence and safety of generic immunosuppression in transplant recipients are needed.