Generic cyclosporine formulations: more open questions than answers

Atopic dermatitis (eczema) guidelines: 2023 American Academy of Allergy, Asthma and Immunology/American College of Allergy, Asthma and Immunology Joint Task Force on Practice Parameters GRADE- and Institute of Medicine-based recommendations

BACKGROUND

Guidance addressing atopic dermatitis (AD) management, last issued in 2012 by the American Academy of Allergy, Asthma and Immunology/American College of Allergy, Asthma and Immunology Joint Task Force, requires updating as a result of new treatments and improved guideline and evidence synthesis methodology.

OBJECTIVE

To produce evidence-based guidelines that support patients, clinicians, and other decision-makers in the optimal treatment of AD.

METHODS

A multidisciplinary guideline panel consisting of patients and caregivers, AD experts (dermatology and allergy/immunology), primary care practitioners (family medicine, pediatrics, internal medicine), and allied health professionals (psychology, pharmacy, nursing) convened, prioritized equity, diversity, and inclusiveness, and implemented management strategies to minimize influence of conflicts of interest. The Evidence in Allergy Group supported guideline development by performing systematic evidence reviews, facilitating guideline processes, and holding focus groups with patient and family partners. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach informed rating the certainty of evidence and strength of recommendations. Evidence-to-decision frameworks, subjected to public comment, translated evidence to recommendations using trustworthy guideline principles.

RESULTS

The panel agreed on 25 recommendations to gain and maintain control of AD for patients with mild, moderate, and severe AD. The eAppendix provides practical information and implementation considerations in 1-2 page patient-friendly handouts.

CONCLUSION

These evidence-based recommendations address optimal use of (1) topical treatments (barrier moisturization devices, corticosteroids, calcineurin inhibitors, PDE4 inhibitors [crisaborole], topical JAK inhibitors, occlusive [wet wrap] therapy, adjunctive antimicrobials, application frequency, maintenance therapy), (2) dilute bleach baths, (3) dietary avoidance/elimination, (4) allergen immunotherapy, and (5) systemic treatments (biologics/monoclonal antibodies, small molecule immunosuppressants [cyclosporine, methotrexate, azathioprine, mycophenolate, JAK inhibitors], and systemic corticosteroids) and UV phototherapy (light therapy).

Immunosuppression with Generics in Liver and Kidney Transplantation: A Real-World Evidence Study

Purpose

This study evaluates the use, benefit-risk profile, and economic impact of generic immunosuppressants (tacrolimus-TAC, cyclosporine-CsA, and mycophenolate-MYC) in kidney and liver transplant recipients compared to brand-name drugs.

Patients and Methods

A retrospective multicentre observational study, involving four Italian regions, was conducted based on the national transplant Information system and regional healthcare claims data. The analysis focused on incident patients who received kidney and liver transplants between 2013 and 2019 and evaluated the use of generic of CsA, TAC, and MYC during the 30-day period following discharge. For each type of transplant and immunosuppressive agent, the benefit-risk profile of generic vs branded drugs in a two-year window was estimated by multivariate Cox models (HR; 95% CI). Furthermore, the potential cost savings per person associated with one year of treatment using generics were calculated.

Results

The utilization of generic drugs showed a significant increase; over the study years, the proportion of users among kidney recipients ranged from 14.2% to 40.5% for TAC, from 36.9% to 56.7% for MYC, and from 18.2% to 94.7% for CsA. A great variability in generic uptake for region was found. A comparable risk-benefit profile between generic and branded formulations was shown for all immunosuppressors considered. Choosing generic immunosuppressants during maintenance could result in yearly savings of around 2000 euros per person for each therapy ingredient.

Conclusion

The study shows an increasing proportion of patients using generic immunosuppressive drugs over time suggesting a growing acceptance of generics within the transplant community and reveals comparable risk-benefit profiles between the generic and branded formulations of TAC, CsA, and MYC. A significant variability in the use of generics immunosuppressive agents was found both at the regional level and among transplant centers and future research should delve into regional prescribing variations.

An Italian multicentre distributed data research network to study the use, effectiveness, and safety of immunosuppressive drugs in transplant patients: Framework and perspectives of the CESIT project

The goal of post-transplant immunosuppressive drug therapy is to prevent organ rejection while minimizing drug toxicities. In clinical practice, a multidrug approach is commonly used and involves drugs with different mechanisms of action, including calcineurin inhibitors (CNI) (tacrolimus or cyclosporine), antimetabolite (antimet) (mycophenolate or azathioprine), inhibitors of mechanistic target of rapamycin (mTOR) (sirolimus or everolimus), and/or steroids. Although evidence based on several randomized clinical trials is available, the optimal immunosuppressive therapy has not been established and may vary among organ transplant settings. To improve the knowledge on this topic, a multiregional research network to Compare the Effectiveness and Safety of Immunosuppressive drugs in Transplant patients (CESIT) has been created with the financial support of the Italian Medicines Agency. In this article, we describe the development of this network, the framework that was designed to perform observational studies, and we also give an overview of the preliminary results that we have obtained. A multi-database transplant cohort was enrolled using a common data model based on healthcare claims data of four Italian regions (Lombardy, Veneto, Lazio, and Sardinia). Analytical datasets were created using an open-source tool for distributed analysis. To link the National Transplant Information System to the regional transplant cohorts, a semi-deterministic record linkage procedure was performed. Overall, 6,914 transplant patients from 2009-19 were identified: 4,029 (58.3%) for kidney, 2,219 (32.1%) for liver, 434 (6.3%) for heart, and 215 (3.1%) for lung. As expected, demographic and clinical characteristics showed considerable variability among organ settings. Although the triple therapy in terms of CNI + antimet/mTOR + steroids was widely dispensed for all settings (63.7% for kidney, 33.5% for liver, 53.3% for heart, and 63.7% for lung), differences in the active agents involved were detected. The CESIT network represents a great opportunity to study several aspects related to the use, safety, and effectiveness of post-transplant maintenance immunosuppressive therapy in real practice.

Molecular Dynamics Simulations and Experimental Results Provide Insight into Clinical Performance Differences between Sandimmune® and Neoral® Lipid-Based Formulations

OBJECTIVE

Molecular dynamics (MD) simulations provide an in silico method to study the structure of lipid-based formulations (LBFs) and the incorporation of poorly water-soluble drugs within such formulations. In order to validate the ability of MD to effectively model the properties of LBFs, this work investigates the well-known cyclosporine A formulations, Sandimmune® and Neoral®. Sandimmune® exhibits poor dispersibility and its absorption from the gastrointestinal tract is enhanced when administered after food, whereas Neoral® disperses comparatively well and shows no food effect.

METHODS

MD simulations were performed of both LBFs to investigate the differences observed in fasted and fed conditions. These conditions were also tested using an in vitro experimental model of dispersion and digestion.

RESULTS

These MD simulations were able to show that the food effect observed for Sandimmune® can be explained by large changes in drug solubilization on addition of bile. In contrast, Neoral® is well dispersed in water or in simulated fasted conditions, and this dispersion is relatively unchanged on moving to fed conditions. These differences were confirmed using dispersion and digestion in vitro experimental model.

CONCLUSIONS

The current data suggests that MD simulations are a potential method to model the fate of LBFs in the gastrointestinal tract, predict their dispersion and digestion, investigate behaviour of APIs within the formulations, and provide insights into the clinical performance of LBFs.

Cyclosporine CsA—The Physicochemical Characterization of Liposomal and Colloidal Systems

This paper presents an overview of the possibilities of testing various cyclosporine (CsA) formulations with an emphasis on parameters that may be key to improving the stability and biocompatibility. The feasibility of CsA colloidal systems for oral (injection) administration were investigated using different techniques and compared with similar investigations of other researchers. The chosen CsA systems were developed using dipalmitoylphosphocholine (DPPC) and/or cholesterol as a lipid matrix, stabilized with ethanol, with soybean oil or n-tetradecane as oil phase in emulsions, under natural pH, room and physiological temperature. Their integrity was found to be strictly dependent on the stabilizers. The highest CsA penetrability with the system containing phospholipid in the context of its interactions with lipid membranes was shown. Also, the bioavailability of CsA can be enhanced with the biopolymer antibacterial chitosan. This mini-review suggests the suitability of liposome/microemulsion as promising vehicles for CsA delivery. The most hopeful proved to be formulation with the smaller particle size facilitating absorption, but when safety is assessed, relying on just the particle size cannot be the only criteria. Reassumed, the CsA formulation stability known on the basis of the size and zeta potential measurements guarantees a decrease of the individual variations in the drug bioavailability, toxicity and minimizes rejection.

Advances in pharmacotherapy to treat kidney transplant rejection

INTRODUCTION

Current immunosuppressive combination therapy provides excellent prevention of T-cell-mediated rejection following renal transplantation; however, antibody-mediated rejection remains of high concern and accounts for a large number of long-term allograft losses. The recent development of protocol biopsies resulted in the definition of subclinical rejection (SCR), showing histologic evidence for rejection but unremarkable clinical course.

AREAS COVERED

This review describes the current knowledge and evidence of pharmacotherapy to treat kidney allograft rejections and covers SCR treatment options. Each substance is analyzed with regard to its classical indication and further discussed for the treatment of other forms of rejection.

EXPERT OPINION

Despite a lack of randomized trials, early acute T-cell-mediated rejection can be treated effectively in most cases without graft loss. The necessity to treat SCR is currently unclear. Due to a lack of effective therapies, new treatment approaches for antibody-mediated rejection are an urgent medical need to improve long-term outcomes. Future research should aim to better define pathophysiology and histology, stratify risk, and develop rational treatment strategies from randomized controlled trials, in order to establish the value of novel therapies in the arsenal of rejection pharmacotherapy. However, the effective prevention of rejection with minimal side effects still remains the goal in immunosuppression.

Is it ethical to prescribe generic immunosuppressive drugs to renal transplant patients?

PURPOSE OF THE REVIEW

This review was conducted to determine the ethical acceptability of prescribing generic immunosuppressive drugs to renal transplant patients.

SOURCES OF INFORMATION

The literature search was conducted using Pubmed and Google Scholar.

FINDINGS

The use of generic immunosuppressive drugs (ISDs) in transplantation is a controversial topic. There is a consensus among transplant societies that clinical data is lacking and that caution should be exercised. The reluctance to use generic ISDs in organ transplantation is partly related to the fact that most are "critical dose drugs", and that either low dosing or overdosing could have serious adverse consequences for both patients and society (i.e., the loss of scarce organs). In this paper, we examine the various ethical issues involved such as distributive justice, physician duties, risks versus benefits, conflict of interest, informed consent, and logistical and economic issues.

LIMITATIONS

Our analysis was limited by the paucity of clinical data on generic ISDs and the absence of health economics studies to quantify the benefits of prescribing generic ISDs.

IMPLICATIONS

Our study led us to conclude that it would be ethical to prescribe generic ISDs provided certain conditions were met. These include regulatory safeguards to minimize the risks of substitution; education of patients; and further clinical and health economics studies to better inform clinicians, patients and society of the risks and costs related to drug substitution.

Safety and efficacy of generic cyclosporine arpimune in Filipino low-risk primary kidney transplant recipients

BACKGROUND

In the Philippines, maintenance of immunosuppression may not always be affordable, leading to acute rejection and graft loss. The availability of the generic cyclosporine Arpimune could be economically beneficial, but its safety and efficacy should be established.

METHODS

This prospective cohort study enrolled 30 renal transplant patients who received Arpimune with mycophenolate/prednisone. Their results were compared up to 6 months with 30 matched control patients who received Neoral during the same period. Areas under the receiver operating characteristic curves (AUC) after intake of Arpimune and therapeutic drug monitoring using cyclosporine levels 2 hours after each dose were done. Pearson correlation was performed to determine linearity of relationship between the generic cyclosporine concentrations and AUC 0-4. Chi-square test was used in obtaining cyclosporine Arpimune concentrations.

RESULTS

The abbreviated concentration AUC of Arpimune was similar to that of Neoral, and the 2-hour sampling point (r = 0.813; P < .001) showed the best correlation. Calculated creatinine clearance (mL/min) versus Neoral was 71.36 ± 13 versus 68.03 ± 16.6 (P = .61) at 1 month, 70.4 ± 14.8 versus 64.2 ± 11.4 (P = .12) at 3 months, and 74.02 ± 15.8 versus 62.03 ± 12.1 (P = .002) at 6 months. Two Arpimune versus 4 Neoral patients (P = .67) developed biopsy-proven acute rejection. One septic death occurred in the Arpimune group. Graft survival was 100% in both groups. Hyperlipidemia was the most frequent side effect for both.

CONCLUSIONS

The AUC of Arpimune was similar to that of Neoral. Use of the generic cyclosporine Arpimune provided effective immunosuppression in the 6 months after transplantation. Renal allograft function was similar to that of Neoral, with minimal rates of acute rejection and adverse events.

Healthcare costs in renal transplant recipients using branded versus generic ciclosporin

BACKGROUND

Generic ciclosporin A modified (CsA) does not have an equivalent pharmacokinetic profile to branded CsA in some transplant populations, potentially leading to negative clinical consequences and increased long-term costs.

OBJECTIVE

To assess direct healthcare costs for de novo renal transplant recipients in the US receiving branded versus generic CsA in the first month after transplantation.

METHODS

Administrative claims data from eight private US health plans were linked to the Organ Procurement and Transplantation Network data. A total of 227 renal transplant cases between 1996 and 2004 were included: 183 were dispensed branded CsA and 44 received generic CsA. Log transformed multiple linear regression was used to model total first-year healthcare costs after the initial CsA claim, controlling for both patient demographics and clinical characteristics and clustering at the transplant centre level.

RESULTS

After controlling for patient factors and pre-CsA costs, total healthcare costs were significantly higher (p = 0.04) for patients receiving generic CsA versus branded CsA. The main driver for the difference was the cost associated with immunosuppressants other than CsA (p = 0.01).

CONCLUSION

Despite initial perceived cost savings associated with generic CsA, de novo renal transplant recipients incurred greater total healthcare costs than those treated with branded CsA. Patients receiving generic CsA may need higher doses or other immunosuppressants to maintain the transplanted kidney than patients receiving branded CsA. Providers and payers need to be aware of potential differences in total healthcare costs between formulations of bioequivalent critical-dose drugs to make the best choice for patient care.

Cyclosporine and psoriasis: 2008 National Psoriasis Foundation Consensus Conference

BACKGROUND

Cyclosporine is a valuable option for the treatment of psoriasis. This report summarizes studies regarding the use of cyclosporine since the last guidelines were published in 1998.

OBJECTIVE

A task force of the National Psoriasis Foundation Medical Board was convened to evaluate treatment options. Our aim was to achieve a consensus on new updated guidelines for the use of cyclosporine in the treatment of psoriasis.

METHODS

Reports in the literature were reviewed regarding cyclosporine therapy.

LIMITATIONS

There are few evidence-based studies on the treatment of psoriasis with cyclosporine.

RESULTS

A consensus was achieved on the use of cyclosporine in psoriasis including specific recommendations on dosing, monitoring, and use of cyclosporine in special situations. The consensus received approval from members of the National Psoriasis Foundation Medical Board.

CONCLUSIONS

Cyclosporine is a safe and effective drug for the treatment of psoriasis. It has a particularly useful role in managing psoriatic crises, treating psoriasis unresponsive to other modalities, bridging to other therapies, and treating psoriasis within a rotational scheme of other medications. Appropriate patient selection and monitoring will significantly decrease the risks of side effects.

Generics: need for clinical concern?

The market of generic drugs is in continuous development in all countries, including Belgium. Their low cost explains their success in western and developed countries. However, clinical concerns have been raised when generics are used. Indeed, various studies suggest that generic substitution can be associated with reduced efficacy or (and) increased side-effects, particularly with drugs used in severe diseases or pathological states such as epilepsy, cardiac arrhythmia, prevention of graft-rejection, ... The generic drugs must have systemic bioavailability similar to that of the original drug. Thus, they have supposed similar therapeutic bioequivalence. However, similar pharmacokinetics does not imply identical therapeutic activity, particularly with drugs having narrow therapeutic indices such as anti-epileptics, anti-arrythmics ... In this case, switchability rather than prescribability may cause problems. Low pharmaceutical quality is more frequent when drugs are produced in certain countries, in some cases causing a real concern when activity and safety are considered.

Oral cyclosporine A--the current picture of its liposomal and other delivery systems

The discovery of cyclosporine A was a milestone in organ transplantation and the treatment of autoimmune diseases. However, developing an efficient oral delivery system for this drug is complicated by its poor biopharmaceutical characteristics (low solubility and permeability) and the need to carefully monitor its levels in the blood. Current research is exploring various approaches, including those based on emulsions, microspheres, nanoparticles, and liposomes. Although progress has been made, none of the formulations is flawless. This review is a brief description of the main pharmaceutical systems and devices that have been described for the oral delivery of cyclosporine A in the context of the physicochemical properties of the drug and the character of its interactions with lipid membranes.

Physiochemical properties of generic formulations of tacrolimus in Mexico

Tacrolimus is an important immunosuppressive agent used to prevent allograft rejection after transplantation. Tacrolimus has a narrow therapeutic index; therefore, it is essential that the physicochemical properties of generic formulations be identical to the brand-name formulation, Prograf. In this study, the physicochemical properties of generic tacrolimus formulations were compared with Prograf. The drug dissolution profiles of generic formulations of tacrolimus were different from that of Prograf. Tacrobell and T-Inmun exhibited faster dissolution than Prograf, and Tenacrine, Framebin, and Talgraf showed slower and incomplete drug dissolution, releasing 24% to 51% of tacrolimus within 2 hours. Generic formulations of tacrolimus demonstrated decreased solubility compared with Prograf. The solubility of Prograf was 35.7 microg/mL at 2 hours and 29.5 microg/mL at 24 hours. The solubility of Tenacrine, Framebin, and Talgraf at 2 hours was 5.5, 12.6, and 7.8 microg/mL, respectively, and the solubility decreased to 0.5, 2.3, and 2.1 microg/mL, respectively, at 24 hours. Whereas Prograf demonstrated content uniformity, the content of the generic tacrolimus formulations varied widely. The standard deviation of content for Tenacrine, Tacrobell, and T-Inmun were high at 29.3, 6.9, and 5.6, respectively. Furthermore, the mean percentage of labeled amount of T-Inmun was 84.2% with a relative standard deviation of 6.7% (minimum value; 72.7%; maximum value; 100.7%). These results indicate that generic formulations of tacrolimus tested in this study are not bioequivalent to Prograf, which suggests that their use may be of potential risk to transplant patients.

PEG-b-PPS diblock copolymer aggregates for hydrophobic drug solubilization and release: cyclosporin A as an example

Micelles formed from amphiphilic block copolymers have been explored in recent years as carriers for hydrophobic drugs. In an aqueous environment, the hydrophobic blocks form the core of the micelle, which can host lipophilic drugs, while the hydrophilic blocks form the corona or outer shell and stabilize the interface between the hydrophobic core and the external medium. In the present work, mesophase behavior and drug encapsulation were explored in the AB block copolymeric amphiphile composed of poly(ethylene glycol) (PEG) as a hydrophile and poly(propylene sulfide) PPS as a hydrophobe, using the immunosuppressive drug cyclosporin A (CsA) as an example of a highly hydrophobic drug. Block copolymers with a degree of polymerization of 44 on the PEG and of 10, 20 and 40 on the PPS respectively (abbreviated as PEG44-b-PPS10, PEG44-b-PPS20, PEG44-b-PPS40) were synthesized and characterized. Drug-loaded polymeric micelles were obtained by the cosolvent displacement method as well as the remarkably simple method of dispersing the warm polymer melt, with drug dissolved therein, in warm water. Effective drug solubility up to 2 mg/mL in aqueous media was facilitated by the PEG- b-PPS micelles, with loading levels up to 19% w/w being achieved. Release was burst-free and sustained over periods of 9-12 days. These micelles demonstrate interesting solubilization characteristics, due to the low glass transition temperature, highly hydrophobic nature, and good solvent properties of the PPS block.

Neoimmun versus Neoral: a bioequivalence study in healthy volunteers and influence of a fat-rich meal on the bioavailability of Neoimmun

In two crossover studies with 12 (6 males/6 females) healthy young volunteers each, we compared the bioavailability of Neoimmun capsules with the microemulsion Neoral and the influence of a fat-rich breakfast on the bioavailability of Neoimmun. Each volunteer received a single dose of 200 mg cyclosporine A in each period. Blood samples were taken up to 24 h and analysed for cyclosporine A by high-performance liquid chromatography (HPLC) and photometric detection. The pharmacokinetic parameters were determined by non-compartmental analysis. The treatments were tested for bioequivalence and significant differences. The bioavailability of Neoimmun was significantly lower compared to Neoral, albeit Neoimmun met the bioequivalence criterion (90% confidence interval of AUC 0.80-0.94) or missed the criterion only marginally (90% confidence interval of c (max) 0.75-0.91). The bioavailability of Neoimmun as determined by area under the blood concentration-time curve (AUC) increased by nearly 20% after a fat-rich breakfast. However, mean peak concentrations after food were only higher in male subjects, whereas mean peak concentrations in female subjects were lower compared to fasting administration. In conclusion, our data show that Neoimmun exhibits a lower bioavailability than the microemulsion Neoral and that food has a significant but variable and sex-dependent impact on the bioavailability of Neoimmun capsules.

Clinical evaluation of efficacy and safety of cyclosporine (Imusporin) in renal transplant patients with stable graft function maintained on neoral or bioral

Objective:

Previous pharmacokinetic studies have demonstrated bioequivalence of Imusporin (microemulsion preparation of cyclosporine, Cipla) to the innovator product Neoral (Novartis, Switzerland). This study was done to evaluate the clinical efficacy and safety of Imusporin in patients who have already undergone renal transplant and have stable graft function maintained on cyclosporine preparation other than Imusporin.

Materials and Methods:

Twenty-two renal allograft recipients (mean age of 31.77 years, range 18-53 years), with stable graft function, previously on Neoral or Bioral were switched over to Imusporin after recording their relevant baseline clinical and biochemical parameters. These were repeated on 1, 4, 7, 15, 30 and 90 days after the start of therapy. Change in dosage required to maintain C2 levels at each visit were analyzed by paired sample t-test. Safety of the drug was assessed by the type and severity of adverse events developed during the therapy. Cost analysis was done assuming an average maintenance immunosuppression dose of 150 mg/day of cyclosporine.

Results:

Twenty-one patients completed the study. One patient was lost to follow-up. Mean C2 value before switchover was 894 ± 208 ng/ml, which was not significantly different from the mean values of C2 after switchover therapy (P>0.30). Change in dosage required to maintain C2 levels was not significantly different from the baseline dose of 2.34 mg/ kg body weight (P>0.1). No patient developed graft rejection after switchover therapy at a median follow-up of 16 months (14-18 months). Mean baseline SCr was similar to SCr at day 90 (1.38 vs. 1.37 mg/dl, P=0.930). No severe adverse events were reported. Mild side-effects included headache (4), somnolence (2), dry mouth (5) and generalized fatigue (6). Use of Imusporin (Cipla, India) results in an annual savings of Rs. 19892 over Neoral (Novartis, Switzerland) and Rs. 2263 over Bioral (Panacea Biotech, India).

Conclusions:

Imusporin is clinically as safe and efficacious as other cyclosporine preparations available while significantly reducing the cost of treatment.

Bioequivalence of enteric-coated mycophenolate sodium and mycophenolate mofetil: a meta-analysis of three studies in stable renal transplant recipients

BACKGROUND

Mycophenolic acid (MPA) is an inhibitor of lymphocyte proliferation and is well established as an immunosuppressive agent in solid organ transplantation. The initial formulation of the drug was a prodrug formulation, mycophenolate mofetil (MMF, Cellcept), which is well absorbed and rapidly converted to mycophenolate in plasma. However, the use of MMF is associated with adverse gastrointestinal events, which can lead to withdrawal of therapy. In an effort to reduce the gastrointestinal effects of MMF, an enteric-coated formulation of the drug was developed, based on the sodium salt of MPA (EC-MPS, Myfortic).

METHODS

Although bioequivalence has been demonstrated in an individual study in maintenance kidney transplant patients, this manuscript documents bioequivalence in a much larger data set of 82 patients by a meta-analysis of data from clinical trials.

RESULTS

The results confirm the bioequivalence of EC-MPS and MMF for both mycophenolate and metabolite exposure, and for maximum plasma mycophenolate concentrations, across three studies. The 90% confidence interval of the ratio of EC-MPS to MMF for mycophenolate plasma AUC in the 82 patients was 101.1 to 114.5% and for Cmax was 83.0% to 112.7%.

CONCLUSION

These findings provide reassurance to transplant professionals and patients that, when choosing between EC-MPS and MMF, they are choosing between formulations that give equivalent mycophenolate exposure.

Comparative bioavailability of the microemulsion formulation of cyclosporine (Neoral) with a generic dispersion formulation (Cicloral) in young healthy male volunteers

The aim of this study was to compare the bioavailability of cyclosporine (CyA) from the generic dispersion formulation Cicloral (CIC) with the microemulsion formulation Neoral (NEO) and the original Sandimmune (SIM) capsules after single doses of 100, 300, or 600 mg of drug, respectively. The study was performed according to an open 3-period cross-over design with 12 young healthy male volunteers for each dosage. The concentrations of CyA and its main metabolites were determined by high performance liquid chromatography in whole blood and urine up to 48 hours postdosing. Peak concentrations and area under the time-concentration curve were greater for the NEO and CIC formulations compared with SIM, and the mean bioavailability of CIC was significantly (P<0.05) lower compared with NEO. The bioavailability of SIM compared with NEO was 54% to 71%, in agreement with previous results. Bioequivalence was not demonstrated between CIC (test) and NEO (reference) as the 90% confidence intervals were outside the 80% to 125% guidelines based on log-transformed AUCs, and were 75.2% to 87.7% at 100 mg, 79.2% to 91.8% at 300 mg, and 76.6% to 94.5% at 600 mg doses. The respective values for Cmax were 78.9% to 94.6%, 80.7% to 95.0%, and 71.4% to 84.1%. A good correlation was demonstrated between the urinary recovery of CyA and the AUC4. Therefore, the urinary recovery of CyA may be helpful as a surrogate parameter for the systemic exposure of patients to CyA. Whereas the relative amount of hydroxylated metabolites (AM1, AM9, AM1c) was similar for all formulations and doses, the urinary recovery of the N-demethylated metabolite AM4N decreased with increasing dose indicating saturable metabolism. No relationship could be demonstrated between CYP3A activity using dextromethorphan as a probe for the metabolic clearance of CyA.

Comparison of Generic Cyclosporine Microemulsion versus Neoral in de Novo Renal Transplant Recipients Managed By 2-Hour Postdose Monitoring

INTRODUCTION

The bioequivalence of generic formulations is established by measuring pharmacokinetic parameters in healthy volunteers. Cyclosporine (CsA) absorption and exposure is known to differ between healthy volunteers and transplant recipients. Therefore bioequivalence testing may be inadequate to ensure therapeutic equivalence. We sought to compare the efficacy of generic cyclosporine (ArpimuneME, RPG Life Sciences) versus Sandimmune Neoral in de novo renal transplant recipients.

METHODS

A prospective single-center, open-label study enrolled 20 de novo renal transplant patients (group 1: mean age 30.55 +/- 9.81 years, M:F 19:1, mean donor age 43.4 +/- 10.8). All patients received ArpimuneME along with azathioprine and prednisolone. The results were compared with 17 matched controls (group 2: mean age 28.1 +/- 9.5 years, M:F 13:4, mean donor age 47.8 +/- 6.8) who received Neoral and were transplanted during the same period. C(2) levels were monitored by the cloned enzyme donor immunoassay (CEDIA).

RESULTS

Patient and graft survivals were 100% and 100% and 100% and 92.8% in groups 1 and 2, respectively (P = NS). Six patients (30%) experienced rejection in group 1 as compared eight patients (47.1%) in group 2. Mean CsA levels (ng/mL) during the first month were 1419.1 +/- 213.6 and 1460.5 +/- 290.7 and at 3 months, 1296.3 +/- 227.8 and 1342.4 +/- 303.4 in the two groups, respectively (P = NS). The mean serum creatinine levels (mg%) in group 1 and group 2 were 1.6 +/- 0.8 and 2.0 +/- 1.4 at discharge and 1.5 +/- 0.4 and 1.5 +/- 0.8 at 6 months, respectively (P = NS).

CONCLUSION

Use of a generic microemulsion form of CsA provided safe and effective immunosuppression compared with Sandimmune Neoral when drug monitoring was performed by C(2) levels.

Cyclosporine Formulation and Kaposi’s Sarcoma after Renal Transplantation

BACKGROUND

Transplantation enhances the risk of malignancies, due to the chronic use of antirejection medication. In the case of Kaposi's sarcoma (KS) the permissive effect of immunosuppression has been extensively studied, and cyclosporine (CsA) appears to play a key role. Here we have compared the incidence of KS in transplant patients receiving Neoral or Sandimmune as a part of their immunosuppressive therapy.

METHODS

In all, 668 kidney transplant recipient followed at our Nephrology Unit from 1970 to 2003 entered this retrospective analysis; 300 were on CsA Sandimmune-based and 308 on CsA Neoral-based therapy. The primary endpoint was the occurrence of KS.

RESULTS

KS was diagnosed in 20 out of 608 patients given CsA with an incidence rate of 4.7 per 1000 patients per year. No episodes of KS was found in the preCsA era. Among patients on CsA, those treated with Neoral had fourfold higher incidence rate of KS than in the Sandimmune group (10.7 vs. 2.3 per 1000 patients per year). Kaplan-Meier analysis shows that patients on Neoral had lower cumulative KS-free probability than those on Sandimmune. Cox's analysis documented that Neoral was a positive predictor of KS development as compared to Sandimmune (hazard ratio: 2.237). Among patients on Neoral, those who developed KS had higher daily exposure to the drug assessed by pharmacokinetic studies.

CONCLUSIONS

In recipients of kidney transplant CsA Neoral increases the risk of KS as compared to the Sandimmune formulation, possibly due to enhanced drug bioavailability and ultimately patients daily CsA exposure.