Initial dosage optimisation of cyclosporine in Chinese paediatric patients undergoing allogeneic haematopoietic stem cell transplantation based on population pharmacokinetics: a retrospective study.

OBJECTIVE: Improved understanding of cyclosporine A (CsA) pharmacokinetics in children undergoing allogeneic haematopoietic stem cell transplantation (allo-HSCT) is crucial for effective prevention of acute graft-versus-host disease and medication safety. The aim of this study was to establish a population pharmacokinetic (Pop-PK) model that could be used for individualised therapy to paediatric patients undergoing allo-HSCT in China. DESIGN, SETTING AND PARTICIPANTS: A retrospective analysis of 251 paediatric HSCT patients who received CsA intravenously in the early post transplantation period at Women and Children's Medical Center in Guangzhou was conducted. ANALYSIS MEASURES: The model building dataset from 176 children was used to develop and analyse the CsA Pop-Pk model by using the nonlinear mixed effect model method. The basic information was collected by the electronic medical record system. Genotype was analysed by matrix-assisted time-of-flight mass spectrometry. The stability and predictability of the final model were verified internally, and a validation dataset of 75 children was used for external validation. Monte Carlo simulation is used to adjust and optimise the initial dose of CsA in paediatric allo-HSCT patients. RESULTS: The typical values for clearance (CL) and volume of distribution ([Formula: see text]) were 14.47 L/hour and 2033.53 L, respectively. The body weight and haematocrit were identified as significant variables for V, while only body weight had an impact on CL. The simulation based on the final model suggests that paediatrics with HSCT required an appropriate intravenous dose of 5 mg/kg/day to reach the therapeutic trough concentration. CONCLUSIONS: The CsA Pop-PK model established in this study can quantitatively describe the factors influencing pharmacokinetic parameters and precisely predict the intrinsic exposure to CsA in children. In addition, our dosage simulation results can provide evidence for the personalised medications TRIAL REGISTRATION NUMBER: ChiCTR2000040561.

Ciclosporin A Cationic Emulsion 0.1% for the Management of Dry Eye Disease: Facts That Matter for Eye-Care Providers.

Dry eye disease (DED) is a chronic inflammatory disease of the ocular surface requiring long-term therapy. Severe forms of DED generally do not respond to tear substitutes alone or combined, and often require treatment with topical anti-inflammatory agents to break the vicious circle of inflammation. This review summarises data from randomised controlled trials and real-world evidence on the efficacy and safety of ciclosporin A 0.1% cationic emulsion (Ikervis®) for the management of DED. Improvements in clinical signs and symptoms were reported from as early as 4 weeks after treatment initiation, although it can take a few months to reach the full benefits. Treatment periods of up to 12 months provide sustained benefit to patients. In the most responsive patients, treatment discontinuation is possible with no further substantial relapse over 12 months in over 65% of patients. Transient local ocular effects are the most commonly reported adverse events.

Transition from Amorphous Cyclosporin A Nanoparticles to Size-Reduced Stable Nanocrystals in a Poloxamer 407 Solution.

Amorphous drug nanoparticles usually exhibit low storage stability. A comprehensive understanding of the molecular states and physicochemical properties of the product is indispensable for designing stable formulations. In the present study, an amorphous cyclosporin A (CyA) nanosuspension with a mean particle size of approximately 370 nm was prepared by wet bead milling with poloxamer 407 (P407). Interestingly, the prepared amorphous CyA nanoparticles were transformed into uniform CyA nanocrystals with a reduced mean particle size of approximately 200 nm during storage at 25 °C. The CyA nanocrystals were stably maintained for at least 1 month. The particle morphologies and molecular structures of the CyA nanosuspensions before and after storage were thoroughly characterized by cryogenic transmission electron microscopy and magic-angle spinning nuclear magnetic resonance spectroscopy, respectively. They revealed that the freshly prepared amorphous CyA nanoparticles (∼370 nm) were secondary particles composed of aggregated primary particles with an estimated size of 50 nm. A portion of P407 was found to be entrapped at the gaps between the primary particles due to aggregation, while most of P407 was dissolved in the solution either adsorbing at the solid/liquid interface or forming polymeric micelles. The entrapped P407 is considered to play an important role in the destabilization of the amorphous CyA nanoparticles. The resultant CyA nanocrystals (∼200 nm) were uniform single crystals of Form 2 hydrate and showed corner-truncated bipyramidal features. Owing to the narrow particle size distribution of the CyA nanocrystals, the rate of Ostwald ripening was slow, giving long-term stability to the CyA nanocrystals. This study provides new insights into the destabilization mechanism of amorphous drug nanoparticles.

A Proposed Approach for the Determination of the Bioequivalence Acceptance Range for Narrow Therapeutic Index Drugs in the European Union.

The current regulatory criterion for bioequivalence of narrow therapeutic index (NTI) drugs in the European Union requires that the 90% confidence interval for the ratio of the population geometric means of the test product compared with the reference for area under the plasma concentration-time curve (AUC), and in certain cases maximum plasma drug concentration (Cmax ), to be included within the tighter acceptance range of 90.00-111.11%. As a consequence, sponsors need to recruit a higher number of subjects to demonstrate bioequivalence and this may be seen as increasing the burden for the development of generics. This "one-size-fits-all" criterion is particularly questionable when the within-subject variability of the reference product is moderate to high. As an alternative, we propose a further refined statistical approach where the acceptance range is narrowed based on the within-subject variability of the reference product of the NTI drug, similar to the one used for widening the standard 80.00-125.00% acceptance range for highly variable drugs. The 80.00-125.00% acceptance range is narrowed, only if the within-subject variability is lower than 30%, down to the current NTI acceptance range of 90.00-111.11% when the within-subject variability is 13.93% or lower. Examples within the current European Medicines Agency list of NTI drugs show a considerable reduction in required sample size for drugs like tacrolimus and colchicine, where the predicted within-subject variability is 20-30%. In these cases, this approach is less sample size demanding without any expected increase in the therapeutic risks, since patients treated with reference products with moderate to high within-subject variability are frequently exposed to bioavailability differences larger than 10%.

A comprehensive review on possibilities of treating psoriasis using dermal cyclosporine.

Psoriasis is an autoimmune, chronic proliferative, inflammatory skin disease with high comorbidity. Psoriasis is not a curable disease; it can only be managed. Cyclosporine A (CyA) is one of the FDA-approved immunosuppressant drug used in severe Psoriasis. Till date only oral route is used for its administration. Administration of CyA by this route causes serious side effects such as hypertension and renal toxicity. Due to these side effects, a number of researches have been done and taking place in the current times for the dermal delivery of CyA for the management of psoriasis. Dermal delivery of CyA is not an easy task because of its physiochemical properties like high molecular weight, lipophilicity and resistance offered by stratum corneum (SC). Because of the above problems in the dermal delivery a number of new approaches such as nanolipid carriers, microemulsion, liposomes, niosomes etc. are explored. To those deep findings for psoriasis management with dermal delivery of CyA have not been discussed. This comprehensive review includes all the studies, advancements and their critical findings which took place in the recent times for the dermal delivery of CyA and along with the suitable modification needed for the efficient dermal delivery of CyA are also suggested.

Comparison of the clinical effects of two different doses (0. 05% and 0. 1%) of topical cyclosporine A in dry eyes with meibomian gland dysfunction / Comparação de efeitos clínicos de duas doses diferentes (0, 05% e 0, 1%) de ciclosporina A tópica em olhos secos com disfunção da glândula tarsal

ABSTRACT Objective: To compare the clinical efficacy of two different doses of topical cyclosporine A used in addition to artificial tears in the treatment of patients with meibomian dysfunction and secondary dry eye. Methods: Fifty patients aged 18 to 40 years, who presented to our clinic between June 2020 and June 2021 were included in our study. Patients were divided into two groups as Group A (topical cyclosporine A 0.05%) and Group B (topical cyclosporine A 0.1%). All the patients underwent a detailed ophthalmological examination, basal Ocular Surface Disease Index measurement, and Schirmer 1 and tear break-up time tests at all visits. Results: The mean age was 32±7.1 years in Group A and 30.7±8.5 years in Group B. In Group A, there were 15 women and ten men, and Group B consisted of 14 women and 11 men. There was no difference between the groups in terms of age and gender distribution (p>0.05). Schirmer 1 and tear break-up time results and Ocular Surface Disease Index score also did not significantly differ between the groups (p>0.05). Conclusion: Cyclosporine A 0.05% and 0.1% eye drops were both seen to be effective in managing dry eye disease in patients with meibomian gland dysfunction.

RESUMO Objetivo: Comparar a eficácia clínica de duas doses diferentes de ciclosporina A tópica utilizada além da lágrima artificial no tratamento de pacientes com disfunção da glândula tarsal e olho seco secundário. Métodos: No estudo, foram incluídos 50 pacientes com idades entre 18 e 40 anos, que se apresentaram em nossa clínica entre junho de 2020 e junho de 2021. Os pacientes foram divididos em dois grupos: Grupo A (ciclosporina A 0,05% tópica) e Grupo B (ciclosporina A 0,1% tópica). Todos os pacientes foram submetidos a um exame oftalmológico detalhado, medição basal do Índice de Doença da Superfície Ocular, e testes de Schirmer 1 e de tempo de ruptura em todas as visitas. Resultados: A idade média foi de 32±7,1 anos no Grupo A e 30,7±8,5 anos no Grupo B. No Grupo A, havia 15 mulheres e dez homens, e o Grupo B consistia de 14 mulheres e 11 homens. Não havia diferença significativa entre os grupos em termos de distribuição por idade e gênero (p>0,05). Os resultados do Schirmer 1 e do tempo de ruptura e do Índice de Doenças da Superfície Ocular também não apresentaram diferença significativa entre os grupos (p>0,05). Conclusão: Observou-se que os colírios de ciclosporina A 0,05% e 0,1% são eficazes no tratamento da síndrome do olho seco em pacientes com disfunção da glândula tarsal.

Biochemical and histopathological evaluations of chronic renal failure rats treated with pluripotent human stem cells

Abstract Regeneration of damaged kidney cells using stem cells is the current research approach in the treatment of chronic renal failure (CRF). In the present study, the histopathological and biochemical techniques were used to evaluate stem cells' (SCs) role in treatment of CRF. Sixty-four rats were divided into eight groups. Group I (GI): rats were injected with doxorubicin (15 mg/kg) to initiate CRF. GII-GVII: rats were injected with doxorubicin and treated with SCs (1x106 MSCs or/and 2x104 HSCs/rat) with/without growth factors extract (200 µL/rat) and/or immunosuppressor (cyclosporine A, 5 mg/kg/day). GVIII: rats treated with PBS (100 µL/kg/day). Levels of creatinine, urea and uric acid were increased in rats sera after injection with doxorubicin, while blood electrolyte levels of Na, K, P and Mg were decreased. Also, histopathological abnormalities such as hyalinized blood vessels, degenerated hyalinized glomerulus tubules and cell debris in the lumen and degeneration of renal tissues were observed in these rats. After treatment with SCs, all these parameters restore their normal values with regeneration of the damaged cells as demonstrated in histopathology of the treated groups. It can be concluded that, the use of SCs in treatment of kidney diseases is a promising approach and needs more efforts.

Clinical study on the application of dexamethasone and cyclosporine/dimethyl sulfoxide combination eye drops in the initial therapy of chronic superficial keratitis in dogs.

PURPOSE: To assess the initial therapy of chronic superficial keratitis (CSK) in dogs with the use of dexamethasone and cyclosporine/ dimethyl sulfoxide combination eye drops. METHODS: The study was conducted on 41 dogs - 16 males and 25 females, aged 2 to 9 years, diagnosed with CSK. The disease was treated with two kinds of eye drops containing 0.1% dexamethasone and 0.75% cyclosporine in combination with 30% DMSO, administered three times a day. Prior to the treatment and after 5 weeks of therapy, depigmentation of the third eyelid margin, corneal neovascularization and pigmentation were assessed. The percentage of the corneal surface afflicted with inflammatory processes was calculated with the use of IsoCalc.com's Get Area software for CorelDRAW12. RESULTS: The administered therapy resulted in a significant decrease in the mean number of quadrants affected by corneal neovascularization in the right eye from 2.63 prior to treatment to 0.24 after treatment (p⟨0.001), and the left eye from 2.66 to 0.59 (p⟨0.001), respectively. Mean corneal surface afflicted with inflammatory processes was statistically significantly reduced from 53.5% to 26.3% (p⟨0.001) in the case of right corneas, and from 54.5% to 30.2% (p⟨0.001) in the case of left corneas. Of 77 corneas diagnosed with pigmentation, pigmentation reduction was observed in 54 and pigmentation increase in 27. CONCLUSIONS: Using dexamethasone and cyclosporine/DMSO combination eye drops proved to be a viable initial therapy against CSK, which facilitates reduction of inflammatory processes and neovascularization atrophy, but in many cases does not inhibit the progress of pigmentation.

Cyclosporine A Nanosuspensions for Ophthalmic Delivery: A Comparative Study between Cationic Nanoparticles and Drug-Core Mucus Penetrating Nanoparticles.

The effect of mucin on ocular bioavailability depends on the extent to which it acts as a barrier or retention site. Mucus penetrating particles (MPPs) can evade the mucus entrapment and associated rapid clearance, but cationic nanoparticles have high adhesion to the mucosa. Both formulations can prolong the drug residence time on the surface of the eyes. The purpose of this work is to compare the effects of mucoadhesion of cationic nanoparticles and mucous permeability of MPPs on ocular bioavailability. Cationic nanosuspensions and drug-core MPP nanosuspensions were developed using the anti-solvent precipitation method. The results of X-ray diffraction revealed that CsA was amorphous. In vitro mucoadhesion evaluation demonstrated that cationic nanosuspensions enhanced the interaction with pig mucin about 5.0-6.0 fold compared to drug-core MPP nanosuspensions. A mucus permeation study by the transwell diffusion system showed that the Papp values of drug-core MPP nanosuspensions were 5.0-10.0 times higher than those of cationic nanosuspensions. In vivo ocular bioavailability evaluation of those CsA formulations was conducted in rabbits using a conventional nanosuspension as a comparison. The CsA concentrations in the cornea following the administration of a cationic nanosuspension and a drug-core MPP nanosuspension were 13,641.10 ng/g and 11,436.07 ng/g, respectively, significantly higher than that of the conventional nanosuspension (8310.762 ng/g). The results showed that both the cationic and MPP nanosuspensions were able to deliver CsA to anterior ocular tissues in effective therapeutic concentrations (10-20 µg/g) with topical drop instillation. The cationic nanosuspension could achieve relatively higher bioavailability than the MPP nanosuspension. The cationic nanosuspension would be a promising ocular drug delivery system.

Factors Affecting Time-Varying Clearance of Cyclosporine in Adult Renal Transplant Recipients: A Population Pharmacokinetic Perspective.

AIM: The pharmacokinetic (PK) properties of cyclosporine (CsA) in renal transplant recipients are patient- and time-dependent. Knowledge of this time-related variability is necessary to maintain or achieve CsA target exposure. Here, we aimed to identify factors explaining variabilities in CsA PK properties and characterize time-varying clearance (CL/F) by performing a comprehensive analysis of CsA PK factors using population PK (popPK) modeling of long-term follow-up data from our institution. METHODS: In total, 3674 whole-blood CsA concentrations from 183 patients who underwent initial renal transplantation were analyzed using nonlinear mixed-effects modeling. The effects of potential covariates were selected according to a previous study and well-accepted theoretical mechanisms. Model-informed individualized therapeutic regimens were also evaluated. RESULTS: A two-compartment model adequately described the data and the estimated mean CsA CL/F was 32.6 L h-1 (relative standard error: 5%). Allometrically scaled body size, hematocrit (HCT) level, CGC haplotype carrier status, and postoperative time may contribute to CsA PK variability. The CsA bioavailability in patients receiving a prednisolone dose (PD) of 80 mg was 20.6% lower than that in patients receiving 20 mg. A significant decrease (52.6%) in CL/F was observed as the HCT increased from 10.5% to 60.5%. The CL/F of the non-CGC haplotype carrier was 14.4% lower than that of the CGC haplotype carrier at 3 months post operation. CONCLUSIONS: By monitoring body size, HCT, PD, and CGC haplotype, changes in CsA CL/F over time could be predicted. Such information could be used to optimize CsA therapy. CsA dose adjustments should be considered in different postoperative periods.

Influence of TGFB1 and CTLA4 polymorphisms on calcineurin inhibitors dose and risk of acute rejection in renal transplantation.

Organ transplant is often the treatment of choice as it extends and improves patient life. Immunosuppressive treatment, which prevents acute rejection of the organ, is used in transplant patients to prevent the loss of transplant. The aim of the study was to determine the impact of the CTLA4 (+49A>G, rs231775) and the TGF-ß1 (-800G>A, rs1800468) polymorphisms on the therapeutic effect of immunosuppressive drugs (cyclosporine-CsA, tacrolimus-TAC) and the risk of acute rejection in renal transplant patients. The analysis of the CTLA4 +49A>G and the TGF-ß1 -800G>A polymorphisms was carried out in 392 patients after kidney transplant using real-time PCR. The CTLA4 +49A>G polymorphism did not affect CsA or TAC dose, ratio of drug concentration to dose (C/D), and blood concentrations. As for the TGF-ß1 -800G>A polymorphism, patients with the GA genotype required lower TAC doses compared to the GG genotype (TAC 12 h: 3.63 mg vs 5.3 mg, TAC 24 h: 2.38 mg vs 3.29 mg). Comparing the C/D ratio in both groups (TAC 12 h and TAC 24 h), higher C/D ratio was observed in patients with the GA genotype. These results indicate that patients with the A allele require slightly lower doses of TAC. The results suggest that the TGF-ß1 -800 G>A polymorphism may influence the TAC dose, while the +49A>G polymorphism of the CTLA4 gene does not correlate with the dose of CsA or TAC. The analysis of the biochemical parameters of the renal profile showed no impact of the CTLA4 and the TGF-ß1 polymorphisms on the risk of organ rejection.

A Water-free 0.1% Cyclosporine A Solution for Treatment of Dry Eye Disease: Results of the Randomized Phase 2B/3 ESSENCE Study.

PURPOSE: To assess the efficacy, safety, and tolerability of a topical water-free cyclosporine A formulation (CyclASol 0.1% ophthalmic solution) in comparison with vehicle for the treatment of dry eye disease (DED). METHODS: Three hundred twenty-eight patients were enrolled in this prospective, 12-week, multicenter, randomized, double-masked, confirmatory, vehicle-controlled clinical study. After a 2-week run-in period, eligible DED patients were randomized 1:1 to either CyclASol 0.1% or vehicle twice daily. The primary efficacy endpoint was change from baseline in total corneal fluorescein staining (National Eye Institute scale), and the second hierarchical primary efficacy endpoint was change from baseline in the Ocular Surface Disease Index score, both at 4 weeks. Secondary efficacy and safety assessments included conjunctival lissamine green staining (Oxford scale), visual analog scales for dry eye symptoms, and adverse event. RESULTS: Treatment with CyclASol 0.1% was superior to vehicle in the primary endpoint: total corneal fluorescein staining at week 4 (Δ -0.8; 95% confidence interval, -1.3 to -0.4; P = 0.0002, analysis of covariance). This difference had already reached statistical significance after 2 weeks and was maintained throughout the study. The study did not statistically meet its second hierarchically tested primary endpoint: Ocular Surface Disease Index score (P = 0.2634). However, CyclASol 0.1% treatment showed statistically significant improvement compared with that of vehicle in the eye dryness score at week 4 (Δ -4.783; 95% confidence interval, -9.129 to -0.438; P = 0.0311). CONCLUSIONS: CyclASol 0.1% was effective in treating signs and symptoms of DED. It significantly reduced corneal and conjunctival staining and improved ocular dryness compared with vehicle. CyclASol 0.1% was safe and showed excellent tolerability.

Effect of Face Mask on Tear Film Stability in Eyes With Moderate-to-Severe Dry Eye Disease.

PURPOSE: The purpose of this study was to evaluate whether tear film stability worsens with the use of masks in patients with dry eye disease, objectively analyzing the tear film stability using noninvasive tear film breakup time (NITBUT) with and without a face mask. METHODS: A cross-sectional study including patients with moderate or severe dry eye disease was conducted. Tear stability was measured using an Oculus Keratograph 5M (Oculus, Wetzlar, Germany), which records NITBUT, both first and average NITBUT. Two measurements were taken: an initial measurement with a mask and a second measurement after 10 minutes without wearing the face mask. RESULTS: Thirty-one patients were included with a mean age of 57.6 ± 11.7 years (range 31-80) and 30 being female (97%). Mean first NITBUT with face mask was 6.2 ± 3.8 seconds (range 2.0-19.8), which increased to 7.8 ± 5.6 seconds (range 2.3-24.0) without the use of mask (P = 0.029), differences being -1.6 ± 0.7 seconds (CI 95% -3.1075 to -0.1770). Mean average NITBUT with a face mask was 12.3 ± 4.8 seconds (range 4.0-19.4) and increased to 13.8 ± 5 seconds (range 5.5-24.0) without the use of mask (P = 0.006), mean difference being -1.5 ± 0.5 seconds (CI 95% -2.5290 to -0.4458). CONCLUSIONS: Face mask use decreases tear film stability in patients with moderate-to-severe dry eye.

Enfermedad de injerto contra huésped cutánea frente a necrólisis epidérmica tóxica en un receptor de trasplante de células madre hematopoyéticas / Cutaneous graft-versus-host disease versus toxic epidermal necrolysis in a hematopoietic stem cell transplant recipient

El diagnóstico diferencial entre la enfermedad de injerto contra huésped aguda grave (estadio IV) y la necrólisis epidérmica tóxica pude resultar difícil en el contexto de un paciente trasplantado, ya que ambas tienen presentaciones clínicas similares. Sin embargo, la distinción entre ellas es fundamental porque ocasionan una gran morbimortalidad, y su manejo y pronóstico difieren. Algunas pequeñas diferencias clínicas e histopatológicas son de gran ayuda para el diagnóstico diferencial y el dermatólogo deberá reconocerlas para tomar una conducta correcta y oportuna. Se comunica el caso de un paciente que presentó ampollas y epidermólisis después del trasplante de células hematopoyéticas y en el que se planteó la dificultad diagnóstica para diferenciar entre ambas afecciones.

The differental diagnosis between severe graft-versus-host disease (stage IV) and toxic epidermal necrolysis can be difficult in the context of a transplant patient, since both conditions have similar clinical presentations. However, the distinction between these two entities is critical because they produce great morbidity and mortality and their management and prognosis differ. Some small clinical and histopathological differences are of great help for the differential diagnosis, and the dermatologist must recognize them in order to take a correct and timely conduct. We present the case of a patient who developed blisters and epidermolysis after hematopoietic cell transplantation, and in whom the diagnostic difficulty to differentiate between the two entities was raised.

Successful treatment of multiple relapsed-refractory Langerhans cell histiocytosis with cyclosporine.

Langerhans cell histiocytosis is a rare hematologic disorder and patients who fail first-line treatment have a poor prognosis, and require more intensive treatment. We present an infant diagnosed with multisystem Langerhans cell histiocytosis refractory to multimodal therapy who was successfully treated with cyclosporine. Cyclosporine might be an effective alternative drug as nonmyelosuppressive rescue therapy for multiple relapsed-refractory Langerhans cell histiocytosis that has not achieved remission with cladribine and cytarabine therapy.

Efficacy of Switching from Cyclosporine A 0.05% Anionic Emulsion to Cyclosporine A 0.1% Cationic Emulsion in Patients with Dry Eye Associated with Sjögren's Syndrome.

Purpose: To evaluate the clinical efficacy of switching from cyclosporine A (CsA) 0.05% anionic emulsion (CsA AE) to CsA 0.1% cationic emulsion (CsA CE) in patients with dry eye (DE) associated with Sjögren's syndrome (SS). Methods: Forty patients with SS-associated DE who were unresponsive to CsA AE for 6 months were enrolled. After baseline measurements, the CsA AE was switched to CsA CE. The ocular surface disease index (OSDI), Sjögren's International Collaborative Clinical Alliance (SICCA), and Schirmer's test scores and tear film breakup time (TBUT) were evaluated at baseline and 1 and 3 months after switching. Results: Two patients dropped out, and 38 were analyzed. OSDI and SICCA ocular staining scores were significantly reduced at 1 and 3 months after switching, compared with the baseline scores (all P < 0.01). Although no significant changes were noted in the corneal staining scores (CSSs), patients with higher baseline CSS (≥4) showed an improvement in the scores at 1 month (P = 0.03) and 3 months (P = 0.01) after switching. There were no significant changes in TBUT and Schirmer's test scores during the follow-up periods. Conclusions: In patients with SS-associated DE, switching from CsA AE to CsA CE was effective in improving ocular symptoms and conjunctival staining. In addition, corneal staining was decreased in patients with severe keratitis.

A Case of Shield Ulcer Due to Vernal Keratoconjunctivitis.

Corneal shield ulcer is an uncommon but serious complication of vernal keratoconjunctivitis (VKC) that can threaten visual acuity. We present a 12-year-old case with a corneal shield ulcer on the superior part of the cornea in the right eye. We learned from his history that he was treated with topical cyclosporine A (CsA) and corneal debridement was performed for the same complaints six months ago. His complaints recurred six months after ceasing topical CsA voluntarily. Topical anti-allergic and CsA treatments were commenced, we also performed corneal debridement. During his follow-ups, the corneal ulcer healed leaving a scar as opacity and neovascularization. This case highlights the role of the anti-inflammatory effect of CsA in preventing the recurrence of shield ulcers.

Oral bioavailability studies of niosomal formulations of Cyclosporine A in albino rabbits.

Cyclosporine A (CsA) is an immunosuppressant agent. Two niosomal formulations of CsA, FTS and FSB were formulated. Both formulations were studied in terms of size, polydispersity index (PDI), morphology and entrapment efficacy etc. Niosomal formulations FTS and FSB and plain aqueous dispersion were given to three assemblies of Albino rabbits (n=8 per group). CsA levels in plasma were determined at appropriate time intervals and pharmacokinetic parameters were evaluated. The percentage entrapment efficiencies of FTS and FSB were found to be 77.29 and 89.31% for respectively. Transmission electron microscopy results indicated spherical nature of niosomes. In vivo studies demonstrated that the value of Cmax for the FSB formulation was 1968.419 ng/ml and it was 1498.951 ng/ml and 1073.87 ng/ml for FTS and aqueous dispersion of CsA (control) respectively. It was found that both niosomal formulation FTS & FSB presented significantly high (p<0.05) Cmax, AUC0-t, MRT 0-inf and half-life (t1/2) as associated to plain drug dispersion. However niosomal formulation FSB exhibited better in-vivo performance as compared to FTS. It was established that CsA can be successfully entrapped in niosomes. So niosomes are promising vehicle for CsA oral delivery.