Biomedical subjects

Fernando Alfieri

Publications and source records attributed to Fernando Alfieri.

4 recordsLinked to original sources

PubMed2005

Concentration-controlled use of sirolimus associated with reduced exposure of cyclosporine in black recipients of primarily living renal allograft donors: 12-month results.

AIM: This study was designed to identify optimal therapeutic sirolimus (SRL) concentrations in black kidney transplant recipients on reduced cyclosporine (CsA) exposure and prednisone. METHODS: Seventy patients (64 living/six deceased) received CsA (8-10 mg/kg/d), prednisone, and 15 mg loading dose followed by 5-mg fixed doses of SRL till day 7 when they were randomized to maintain SRL trough concentrations (high-performance liquid chromatography) of 8-12 (GI = 34) or 15-20 (GII = 36) ng/mL. RESULTS: Mean CsA concentrations were 109 +/- 53 vs. 89 +/- 41 ng/mL and 75 +/- 54 vs. 60 +/- 35 ng/mL (ns) at 2 and 6 months. Accordingly, mean SRL trough concentrations were 12.4 +/- 6.1 vs. 20.0 +/- 9.5 ng/mL (p < 0.001) and 10.8 +/- 5.8 vs. 18.0 +/- 6.1 ng/mL (p < 0.001). The incidence of biopsy-proven acute rejection [13% (GI: 18% vs. GII: 8%, ns)], graft loss or death was 16% (GI: 21% vs. GII: 11%, ns]. There were no deaths and three graft losses (GI = 1; GII = 2). Creatinine clearance was higher in GI (64.5 +/- 17 vs. 54.4 +/- 14.7 mL/min, p = 0.011). The incidence of post-transplant diabetes mellitus was 13% and no CMV disease was observed. CONCLUSION: In black recipients of primarily living renal allograft donors reduced CsA exposure and SRL concentration-controlled regimens produced low incidences of acute rejection, post-transplant diabetes mellitus and CMV disease, with no significant impairment in graft function.

Adult↗

PubMed2005

Sirolimus quantification by high-performance liquid chromatography with ultraviolet detection.

The need to adapt optimal conditions of sirolimus blood level monitoring in laboratories led us to optimize an high-performance liquid chromatography-ultraviolet method and compare the elution performances using the mobile phase A, 68% MeOH/2% acetonitrile (ACN)/30% H(2)O and mobile phase B, 30% MeOH/42% ACN/28% H(2)O. Samples were assayed with 1-chlorobutane, redissolved in MeOH/water and injected onto a C-18 column at 50 degrees C. The assay achieved sensitivity of 2.5-150 ng/ml (CV = 10.6%) and recovery of 92-103.6%. The intra- and interassay precisions ranged from 3.3% to 13% and from 5.9% to 15% for quality controls of 7.5, 60 and 120 ng/ml. The mobile phase A was unable to elute and recover sirolimus and internal standard in the expected retention time and concentration. Under our working conditions, the assay was precise, accurate and sensible, stressing the importance of establishing for the best working conditions according to the staff and demands of the laboratory.

Chromatography, High Pressure Liquid↗

PubMed2004

An open-label randomized trial of the safety and efficacy of sirolimus vs. azathioprine in living related renal allograft recipients receiving cyclosporine and prednisone combination.

BACKGROUND: The ability of sirolimus (SRL), in combination with reduced exposure of cyclosporine, was investigated to prevent acute rejection and associated side effects. METHODS: Between June 1999 and February 2000, 70 recipients of primary one-haplotype living-related donor renal allografts were randomized to receive SRL (2 mg/d) or azathioprine (AZA) (2 mg/kg/d) combined with cyclosporine and prednisone. The primary end-point was a composite of first occurrence of biopsy-confirmed acute rejection, graft loss, or death during the first 3 months after transplantation. RESULTS: From week 4 to month 12, SRL patients received lower cyclosporine (week 4: 364 mg/d vs. 455 mg/d, p = 0.004; month 12: 195 mg/d vs. 255 mg/d, p = 0.038) doses and showed lower cyclosporine concentrations (week 4: 247 ng/mL vs. 309 ng/mL, p = 0.04; month 12: 143 ng/mL vs. 188 ng/mL, p = 0.045). Compared with AZA, SRL patients showed reduced 3-month primary end point (0% vs. 17.1%, p = 0.025), and reduced incidence of biopsy-confirmed acute rejection at 3 months (0% vs. 14.3%, p = 0.01) but not at 12 months (11.4% vs. 14.3%, NS). Mean creatinine at 12 months were not different (1.8 +/- 0.6 vs. 1.6 +/- 0.6, p = 0.23). Hyperlipidemia was the only adverse event more frequent among SRL patients (49% vs. 17%, p = 0.01). There were no differences in infections and no malignancies in both groups. CONCLUSIONS: The combination of 2 mg fixed doses of SRL, reduced cyclosporine exposure and prednisone was associated with a low incidence of acute rejection and did not result in significantly impaired graft function compared with patients receiving AZA, standard doses of cyclosporine and prednisone.

Adult↗

PubMed2003

Determination of sirolimus blood concentration using high-performance liquid chromatography with ultraviolet detection.

BACKGROUND: Different HPLC methods have been developed and used to determined sirolimus blood concentrations. These methods show different performance characteristics, mostly related to peak interference, recovery, assay sensitivity, and turnaround times. OBJECTIVE: We adapted, improved, and validated an HPLC method with UV detection for measurement of sirolimus in whole blood clinical samples. METHODS: The standards, quality controls, or patient samples (0.25 or 0.5 mL) and internal standard (desmethoxysirolimus) were extracted with 1-chlorobutane. After evaporation, the extract was reconstituted in a 70% acetonitrile/water mixture and analyzed onto a reverse-phase C18 column at 50 degrees C under a flow rate of 1.0 mL/min in the HPLC system. Ultraviolet detection was performed at 278 nm, with sensitivity setting of 0.010 AUFS. Identification of peaks of interest was by retention time; quantification of sirolimus was based on a peak area ratio. RESULTS: Analytic recovery ranging from 96 to 120% (CV = 3.7 to 16.8%; bias = -4.2 to 16.7%) was observed throughout the assay's linear range (2.5-150.0 ng/mL). The lower limit of quantification for both sample volumes (0.25 or 0.5 mL) was 2.5 ng/mL (CV = 12 and 15%, bias = -1.2 and 4%, respectively). The intra- and interassay imprecision ranged from 6.2 to 14.4% and from 9.1 to 18.6%, with bias ranging from 1.3 to 12.9% and -1.8% to 7.1, for quality control levels of 3, 10, and 20 ng/mL. Whole blood and extracted samples are stable at room temperature and at 4 and -20 degrees C for 1 week and 3 days, respectively. Chromatograms showed good separation free of interfering peaks. A set of 45 samples can be extracted in 2 h, allowing results within 24 h. CONCLUSION: This HPLC-UV method shows good and reproducible performance, satisfying all requirements of an assay designated to be applied in therapeutic drug monitoring strategies after organ transplantation.

Chromatography, High Pressure Liquid↗