Me-too validation study for in vitro skin irritation test with a reconstructed human epidermis model, KeraSkin™ for OECD test guideline 439.

We conducted a me-too validation study to confirm the reproducibility, reliability, and predictive capacity of KeraSkin™ skin irritation test (SIT) as a me-too method of OECD TG 439. With 20 reference chemicals, within-laboratory reproducibility (WLR) of KeraSkin™ SIT in the decision of irritant or non-irritant was 100%, 100%, and 95% while between-laboratory reproducibility (BLR) was 100%, which met the criteria of performance standard (PS, WLR≥90%, BLR≥80%). WLR and BLR were further confirmed with intra-class correlation (ICC, coefficients >0.950). WLR and BLR in raw data (viability) were also shown with a scatter plot and Bland-Altman plot. Comparison with existing VRMs with Bland-Altman plot, ICC and kappa statistics confirmed the compatibility of KeraSkin™ SIT with OECD TG 439. The predictive capacity of KeraSkin™ SIT was estimated with 20 reference chemicals (the sensitivity of 98.9%, the specificity of 70%, and the accuracy of 84.4%) and additional 46 chemicals (for 66 chemicals [20 + 46 chemicals, the sensitivity, specificity and accuracy: 95.2%, 82.2% and 86.4%]). The receiver operating characteristic (ROC) analysis suggested a potential improvement of the predictive capacity, especially sensitivity, when changing cut-off (50% → 60-75%). Collectively, the me-too validation study demonstrated that KeraSkin™ SIT can be a new me-too method for OECD TG 439.

Clinical and cost effectiveness of bevacizumab + FOLFIRI combination versus FOLFIRI alone as first-line treatment of metastatic colorectal cancer in South Korea.

BACKGROUND: Bevacizumab has been extensively investigated in combination with various standard chemotherapies in the treatment of metastatic colorectal cancer (mCRC). However, a comparison to irinotecan + infusional 5-fluorouracil/leucovorin (FOLFIRI) is lacking. OBJECTIVE: To explore clinical effectiveness and cost-effectiveness of adding bevacizumab to a regimen of FOLFIRI for the first-line treatment of mCRC in the Republic of Korea by conducting an indirect treatment comparison. METHODS: A health-economic model was developed to investigate the possible health outcomes (life-years gained [LYG]), direct costs, and incremental cost-effectiveness ratio (ICER) of adding bevacizumab to a FOLFIRI regimen. Data on progression-free and overall survival were derived from randomized clinical trials and were used in the indirect treatment comparison. The annual discount rate for costs and outcomes was 5%. A lifetime horizon of 8 years was used. Sensitivity analyses were carried out on all pivotal model assumptions. RESULTS: Incremental mean overall survival among patients treated with bevacizumab + FOLFIRI varied between 8.6 and 15.7 months compared with patients treated with FOLFIRI alone. The deterministic base-case result was 1.177 LYG. The discounted ICERs ranged from µ31.8 to µ39.5 million/LYG, with the base-case result being µ34.5 million/LYG. Treatment effect had the most impact on the outcomes in this model. CONCLUSIONS: Although there is no formal threshold for ICER per LYG in Korea, funding may be considered for bevacizumab + FOLFIRI, particularly if the severity and end-of-life nature of mCRC is taken into account.

Nephrotoxic potential and toxicokinetics of tetrabromobisphenol A in rat for risk assessment.

Tetrabromobisphenol A (TBBPA), one of the most widely used global brominated flame retardants, is used to improve fire safety of laminates in electrical and electronic equipment. To investigate the nephrotoxic potential of TBBPA and its toxicokinetic profile in rats, single-dose and daily 14-d repeated-dose toxicity studies at 200, 500, or 1000 mg/kg were performed. Several biochemical parameters were analyzed to evaluate nephrotoxicity of TBBPA. High-dose 1000 mg/kg TBBPA significantly elevated renal thiobarbituric acid-reactive substance (TBARS) levels, and superoxide dismutase (SOD) activity was increased at all 3 doses administered. This was associated with no change in the activity of catalase (CAT). Our results suggest that acute 1-d high-dose administration of TBBPA produced transient renal changes at 5 h. Subsequently, TBBPA in serum, urine, and kidney was determined by liquid chromatography-mass spectroscopy (LC/MS). Toxicokinetic studies indicated that TBBPA shows relatively a short half-life (7-9 h) and was eliminated almost completely in feces by 2 d. Based on the results from the 14-d repeated-dose study, TBBPA did not accumulate in the rat, and was eliminated in feces. The present results suggested that TBBPA may not be toxic to kidney, as the chemical is not bioavailable and is not present in renal tissue.