美國食物及藥物管理局（USFDA）與加拿大衛生部(Health Canada)通知衛生專業人士以下兩則分別關於deferasirox (商品名：Exjade®)及異維A酸(isotretinoin)安全性的最新資訊, 簡述如下：
Deferasirox (Exjade®)
美國諾華公司(Novartis)與USFDA發出的通告指Exjade®有可能引起腎功能損傷(包括腎衰竭)﹑肝功能損傷(包括肝衰竭)以及胃腸道出血等不良反應。上述不良反應於年長患者﹑骨髓異常增生綜合症(myelodysplastic syndrome, MDS)的高危病患﹑潛在的腎臟﹑肝臟損傷患者以及血小板過低的人士中更易發生, 且有可能是致命的。因此, 美國諾華公司(Novartis)和USFDA決定在此藥物的說明書中加入以下的禁忌症資訊：
i) 肌酐清除率小於40 mL/min或血清肌酐大於兩倍與年齡相應的正常值上限。
ii) 骨髓異常增生綜合症病情危急或惡化, 以及晚期惡性腫瘤。
iii)血小板數少於50x109/L。
iv) 已知對deferasirox或Exjade®中任一成份過敏者。
此外, 需對使用Exjade®的病人進行密切監測, 包括以下措施：
i) 於開始治療前檢測血清肌酐和/或肌酐清除率, 然後每月檢測一次；對於具有潛在腎功能損傷或危險因子的病人, 首月每星期檢測一次肌酐和/或肌酐清除率, 然後每月檢測一次。
ii)於開始治療前檢測血清轉氨酶和膽紅素, 首月每兩個星期檢測一次, 然後每月檢測一次。
Isotretinoin
加拿大衛生部向衛生專業人士發出關於isotretinoin安全性的最新資訊, 簡述如下：
i) 上市後通報的個案中, 發現十分罕見的嚴重皮膚反應, 如多形性紅斑(erythema multiforme, EM)、史提芬-強生綜合症(Stevens-Johnson syndrome, SJS)及毒性表皮溶解症(toxic epidermal necrolysis, TEN), 與服用isotretinoin存在關聯性。
ii) 上述不良反應可能很嚴重, 並足以導致住院﹑殘疾或死亡。
iii) 應密切監測病人發生的不良反應, 一旦出現嚴重皮膚反應, 應考慮停藥。
備註：獲准在本澳市場供應的含異維A酸(isotretinoin)藥物包括Acnotin 10 Cap﹑異維A酸膠丸10MG﹑Isotretinoina Ratiopharm﹑Isotrex Cream/Gel﹑Oratane Cap以及Roaccutane Cap。
The United States Food and Drug Administration (USFDA) and Health Canada notified healthcare professionals about the two latest updates respectively on deferasirox (Exjade®) and isotretinoin. Summaries are listed as follows:
Deferasirox (Exjade®)
Novartis Oncology and USFDA notified that the product may cause renal impairment(including failure), hepatic impairment(including failure) and gastrointestinal hemorrhage. These reactions were more frequently observed in patients with advanced age, high risk myelodysplastic syndromes, underlying renal or hepatic impairment or low platelet counts, and they could be fatal. Therefore Novartis and USFDA have decided to add the followings on contraindications:
i) Creatinine clearance<40 mL/min or serum creatinine>2 times the age-appropriate upper limit of normal.
ii) Poor performance status and high-risk myelodysplastic syndromes or advanced malignancies.P
iii) telet counts <50 x 109L.
iv) Known hypersensitivity to deferasirox or to any other component of Exjade®.
In addition, Exjade® therapy requires close patient monitoring, including measurement of:
i) serum creatinine and/or creatinine clearance prior to initiation of therapy and monthly thereafter; in patients with underlying renal impairment or risk factors for renal impairment, monitor creatinine and/or creatinine clearance weekly for the first month, then monthly thereafter.
ii) serum transaminases and bilirubin prior to initiation of therapy, every two weeks during the first month and monthly thereafter.
Isotretinoin
Health Canada informed prescribers of important new safety information regarding the use of isotretinoin:
i) There have been very rare post-marketing reports of severe skin reactions (e.g. erythema multiforme [EM], Stevens-Johnson syndrome [SJS], and toxic epidermal necrolysis [TEN] ) associated with isotretinoin use.
ii) These events may be serious and result in hospitalization, disability or death.
iii) Patients should be monitored closely for severe skin reactions and discontinuation of isotretinoin should be considered if warranted.
Note：The isotretinoin-containing medications authorized for distribution in the Macao market include Acnotin 10 Cap﹑Isotretinoin Capsules 10MG﹑Isotretinoina Ratiopharm﹑Isotrex Cream/Gel﹑Oratane Cap and Roaccutane Cap.
參考資料/References：
https://www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHumanMedicalProducts/ucm200850.htm
https://www.fda.gov/downloads/Safety/MedWatch/SafetyInformation/SafetyAlertsforHumanMedicalProducts/UCM200858.pdf
https://www.hc-sc.gc.ca/dhp-mps/alt_formats/pdf/medeff/advisories-avis/prof/2010/accutane_2_hpc-cps-eng.pdf