Abstract

Objectives

A new LT4 formulation (Euthyrox [LT4 NF]) was developed to meet new regulatory standards, and has replaced the older formulation (LT4 OF) in a number of countries. We evaluated the possibility of tolerability/safety concerns associated with the switch by analysing spontaneous adverse event (AE) reports before and after switching.

Methods

We examined spontaneous reports of adverse events (AE) from 18 countries generated from individual case safety reports (ICSRs) submitted to the pharmaceutical sponsor’s global safety database, over one year before/one year after the switch.

Results

There was no clear pattern relating to the numbers of ICSRs received before and after the switch across the countries. ICSRs contained a total of 634 AE relating to thyroid imbalance (82 serious) with LT4 OF over the period of one year; 343 such AE (60 serious) were reported for LT4 NF. The most common thyroid imbalance AE for LT4 OF concerned hypothyroidism or hyperthyroidism, unspecified thyroid function test abnormalities, and dosing issues. More AE of any aetiology were reported for LT4 NF (5098) vs. LT4 OF (4439), although the number of serious AE was lower for LT4 NF vs. LT4 OF (457 and 580, respectively). Fatigue, dizziness, headache, palpitations, and nausea were among the most common AE reported for each formulation. The nature of AE was comparable between formulations.

Conclusions

No new safety concerns arose concerning the updated LT4 formulation in the 18 countries. Careful counselling of patients and adherence to routine thyroid care is important.

中文翻译：

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为满足新的和更严格的监管要求而设计的左甲状腺素新配方的真实世界临床经验

摘要

目标

开发了一种新的 LT4 配方（Euthyrox [LT4 NF]）以满足新的监管标准，并在许多国家取代了旧的配方（LT4 OF）。我们通过分析转换前后的自发性不良事件 (AE) 报告来评估与转换相关的耐受性/安全性问题的可能性。

方法

我们检查了来自 18 个国家的自发的不良事件 (AE) 报告，这些报告是在转换前一年/一年后提交给药物申办者的全球安全性数据库的个案安全报告 (ICSR) 生成的。

结果

各国在转换前后收到的 ICSR 数量没有明确的模式。ICSR 包含 634 例与甲状腺失衡相关的 AE（82 例严重），在一年内伴有 LT4 OF；LT4 NF 报告了 343 例此类 AE（60 例严重）。LT4 OF 最常见的甲状腺失衡 AE 涉及甲状腺功能减退或甲状腺功能亢进、未明确的甲状腺功能测试异常和剂量问题。LT4 NF (5098) 与 LT4 OF (4439) 报告了更多任何病因的 AE，尽管 LT4 NF 与 LT4 OF 的严重 AE 数量较低（分别为 457 和 580）。疲劳、头晕、头痛、心悸和恶心是每种制剂报告的最常见的 AE 之一。AE的性质在制剂之间是可比的。

结论

在 18 个国家/地区，更新的 LT4 配方没有出现新的安全问题。仔细咨询患者并坚持常规甲状腺护理很重要。