探討糖尿病藥品Pioglitazone原廠藥與學名藥療效相等性評估

An Evaluation of the Therapeutic Equivalence of Brand-Name and Generic Anti-Diabetic Pioglitazone

目的：為比較原廠藥與學名藥在藥品療效上是否具相同效果， 本研究選用在控制糖尿病常用的Thiazolidinediones類抗糖尿病藥物pioglitazone。研究方法為「比較相同病患使用原廠藥及改用學名藥後，在糖化血色素（HbA1c）值的表現來比較兩者療效上是否有相等性」。方法：此研究為回溯性研究，於台中某區域教學醫院收集資料，研究對象為2010年9月17日換廠當天前後一個月（8月17日～10月17日）之病患。研究對象資料收集期間為2010年3月1日～9月17日有服用原廠藥，並於2010年9月17日～2011年9月1日持續服用學名藥。取換廠前2010年3月1日～2010年9月1日及換廠後2011年3月1日～2011年9月1日期間兩次HbA1c紀錄。統計方法採取雙尾配對T-檢定（paired-t test）方式來比較兩者換廠前後之HbA1c是否有無顯著的差異。結果：納入本研究之病患共158人。排除研究期間不符合條件之病患後共37人。結果發現換廠前後的HbA1c平均值並不具有統計學上的差異（p=0.863）。結論：本研究顯示服用此兩者不同廠牌的pioglitazone藥品，似乎對於糖尿病病患控制HbA1c値上，並無統計學上的差異。因此對病患血糖控制上的差異，原廠藥與學名藥之間的疑慮是無法被證實的。

Purposes: Pioglitazone, an anti-diabetic thiazolidinedione that is commonly used to control diabetes, was studied to determine whether brand-name and generic preparations were therapeutic equivalents by comparing the glycated hemoglobin (HbA1c) levels of the same patients. Methods: In this retrospective study, data were collected from a regional teaching hospital in Taichung from August 17 to October 17, 2010 (one month before and after September 17, 2010, the day of the switch from the brand-name to the generic drug). Study subjects must have taken the brand-name drug from March 1 to September 17, 2010, and continually taken the generic drug from September 17, 2010 and September 1, 2011. Two HbA1c levels were taken from March 1, 2010 ~ September 1, 2010 and March 1, 2011 ~ September 1, 2011 as representative values for before and after the switch. A two-tailed paired t-test was used to determine whether there was a significant difference between HbA1c levels before and after switching from the brand-name to the generic drug. Results: Initially, 158 patients were included in this study; however, after patients who did not meet the study criteria were excluded, 37 remained. There was no statistical difference (p=0.863) between the mean levels of HbA1c before and after the switch from the brandname to the generic drug. Conclusions: The two pioglitazone products did not a show statistical difference in HbA1c levels of diabetic patients. Therefore, concern about a difference in blood sugar control between these drugs is unwarranted.