Comparative in vitro Cytotoxicity of the Generic and Reference Products of Gemcitabine on Various Cancer Cell Lines
Abstract
Background and objectives : Gemcitabine is a chemotherapeutic agent which can be used for the treatment of several cancers. Recent clinical studies demonstrated that gemcitabine alone or in combination with cisplatin are effective for treatment of cholangiocarcinoma (CCA). To date, several generic products of gemcitabine are now available in Thailand and the price of these products are lower than the reference product. This study aimed to determine the cytotoxic activity of gemcitabine on several human cancer cell lines as well as to compare the in vitro cytotoxicity of the generic gemcitabine product (Gemita®, Fresenius Kabi Oncology Ltd.; formerly Dabur Pharma Ltd.) with its reference product (Gemzar®, Eli Lilly) in the similar experimental conditions.
Methods : Cancer cell lines used in the present study were CCA cell lines (KKU-M055, KKU-M213, KKU-M214), cervical cancer cell line (HeLa), colon cancer cell line (SW620) and the lung cancer cell line (A549). The growth inhibitory effect of gemcitabine on these cancer cell lines was measured by the sulforhodamine B assay. The concentration of drug required to inhibit cell proliferation by 50% (IC50) was determined by plotting the percentage of cell viability versus the drug concentrations. Comparisons of IC50 values of the generic product with the reference product were analyzed using independent t-test.
Results : The sensitivities to gemcitabine were varied in the 3 different human CCA cell lines, KKU-M055, KKU-M213 and KKU-M214, with the IC50 values ranging from 52-1,832 nM and KKU-M055 was the most sensitive cell line. The cytotoxic effects of these products on cervical cancer (HeLa), colon cancer (SW620) and lung cancer (A549) cell lines were very similar (IC50 13.44 to 22.97 nM). No statistically significant differences were found between the IC50 values for the test product (Gemita®) and the reference product (Gemzar®) on these cancer cell lines (p>0.05).
Conclusions : Several human cancer cell lines including CCA, cervical cancer, colon cancer and lung cancer cell lines were sensitive to gemcitabine. The IC50 values of the generic product, Gemita®, of all the cancer cell lines tested in the present study, were not significantly different from its reference product, Gemzar®. This suggests that the in vitro cytotoxicity of these two products on cancer cell lines are not statistical significant different.
Key words: Gemcitabine, Gemita®, Gemzar®, Human cancer cell lines