Comparison of Acute Side Effects Prevalence of Femara and Letrofem in Postmenopausal Women with Breast Cancer

Abstract

Background: Hormonal therapy is one of the most important regimens for treatment and prophylaxis of recurrences of breast cancer. Among drugs, aromateas inhibitors has established and important role in this field. Letrozole is the most common used drugs in this group in our country. Two brand names of letrozole are available in Iranian drug markets; femara and letrofem. The aim of this study was the comparison of acute side effects of these drugs. Methods: In This clinical trials study, 45 post menopausal women with breast cancer were divided in two groups after surgery and chemotherapy. First one contained 30 patient and the second ontained 15 patient treated with letrofem and femara respectively. Side effects were studied in three steps. Findings: Among 19 studied variables, there were significant differences in frequency and intensity of 7 variables between two groups. These variables were pain, arthralgia, nausea, myalgia, lower extremity edema, fatigue and vertigo. Letrofem had more sever side effects from view point of frequency and intensity in comparison with femara. Conclusion: Observed differences may be due to three reasons including different bioavailability, different levels of estrogen following drug administration and lower amount of samples due to high cost of treatments. Then, it is recommended that bioequivalency test and measurement of estrogen level will be done in future studies with more samples. Key words: Acute side effect, femara, letrofem, post menopausal, breast cancer