Lower-Dose Regimens of Exemestane Effective in Postmenopausal Patients With Stage 0 to II ER-Positive Breast Cancer

The study results are:

• Researchers randomized 180 women into 1 of the three arms. The study centre was two hospitals in Italy and 3 in US.
• The median age in the once-daily, 3-times-weekly, and once-weekly arms was 66, 63 and 65 years respectively.
• In the intention-to-treat population, including 171 women, the least square mean percentage change of serum estradiol was −89% (once daily, 55 women), −85% (three times weekly, 56 women) and −60% (once weekly, 60 women) respectively.
• The difference in estradiol percentage change was -3.6 % between the once-daily and 3-times-weekly arms, whereas, in compliant participants with 153 women, it was 2.0%.
• Considering secondary endpoints, Ki-67 and progesterone receptors were reduced in all arms.
• The 3-times-weekly arm had a better profile of Sex hormone–binding globulin and high-density lipoprotein cholesterol
• There were similar adverse events in all arms.

Concluding further, they said that giving 25 mg of exemestane thrice weekly in compliant patients was noninferior based on the findings of our study compared to the once-daily dosage in reducing serum estradiol.

The study results should be further investigated in prevention studies and in those women who are intolerant to daily dosing in the adjuvant setting.

Further reading:

Serrano D, Gandini S, Thomas P, et al. Efficacy of Alternative Dose Regimens of Exemestane in Postmenopausal Women With Stage 0 to II Estrogen Receptor–Positive Breast Cancer: A Randomized Clinical Trial. JAMA Oncol. Published online March 23, 2023. doi:10.1001/jamaoncol.2023.0089