Safety of Combination in Older Women Assessed
Many women with advanced breast cancer are elderly—in fact, >40% of patients with breast cancer are 65 years of age or older;13 therefore, the tolerability profile of everolimus plus exemestane in this population is of interest, stated Kathleen I. Pritchard, MD, of Sunnybrook Odette Cancer Centre, University of Toronto, Toronto, ON, Canada, and colleagues at ASCO 2012.5
Dr. Pritchard reported on safety data from BOLERO-2 at a median follow-up of 18.0 months with a focus on elderly patients, who are especially at risk for noncompliance because of increased chronic illnesses and medications, with the most common risk factor for AEs being the number of drugs taken.14
In general, the safety profiles were found to be similar between older (≥ 65 and ≥ 70 years old) and younger (<65 and <70 years old) patients, with AEs of special interest observed at similar frequencies: pneumonitis (~15% in older vs 17% in younger patients); hyperglycemia (~13% in older vs 15% in younger patients); and hypercholesterolemia (~7% in older vs 12% in younger patients).
In patients ≥65 years of age and ≥70 years of age, the most common AEs were stomatitis (~50%), fatigue (~37%), decreased appetite (~35%) and diarrhea (~35%). In the everolimus plus exemestane arm, mean weight loss from baseline was 5.2 kg both in patients ≥65 years old and in patients <65 years old. In the placebo plus exemestane arm, weight loss was less but similar between age groups, 1.8 kg vs 1.7 kg, respectively.
At the 18-month median follow-up, compared with placebo plus exemestane, everolimus plus exemestane reduced the risk of PFS events by 41% in the ≥65-year-old group and by 55% in the ≥70-year-old groupy. The PFS benefit in elderly patients was comparable to that of younger patients, regardless of age cut-off, Dr. Pritchard noted.
In the everolimus plus exemestane arm, best overall response in patients ≥65 years of age and ≥70 years of age was two complete responses in each age group.
Dr. Pritchard concluded that adding everolimus to exemestane improved PFS in women 65 years of age and older with advanced breast cancer compared with placebo plus exemestane, with grade 3 or 4 AEs uncommon and manageable. Overall, AEs were consistent with the known safety profile of each agent.
Results of these four studies presented at ASCO suggest everolimus plus exemestane represent an effective new option for women with advanced breast cancer, especially for the treatment of elderly patients, who may not tolerate toxic treatments.