Effect of palbociclib plus letrozole on patient-reported health-related quality of life: extended follow-up of the PALOMA-2 trial

Abstract

Background

Metastatic breast cancer (mBC) remains incurable, highlighting the importance of patient-reported outcomes (PROs) in treatment decision making. In the randomized phase III PALOMA-2 trial, health-related quality of life (HRQoL) was maintained in patients receiving first-line palbociclib plus letrozole compared with placebo plus letrozole after a median follow-up of 22.3 months. However, little is known about HRQoL for patients taking palbociclib for an extended period of time. Here, we report the PRO results from the PALOMA-2 trial after a median follow-up time of 90 months.

Patients and methods

Women with estrogen receptor-positive/human epidermal growth factor receptor 2-negative (ER+/HER2−) mBC were randomly assigned 2 : 1 to receive palbociclib plus letrozole (n = 444) or placebo plus letrozole (n = 222). HRQoL was assessed with the Functional Assessment of Cancer Therapy-Breast (FACT-B) and EuroQoL five-dimensions three-level (EQ-5D-3L) questionnaires, administered on site on day 1 of cycles 1, 2, and 3 and then every other cycle from cycle 5 until study end. Treatment arm comparisons were made for change from baseline in QoL and time to deterioration in FACT-B (definitive definition, TTDD).

Results

After a median follow-up of 90 months, no significant differences between treatments were observed for overall change from baseline in FACT-B total, FACT-B subscales, and EQ-5D-3L scores. While TTDD did not differ between treatment arms, TTDD was shorter for patients with disease progression versus those without disease progression (hazard ratio 0.644, P < 0.001). Individual items assessing side-effects and hair loss favored the palbociclib plus letrozole arm versus the letrozole arm; no treatment difference was observed for items assessing pain.

Conclusions

This extended follow-up analysis of PROs in PALOMA-2 shows continued QoL maintenance for patients with ER+/HER2− mBC receiving long-term palbociclib plus letrozole treatment.