KEY TAKEAWAYS
- PALOMA-2 and PALOMA-3 Phase 3 studies demonstrate Palbociclib with endocrine therapy extends the time to chemotherapy in HR+/HER2- advanced breast cancer patients.
- Postmenopausal patients previously untreated for ABC and premenopausal or postmenopausal patients whose disease had progressed after prior ET, respectively.
- Chemotherapy was received by fewer patients in the PAL plus ET arm than in the PBO plus ET arm in both trials.
- The analyses also revealed that TTC was prolonged with PAL plus ET versus PBO plus ET across the same patient subgroups in both trials.
- PAL plus ET is an effective treatment option for patients with HR+/HER2- ABC, resulting in longer PFS and a delayed need for subsequent chemotherapy.
Patients with hormone receptor-positive/human epidermal growth receptor 2 negative (HR+/HER2-) advanced breast cancer have been shown to have a longer time to first subsequent chemotherapy (TTC) with palbociclib (PAL) plus endocrine therapy (ET) compared to placebo (PBO) plus ET in previous analyses from the PALOMA-2 and PALOMA-3 studies (ABC). In this study, we analyzed TTC in analytical patient groups.
They used information from 2 randomized, phase 3 studies of women with HR+/HER2- ABC to conduct this post hoc analysis of TTC by subgroup. Postmenopausal women without a history of ABC treatment were randomly assigned to either placebo plus letrozole (PBO + LET; n = 222) or PAL (125 mg/day, 3/1-week regimen) in the PALOMA-2 trial. Patients who had disease progression after preceding ET were randomly assigned to receive either PAL (125 mg/day, 3/1-week regimen; n = 347) or PBO (n = 174) plus fulvestrant (FUL; 500 mg; n = 174).
When palbociclib with ET or placebo plus ET failed to prevent progression, 35.5% and 56.2% of patients in PALOMA-2 and PALOMA-3, respectively, received first-line chemotherapy. The median progression-free survival (PFS) for both PAL and ET groups was higher than that for PBO and ET groups across all categories. For the same patient subgroups in both studies, TTC was greater with PAL with ET than with PBO plus ET. In both the PALOMA-2 and PALOMA-3 investigations, PAL plus ET was superior to PBO plus ET in median PFS and TTC.
Source: https://pubmed.ncbi.nlm.nih.gov/36463643/
Clinical trial: https://clinicaltrials.gov/ct2/show/NCT01942135/
Rugo, H.S., Im, S.-A., Joy, A.A., Shparyk, Y., Walshe, J.M., Sleckman, B., Loi, S., Theall, K.P., Kim, S., Huang, X., Bananis, E., Mahtani, R., Finn, R.S. and Diéras, V. (2022). Effect of palbociclib plus endocrine therapy on time to chemotherapy across subgroups of patients with hormone receptor‒positive/human epidermal growth factor receptor 2‒negative advanced breast cancer: Post hoc analyses from PALOMA-2 and PALOMA-3. The Breast, 66, pp.324–331. doi:https://doi.org/10.1016/j.breast.2022.11.005.
