Table 1.

Retrospective and real-world evidence on CDK 4/6 inhibitors in elderly patients.

Trial	No. of Patients	Median Age	CDK 4/6 Inhibitors	Results
American Flatiron Study [73,74]	1400	66 (20% >75 years)	Palbociclib (±Letrozole)	PFS and OS >75 y vs. <75 y
HeLLENIC Cooperative Oncology Group (HeCOG) [75]	365	61 (12% >75 years)	Palbociclib/ribociclib (±ET)	PFS (>75) 10.9 months as 1st line vs. 7.5 months as 2nd line Safety: similar (19% G3-4 adverse events)
CompLEEment–1 [76]	3246	58 (24% >65–75 years; 9.5% >75 years)	Ribociclib/letrozole	Safety and efficacy consistent with that seen in phase III trials
Kish et al. [77]	763	64 (50% <65 years; 20% >75 years)	Palbociclib/ET	Safety and efficacy consistent with Paloma 1 and 2 trials
PALOMAGE [71]	407	79 (15% older than 85 years)	Palbociclib (±ET)	Incidence of grade 3–4 AEs: 40% <80 years; 31% >80 years Dose reduction occurred in 23% of the patients; 30% of the patients older than 80 years