Head-to-head evidence
Palbociclib vs Ribociclib
Same mechanism, same race: design-graded trial evidence for both assets, with the grading rationale shown. Grades describe the quality of the evidence, never the merits of either security.
HR+/HER2- Metastatic Breast Cancer
Shared mechanism: CDK4 and CDK6 · full HR+/HER2- Metastatic Breast Cancer pipeline
Palbociclib · Ibrance
Marketed by Pfizer
NCT01740427 · Phase 3 · completed
This was a randomized, quadruple-blind, placebo-controlled phase 3 trial with 666 participants. Its primary clinical endpoint, investigator-assessed progression-free survival using RECIST criteria, was significantly improved with palbociclib plus letrozole (hazard ratio 0.576; p<0.000001), supporting a strong evidence grade.
Next expected readout: November 2026 · NCT02605486 (registry estimate)
Ribociclib
Marketed by Novartis
NCT02422615 · Phase 3 · completed
The study randomly assigned 726 participants to ribociclib plus fulvestrant or placebo plus fulvestrant and was quadruple-blinded for the primary comparison. Its radiographically assessed progression-free survival endpoint was significantly better with ribociclib; participants were later unblinded and offered crossover after a protocol amendment.
Next expected readout: November 2026 · NCT02608216 (registry estimate)
The full competitive landscape for each asset (every same-race competitor with aligned evidence, sortable) is on the asset pages: Palbociclib's landscape · Ribociclib's landscape