- Results of the SANDPIPER phase 3 randomized controlled trial (RCT) show that taselisib for PIK3CA-mutant hormone receptor (HR)-positive HER2-negative advanced breast cancer is only modestly effective and has numerous safety problems.
Why this matters
- Authors: taselisib has "no clinical utility."
- Placebo-controlled RCT comparing taselisib (4 mg) or placebo plus fulvestrant (500 mg) in postmenopausal women with disease recurrence/progression during/after an aromatase inhibitor.
- Primary outcome: investigator-assessed PFS in patients with PIK3CA-mutant tumors.
- Funding: F. Hoffmann-La Roche Ltd.
- PFS was longer with taselisib vs placebo:
- 7.4 (95% CI, 7.26-9.07) vs 5.4 (95% CI, 3.68-7.29) months.
- Stratified HR: 0.70 (P=.0037).
- Versus the placebo group, the taselisib group had higher rates of serious adverse events (32% vs 8.9%), discontinuations (16.8% vs 2.3%), and dose reductions (36.5% vs 2.3%).
- Study period too short to evaluate OS.