- Neoadjuvant ipatasertib (IPAT)+paclitaxel in patients with early triple-negative breast cancer (eTNBC) did not increase the pathologic complete response (pCR) rate, but did attain higher rates of response by breast MRI, especially in biomarker-selected patients, according to phase 2 FAIRLANE trial.
Why this matters
- IPAT is among the first new therapies for eTNBC.
- Results reported here warrant progression to phase 3.
- Double-blind randomized controlled trial (n=151 in the intent-to-treat [ITT] group) of weekly paclitaxel 80 mg/m2 with IPAT 400 mg or placebo (days 1-21 every 28 days) for 12 weeks before surgery.
- Coprimary outcomes were pCR in the ITT group and PTEN-low group by immunohistochemistry.
- Funding: F. Hoffmann-LaRoche; SOLTI group.
- No increase in pCR (IPAT group vs placebo) in 3 groups: ITT, PTEN-low subgroup, or PIK3CA/AKT1/PTEN-altered subgroup by next-generation sequencing.
- IPAT groups (vs placebo) showed higher rates of overall (ORR) and complete response rates (CRR) by MRI in all 3 groups: ITT, PTEN-low subgroup, and PIK3CA/AKT1/PTEN-altered subgroup.
- The greatest benefit was seen in CRR of the PIK3CA/AKT1/PTEN-altered subgroup (IPAT group vs placebo, respectively: 39% [95% CI, 22%-59%] vs 9% [95% CI, 2%-22%]).
- The IPAT group had more grade ≥3 adverse events, especially diarrhea.
- Short length of trial may explain low pCR rates.