Incidence, management, and resolution of stomatitis and noninfectious pneumonitis in BOLERO-2.

Abstract

159 Background: Although the mTOR inhibitor everolimus (EVE) was generally well tolerated in combination with exemestane (EXE) in patients (pts) with HR+/HER2– advanced breast cancer, stomatitis and noninfectious pneumonitis (NIP) are the most clinically relevant and potentially dose-limiting toxicities. The incidence, grade, and clinical course of stomatitis and NIP among pts participating in the BOLERO-2 study are described. Methods: Pts were randomized 2:1 to receive EVE + EXE or placebo (PBO) + EXE. Incidence and severity of stomatitis and NIP, consequent dose interruptions/adjustments, study drug discontinuations, and time to resolution were recorded. Results: Stomatitis (any grade) occurred more frequently with EVE + EXE than with PBO + EXE (59% vs 12%, respectively). Grade 3 stomatitis occurred in 8% vs 1% of EVE + EXE vs PBO + EXE pts, respectively; no grade 4 events were reported. Onset of grade ≥ 2 stomatitis after treatment initiation was earlier for EVE + EXE arm vs PBO + EXE: median time was 15 d vs 24 d, respectively. For the EVE + EXE arm, 97% of pts with grade 3 stomatitis (n = 38) improved to ≤1 after a median of 13 d. Complete resolution was observed in 82% of pts after a median of 38 d. For the PBO + EXE arm, all pts with grade 3 stomatitis (n = 2) improved to ≤1 after a median of 18 d. Complete resolution was observed after a median of 29 d. 24% of pts on EVE + EXE required dose interruptions/adjustments vs 1% of pts on PBO + EXE, and 3% of pts (n = 13) discontinued EVE + EXE vs <1% of pts (n = 1) discontinuing PBO + EXE, all related to stomatitis. Overall, 16% in the EVE + EXE vs 0% in the PBO + EXE groups had a diagnosis consistent with NIP. For EVE + EXE, grade 1, 2, and 3 NIP occurred in 7%, 6%, and 3% of pts, respectively; no grade 4 events were reported. Complete resolution of NIP to grade ≤1 was recorded for all but 4 pts for whom NIP was still observed at last follow-up before study discontinuation. Overall, in the EVE + EXE arm, NIP was reason for dose interruption and treatment discontinuation in 7.5% and 5.6% of pts, respectively. Conclusions: In the BOLERO-2 study, stomatitis and NIP were of mild to moderate intensity and were generally reversible. Most incidents were successfully managed with palliative interventions and temporary dose modifications. Clinical trial information: NCT00863655.