135MO HRQoL with neoadjuvant pembrolizumab + chemotherapy vs placebo + chemotherapy, followed by adjuvant pembrolizumab vs placebo for early-stage TNBC: Results from KEYNOTE-522

Abstract

In the phase III KEYNOTE-522 study (NCT03036488), neoadjuvant (neoadj) pembrolizumab (pembro) + chemotherapy (chemo) vs placebo (pbo) + chemo followed by adjuvant (adj) pembro vs pbo in patients (pts) with early-stage TNBC showed a statistically significant improvement in pCR (ypT0/Tis ypN0) and EFS (dual primary endpoints). We present PRO endpoint results from KEYNOTE-522. Pts with previously untreated, nonmetastatic, centrally confirmed TNBC (stage T1c N1-2 or T2-4 N0-2 per AJCC) were randomized 2:1 to neoadj pembro 200 mg Q3W or pbo, both given with 4 cycles of paclitaxel + carboplatin then 4 cycles of doxorubicin or epirubicin + cyclophosphamide. After surgery, pts received adj pembro or pbo for up to 9 cycles. PROs measured with EORTC QLQ-30 and QLQ-BR23 were prespecified secondary objectives, and with EQ-5D VAS were exploratory objectives. PROs were assessed during the neoadj and adj treatment phases and analyzed for pts who received at least 1 study treatment and completed ≥1 PRO assessment within the neoadj and adj treatment phases. Between-group differences in LS mean change from baseline to the latest time point with ≥60%/80% completion/compliance were assessed using a longitudinal model (no alpha assigned). A threshold of 10 points has been published as a meaningful change. PRO analyses for QLQ-C30 included 1145 pts in the neoadj phase (pembro + chemo; n = 762; pbo + chemo, n = 383) and 847 in the adj phase (n = 539; n = 308). Completion/compliance rates at wk 21 in neoadj phase and wk 24 in adj phase were ≥80% in both pembro and pbo groups. There were no meaningful differences between treatment group in PRO results (Table).Table: 135MOBetween-group difference in LS mean change from baseline to Wk 21 (Neoadj) or Wk 24 (Adj) in PRO endpoints in all pts with TNBCPrespecified ScaleaBetween-Group Difference (Pembro vs Pbo) LS Mean (95% CI)NeoadjbAdjcQLQ-C30- GHS/QoL−1.04 (−3.46, 1.38)−0.41 (−2.60, 1.77)- Emotional functioning−0.69 (−3.13, 1.75)−0.60 (−2.99, 1.79)- Physical functioning−2.85 (−5.11, −0.60)−1.57 (−3.36, 0.21)QLQ-BR23−0.13 (−1.92, 1.65)0.29 (−2.05, 2.63)EQ-5D VAS−1.61 (−3.87, 0.64)−0.59 (−2.40, 1.23)aPRO score range: 0–100.bQLQ-C30 (pembro + chemo, n = 762; pbo + chemo, n = 383); QLQ-BR23 (n = 759; n = 382); EQ-5D VAS (n = 762; n = 384).cQLQ-C30 (n = 539; n = 308); QLQ-BR23 (n = 538; n = 306); EQ-5D VAS (n = 540; n = 310). Open table in a new tab aPRO score range: 0–100. bQLQ-C30 (pembro + chemo, n = 762; pbo + chemo, n = 383); QLQ-BR23 (n = 759; n = 382); EQ-5D VAS (n = 762; n = 384). cQLQ-C30 (n = 539; n = 308); QLQ-BR23 (n = 538; n = 306); EQ-5D VAS (n = 540; n = 310). Neoadj pembro + chemo followed by adj pembro did not have a negative meaningful impact on HRQoL vs pbo control in pts with previously untreated early-stage TNBC, reinforcing the clinical benefit seen with this regimen.