TY - JOUR
T1 - Alpelisib Plus Fulvestrant in PIK3CA -Altered and PIK3CA -Wild-Type Estrogen Receptor-Positive Advanced Breast Cancer
T2 - A Phase 1b Clinical Trial
AU - Juric, Dejan
AU - Janku, Filip
AU - Rodón, Jordi
AU - Burris, Howard A.
AU - Mayer, Ingrid A.
AU - Schuler, Martin
AU - Seggewiss-Bernhardt, Ruth
AU - Gil-Martin, Marta
AU - Middleton, Mark R.
AU - Baselga, José
AU - Bootle, Douglas
AU - Demanse, David
AU - Blumenstein, Lars
AU - Schumacher, Karl
AU - Huang, Alan
AU - Quadt, Cornelia
AU - Rugo, Hope S.
N1 - Funding Information:
Funding/Support: This study was supported by
Publisher Copyright:
© 2019 American Medical Association. All rights reserved.
PY - 2019/2
Y1 - 2019/2
N2 - Importance: The phosphatidylinositol 3-kinase (PI3K) pathway is frequently activated in patients with estrogen receptor-positive (ER+), endocrine therapy-resistant breast cancers. Objective: To assess the maximum tolerated dose (MTD), safety, and activity of alpelisib, an oral, PI3Kα-specific inhibitor, plus fulvestrant in patients with ER+ advanced breast cancer (ABC). Design, Setting, and Participants: An open-label, single-arm, phase 1b study of alpelisib plus fulvestrant was conducted at 10 centers in 5 countries. Participants were 87 postmenopausal women with PIK3CA-altered or PIK3CA-wild-type ER+ ABC, whose cancer progressed during or after antiestrogen therapy. The study began enrolling patients October 5, 2010, and the data cutoff was March 22, 2017. Interventions: Escalating doses of alpelisib were administered once daily, starting at 300 mg, plus fixed-dose fulvestrant, 500 mg, in the dose-escalation phase; alpelisib at the recommended phase 2 dose plus fulvestrant in the dose-expansion phase. Main Outcomes and Measures: The primary end point was determination of the MTD of once-daily alpelisib plus fulvestrant. Secondary end points included safety and preliminary activity. Results: From October 5, 2010, to March 22, 2017, 87 women (median age: 58 years [range, 37-79 years]; median of 5 prior lines of antineoplastic therapy) received escalating once-daily doses of alpelisib (300 mg, n = 9; 350 mg, n = 8; 400 mg, n = 70) plus fixed-dose fulvestrant (500 mg). During dose escalation, dose-limiting toxic effects were reported in 1 patient (alpelisib, 400 mg): diarrhea (grade 2), vomiting, fatigue, and decreased appetite (all grade 3). The MTD of alpelisib when combined with fulvestrant was 400 mg once daily, and the recommended phase 2 dose was 300 mg once daily. Overall, the most frequent grade 3/4 adverse events with alpelisib, 400 mg, once daily (≥10% of patients), regardless of causality, were hyperglycemia (19 [22%]) and maculopapular rash (11 [13%]); 9 patients permanently discontinued therapy owing to adverse events. Median progression-free survival at the MTD was 5.4 months (95% CI, 4.6-9.0 months). Median progression-free survival with alpelisib, 300 to 400 mg, once daily plus fulvestrant was longer in patients with PIK3CA-altered tumors (9.1 months; 95% CI, 6.6-14.6 months) vs wild-type tumors (4.7 months; 95% CI, 1.9-5.6 months). Overall response rate in the PIK3CA-altered group was 29% (95% CI, 17%-43%), with no objective tumor responses in the wild-type group. Conclusions and Relevance: Alpelisib plus fulvestrant has a manageable safety profile in patients with ER+ ABC, and data suggest that this combination may have greater clinical activity in PIK3CA-altered vs wild-type tumors. Trial Registration: ClinicalTrials.gov identifier: NCT01219699.
AB - Importance: The phosphatidylinositol 3-kinase (PI3K) pathway is frequently activated in patients with estrogen receptor-positive (ER+), endocrine therapy-resistant breast cancers. Objective: To assess the maximum tolerated dose (MTD), safety, and activity of alpelisib, an oral, PI3Kα-specific inhibitor, plus fulvestrant in patients with ER+ advanced breast cancer (ABC). Design, Setting, and Participants: An open-label, single-arm, phase 1b study of alpelisib plus fulvestrant was conducted at 10 centers in 5 countries. Participants were 87 postmenopausal women with PIK3CA-altered or PIK3CA-wild-type ER+ ABC, whose cancer progressed during or after antiestrogen therapy. The study began enrolling patients October 5, 2010, and the data cutoff was March 22, 2017. Interventions: Escalating doses of alpelisib were administered once daily, starting at 300 mg, plus fixed-dose fulvestrant, 500 mg, in the dose-escalation phase; alpelisib at the recommended phase 2 dose plus fulvestrant in the dose-expansion phase. Main Outcomes and Measures: The primary end point was determination of the MTD of once-daily alpelisib plus fulvestrant. Secondary end points included safety and preliminary activity. Results: From October 5, 2010, to March 22, 2017, 87 women (median age: 58 years [range, 37-79 years]; median of 5 prior lines of antineoplastic therapy) received escalating once-daily doses of alpelisib (300 mg, n = 9; 350 mg, n = 8; 400 mg, n = 70) plus fixed-dose fulvestrant (500 mg). During dose escalation, dose-limiting toxic effects were reported in 1 patient (alpelisib, 400 mg): diarrhea (grade 2), vomiting, fatigue, and decreased appetite (all grade 3). The MTD of alpelisib when combined with fulvestrant was 400 mg once daily, and the recommended phase 2 dose was 300 mg once daily. Overall, the most frequent grade 3/4 adverse events with alpelisib, 400 mg, once daily (≥10% of patients), regardless of causality, were hyperglycemia (19 [22%]) and maculopapular rash (11 [13%]); 9 patients permanently discontinued therapy owing to adverse events. Median progression-free survival at the MTD was 5.4 months (95% CI, 4.6-9.0 months). Median progression-free survival with alpelisib, 300 to 400 mg, once daily plus fulvestrant was longer in patients with PIK3CA-altered tumors (9.1 months; 95% CI, 6.6-14.6 months) vs wild-type tumors (4.7 months; 95% CI, 1.9-5.6 months). Overall response rate in the PIK3CA-altered group was 29% (95% CI, 17%-43%), with no objective tumor responses in the wild-type group. Conclusions and Relevance: Alpelisib plus fulvestrant has a manageable safety profile in patients with ER+ ABC, and data suggest that this combination may have greater clinical activity in PIK3CA-altered vs wild-type tumors. Trial Registration: ClinicalTrials.gov identifier: NCT01219699.
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U2 - 10.1001/jamaoncol.2018.4475
DO - 10.1001/jamaoncol.2018.4475
M3 - Article
C2 - 30543347
AN - SCOPUS:85058642503
SN - 2374-2437
VL - 5
JO - JAMA Oncology
JF - JAMA Oncology
IS - 2
ER -