Abstract OT1-08-04: A first-in-human phase Ia dose escalation study of GDC-0077, a p110a-selective and mutant-degrading PI3K inhibitor, in patients with PIK3CA-mutant solid tumors

Abstract Background: Activating mutations in PIK3CA, encoding the p110α subunit of phosphatidylinositol 3-kinase (PI3K), are highly prevalent in breast cancer and solid tumor malignancies. GDC-0077 is a potent p110α-selective inhibitor with a novel mechanism of action that degrades mutant p110α and anti-tumor activity in PIK3CA-mutant breast cancer xenograft models as a single agent and in combination with anti-estrogens with or without a CDK4/6 inhibitor. An open-label, Phase I dose-escalation study of GDC-0077 monotherapy and GDC-0077 combined with endocrine therapies and palbociclib is underway in patients (pts) with locally advanced or metastatic PIK3CA-mutant solid tumors. Data from th…

MA15.02 Long-Term Safety and Clinical Activity Results from a Phase Ib Study of Erlotinib Plus Atezolizumab in Advanced NSCLC

Abstract PD1-02: A phase I/Ib study evaluating GDC-0077 + palbociclib (palbo) + fulvestrant in patients (pts) with PIK3CA-mutant (mut), hormone receptor-positive/HER2-negative metastatic breast cancer (HR+/HER2- mBC)

Abstract Background GDC-0077 is a PI3Kα-selective inhibitor and mutant PI3Kα degrader that demonstrates antitumor activity in PIK3CAmut BC xenograft models. A phase I/Ib study of GDC-0077 alone and combined with endocrine therapy ± the CDK4/6 inhibitor (i) palbo is ongoing (NCT03006172). Data from GDC-0077 + palbo + fulvestrant in pts with PIK3CAmut, HR+/HER2- mBC are presented herein. Methods Safety (NCI-CTCAE v4), pharmacokinetics (PK), and preliminary antitumor activity (clinical benefit rate [CBR]: RECIST v1.1 stable disease for ≥ 24 weeks, partial response [PR], or complete response) of 9 mg oral once daily GDC-0077 + 125 mg palbo 21/28 days + 500 mg intramuscular fulvestrant on day 1 …

A phase I/Ib study evaluating GDC-0077 (inavolisib) + palbociclib (palbo) + fulvestrant in patients (pts) with PIK3CA-mutant (mut), hormone receptor-positive/HER2-negative metastatic breast cancer (HR+/HER2- mBC)

Abstract PS5-12: Preliminary correlative analysis of clinical outcomes with PIK3CA mutation (mut) status from a phase I/Ib study of GDC-0077 in patients (pts) with hormone receptor-positive/HER2-negative metastatic breast cancer (HR+/HER2- mBC)

Abstract Background Mutations in p110α, encoded by PIK3CA, are present in ~40% of HR+/HER2- BCs. GDC-0077, a PI3Kα-selective inhibitor and mutant PI3Kα degrader, elicits antitumor activity in PIK3CAmut preclinical models as a single agent and when combined with endocrine therapy (ET). New evidence suggests BCs harboring multiple PIK3CAmut exhibit increased signaling through the PI3K/AKT pathway and are more sensitive to PI3Kα inhibitors compared with BCs with a single PIK3CAmut. We report a preliminary analysis of PIK3CAmut status with clinical outcomes from an ongoing study of GDC-0077 alone or with ET (letrozole/fulvestrant) ± palbociclib (palbo) in pts with PIK3CAmut HR+/HER2- mBC (NCT03…

Abstract P1-19-46: A phase Ib dose escalation study evaluating the mutant selective PI3K-alpha inhibitor GDC-0077 (G) in combination with letrozole (L) with and without palbociclib (P) in patients with PIK3CA-mutant HR+/HER2- breast cancer

Abstract Background: Dysregulation of the PI3K/AKT/mTOR signaling pathway occurs in solid tumor malignancies. GDC-0077 (G) is a potent p110α-selective, p110α-mutant degrading inhibitor with anti-tumor activity in PIK3CA-mutant breast cancer xenograft models as a single agent and in combination with endocrine therapies (ET) with or without a CDK4/6 inhibitor (i). An open-label, Phase I dose escalation study of Galone and in combination with ET and P is underway in patients (pts) with locally advanced or metastatic PIK3CA-mutant solid tumors. Data from the combinations of G and L with and without P in pts with PIK3CA-mutant HR+/HER2- breast cancer are presented herein. Methods: This study (NC…

Abstract PS11-11: Targeted safety events from a phase I/Ib study evaluating GDC-0077 alone and in combination with endocrine therapy (ET) ± palbociclib (palbo) in patients (pts) with PIK3CA-mutant (mut), hormone receptor-positive/HER2-negative metastatic breast cancer (HR+/HER2- mBC)

Abstract Background Activating mutations in PIK3CA, encoding the p110α subunit of phosphatidylinositol 3-kinase (PI3K) occur in ~40% of HR+/HER2- BCs. GDC-0077, a PI3Kα-selective inhibitor and mutant PI3Kα degrader, is being developed as an anticancer agent. A phase I/Ib study of GDC-0077 alone and combined with other therapies is ongoing in pts with locally advanced or metastatic PIK3CAmut, HR+/HER2- mBC (NCT03006172). Targeted safety events are presented here. Methods Safety was assessed via NCI-CTCAE v4 for GDC-0077 administered alone (Arm A), with letrozole and palbo (Arm B), with letrozole (Arm C), with fulvestrant (Arm D), or with fulvestrant and palbo (Arm E, plus metformin in Arm F …

P3.02c-046 Safety, Clinical Activity and Biomarker Results from a Phase Ib Study of Erlotinib plus Atezolizumab in Advanced NSCLC

336P PI3K pathway biomarkers and clinical response in a phase I/Ib study of GDC-0077 in hormone receptor-positive/HER2-negative breast cancer (HR+/HER2– BC)

Abstract CT109: A phase I/Ib study evaluating GDC-0077 plus fulvestrant in patients with PIK3CA-mutant, hormone receptor-positive/HER2-negative breast cancer

Abstract Background: PIK3CA encodes the PI3K p110α subunit, and dysregulating mutations are widely seen in breast cancer (BC) and other solid tumors. GDC-0077 (G) is a potent p110α-selective inhibitor that degrades mutant p110α and demonstrates antitumor activity in PIK3CA-mutant BC xenograft models, either as a single agent, or combined with anti-estrogen therapy. From an ongoing, open-label, phase I/Ib dose-escalation study of G alone and combined with endocrine + targeted therapies (NCT03006172), we present data of G + fulvestrant (F) in postmenopausal patients (pts) with PIK3CA-mutant, hormone receptor-positive/HER2-negative BC, including a food-effect assessment on the pharmacokinetics…