0000000000017525
AUTHOR
Yibing Yan
PI3K/AKT Activation and Response in Phase IB: AKT Inhibitor GDC-0068 with Docetaxel (D) Or MFOLFOX6 (F) in Refractory Solid Tumors
R. Meng1, L. R. Molife2, L. de Mattos-Arruda3, A. Hollebecque4, S. J. Isakoff5, D. Roda6, Y. Yan1, A. Cervantes6, J. C. Soria4, J. Mateo2, G. Argiles3, J. C. Bendell7 Genentech, South San Francisco, CA, USA, Institute of Cancer Research/ Royal Marsden Hospital, Sutton, United Kingdom, Vall d’Hebron University Hospital, Barcelona, Spain, Institut Gustave Roussy, Villejuif, France, Massachusetts General Hospital, Boston, MA, USA, Institute of Health Research INCLIVA, University of Valenica, Valencia, Spain, Sarah Cannon Research Institute, Nashville, TN, USA
Abstract B154: A first-in-human trial of GDC-0068: A novel, oral, ATP-competitive Akt inhibitor, demonstrates robust suppression of the Akt pathway in surrogate and tumor tissues.
Abstract GDC-0068 is a highly selective ATP-competitive small molecule that inhibits all three isoforms of Akt with IC50 values of 5 to 30 nM. GDC-0068 selectively inhibits cancer cells with activated Akt signaling (e.g. via PTEN loss or PIK3CA mutations). Patients with advanced solid tumors were treated with GDC-0068 using a 3+3 escalation design. GDC-0068 was dosed PO QD on a 21-day on, 7-day off schedule; endpoints included safety, pharmacokinetics (PK) and determination of pathway knockdown. Pharmacodynamics (PD) endpoints in surrogate tissue [platelet rich plasma (PRP)] were evaluated in all patients. In addition, at least two patients per cohort had pre- and on-treatment (day 15) tumo…
Evaluation and clinical analyses of downstream targets of the Akt inhibitor GDC-0068.
Abstract Purpose: The oncogenic PI3K/Akt/mTOR pathway is an attractive therapeutic target in cancer. However, it is unknown whether the pathway blockade required for tumor growth inhibition is clinically achievable. Therefore, we conducted pharmacodynamic studies with GDC-0068, an ATP competitive, selective Akt1/2/3 inhibitor, in preclinical models and in patients treated with this compound. Experimental Design: We used a reverse phase protein array (RPPA) platform to identify a biomarker set indicative of Akt inhibition in cell lines and human-tumor xenografts, and correlated the degree of pathway inhibition with antitumor activity. Akt pathway activity was measured using this biomarker se…
A First-in-Human Phase I Study of the ATP-Competitive AKT Inhibitor Ipatasertib Demonstrates Robust and Safe Targeting of AKT in Patients with Solid Tumors.
Abstract Activation of AKT signaling by PTEN loss or PIK3CA mutations occurs frequently in human cancers, but targeting AKT has been difficult due to the mechanism-based toxicities of inhibitors that target the inactive conformation of AKT. Ipatasertib (GDC-0068) is a novel selective ATP-competitive small-molecule inhibitor of AKT that preferentially targets active phosphorylated AKT (pAKT) and is potent in cell lines with evidence of AKT activation. In this phase I study, ipatasertib was well tolerated; most adverse events were gastrointestinal and grade 1–2 in severity. The exposures of ipatasertib ≥200 mg daily in patients correlated with preclinical TGI90, and pharmacodynamic studies co…