Andrew Foxley

AKT Inhibition in Solid Tumors With AKT1 Mutations

Purpose AKT1 E17K mutations are oncogenic and occur in many cancers at a low prevalence. We performed a multihistology basket study of AZD5363, an ATP-competitive pan-AKT kinase inhibitor, to determine the preliminary activity of AKT inhibition in AKT-mutant cancers. Patients and Methods Fifty-eight patients with advanced solid tumors were treated. The primary end point was safety; secondary end points were progression-free survival (PFS) and response according to Response Evaluation Criteria in Solid Tumors (RECIST). Tumor biopsies and plasma cell-free DNA (cfDNA) were collected in the majority of patients to identify predictive biomarkers of response. Results In patients with AKT1 E17K-mutant tumors (n = 52) and a median of five lines of prior therapy, the median PFS was 5.5 months (95% CI, 2.9 to 6.9 months), 6.6 months (95% CI, 1.5 to 8.3 months), and 4.2 months (95% CI, 2.1 to 12.8 months) in patients with estrogen receptor-positive breast, gynecologic, and other solid tumors, respectively. In an exploratory biomarker analysis, imbalance of the AKT1 E17K-mutant allele, most frequently caused by copy-neutral loss-of-heterozygosity targeting the wild-type allele, was associated with longer PFS (hazard ratio [HR], 0.41; P = .04), as was the presence of coincident PI3K pathway hotspot mutations (HR, 0.21; P = .045). Persistent declines in AKT1 E17K in cfDNA were associated with improved PFS (HR, 0.18; P = .004) and response ( P = .025). Responses were not restricted to patients with detectable AKT1 E17K in pretreatment cfDNA. The most common grade ≥ 3 adverse events were hyperglycemia (24%), diarrhea (17%), and rash (15.5%). Conclusion This study provides the first clinical data that AKT1 E17K is a therapeutic target in human cancer. The genomic context of the AKT1 E17K mutation further conditioned response to AZD5363.

Abstract CT010: Phase I trial combining the PARP inhibitor olaparib (Ola) and AKT inhibitor AZD5363 (AZD) in germline (g)BRCA and non-BRCA mutant (m) advanced cancer patients (pts) incorporating noninvasive monitoring of cancer mutations

Background: Preclinical synergy between PARP and PI3K pathway inhibition in BRCA m and sporadic cancers provided rationale for this trial. Methods: Ola 300mg BID was combined with 2 schedules of AZD BID: 4 days on 3 days off (4/7) and 2 days on 5 days off (2/7) using a novel intrapatient dose escalation design (Michalarea et al, AACR 2015). Cohort expansion of pts with gBRCA m tumors and sporadic tumors with relevant somatic mutations or BRCAness phenotype, assessed 2 regimens: (1) 300mg BID Ola + 400mg BID 4/7 AZD and (2) 300mg BID Ola + 640mg BID 2/7 AZD. Targeted next generation sequencing (NGS) of tumor and cell-free (cf)DNA from 3-weekly plasma samples with a 113 gene panel was undertaken in all pts. Results: 53 pts with advanced cancers (21 gBRCA m) were enrolled (20 in dose escalation; 33 in dose expansion), including ovarian (9/19 with BRCA m), breast (8/16 with BRCA m), prostate (3/4 with BRCA m) and bile duct (1/2 with BRCA m) cancers. Common G1-2 toxicities were nausea, fatigue, anemia, diarrhea, anorexia, mucositis and vomiting on both schedules. 1 dose limiting toxicity (DLT) of G3 rash was seen at 300mg BID Ola + 480mg BID 4/7 AZD. In 4/7 schedule (n = 23), non-DLT G3 toxicities were anemia (n = 3), diarrhea, vomiting and proteinuria (all n = 1). In 2/7 schedule (n = 30), non-DLT G3 toxicities were transaminitis, nausea, fatigue, anemia (all n = 2), rash, hyperglycemia and diarrhea (all n = 1). There were 10 RECIST complete or partial responses (CR/PR) out of 37 (15 BRCA m) evaluable pts, including gBRCA m breast (n = 4), platinum-resistant gBRCA m ovarian (n = 2), BRCA wildtype (WT) triple negative breast (n = 1), BRCA WT ovarian (n = 2) and BRCA unknown prostate (n = 1) cancer pts. A BRCA1 m prostate cancer pt has MRI and PSA responses for 21mths+. A PI3K/mTOR inhibitor resistant peritoneal mesothelioma pt had CA125 response and RECIST stable disease (SD) for 21m. Of 5 ovarian cancer pts who had prior PARP inhibitors, 1 pt had RECIST PR at 13wks+ and 2 pts had SD with tumor shrinkage (18 and 24 wks). 160 cfDNA samples from 38 pts underwent NGS (minimum coverage 500X). Driver mutations were detected and tracked from baseline in 28 (76%) pts. Concordance in mutation status between tumor and cfDNA was 100% in 24/28 (86%) pts. 70% of pts had DNA repair gene mutations, most frequently BRCA. TP53 (40%) and KRAS (25%) were the most commonly detected somatic mutations. Changes in cfDNA concentrations appeared to correlate with treatment response in 72% of pts, while tracking of mutation allele frequency in serial cfDNA samples during treatment showed potential clonal responses. Conclusion: The combination of Ola and AZD is well tolerated with multiple responses in both gBRCA and non-BRCA m tumors, and prior PARP inhibitor treated cancers. The recommended phase 2 doses are 300mg BID Ola + 400mg BID 4/7 AZD and 300mg BID Ola + 640mg BID 2/7 AZD. Citation Format: Vasiliki Michalarea, Desam Roda, Yvette Drew, Suzanne Carreira, Brent S. O’Carrigan, Heather Shaw, Rene Roux, Sanjeev Kumar, Sarah Ward, Mona Parmar, Alison Turner, Emma Hall, Sonia Serrano Fandos, Raquel Perez, Nina Tunariu, Florence Raynaud, Marie Cullberg, Andrew Foxley, Justin PO Lindemann, Martin Pass, Paul Rugman, Juanita S. Lopez, Udai Banerji, Bristi Basu, Ruth Plummer, Rebecca Kristeleit, Johann S. de Bono, Timothy A. Yap. Phase I trial combining the PARP inhibitor olaparib (Ola) and AKT inhibitor AZD5363 (AZD) in germline (g)BRCA and non-BRCA mutant (m) advanced cancer patients (pts) incorporating noninvasive monitoring of cancer mutations. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr CT010.

Abstract B109: AZD5363, a catalytic pan-Akt inhibitor, in Akt1 E17K mutation positive advanced solid tumors

This abstract has been withheld from publication due to its inclusion in the AACR-NCI-EORTC Molecular Targets Conference 2015 Official Press Program. It will be posted online at the time of its presentation in a press conference or in a session: 10:00 AM ET Saturday, November 7. Citation Format: David M. Hyman, Lillian Smyth, Philippe L. Bedard, Amit Oza, Emma Dean, Anne Armstrong, Joao Lima, Hideaki Bando, Peter Kabos, J. Alejandro Perez-Fidalgo, Kathleen Moore, Shannon N. Westin, Benoit You, Sarat Chandarlapaty, Leila Alland, Helen Ambrose, Andrew Foxley, Justin Lindemann, Martin Pass, Paul Rugman, Shaista Salim, Gaia Schiavon, Kenji Tamura, Jose Baselga, Udai Banerji. AZD5363, a catalytic pan-Akt inhibitor, in Akt1 E17K mutation positive advanced solid tumors. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2015 Nov 5-9; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2015;14(12 Suppl 2):Abstract nr B109.

A Phase I Open-Label Study to Identify a Dosing Regimen of the Pan-AKT Inhibitor AZD5363 for Evaluation in Solid Tumors and in PIK3CA-Mutated Breast and Gynecologic Cancers

Purpose: This phase I, open-label study (Study 1, D3610C00001; NCT01226316) was the first-in-human evaluation of oral AZD5363, a selective pan-AKT inhibitor, in patients with advanced solid malignancies. The objectives were to investigate the safety, tolerability, and pharmacokinetics of AZD5363, define a recommended dosing schedule, and evaluate preliminary clinical activity. Experimental Design: Patients were aged ≥18 years with World Health Organization (WHO) performance status of 0 to 1. Dose escalation was conducted within separate continuous and intermittent [4 days/week (4/7) or 2 days/week (2/7)] schedules with safety, pharmacokinetic, and pharmacodynamic analyses. Expansion cohorts of approximately 20 patients each explored AZD5363 activity in PIK3CA-mutant breast and gynecologic cancers. Results: MTDs were 320, 480, and 640 mg for continuous (n = 47), 4/7 (n = 21), and 2/7 (n = 22) schedules, respectively. Dose-limiting toxicities were rash and diarrhea for continuous, hyperglycemia for 2/7, and none for 4/7. Common adverse events were diarrhea (78%) and nausea (49%) and, for Common Terminology Criteria for Adverse Events grade ≥3 events, hyperglycemia (20%). The recommended phase II dose (480 mg bid, 4/7 intermittent) was assessed in PIK3CA-mutant breast and gynecologic expansion cohorts: 46% and 56% of patients, respectively, showed a reduction in tumor size, with RECIST responses of 4% and 8%. These responses were less than the prespecified 20% response rate; therefore, the criteria to stop further recruitment to the PIK3CA-mutant cohort were met. Conclusions: At the recommended phase II dose, AZD5363 was well tolerated and achieved plasma levels and robust target modulation in tumors. Proof-of-concept responses were observed in patients with PIK3CA-mutant cancers treated with AZD5363. Clin Cancer Res; 24(9); 2050–9. ©2017 AACR. See related commentary by Costa and Bosch, p. 2029

Abstract CT331: “BEECH”, a phase I/II study of the AKT inhibitor AZD5363 combined with paclitaxel in patients with advanced or metastatic breast cancer: results from the dose-finding study, including quantitative assessment of circulating tumor DNA as a s

Background: The PI3K/AKT/MTOR pathway is frequently de-regulated in breast cancer. AZD5363 (AZD) is a potent selective inhibitor of AKT1-3. We report the dose-finding phase assessing the safety/tolerability of two intermittent weekly dosing schedules of AZD combined with paclitaxel (P) in HER2 negative breast cancer. The study incorporates prospective assessment of whether circulating tumour DNA (ctDNA) analysis can predict response/resistance earlier than conventional RECIST. Design: AZD capsules were dosed p.o. in one of two schedules: “4/3” (4 days on-treatment followed by 3 days off, starting 360 mg twice daily (bd)) or “2/5” (2 days on-5 days off, starting 560 mg bd). Both schedules comprised 3 weeks P 90 mg/m2 IV on Day 1 with AZD started on Day 2, and 1 week off-treatment. Patients who stopped P were able to continue AZD alone at investigators’ discretion. Escalating doses of AZD were evaluated in cohorts of 3-6 evaluable patients treated until disease progression, unacceptable toxicity, or withdrawal of consent. A safety review committee reviewed safety data and dose limiting toxicities (DLTs) prior to dose modification. Plasma samples for ctDNA extraction were collected at baseline, weekly in cycle 1, day 1 of all subsequent cycles, and were analysed by digital PCR. Female patients aged ≥18 years with HER2 negative MBC and up to two prior chemotherapy courses for advanced cancer were recruited. Results: 37 patients have received AZD. DLTs in 2/6 patients at 480 mg 4/3 comprised one patient with maculo-papular rash, and another with immune allergic reaction (both CTCAE grade 3). No DLT was observed in the 400 mg 4/3 cohort, which was defined as the maximum tolerated dose (MTD) in combination with P. DLTs in 2/6 patients at 640 mg 2/5 comprised one patient with prolonged neutropaenia (grade 4), and another with diarrhoea (grade 3). No DLTs were observed in 11 patients on the 560 mg 2/5 cohort. In all patients median progression free survival was 8.2 months, despite pre-treatment with taxane chemotherapy in 62% patients and a median of 2 prior lines of chemotherapy. A patient with Cowden9s syndrome (PTEN germline mutation) had a partial response maintained for 18 months, including 12 months on AZD5363 alone. ctDNA assessment suggests that lack of a fall in ctDNA abundance may predict for early progression. Conclusions: AZD5363 400mg bd 4/3 in combination with paclitaxel was determined to be well tolerated in patients with MBC, with investigation of the 2/5 schedule continuing. Two international double-blind randomised studies have commenced to assess AZD5363 400 mg bd 4/3 schedule combined with paclitaxel versus paclitaxel plus placebo in ER positive HER2 negative MBC stratified by PIK3CA mutation status (BEECH Part B), and in triple negative breast cancer (PAKT). Citation Format: Nicholas C. Turner, Mafalda Oliveira, Anne Armstrong, Marie-Paule Sablin, Jose A. Perez-Fidalgo, Sarah Herebien, Isaac Garcia-Murillas, Stan Johnson, Andrew Foxley, Adnan Mahmood, Justin P. Lindemann. “BEECH”, a phase I/II study of the AKT inhibitor AZD5363 combined with paclitaxel in patients with advanced or metastatic breast cancer: results from the dose-finding study, including quantitative assessment of circulating tumor DNA as a s [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr CT331. doi:10.1158/1538-7445.AM2015-CT331