Dataset Information

Alpelisib: A Novel Therapy for Patients With PIK3CA-Mutated Metastatic Breast Cancer.

ABSTRACT: In the United States, 1 in 8 women will be diagnosed with invasive breast cancer in her lifetime. Breast cancer death rates are higher for women in the United States than any other cancer, followed by lung cancer (National Cancer Institute, 2019). More than 70% of breast cancers are hormone receptor (HR)-positive and human epidermal growth factor receptor 2 (HER2)-negative, and of those patients, 40% have driver mutations in the gene phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) resulting in damaged phosphatidylinositol 3-kinase (PI3K) and uncontrolled cell growth (Mollon et al., 2018; Setiawan et al., 2009). These patients are initially treated with endocrine therapy, but resistance remains an issue. Inhibition of PI3K is a promising new approach to overcome resistance to endocrine therapy in breast cancer. Previous trials of PI3K inhibitors (pictilisib [GDC-0941], buparlisib [BMK120], and taselisib [GDC-0032]) in breast cancer have shown little efficacy secondary to toxicities due to their nonselectivity to PI3K subunits. Alpelisib is a selective inhibitor of PI3K for patients with HR-positive, HER2-negative, PIK3CA-mutated breast cancer who have progressed on endocrine therapy. This drug review will discuss the pharmacology of alpelisib, current data supporting its place in therapy, management of adverse events, and the clinical implications for advanced practitioners treating patients with HR-positive, HER2-negative breast cancer.

SUBMITTER: Wilhoit T

PROVIDER: S-EPMC7646628 | biostudies-literature | 2020 Sep-Oct

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Alpelisib: A Novel Therapy for Patients With <i>PIK3CA-</i>Mutated Metastatic Breast Cancer.

Wilhoit Tori T Patrick Jeannie M JM May Megan B MB

Journal of the advanced practitioner in oncology 20200901 7

In the United States, 1 in 8 women will be diagnosed with invasive breast cancer in her lifetime. Breast cancer death rates are higher for women in the United States than any other cancer, followed by lung cancer (National Cancer Institute, 2019). More than 70% of breast cancers are hormone receptor (HR)-positive and human epidermal growth factor receptor 2 (HER2)-negative, and of those patients, 40% have driver mutations in the gene phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subun ...[more]

PMID: 33575071

Similar Datasets

Project description:BackgroundThe BYLieve trial (NCT03056755) confirmed efficacy and safety of alpelisib with fulvestrant for hormone receptor-positive (HR+), human epidermal growth factor receptor-2-negative (HER2-), PIK3CA-mutated advanced breast cancer (ABC), after cyclin-dependent kinase 4/6 inhibitor (CDK4/6i) with an aromatase inhibitor (AI) as immediate prior therapy. Further analyses were performed to compare efficacy from BYLieve with effectiveness of standard treatment in the real-world setting.Materials and methodsPatients who progressed on a CDK4/6i plus AI and were treated with alpelisib with fulvestrant in BYLieve were matched with a real-world patient cohort who received standard-of-care from a deidentified clinico-genomics database (CGDB). Primary and secondary endpoints were to compare progression-free survival (PFS), estimated by the Kaplan-Meier method, and the proportion of patients remaining progression-free at 6 months, respectively, between the two cohorts.ResultsA total of 855 patients with PIK3CA-mutant disease who had prior CDK4/6i plus hormone therapy were selected from the CGDB; further matching to 120 patients from BYLieve selected 95 patients without exposure to HER2-targeting agents, clinical study drug, or alpelisib. In unadjusted and postmatching results, primary and secondary endpoints favored treatment with alpelisib with fulvestrant in BYLieve more than standard treatments in the real-world cohort. Postadjustment, median PFS for patients treated with alpelisib in BYLieve was 7.3 versus 3.7 months in the real-world cohort, and 6-month PFS was 54.6% versus 40.1%, respectively.ConclusionMatched/weighted analysis comparing BYLieve with the real-world setting further supports the clinical benefit of alpelisib with fulvestrant for treatment of HR+, HER2-, PIK3CA-mutant ABC after CDK4/6i treatment.Implications for practiceApproximately 40% of patients with hormone receptor-positive (HR+), human epidermal growth factor receptor-2-negative (HER2-) advanced breast cancer (ABC) have PIK3CA-mutated tumors, which have been associated with endocrine therapy resistance. Alpelisib, an α-selective phosphatidylinositol-3-kinase inhibitor, demonstrated significantly improved progression-free survival in SOLAR-1 and demonstrated clinical efficacy in BYLieve when combined with fulvestrant. Data are limited in comparing the efficacy of alpelisib combined with fulvestrant with effectiveness of standard therapy after CDK4/6i treatment. Using real-world data, this is the first analysis comparing alpelisib combined with fulvestrant with standard treatments for HR+, HER2-, PIK3CA-mutant ABC in the post-CDK4/6i setting.

Project description:The PI3K/AKT/mTOR pathway has long been known to play a major role in the growth and survival of cancer cells. Breast tumors often harbor PIK3CA gene alterations, which therefore constitute a rational drug target. However, it has taken many years to demonstrate clinically-relevant efficacy of PI3K inhibition and eventually attain regulatory approvals. As data on PI3K inhibitors continue to mature, this review updates and summarizes the current state of the science, including the prognostic role of PIK3CA alterations in breast cancer; the evolution of PI3K inhibitors; the clinical utility of the first-in-class oral selective PI3Kα inhibitor, alpelisib; PIK3CA mutation detection techniques; and adverse effect management. PIK3CA-mutated breast carcinomas predict survival benefit from PI3K inhibitor therapy. The pan-PI3K inhibitor, buparlisib and the beta-isoform-sparing PI3K inhibitor, taselisib, met efficacy endpoints in clinical trials, but pictilisib did not; moreover, poor tolerability of these three drugs abrogated further clinical trials. Alpelisib is better tolerated, with a more manageable toxicity profile; the principal adverse events, hyperglycemia, rash and diarrhea, can be mitigated by intensive monitoring and timely intervention, thereby enabling patients to remain adherent to clinically beneficial treatment. Alpelisib plus endocrine therapy shows promising efficacy for treating postmenopausal women with HR+/HER2- advanced breast cancer. Available evidence supporting using alpelisib after disease progression on first-line endocrine therapy with or without CDK4/6 inhibitors justifies PIK3CA mutation testing upon diagnosing HR+/HER2- advanced breast cancer, which can be done using either tumor tissue or circulating tumor DNA. With appropriate toxicity management and patient selection using validated testing methods, all eligible patients can potentially benefit from this new treatment. Further clinical trials to assess combinations of hormone therapy with PI3K, AKT, mTOR, or CDK 4/6 inhibitors, or studies in men and women with other breast subtypes are ongoing.

Project description:BackgroundHER2 is amplified or overexpressed in around 20% of breast cancers (BC). HER2-targeted therapies have significantly improved the prognosis of patients with HER2+ BC, however, de novo and acquired resistance to anti-HER2 treatment is common. Activating mutations in the PIK3CA gene are reported in ∼30% of HER2+ BC and are associated with resistance to anti-HER2 therapies and a poor prognosis. Here, we investigated the in vitro and in vivo antitumor efficacy of the alpha-specific PI3K inhibitor alpelisib alone or in combination with anti-HER2 therapy using a panel of HER2+ BC cell lines. We also generated models of acquired resistance to alpelisib to investigate the mechanisms underlying resistance to alpha-specific PI3K inhibition.Materials and methodsPIK3CA mutant (HCC1954, KPL4 and JMT1) and wild-type (BT474 and SKBR3) HER2+ BC cell lines were used. The HCC1954 and KPL4 cells were chronically exposed to increasing concentrations of alpelisib or to alpelisib + trastuzumab in order to generate derivatives with acquired resistance to alpelisib (AR) and to alpelisib + trastuzumab (ATR). The transcriptomic profiles of HCC1954, KPL4 and their AR and ATR derivatives were determined by RNA sequencing. Cell growth was assessed by MTT assay. Changes in the protein levels of key PI3K pathway components were assessed by Western blotting. Gene expression, cellular and patients' data from the Cancer Dependency Map (DepMap) and KMPlot datasets were interrogated.ResultsHER2+ BC cell lines harboring activating mutations in PIK3CA were less sensitive to single or dual anti-HER2 blockade compared to PIK3CA wild-type cells. Alpelisib treatment resulted in dose-dependent inhibition of the growth of cells with or without PIK3CA mutations and enhanced the antitumor efficacy of anti-HER2 therapies in vitro. In addition, alpelisib greatly delayed tumor growth of HCC1954 xenografts in vivo. Functional annotation of the significantly differentially expressed genes suggested the common activation of biological processes associated with oxidation reduction, cell proliferation, immune response and RNA synthesis in alpelisib-resistant models compared with native cells. Eight commonly upregulated genes (log2 fold-change >1, False Discovery Rate [FDR] <0.05) in models with acquired resistance to alpelisib or alpelisib + trastuzumab were identified. Among these, AKR1C1 was associated with alpelisib-resistance in vitro and with a poor prognosis in patients with HER2+ BC.ConclusionsOur findings support the use of an alpha-selective PI3K inhibitor to overcome the therapeutic limitations associated with single or dual HER2 blockade in PIK3CA-mutant HER2+ breast cancer. Future studies are warranted to confirm the potential role of candidate genes/pathways in resistance to alpelisib.

Project description:ImportanceThe phosphatidylinositol 3-kinase (PI3K) pathway is frequently activated in patients with estrogen receptor-positive (ER+), endocrine therapy-resistant breast cancers.ObjectiveTo 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 participantsAn 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.InterventionsEscalating 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 measuresThe primary end point was determination of the MTD of once-daily alpelisib plus fulvestrant. Secondary end points included safety and preliminary activity.ResultsFrom 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 relevanceAlpelisib 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 registrationClinicalTrials.gov identifier: NCT01219699.

Dataset Information

Alpelisib: A Novel Therapy for Patients With PIK3CA-Mutated Metastatic Breast Cancer.

Publications

Alpelisib: A Novel Therapy for Patients With <i>PIK3CA-</i>Mutated Metastatic Breast Cancer.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets