Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
1,770
result(s) for
"Class I Phosphatidylinositol 3-Kinases"
Sort by:
Therapeutic implications of activating noncanonical PIK3CA mutations in head and neck squamous cell carcinoma
2021
Alpelisib selectively inhibits the p110α catalytic subunit of PI3Kα and is approved for treatment of breast cancers harboring canonical PIK3CA mutations. In head and neck squamous cell carcinoma (HNSCC), 63% of PIK3CA mutations occur at canonical hotspots. The oncogenic role of the remaining 37% of PIK3CA noncanonical mutations is incompletely understood. We report a patient with HNSCC with a noncanonical PIK3CA mutation (Q75E) who exhibited a durable (12 months) response to alpelisib in a phase II clinical trial. Characterization of all 32 noncanonical PIK3CA mutations found in HNSCC using several functional and phenotypic assays revealed that the majority (69%) were activating, including Q75E. The oncogenic impact of these mutations was validated in 4 cellular models, demonstrating that their activity was lineage independent. Further, alpelisib exhibited antitumor effects in a xenograft derived from a patient with HNSCC containing an activating noncanonical PIK3CA mutation. Structural analyses revealed plausible mechanisms for the functional phenotypes of the majority of the noncanonical PIK3CA mutations. Collectively, these findings highlight the importance of characterizing the function of noncanonical PIK3CA mutations and suggest that patients with HNSCC whose tumors harbor activating noncanonical PIK3CA mutations may benefit from treatment with PI3Kα inhibitors.
Journal Article
Inavolisib-Based Therapy in PIK3CA-Mutated Advanced Breast Cancer
by
Turner, Nicholas C.
,
Schutzman, Jennifer L.
,
Leung, Roland
in
1-Phosphatidylinositol 3-kinase
,
Adjuvants
,
Adult
2024
In
PIK3CA
-mutated, HR-positive, HER2-negative locally advanced or metastatic breast cancer, inavolisib plus palbociclib–fulvestrant led to significantly longer progression-free survival than placebo plus palbociclib–fulvestrant.
Journal Article
Overall Survival with Inavolisib in PIK3CA-Mutated Advanced Breast Cancer
by
Turner, Nicholas C.
,
Thanopoulou, Eirini
,
Song, Chunyan
in
Adult
,
Aged
,
Antineoplastic Combined Chemotherapy Protocols - administration & dosage
2025
In patients with
PIK3CA
-mutated advanced breast cancer, inavolisib added to palbociclib–fulvestrant led to a significant overall survival benefit, with a higher incidence of certain toxic effects than placebo.
Journal Article
Early circulating tumor DNA dynamics and clonal selection with palbociclib and fulvestrant for breast cancer
by
Turner, Nicholas C.
,
Bliss, Judith M.
,
Hrebien, Sarah
in
45/77
,
692/4028/67/1347
,
692/4028/67/1857
2018
CDK4/6 inhibition substantially improves progression-free survival (PFS) for women with advanced estrogen receptor-positive breast cancer, although there are no predictive biomarkers. Early changes in circulating tumor DNA (ctDNA) level may provide early response prediction, but the impact of tumor heterogeneity is unknown. Here we use plasma samples from patients in the randomized phase III PALOMA-3 study of CDK4/6 inhibitor palbociclib and fulvestrant for women with advanced breast cancer and show that relative change in
PIK3CA
ctDNA level after 15 days treatment strongly predicts PFS on palbociclib and fulvestrant (hazard ratio 3.94, log-rank
p
= 0.0013).
ESR1
mutations selected by prior hormone therapy are shown to be frequently sub clonal, with
ESR1
ctDNA dynamics offering limited prediction of clinical outcome. These results suggest that early ctDNA dynamics may provide a robust biomarker for CDK4/6 inhibitors, with early ctDNA dynamics demonstrating divergent response of tumor sub clones to treatment.
Circulating tumor DNA (ctDNA) may provide a prediction of treatment response, but could be impacted by tumor heterogeneity. Here, the authors investigate ctDNA in CDK4/6 inhibitor treatment in advanced breast cancer, finding ctDNA levels predict progression-free survival and anticipate clonal selection.
Journal Article
Heterogeneity and clinical significance of ESR1 mutations in ER-positive metastatic breast cancer patients receiving fulvestrant
2016
Mutations in
ESR1
have been associated with resistance to aromatase inhibitor (AI) therapy in patients with ER+ metastatic breast cancer. Little is known of the impact of these mutations in patients receiving selective oestrogen receptor degrader (SERD) therapy. In this study, hotspot mutations in
ESR1
and
PIK3CA
from ctDNA were assayed in clinical trial samples from ER+ metastatic breast cancer patients randomized either to the SERD fulvestrant or fulvestrant plus a pan-PI3K inhibitor.
ESR1
mutations are present in 37% of baseline samples and are enriched in patients with luminal A and
PIK3CA
-mutated tumours.
ESR1
mutations are often polyclonal and longitudinal analysis shows distinct clones exhibiting divergent behaviour over time.
ESR1
mutation allele frequency does not show a consistent pattern of increases during fulvestrant treatment, and progression-free survival is not different in patients with
ESR1
mutations compared with wild-type patients.
ESR1
mutations are not associated with clinical resistance to fulvestrant in this study.
Fulvestrant degrades the oestrogen receptor. Here, the authors report on a clinical trial using fulvestrant and show that mutations in the oestrogen receptor alpha gene are prevalent in circulating tumour DNA and do not influence the clinical outcome of patients to fulvestrant.
Journal Article
Comparison of BEAMing and Droplet Digital PCR for Circulating Tumor DNA Analysis
2019
Circulating tumor DNA (ctDNA) assays are increasingly used for clinical decision-making, but it is unknown how well different assays agree. We aimed to assess the agreement in ctDNA mutation calling between BEAMing (beads, emulsion, amplification, and magnetics) and droplet digital PCR (ddPCR), 2 of the most commonly used digital PCR techniques for detecting mutations in ctDNA.
Baseline plasma samples from patients with advanced breast cancer enrolled in the phase 3 PALOMA-3 trial were assessed for
and
mutations in ctDNA with both BEAMing and ddPCR. Concordance between the 2 approaches was assessed, with exploratory analyses to estimate the importance of sampling effects.
Of the 521 patients enrolled, 363 had paired baseline ctDNA analysis.
mutation detection was 24.2% (88/363) for BEAMing and 25.3% (92/363) for ddPCR, with good agreement between the 2 techniques (κ = 0.9l; 95% CI, 0.85-0.95).
mutation detection rates were 26.2% (95/363) for BEAMing and 22.9% (83/363) for ddPCR, with good agreement (κ = 0.87; 95% CI, 0.81-0.93). Discordancy was observed for 3.9% patients with
mutations and 5.0% with
mutations. Assessment of individual mutations suggested higher rates of discordancy for less common mutations (
= 0.019). The majority of discordant calls occurred at allele frequency <1%, predominantly resulting from stochastic sampling effects.
This large, clinically relevant comparison showed good agreement between BEAMing and ddPCR, suggesting sufficient reproducibility for clinical use. Much of the observed discordancy may be related to sampling effects, potentially explaining many of the differences in the currently available ctDNA literature.
Journal Article
Predicting and Confirming Bioequivalence of Alpelisib Oral Granules and Tablets for Patients With PIK3CA-Related Disorders
by
Ren, Xiaojun
,
Garbuio, Luca
,
Burmeister Getz, Elise
in
1-Phosphatidylinositol 3-kinase
,
Administration, Oral
,
Adolescent
2025
Alpelisib, an oral α-specific phosphoinositide 3-kinase (
PI3K
) inhibitor, has been shown to be safe and effective for some patients with gain-of-function mutation in the
PIK3CA
oncogene. Alpelisib has received US FDA accelerated approval as Vijoice® film-coated tablets to treat severe
PIK3CA
-Related Overgrowth Spectrum (PROS). PROS typically displays clinical manifestations in the first year of patient life. Therefore, oral granules were developed as an age-appropriate pediatric dosage form. Bioequivalence between alpelisib granules and tablet and the effect of food on granules pharmacokinetics were assessed in a single-center, randomized, three-treatment, six-sequence, three-period, crossover study among 60 healthy adults. Participants were randomly assigned to receive a single 50-mg alpelisib dose as:
(i)
tablet following a meal,
(ii)
granules following a meal, and
(iii)
granules while fasting. Statistical analysis of non-compartmental pharmacokinetic parameters demonstrated bioequivalence between the 50-mg alpelisib granules and tablet forms when administered with food: estimated geometric mean ratios (90% confidence interval) for granules-versus-tablet area under the curve (AUC) from time zero to infinity (AUC
inf
), to the last measurable concentration (AUC
last
) and maximum observed concentration (C
max
) were 0.984 (0.952, 1.02), 0.980 (0.946, 1.02), and 0.947 (0.891, 1.01), respectively. No clinically relevant food effect on 50-mg alpelisib granules pharmacokinetics was observed. These results were accurately predicted using physiologically based biopharmaceutical modeling. Alpelisib granules provide a bioequivalent alternative to tablets for patients prescribed a 50-mg dose and have difficulty swallowing tablets, an important consideration for convenience and compliance of this standard-of-care chronic therapy for patients with PROS. This study was registered in ClinicalTrials.gov on January 4, 2022 (NCT05195892).
Graphical Abstract
Journal Article
Capivasertib plus fulvestrant in patients with HR-positive/HER2-negative advanced breast cancer: phase 3 CAPItello-291 study extended Chinese cohort
2025
In the global CAPItello-291 randomized phase 3 study (NCT04305496) in patients with hormone receptor-positive/HER2-negative advanced breast cancer and progression during/after aromatase inhibitor treatment, capivasertib–fulvestrant significantly improved progression-free survival (PFS) in the overall population and patients with
PIK3CA/AKT1/PTEN
-altered tumors versus placebo–fulvestrant. We assessed efficacy and safety of capivasertib–fulvestrant in a prespecified exploratory analysis of a Chinese cohort (
n
= 24) and extended study with the same protocol (
n
= 110). Clinically meaningful PFS benefit for capivasertib–fulvestrant was observed in the overall population (median PFS: 6.9 [capivasertib–fulvestrant] versus 2.8 [placebo–fulvestrant] months; hazard ratio 0.51, 95% CI 0.34–0.76), patients with
PIK3CA/AKT1/PTEN
-altered tumors (
n
= 46; 5.7 versus 1.9 months; hazard ratio 0.41, 95% CI 0.19–0.85) and
PIK3CA/AKT1/PTEN
-non-altered tumors (patients with confirmed next-generation sequencing results [
n
= 68]; 9.2 versus 2.7 months; hazard ratio 0.38; 95% CI 0.21–0.68). The most frequent adverse events (AEs) with capivasertib–fulvestrant were diarrhea (60.6% versus 11.3% with placebo–fulvestrant) and hyperglycemia (57.7% versus 17.7%). AEs leading to capivasertib–fulvestrant discontinuation were reported in 11.3% of patients versus 3.2% for placebo–fulvestrant. The benefit-risk profile of capivasertib–fulvestrant in the Chinese cohort was favorable; further exploration in patients with
PIK3CA/AKT1/PTEN
-non-altered tumors is warranted.
The CAPItello-291 phase 3 study reported that capivasertib (an AKT inhibitor) and fulvestrant (a selective estrogen receptor degrader) improved progression free survival in patients with HR-positive/HER2-negative advanced breast cancer. Here, the authors report the results of an extended Chinese cohort recruited as part of the original global CAPItello-291 study.
Journal Article
CHF6523 data suggest that the phosphoinositide 3-kinase delta isoform is not a suitable target for the management of COPD
by
Korn, Stephanie
,
Kornmann, Oliver
,
Watz, Henrik
in
1-Phosphatidylinositol 3-kinase
,
Administration, Inhalation
,
Aged
2024
Background
Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory condition. Given patients with COPD continue to experience exacerbations despite the availability of effective therapies, anti-inflammatory treatments targeting novel pathways are needed. Kinases, notably the phosphoinositide 3-kinases (PI3K), are thought to be involved in chronic airway inflammation, with this pathway proposed as a critical regulator of inflammation and oxidative stress response in COPD. CHF6523 is an inhaled PI3Kδ inhibitor that has shown positive preclinical results. This manuscript reports the results of a study of CHF6523 in patients with stable COPD (chronic bronchitis phenotype), and who had evidence of type-2 inflammation.
Methods
This randomised, double-blind, placebo-controlled, two-way crossover study comprised two 28-day treatment periods separated by a 28-day washout. Patients (
N
= 44) inhaled CHF6523 in one period, and placebo in the other, both twice daily. The primary objective was to assess the safety and tolerability of CHF6523; the secondary objective was to assess CHF6523 pharmacokinetics. Exploratory endpoints included target engagement (the relative reduction in phosphatidylinositol (3,4,5)-trisphosphate [PIP
3
]), pharmacodynamic evaluations such as airflow obstruction, and hyperinflation, and to identify biomarker(s) of drug response using proteomics and transcriptomics.
Results
CHF6523 plasma pharmacokinetics were characterised by an early maximum concentration (C
max
), reached 15 and 10 min after dosing on Days 1 and 28, respectively, followed by a rapid decline. Systemic exposure on Day 28 showed limited accumulation, with ratios < 1.6 for C
max
and area under the curve from 0 to 12 h post-dose, and with steady state achieved on Day 20. Target engagement was confirmed by a significant 29.7% reduction from baseline in induced sputum PIP
3
(29.5% reduction vs. placebo; adjusted ratio 0.705 [0.580, 0.856];
p
= 0.001), but this did not translate into an anti-inflammatory pharmacodynamic effect, as assessed through measures including biomarkers and multi-omics. Additionally, although CHF6523 was generally well-tolerated, 95.2% of patients reported cough as an adverse event, most mild to moderate and resolving within one-hour post-dose.
Conclusions
These data, together with those from other PI3K inhibitors, suggest that PI3Kδ is not a suitable pathway for the management of COPD, as the achieved target engagement did not translate into any pharmacodynamic anti-inflammatory effect.
Trial registration
ClinicalTrials.gov (NCT04032535); posted 23rd July 2019.
Journal Article
Alpelisib for PIK3CA-Mutated, Hormone Receptor–Positive Advanced Breast Cancer
2019
PIK3CA
mutations occur in approximately 40% of patients with hormone receptor–positive breast cancer. A PI3K inhibitor, alpelisib, combined with fulvestrant led to a median progression-free survival of 11 months, as compared with 5.7 months with placebo plus fulvestrant. Hyperglycemia, rash, and diarrhea were more common with alpelisib.
Journal Article