Dermatologic adverse events related to the PI3Kα inhibitor alpelisib (BYL719) in patients with breast cancer

Targeting STAT3 for Cancer Therapy: Focusing on Y705, S727, or Dual Inhibition?

BACKGROUND/OBJECTIVES

Signal Transducer and Activator of Transcription 3 (STAT3) is a transcription factor that is strongly implicated in various cancers. In its canonical signaling pathway, Janus kinases (JAKs) phosphorylate STAT3 at the Y705 residue in response to cytokines or growth factors, with pY705 serving as a key marker of STAT3 oncogenic activity. Elevated pY705 levels correlate with poor prognosis, and numerous small-molecule inhibitors have been developed to block this phosphorylation site. More recently, phosphorylation at the S727 residue (pS727) has emerged as a critical contributor to STAT3-mediated oncogenesis, particularly due to its role in mitochondrial translocation. Evidence suggests that pS727 may even surpass pY705 in driving oncogenic activity. These findings prompt an important question: Which residue should be prioritized for effective STAT3 inhibition in cancer therapy?

METHODS

This review compiles and critically analyzes the current literature on STAT3 inhibitors targeting pY705 and/or pS727, evaluating their therapeutic efficacy in vitro, in vivo, and in clinical trials. We assess the unique effects of targeting each residue on downstream signaling, toxicity, and clinical outcomes.

RESULTS

Our analysis indicates that inhibitors targeting both pY705 and pS727 achieve the greatest therapeutic effectiveness. However, pS727 targeting is associated with higher toxicity risks.

CONCLUSIONS

Comprehensive evaluation of STAT3 inhibitors underscores the importance of targeting pY705 for maximum therapeutic benefit. The analysis also shows that co-targeting pS727 may increase overall efficacy. However, pS727 inhibition should be approached with lower affinity to minimize toxicity and enhance the clinical feasibility of dual-targeting strategies.

Synthesis of thiazole-integrated pyrrolotriazinones: evaluations of cytotoxicity and effects on PI3K levels in cancer cells

The synthesis of novel heterocyclic compounds, particularly those targeting critical signaling pathways in cancer, represents a promising approach to drug development. In this study, we designed and synthesized a series of thiazole-integrated pyrrolotriazinone derivatives, aiming to combine the antiproliferative properties of thiazole with the PI3K inhibitory activity of pyrrolotriazinones. The PI3K pathway, which plays a critical role in regulating cell growth, proliferation, and survival, is frequently dysregulated in cancer, making it an attractive target for therapeutic intervention. The synthesized derivatives were evaluated for their cytotoxic activities against MCF-7, A549, and HepG2 cancer cell lines. Their effect on PI3K protein levels was assessed to evaluate their potential as PI3K inhibitors. Preliminary results indicate that these thiazole-pyrrolotriazinone hybrids exhibit significant cytotoxic effects and may reduce PI3K protein levels in cancer cells. Furthermore, drug-likeness assessments and pre-ADMET evaluations demonstrated that the compounds exhibited promising characteristics, supporting their potential as viable drug candidates. Overall, this study highlights the potential of these novel compounds in cancer therapy and provides valuable insights into the design of small molecules that can target key regulatory pathways involved in cancer progression.

Practical treatment strategies and novel therapies in the phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway in hormone receptor-positive/human epidermal growth factor receptor 2 (HER2)-negative (HR+/HER2-) advanced breast cancer

Mutations in the phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway occur in 30%-40% of patients with advanced hormone receptor-positive/human epidermal growth factor receptor 2 (HER2)-negative (HR+/HER2-) breast cancer. For most patients, endocrine therapy with a cyclin-dependent kinase 4/6 (CDK4/6) inhibitor is the first-line treatment. Recent studies indicate that adding inavolisib, a PI3Kα inhibitor, to palbociclib/fulvestrant benefits patients with endocrine-resistant HR+/HER2- metastatic breast cancer with a PIK3CA mutation. Alpelisib and capivasertib are both US Food and Drug Administration (FDA) approved in combination with fulvestrant in patients with endocrine-resistant HR+/HER2-, PIK3CA-mutant metastatic breast cancer, both with activity in the post-CDK4/6 setting. Capivasertib added to fulvestrant is the first AKT inhibitor to show a significant progression-free survival benefit with a trend for overall survival benefit and the only approved option for patients with phosphate and tensin homolog (PTEN) or AKT alterations. Toxicity profiles of all agents necessitate careful patient selection. Several mutant-selective and pan-mutant-selective novel inhibitors are under investigation with the potential to improve tolerability and efficacy.

Treatment-related adverse events in patients with advanced breast cancer receiving adjuvant AKT inhibitors: a meta-analysis of randomized controlled trials

INTRODUCTION

Incorporation of AKT inhibitors into adjuvant therapy for advanced or metastatic breast cancer has improved clinical outcomes. However, the safety of AKT inhibitors should be better evaluated, given the possibility of prolonging survival and impacting patient quality of life. Our aim was to assess how the addition of AKT inhibitors to adjuvant therapy affects treatment-related adverse events.

METHODS

We evaluated binary outcomes with risk ratios (RRs), with 95% confidence intervals (CIs). We used DerSimonian and Laird random-effect models for all endpoints. Heterogeneity was assessed using I2 statistics. R, version 4.2.3, was used for statistical analyses.

RESULTS

A total of seven RCTs comprising 1619 patients with BC. The adverse effects that show significance statistical favoring the occurrence of adverse effects in AKT inhibitor were diarrhea (RR 3.05; 95% CI 2.48-3.75; p < 0.00001; I2 = 49%), hyperglycemia (RR 3.4; 95% CI 1.69-6.83; p = 0.00058; I2 = 75%), nausea (RR 1.69; 95% CI 1.34-2.13; p = 0.000008; I2 = 42%), rash (RR 2.79; 95% CI 1.49-5.23; p = 0.0013; I2 = 82%), stomatitis (RR 2.24; 95% CI 1.69-2.97; p < 0.00001; I2 = 16%) and vomiting (RR 2.99; 95% CI 1.85-4.86; p = 0.00009; I2 = 42%). There was no significant difference between the groups for alopecia (p = 0.80), fatigue (p = 0.087), and neuropathy (p = 0.363380).

CONCLUSION

The addition of AKT inhibitors to adjuvant therapy was associated with an increase in treatment-related adverse events. These results provide safety information for further clinical trials evaluating AKT inhibitor therapy for patients with metastatic BC. Clinicians should closely monitor patients for treatment-related adverse events to avoid discontinuation of therapy and morbidity caused by these early-stage therapies.

Body composition measures as a determinant of Alpelisib related toxicity

BACKGROUND

Body composition has emerged as an important prognostic factor in patients treated with cancer. Severe depletion of skeletal muscle, sarcopenia, has been associated with poor performance status and worse oncological outcomes. We studied patients with metastatic breast cancer receiving alpelisib, to determine if sarcopenia and additional body composition measures accounting for muscle and adiposity are associated with toxicity.

METHODS

A retrospective observational analysis was conducted, including 38 women with metastatic breast cancer and a PIK3CA mutation, treated with alpelisib as advanced line of therapy. Sarcopenia was determined by measuring skeletal muscle cross-sectional area at the third lumbar vertebra using computerized tomography. Various body composition metrics were assessed along with drug toxicity, dose reductions, treatment discontinuation, hospitalizations, time to treatment failure and overall survival.

RESULTS

Sarcopenia was observed in half of the patients (n = 19, 50%), spanning normal weight, overweight, and obese individuals. Among the body composition measures, lower skeletal muscle density (SMD) was associated with an increased risk of treatment-related hyperglycaemia (P = 0.03). Additionally, lower visceral adipose tissue (VAT) was associated with alpelisib-induced rash (P = 0.04) and hospitalizations (P = 0.04). Notably, alpelisib treatment discontinuation was not impacted by alpelisib toxicity.

CONCLUSION

Body composition measures, specifically SMD and VAT may provide an opportunity to identify patients at higher risk for severe alpelisib related hyperglycemia, and cutaneous toxicity. These findings suggest the potential use of body composition assessment to caution toxicity risk, allowing for personalized therapeutic observation and intervention.

A real-world disproportionality analysis of FDA adverse event reporting system (FAERS) events for alpelisib

In this study, we delved into the safety profile of alpelisib, an FDA-approved treatment for hormone receptor-positive, HER2-negative, PIK3CA-mutated advanced or metastatic breast cancer, and PIK3CA-Related Overgrowth Spectrum (PROS). Despite its approval, real-world, long-term safety data is lacking. Our research scrutinizes the FDA database to assess alpelisib 's safety. We retrospectively analyzed data from April 2019 to June 2023 using four algorithms. Among 7,609,450 reports, 6692 implicated alpelisib as the primary suspected drug, uncovering adverse events (AEs) across 26 organ systems. Notably, we identified 21 previously unlisted AEs. Furthermore, differences in AEs emerged between patients with PIK3CA-mutated breast cancer and those with PROS. This study provides vital insights for healthcare professionals to navigate AEs in clinical practice and informs future research for enhancing alpelisib 's safety profile.

Managing hyperglycemia and rash associated with alpelisib: expert consensus recommendations using the Delphi technique

Hyperglycemia and rash are expected but challenging adverse events of phosphatidylinositol-3-kinase inhibition (such as with alpelisib). Two modified Delphi panels were conducted to provide consensus recommendations for managing hyperglycemia and rash in patients taking alpelisib. Experts rated the appropriateness of interventions on a 1-to-9 scale; median scores and dispersion were used to classify the levels of agreement. Per the hyperglycemia panel, it is appropriate to start alpelisib in patients with HbA1c 6.5% (diabetes) to <8%, or at highest risk for developing hyperglycemia, if they have a pre-treatment endocrinology consult. Recommend prophylactic metformin in patients with baseline HbA1c 5.7% to 6.4%. Metformin is the preferred first-line anti-hyperglycemic agent. Per the rash panel, initiate prophylactic nonsedating H1 antihistamines in patients starting alpelisib. Nonsedating H1 antihistamines and topical steroids are the preferred initial management for rash. In addition to clinical trial evidence, these recommendations will help address gaps encountered in clinical practice.

Predictive, preventive, and personalized medicine in breast cancer: targeting the PI3K pathway

Breast cancer (BC) is a multifaceted disease characterized by distinct molecular subtypes and varying responses to treatment. In BC, the phosphatidylinositol 3-kinase (PI3K) pathway has emerged as a crucial contributor to the development, advancement, and resistance to treatment. This review article explores the implications of the PI3K pathway in predictive, preventive, and personalized medicine for BC. It emphasizes the identification of predictive biomarkers, such as PIK3CA mutations, and the utility of molecular profiling in guiding treatment decisions. The review also discusses the potential of targeting the PI3K pathway for preventive strategies and the customization of therapy based on tumor stage, molecular subtypes, and genetic alterations. Overcoming resistance to PI3K inhibitors and exploring combination therapies are addressed as important considerations. While this field holds promise in improving patient outcomes, further research and clinical trials are needed to validate these approaches and translate them into clinical practice.

Jean DJ, Tieu T, Ladd B, Hilbert B, Wang W, Alltucker JT, Manimala S, Kryukov GV, Brooijmans N, Dowdell G, Jonsson P, Huff M, Guzman-Perez A, Jackson EL, Goncalves MD, Stuart DD. STX-478, a Mutant-Selective, Allosteric PI3Kα Inhibitor Spares Metabolic Dysfunction and Improves Therapeutic Response in PI3Kα-Mutant Xenografts

Phosphoinositide 3-kinase α (PIK3CA) is one of the most mutated genes across cancers, especially breast, gynecologic, and head and neck squamous cell carcinoma tumors. Mutations occur throughout the gene, but hotspot mutations in the helical and kinase domains predominate. The therapeutic benefit of isoform-selective PI3Kα inhibition was established with alpelisib, which displays equipotent activity against the wild-type and mutant enzyme. Inhibition of wild-type PI3Kα is associated with severe hyperglycemia and rash, which limits alpelisib use and suggests that selectively targeting mutant PI3Kα could reduce toxicity and improve efficacy. Here we describe STX-478, an allosteric PI3Kα inhibitor that selectively targets prevalent PI3Kα helical- and kinase-domain mutant tumors. STX-478 demonstrated robust efficacy in human tumor xenografts without causing the metabolic dysfunction observed with alpelisib. Combining STX-478 with fulvestrant and/or cyclin-dependent kinase 4/6 inhibitors was well tolerated and provided robust and durable tumor regression in ER+HER2- xenograft tumor models.

SIGNIFICANCE

These preclinical data demonstrate that the mutant-selective, allosteric PI3Kα inhibitor STX-478 provides robust efficacy while avoiding the metabolic dysfunction associated with the nonselective inhibitor alpelisib. Our results support the ongoing clinical evaluation of STX-478 in PI3Kα-mutated cancers, which is expected to expand the therapeutic window and mitigate counterregulatory insulin release. See related commentary by Kearney and Vasan, p. 2313. This article is featured in Selected Articles from This Issue, p. 2293.

Beyond Skin Rash: Alpelisib-Induced Anaphylactic Reactions

Alpelisib is a specific oral PI3K inhibitor used combined with fulvestrant for the treatment of patients with HR+/HER2-/PIK3CA-mutated metastatic breast cancer. Adverse drug reactions with alpelisib are common, including hyperglycemia and rash. Here we describe extraordinary and life-threatening reactions beyond skin rash in two patients with progressive PIK3CA-mutated metastatic cancer in whom alpelisib was initiated. Case-A (vaginal cancer): After 10 days on treatment, she developed dry eyes, generalized rash and itching. Alpelisib was interrupted and symptomatic treatment initiated. Because of an initial tumor response, a rechallenge was done. Ninety minutes after a reduced dose of alpelisib, she developed an anaphylactic reaction with angioedema, hypotension, and skin rash. Case-B (breast cancer): After 11 days on treatment, she developed skin rash and alpelisib was interrupted. At re-initiation, she felt tingles in her face and ears and some skin erythema. Given the mild rash, a second rechallenge with premedication was performed. Ninety minutes after a reduced dose of alpelisib, she developed a type-1 allergic reaction with angioedema, tingles, and skin rash. In both cases, a type-1 allergic reaction was diagnosed and symptomatic treatment was initiated, alpelisib was permanently discontinued and the patients fully recovered the next week(s). This report underlines the critical importance to consider type-I allergic reactions in the differential diagnosis in cases of rash associated with alpelisib. Even if a reaction develops after days on treatment, a type-I allergic reaction cannot be excluded. A rechallenge can be dangerous and should always be well contemplated or even avoided.

Alpelisib for the treatment of PIK3CA-related head and neck lymphatic malformations and overgrowth

PURPOSE

PIK3CA-related overgrowth spectrum (PROS) conditions of the head and neck are treatment challenges. Traditionally, these conditions require multiple invasive interventions, with incomplete malformation removal, disfigurement, and possible dysfunction. Use of the PI3K inhibitor alpelisib, previously shown to be effective in PROS, has not been reported in PIK3CA-associated head and neck lymphatic malformations (HNLMs) or facial infiltrating lipomatosis (FIL). We describe prospective treatment of 5 children with PIK3CA-associated HNLMs or head and neck FIL with alpelisib monotherapy.

METHODS

A total of 5 children with PIK3CA-associated HNLMs (n = 4) or FIL (n = 1) received alpelisib monotherapy (aged 2-12 years). Treatment response was determined by parental report, clinical evaluation, diary/questionnaire, and standardized clinical photography, measuring facial volume through 3-dimensional photos and magnetic resonance imaging.

RESULTS

All participants had reduction in the size of lesion, and all had improvement or resolution of malformation inflammation/pain/bleeding. Common invasive therapy was avoided (ie, tracheotomy). After 6 or more months of alpelisib therapy, facial volume was reduced (range 1%-20%) and magnetic resonance imaging anomaly volume (range 0%-23%) were reduced, and there was improvement in swallowing, upper airway patency, and speech clarity.

CONCLUSION

Individuals with head and neck PROS treated with alpelisib had decreased malformation size and locoregional overgrowth, improved function and symptoms, and fewer invasive procedures.

Real world outcomes with alpelisib in metastatic hormone receptor-positive breast cancer patients: A single institution experience

Background

It is critically important to study the real-world data of FDA-approved medications to understand the response rates and toxicities observed in the real-world population not represented in the clinical trials.

Methods

We reviewed charts of patients diagnosed with metastatic, hormone receptor-positive, human epidermal growth factor receptor 2 negative, PIK3CA-mutated breast cancer treated with alpelisib from May 2019 to January 2022. Clinical characteristics and treatment outcomes were collected. The association of clinical characteristics with responses and adverse events (AEs) was evaluated using the logistic regression model.

Results

27 patients were included. Median age at alpelisib initiation 67 years (range: 44, 77 years). Majority of patients had excellent performance status at time of alpelisib initiation. Most patients had chronic comorbidities, notably; 2 patients had controlled type 2 diabetes mellitus at time of alpelisib initiation. Majority had a median of three lines of therapy (range: 1, 7) before alpelisib. Clinical responses were determined using RECIST v1.1. 3/27 (11.11%) patients discontinued therapy before response assessment due to grade 3 AEs. Overall response rate was 12.5% (3/24), with all partial responses (PR). The median duration of response was 5.77 months (range: 5.54, 8.98). 14/27 (51.9%) of patients required dose interruption/reduction. Overall, 23/27 (85.19%) patients discontinued alpelisib of which 11 (47.83%) discontinued alpelisib due to AEs. Median duration of treatment was 2 months in patients who had grade 3 AEs (range: <1.00, 8.30) and 6.28 (1.15, 10.43) in those who did not. Any grade AEs were reported in 24/27 (88.9%) patients, namely, hyperglycemia 16/27 (59.3%), nausea 11/27 (40.7%), diarrhea 10/27 (37.0%), fatigue 7/27 (25.9%) and rash 6/27 (22.2%). Grade 3 AEs were reported in 13/27 patients (50%), namely, hyperglycemia in 7/27 (53.8%) patients followed by skin rash 4/27 (30.8%), GI side effects 3/27 (23.1%). Those with progressive disease as best response to alpelisib, had more non-metabolic comorbidities, higher number of liver metastases, PIK3CA E545K mutations, and shorter duration on therapy compared to those with PR and stable disease.

Conclusion

Patients should be counseled about the toxicity and modest benefit observed with alpelisib in real-world clinical practice when used in later lines of therapy.

Incidence of Cutaneous Adverse Events With Phosphoinositide 3-Kinase Inhibitors as Adjuvant Therapy in Patients With Cancer: A Systematic Review and Meta-analysis

Importance

The phosphoinositide 3-kinase (PI3K) pathway is among the most frequently activated pathways in human cancers. As the use of PI3K inhibitors for cancer treatment grows, there is increasing need for understanding the cutaneous effects associated with these therapies.

Objective

To systematically review the published literature reporting incidence of cutaneous adverse events with PI3K inhibitors and to provide pooled incidence estimates using meta-analysis.

Data Sources

This systematic review and meta-analysis was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guidelines. The literature search concerned entries through September 2021 in the following sources: PubMed, Cochrane registry, ClinicalTrials.gov, and evidence from the NHS UK and Trip medical database. To analyze PI3K inhibitors' cutaneous adverse events incidence, only randomized clinical trials (RCTs) were considered. The search strategy used the following keywords: (prevalence OR incidence OR epidemiology) and (phosphoinositide 3 kinase inhibitors OR PI3K inhibitors). No language restriction was applied. Analysis was conducted on July 1, 2022.

Study Selection

Studies included phase 2 and phase 3 RCTs that reported incidence of cutaneous adverse events associated with use of PI3K inhibitors.

Data Extraction and Measures

Data extracted included sex, medication name and class, sample size, rash incidence, and grade. The bias risk was assessed by the Cochrane tool for risk of bias assessment in RCTs.

Main Outcomes and Measures

The primary outcome was incidence of PI3K inhibitor cutaneous adverse events (with 95% CIs) among the overall population and among subgroups. Between-study heterogeneity was assessed using the I2 statistic.

Results

The analysis found the incidence of PI3K inhibitor cutaneous events of any grade to be 29.30% in the intervention group, translating to a pooled odds ratio (OR) for incidence of cutaneous adverse events of any grades of 2.55 (95% CI, 1.74-3.75). Incidence of severe grade (grade ≥3) of rash in the intervention group was estimated to be 6.95%, yielding a pooled Peto OR of 4.64 (95% CI, 2.70-7.97). Subgroup analyses revealed that the incidence of severe cutaneous adverse events (grade ≥3) was higher with the use of Pan-class-1 PI3K inhibitors (OR, 6.67; 95% CI, 4.28-10.38) than isoform-selective PI3K inhibitors (OR, 6.37; 95% CI, 3.25-12.48).

Conclusions and Relevance

This systematic review and meta-analysis identified an overall incidence of PI3K inhibitor cutaneous adverse events of any grade to be 29.30% with a pooled OR of 2.55; (95% CI, 1.74-3.75). These findings clarify the risk of cutaneous adverse events associated with this important class of anticancer therapies.

Risk of cutaneous adverse events in cancer patients treated with phosphatidylinositol-3-kinase inhibitors: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Cutaneous adverse effects (AEs) are common following the phosphoinositide-3-kinase (PI3K) inhibitors treatment. We aim to estimate the incidence and risk of PI3K inhibitor-related cutaneous AEs.

METHODS

The protocol was submitted to the PROSPERO registry. We searched ClinicalTrials.gov and international databases up to July 29, 2022. Meta-analysis was conducted by using risk ratios (RRs) with 95% confidence intervals (CIs).

RESULTS

Fourteen randomized controlled trials (RCTs) comprising 3877 patients were analyzed in this study. Compared with control arms, PI3K inhibitors showed a significant increase in the risk of all-grade rash, high-grade rash, and serious rash events (RR 2.29, 95% CI 1.58-3.31, p < 0.00001; RR 9.34, 95% CI 4.21-20.69, p < 0.00001; RR 5.11, 95% CI 2.11-12.36, p = 0.0003). The overall incidences of all-grade rash and high-grade rash were 26.2% (592/2257) and 4.4% (66/1487). Subgroup analyses of all-grade rash according to cancer types and PI3K inhibitor assignations identified the significant associations. PI3K inhibitors also significantly increased the risk of pruritus and dry skin (RR 1.63, 95% CI 1.14-2.33, p = 0.007; RR 3.34, 95% CI 2.30-4.85, p < 0.00001), with incidences of 13.4% (284/2115) and 9.8% (141/1436) in the treatment group.

CONCLUSION

There is a significantly increased risk of some cutaneous AEs in patients using PI3K inhibitors. Advance intervention is recommended in case of severe and life-threatening events. Further research is required to investigate the risk factors and pathogenesis.

Periorbital edema associated with alpelisib

Alpelisib is an alpha isoform-specific phosphatidylinositol 3-kinase (PI3K) inhibitor approved for use in the treatment of hormone receptor (HR)-positive, human epidermal growth factor receptor (HER2)-negative metastatic breast cancer in combination with fulvestrant. Hyperglycemia, rash, and gastrointestinal upset are the most commonly reported adverse events associated with alpelisib. Although rash is a known on-target effect of alpelisib, patients typically present with a morbilliform rash. We describe two cases of periorbital edema associated with alpelisib. We discuss the clinical findings, management, and prognosis of this unique reaction. These cases highlight the importance of early involvement of dermatology to manage adverse cutaneous events associated with alpelisib.

Characterization, management, and risk factors of hyperglycemia during PI3K or AKT inhibitor treatment

PURPOSE

The phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) pathway controls insulin sensitivity and glucose metabolism. Hyperglycemia is one of the most common on-target adverse effects (AEs) of PI3K/AKT inhibitors. As several PI3K and AKT inhibitors are approved by the United States Food and Drug Administration or are being studied in clinical trials, characterizing this AE and developing a management strategy is essential.

METHODS

Patients with hematologic or solid malignancies treated at Memorial Sloan Kettering Cancer Center with a PI3K or AKT inhibitor were included in this retrospective analysis. A search for patients experiencing hyperglycemia was performed. The frequency, management interventions and outcomes were characterized.

RESULTS

Four hundred and ninety-one patients with 10 unique cancer types who received a PI3K or AKT inhibitor were included. Twelve percent of patients required a dose interruption, 6% of patients required a dose reduction and 2% of patients were hospitalized to manage hyperglycemia. No events occurred among patients receiving β-, γ-, or δ- specific PI3K inhibitor. There was one case where the PI3K or AKT inhibitor was permanently discontinued due to hyperglycemia. Metformin was the most commonly used antidiabetic medication, followed by insulin, sodium-glucose transport protein 2 (SGLT2) inhibitors, and sulfonylurea. SGLT2 inhibitors were associated with the greatest reductions in blood sugar, followed by metformin. At least one case of euglycemic diabetic ketoacidosis (DKA) occurred in a patient on PI3K inhibitor and SGLT2 inhibitor. Body mass index ≥ 25 and HbA1c  ≥ 5.7 are were independently significant predictors of developing hyperglycemia.

CONCLUSION

Hyperglycemia is one of the major on-target side effects of PI3K and AKT inhibitors. It is manageable with antidiabetic medications, treatment interruption and/or dose modification. We summarize pharmacological interventions that may be considered for PI3K/AKT inhibitor induced hyperglycemia. SGLT2-inhibitor may be a particularly effective second-line option after metformin but there is a low risk of euglycemic DKA, which can be deadly. To our knowledge, our report is the largest study of hyperglycemia in patients receiving PI3K/AKT inhibitors.

A multidisciplinary approach to optimizing care of patients treated with alpelisib

PURPOSE

The oral, α-specific phosphatidylinositol-3-kinase (PI3Kα) inhibitor alpelisib is the first PI3K inhibitor approved for the treatment of advanced breast cancer. As alpelisib is a relatively new therapeutic option, specific guidance and a multidisciplinary approach are needed to provide optimal patient care. The primary objective of this manuscript is to provide comprehensive guidance on minimizing and managing adverse events (AEs) for patients with advanced breast cancer who are receiving alpelisib.

METHODS

Clinical studies, prescribing information, published literature, and relevant guidelines were reviewed to provide recommendations on the prevention and management of alpelisib-associated AEs.

RESULTS

The most common AEs associated with alpelisib in the phase 3 SOLAR-1 trial were hyperglycemia and rash (which are considered on-target effects of PI3Kα inhibition) and gastrointestinal AEs, including diarrhea, nausea, and decreased appetite. These AEs require regular monitoring, early recognition, and prompt initiation of appropriate treatment. In addition, there are effective strategies to reduce the onset and severity of frequently observed AEs-in particular, onset of hyperglycemia and rash may be reduced by lifestyle changes (such as reduced intake of carbohydrates and regular exercise) and antihistamine prophylaxis, respectively. To reduce risk of severe hyperglycemia, it is essential to achieve adequate glycemic control prior to initiation of alpelisib treatment.

CONCLUSION

Overall, alpelisib-associated AEs are generally manageable with prompt recognition, regular monitoring, and appropriate intervention, preferably with a multidisciplinary approach.

Factors leading to alpelisib discontinuation in patients with hormone receptor positive, human epidermal growth factor receptor-2 negative breast cancer

PURPOSE

Alpelisib is a phosphoinositide-3-kinase inhibitor approved for hormone-receptor-positive, PIK3CA-mutated metastatic breast cancer. However, length of drug exposure, maximum-tolerated dose, and therefore clinical response can vary significantly outside of the trial setting. This study evaluates our center's "real world" experience with alpelisib and focuses on duration of therapy and factors associated with cancer progression.

METHODS

Patients receiving alpelisib at our center between 2019 and 2021 were identified. We evaluated duration of alpelisib therapy and the causative reasons for drug discontinuation. The association of drug duration and dose with subsequent cancer progression were assessed, along with the association between hyperglycemia during alpelisib therapy and cancer progression.

RESULTS

Sixty-two women prescribed alpelisib were included (mean age 61 years). Disease progression was the most common reason for drug discontinuation, while discontinuation within 30 days was primarily attributed to adverse events (AEs). Among those who progressed, median time to progression was longer in those on alpelisib for > 90 days compared with those on alpelisib for ≤ 90 days (187 vs. 77 days, p < 0.001). At 200 days, freedom from progression was greater for those on alpelisib for > 90 days compared to those receiving therapy for ≤ 90 days (59% vs. 19%, p = 0.001). Median blood glucose as a continuous variable was associated with disease progression (HR 1.01, 95% CI 1.00-1.02, p = 0.02).

CONCLUSION

While progression of disease is the largest contributor to alpelisib discontinuation, AEs are the leading cause for early drug cessation. Shorter alpelisib exposure is associated with greater cancer progression. Further studies are needed to determine the impact of sustained hyperglycemia on cancer progression.

Diverse landscape of dermatologic toxicities from small-molecule inhibitor cancer therapy

BACKGROUND

Advances in molecular biology and genetics have contributed to breakthrough treatments directed at specific pathways associated with the development of cancer. Small-molecule inhibitors (Nibs) aimed at a variety of cellular pathways have been efficacious; however, they are associated with significant dermatologic toxicities.

METHODS

We conducted a comprehensive review of dermatologic toxicities associated with Nibs categorized into the following five groups: (a) mitogen-activated protein kinase; (b) growth factor/multi-tyrosine kinase; (c) cell division/DNA repair; (d) signaling associated with myeloproliferative neoplasms; and (e) other signaling pathways. Prospective phase I, II, or III clinical trials, retrospective literature reviews, systematic reviews/meta-analyses, and case reviews/reports were included for analysis.

RESULTS

Dermatologic toxicities reviewed were associated with every class of Nibs and ranged from mild to severe or life-threatening adverse skin reactions. Inflammatory reactions manifesting as maculopapular, papulopustular/acneiform, and eczematous lesions were frequent types of dermatologic toxicities seen with Nibs. Squamous cell carcinoma with keratoacanthoma-like features was associated with a subset of Nibs. Substantial overlap in dermatologic toxicities was found between Nibs.

CONCLUSIONS

Dermatologic toxicities from Nibs are diverse and may overlap between classes of Nibs. Recognition of the various types of toxicities from Nibs is critical for patient care in the era of "oncodermatology/dermatopathology."

Case Report: Alpelisib-Induced Drug Reaction With Eosinophilia and Systemic Symptoms: A Rare Manifestation of a Common Side Effect

Alpelisib is a PIK3a inhibitor approved for the treatment of metastatic ER+ breast cancer in combination with fulvestrant. Although rash is a common side effect of this medication, we present the first case of drug reaction with eosinophilia and systemic symptoms (DRESS) upon initial exposure to alpelisib. Here we describe the clinical-pathological findings and management of our patient with alpelisib-induced life-threatening DRESS syndrome. The goal of this case report is to highlight association of alpelisib with DRESS syndrome, in clinical practice, so that alpelisib can be immediately stopped and treatment for this serious condition promptly initiated.