Exact Sciences Presents Data Demonstrating Advancement in Blood-based Colorectal Cancer Screening at ESMO 2024

On September 16, 2024 Exact Sciences Corp. (NASDAQ: EXAS), a leading provider of cancer screening and diagnostic tests, reported performance data for its blood-based colorectal cancer (CRC) screening test (Press release, Exact Sciences, SEP 16, 2024, View Source [SID1234646634]). Results show sensitivities of 88.3% for CRC and 31.2% for advanced precancerous lesions at specificity of 90.1% for negative samples confirmed by colonoscopy. Results were presented today at the European Society for Medical Oncology (ESMO) (Free ESMO Whitepaper) Congress in an oral presentation titled, "Organ-specific performance of a multi-analyte, multi-cancer early detection (MCED) blood test in a prospectively-collected cohort."

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"The Exact Sciences team is constantly innovating to help close the screening gap," said Kevin Conroy, chairman and CEO, Exact Sciences. "The insights that led to this innovation reflect our understanding of the biology of cancer and the power of our scientific capabilities. We took a unique scientific approach to developing this test by combining a novel panel of markers. This led to data that improve upon what we previously thought was possible with a blood-based colorectal cancer screening test."

To optimize the final test algorithm, Exact Sciences designed a study to simulate the screening population in the United States and better predict real-world, prospective performance of a novel test. The study consisted of more than 3,000 blood samples, including approximately 2,900 blinded, prospectively collected samples from the pivotal BLUE-C study. This analysis was prespecified with the U.S. Food and Drug Administration (FDA) and the samples will be excluded from the final clinical validation. The study also included more than 90 advanced precancerous lesions, the majority of which were prospectively collected, and 60 case-collected colorectal cancer samples. In the pivotal BLUE-C study results, performance degradation is expected for advanced precancerous lesion sensitivity and overall CRC sensitivity.

Results of this study show the potential of a novel, highly discriminate blood-based panel of methylated DNA markers and an impactful, new marker class to detect advanced precancerous lesions and cancers at an attractive cost profile. The company will implement the innovative marker class on a new testing platform and complete additional analytical studies to support an FDA submission.

"A blood-based colorectal cancer screening test that can detect advanced precancerous lesions at a level comparable to the FIT test would be a breakthrough in this field," said Paul Limburg, MD, MPH, AGAF, chief medical officer for Screening, Exact Sciences. "Results from this large, well-designed study show progress toward that goal and move us one step closer toward providing average-risk patients with another non-invasive screening option."

BLUE-C results for Exact Sciences’ blood-based CRC screening test are now expected in the first half of 2025. Exact Sciences plans to use these results to support an FDA submission and approval and to make the blood-based CRC screening test available broadly. If approved, the blood-based CRC screening test could provide another testing option for 60 million unscreened people1 in the United States. It would be supported by Exact Sciences’ commercial infrastructure and ExactNexus technology platform, making electronic ordering and resulting seamless for more than 350 health systems.

The company also presented data from its multi-cancer early detection (MCED) blood test, assessing organ-specific performance of methylation and protein biomarkers in a prospectively collected cohort of samples from its ASCEND 2 study. The analysis indicated an overall sensitivity of 54.8% with 98.5% specificity in cancers without standard-of-care screening options (excluding lung) and 63.7% in the six most aggressive cancers with the shortest survival rates (esophagus, liver, lung, ovarian, pancreatic, and stomach). These findings highlight the potential clinical value of using multiple biomarkers to detect various cancer types, including the most aggressive and those without recommended screening options.

TME Pharma Announces Oral Presentation at ESMO Congress 2024 With Updated Results From NOX-A12 GLORIA Phase 1/2 Trial in Glioblastoma

On September 16, 2024 TME Pharma N.V., a clinical-stage biotechnology company focused on developing novel therapies for treatment of cancer by targeting the tumor microenvironment (TME), reported an oral presentation by Dr. Frank A. Giordano, lead investigator of the NOX-A12 GLORIA Phase 1/2 trial in first-line brain cancer (glioblastoma), taking place on Sunday, September 15, 2024, at the European Society for Medical Oncology (ESMO) (Free ESMO Whitepaper) Congress in Barcelona, Spain (Press release, TME Pharma, SEP 16, 2024, View Source [SID1234646633]). The presentation provided the updated results and key conclusions from the combined therapy with NOX-A12 and bevacizumab in newly diagnosed glioblastoma patients resistant to standard chemotherapy (MGMT unmethylated) with residual detectable tumor after surgery.

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In the presentation, Dr. Giordano highlighted that inhibition of two paths of brain tumor revascularization after radiation – vasculogenesis with NOX-A12 and angiogenesis with bevacizumab – resulted in deeper clinical responses, i.e. stronger shrinkage of tumor size compared to NOX-A12 therapy alone. The research showed a significant decrease in tumor perfusion which supports the suggested mode of action of the combination therapy. The presentation also reveals that the deeper responses to the combination therapy with NOX-A12 and bevacizumab translate to significantly longer median progression free survival (mPFS: 9.1 months, p=0.003) and median overall survival (mOS: 19.9 months, p=0.005) compared to a matched SOC reference cohort (mPFS: 4.0 months; mOS: 9.5 months) or to NOX-A12 alone (mPFS: 5.7 months; mOS: 12.7 months). Two out of the six glioblastoma patients in the NOX-A12 + bevacizumab arm of the GLORIA trial survived for more than 26 months since the start of therapy.

"The median OS of 19.9 months achieved in patients receiving combination therapy in the GLORIA study is especially exciting when considering the prognosis this chemotherapy-refractory patient population with residual detectable tumor after surgery would otherwise face on current standard of care, notably survival of approximately 10 months," said Aram Mangasarian, CEO of TME Pharma. "What further strengthens our confidence in our dual inhibition approach is the tumor tissue analysis showing spatially distinct expression patterns of NOX-A12’s target CXCL12 and VEGF. This indicates that the two different ways of growing blood vessels occur in different tumor structures: vasculogenesis driven by NOX-A12’s target, and angiogenesis driven by bevacizumab’s target. This helps explain why combined inhibition of both pathways is needed to effectively prevent tumor vasculature restoration after radiotherapy."

Details of the oral presentation at the ESMO (Free ESMO Whitepaper) Congress 2024 are as follows:

Title: Dual inhibition of postradiogenic angio-vasculogenesis in glioblastoma: Results of the phase 1/2 GLORIA trial
Presenter: Dr. Frank A. Giordano, Chair of the Department of Radiation Oncology, University Medical Center Mannheim, Germany
Session: Mini oral session: CNS tumors
Time and Date: 08.30-8.35 a.m. CEST, Sunday, September 15, 2024

Neoadjuvant TAR-200 plus cetrelimab nearly doubles the pathological complete response rate compared to cetrelimab alone in patients with muscle-invasive bladder cancer

On September 16, 2024 Johnson & Johnson (NYSE: JNJ) reported interim data from the ongoing Phase 2 SunRISe-4 study showing neoadjuvant treatment with investigational TAR-200 plus cetrelimab (CET) achieved nearly double the pathological complete response (pCR) rate compared to CET alone in patients with muscle-invasive bladder cancer (MIBC) who are ineligible or refuse neoadjuvant platinum-based chemotherapy and scheduled for radical cystectomy (RC) (Press release, Johnson & Johnson, SEP 16, 2024, View Source [SID1234646627]). These data were featured as a late-breaking oral presentation at the European Society of Medical Oncology (ESMO) (Free ESMO Whitepaper) 2024 Congress (Abstract #LBA84).

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"These findings from the SunRISe-4 study show for the first time that an intravesical treatment with TAR-200, combined with a systemic PD-1 inhibitor, could potentially result in a complete pathological response in a high proportion of patients, as well as allowing a tolerable approach," said Andrea Necchi, M.D., of Italy’s Vita-Salute San Raffaele University and the IRCCS San Raffaele Hospital and Scientific Institute and a presenting author of the study. "These preliminary findings show a potential for a future change in the local treatment of muscle-invasive bladder carcinoma using TAR-200."

In the interim analysis of the SunRISe-4 study, neoadjuvant TAR-200 plus CET (n=53) showed overall efficacy with a centrally confirmed pathologic complete response (pCR, [T0]) rate of 42 percent compared to 23 percent (95 percent CI, 28-56; 10-41, respectively) with CET alone (n=31) in patients with histologically proven, non-metastatic MIBC. The pathological overall response (pOR) rate (defined as the proportion of patients ≤ pT1) was 60 percent compared to 36 percent, respectively (CI 95 percent, 46-74; 19-55).1

In a subgroup analysis of patients with organ-confined disease (cT2), those treated with TAR-200 plus CET (n=40) showed a 48 percent pCR rate compared to 23 percent pCR with CET alone (n=26, 95 percent CI, 32-64; 9-44, respectively) and 68 percent were downstaged (≤ pT1) at the time of radical cystectomy, potentially improving surgical outcomes and reducing risk of recurrence.1

"With these promising results, TAR-200 plus cetrelimab as a neoadjuvant therapy before radical cystectomy could potentially alter how bladder cancer is treated," said Kiran Patel, M.D., Vice President, Clinical Development, Solid Tumors, Innovative Medicine, Johnson & Johnson. "This investigational innovative approach may offer a possible alternative for many patients who are not eligible for the current standard of pre-operative treatments."

Treatment-related adverse events (TRAEs) occurred in 72 percent of patients treated with TAR-200 combined with CET and 44 percent of patients treated with CET alone, with the majority being Grade 1-2. Nine percent of patients discontinued treatment with TAR-200 and eight percent discontinued treatment with CET in the combined treatment cohort due to TRAEs; no patients discontinued treatment due to TRAEs when treated with CET alone.1

Bladder cancer is the ninth most common cancer in the world.2 Although BCG immunotherapy has been accepted as the standard of care for nearly five decades, 30-40 percent of patients do not respond to BCG and experience disease recurrence or progression.3 In such scenarios, radical cystectomy (removal of the bladder and neighboring structures and organs) emerges as the primary treatment option. This major abdominal procedure requires a urinary diversion to be created to collect and store urine.4

TAR-200 is an investigational targeted releasing system designed to provide extended local release of gemcitabine into the bladder. It is installed in a physician’s office setting during a 2-3 minute procedure with no anesthesia. In December 2023, the FDA granted TAR-200 Breakthrough Therapy Designation (BTD) for the potential future treatment of patients with BCG-unresponsive HR-NMIBC, who are ineligible for or elected not to undergo radical cystectomy (surgical removal of the bladder).

About SunRISe-4
SunRISe-4 (NCT04919512) is an open-label, multicenter, randomized Phase 2 study assessing the efficacy and safety of neoadjuvant TAR-200 + cetrelimab (CET) (anti-programmed death-1 antibody) or neoadjuvant CET alone in patients with MIBC scheduled for RC who are ineligible for or refuse neoadjuvant platinum-based chemotherapy.

About TAR-200
TAR-200 is an investigational targeted releasing system, enabling extended release of gemcitabine into the bladder, increasing the amount of time the drug delivery system spends in the bladder and sustaining local drug exposure. The safety and efficacy of TAR-200 are being evaluated in Phase 2 and Phase 3 studies in patients with MIBC in SunRISe-2 and SunRISe-4, and NMIBC in SunRISe-1, SunRISe-3 and SunRISe-5.

About Cetrelimab
Cetrelimab is an investigational programmed cell death receptor-1 (PD-1) monoclonal antibody being studied for the treatment of bladder cancer, prostate cancer, melanoma, and multiple myeloma as part of a combination treatment. Cetrelimab is also being evaluated in multiple other combination regimens.

About Muscle-Invasive Bladder Cancer
Muscle-invasive bladder cancer (MIBC) is a severe form of bladder cancer where the tumor penetrates the muscular layer of the bladder wall, significantly increasing the risk of metastasis.5 Approximately 25 percent of bladder cancer cases are diagnosed as MIBC at the time of initial presentation.6 Early detection and timely intervention are crucial for managing MIBC, as delayed treatment can lead to poor prognosis.

Immutep’s Efti in Combination with MSD’s KEYTRUDA® Leads to Positive Efficacy with Favourable Safety in First Line Head and Neck Cancer

On September 16, 2024 Immutep Limited, a clinical-stage biotechnology company developing novel LAG-3 immunotherapiesfor cancer and autoimmune disease, reported positive efficacy and safety results from the TACTI-003 Phase IIb trial evaluating eftilagimod alpha (efti) in combination with MSD’s (Merck & Co., Inc., Rahway, NJ, USA) antiPD-1 therapy KEYTRUDA (pembrolizumab) as first-line treatment of recurrent or metastatic head and neck squamous cell carcinoma patients (1L HNSCC) (Press release, Immutep, SEP 16, 2024, View Source [SID1234646626]).

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These results with a data cut-off of 11 March 2024 were selected as a Proffered Paper oral presentation at the European Society for Medical Oncology (ESMO) (Free ESMO Whitepaper) Congress 2024 and were presented by Claus Kristensen, M.D., Ph.D., Head of Section for Thoracic and Head and Neck Oncology, Rigshospitalet, Copenhagen, Denmark, on 15 September. The data adds to the previously reported overall response rates and safety data on 27 June and 12 July.

Dr. Kristensen stated, "The efficacy and safety data in TACTI-003 are very encouraging and show the significant potential of this novel immunotherapy combination to fight difficult-to-treat head and neck squamous cell carcinomas. The clinically meaningful improvement in responses for patients with high PD-L1 expression in the randomised portion of the trial, combined with the compelling response rates in patients with no PD-L1 expression, are a testament to the complementary nature of efti in combination with KEYTRUDA. I am particularly impressed that these higher response rates and clear increase in biological activity seen in the efti arm do not come at the expense of durability of response or lead to an increased toxicity profile, which is often the case when combining therapies in the search for more efficacious treatments for cancer patients."

Dr. Frédéric Triebel, CSO of Immutep, said "Through multiple clinical trials, we see the promise of efti to not only improve cancer patients’ clinical responses to immune checkpoint inhibitors, but also to expand patient populations who respond to them including patients with negative PD-L1 expression. Once again, the TACTI003 trial has reinforced efti’s positive impact on both these fronts. We are excited to see efti in combination with KEYTRUDA now driving a 1.9-fold increase in responses for head and neck cancer patients with high PDL1 expression as compared to KEYTRUDA alone, and a statistically significant increase in absolute lymphocyte count in the treatment arm showing efti’s biological activity in a randomised setting."

Marc Voigt, CEO of Immutep, added "As we move into the latter half of 2024, we will continue to follow the data in TACTI-003 and start to engage with regulatory authorities regarding potential paths forward. We are certainly pleased with durability we are seeing, which is consistent with other trials in which efti combined with KEYTRUDA achieves a high DOR, unlike many other therapeutic combinations. We are hopeful this positive duration of response continues and, as seen in first line non-small cell lung cancer in the TACTI-002 trial evaluating efti in combination with KEYTRUDA, eventually contributes to an overall survival benefit for patients with first line head and neck cancer."

ESMO Congress 2024 Proffered Paper Oral Presentation
Title: Primary Results from TACTI-003: A Randomized Phase IIb Trial Comparing Eftilagimod Alpha (soluble LAG-3) Plus Pembrolizumab Versus Pembrolizumab Alone in First-Line Recurrent or Metastatic Head and Neck Squamous Cell Carcinoma with CPS ≥1

Clinical Highlights from Randomised Cohort A in 1L HNSCC Patients with Any PD-L1 Expression (CPS ≥1)
Efti leads to higher Objective Response Rates (ORR)
• Efti in combination with pembrolizumab (E+P) led to a 32.8% ORR (34.5% including one partial response reported after data cut-off) in evaluable patients with CPS ≥1 (N=58) compared to 26.7% for pembrolizumab in evaluable patients with CPS ≥1 (N=60), according to RECIST 1.1. Imbalances of prognostic markers towards the pembrolizumab alone arm included HPV status, smoking status, and primary tumour location.

• E+P outperformance in patients with any PD-L1 expression was strongest in high PD-L1 expressing patients (CPS ≥20) with a 31.0% ORR (N=29) versus an 18.5% ORR for pembrolizumab alone (N=27), along with a complete response rate of 6.9% in E+P arm versus 3.7% for pembrolizumab alone. An additional partial response was reported in CPS ≥20 after data cut-off leading to a 34.5% ORR, a 1.9- fold increase in responses over pembrolizumab alone in this patient group.

Efti maintains a high Duration of Response (DOR)
• Durability of response was achieved with the addition of efti with a median DOR of 17.5 months s in the E+P arm (N=58) as compared to 17.1 months in the pembrolizumab alone arm (N=60)
o Data compares favourably to other anti-PD-1 combinations with cytotoxic drugs like chemotherapy or EGFR inhibitors, including a historical DOR of ~6 to ~7 months from antiPD-1 combined with chemotherapy in 1L HNSCC1-4

Efti increases Biological Activity
• A statistically significant increase in absolute lymphocyte count (ALC), measured as an exploratory biomarker, was seen in the E+P arm as shown in the graphic below, indicating an effective eftiinduced immune response in this randomised setting
ALC increase is in line with data from other Phase II trials evaluating efti in combination with chemotherapy in metastatic breast cancer or pembrolizumab in non-small cell lung cancer5-6

Efti continues to have favourable safety profile
• Efti in combination with pembrolizumab continues to have a favourable safety profile with no new safety signals observed
o Discontinuation rate from treatment emergent adverse events was similar for both E+P (4.3%) and for pembrolizumab alone (4.4%)
o Unlike other combinations with anti-PD-1 therapy, E+P continues to have a comparable safety profile to pembrolizumab alone other than injection site reactions as expected with efti’s subcutaneous delivery.

Additionally, E+P drives a high ORR and Disease Control Rate (DCR) in 1L HNSCC patients regardless of PD-L1 expression. In Cohorts A and B together (N=89), E+P achieved a 33.7% ORR (34.8% including one partial response reported after data cut-off) including 31 patients in Cohort B with negative PD-L1 (CPS <1). E+P also achieved a higher DCR compared to pembrolizumab monotherapy across all PD-L1 expression levels, with a consistent increase from 58.1% DCR in CPS <1, to 69.0% DCR in CPS 1-19, to 75.9% DCR in CPS ≥20.

This new data adds to the body of evidence that efti’s activation of antigen-presenting cells provides a strong boost to the immune system, enhancing the potential of immune checkpoint inhibitors (ICI) such as KEYTRUDA. As the only MHC Class II agonist in clinical development today, efti generates a broad anti-cancer immune response in combination with ICIs regardless of PD-L1 expression, including for patients with negative PD-L1 expression, in a unique and safe manner across multiple different cancers.

Scorpion Therapeutics Presents Initial Clinical Data From Its Phase 1/2 Trial of STX-478 Demonstrating Potentially Best-in-Class Mutant-Selective PI3Kα Inhibition for the Treatment of Advanced Solid Tumors at ESMO Congress 2024

On September 15, 2024 Scorpion Therapeutics, Inc. ("Scorpion"), a pioneering clinical-stage oncology company dedicated to transforming the lives of cancer patients by redefining the frontier of precision oncology, reported initial, first-in-human clinical results from its Phase 1/2 study of STX-478 in advanced solid tumor patients in a Proffered Paper late-breaking session at the European Society for Medical Oncology ("ESMO") Congress 2024 in Barcelona, Spain (Press release, Scorpion Therapeutics, SEP 15, 2024, View Source [SID1234646635]). Initial Phase 1 monotherapy data for STX-478, an oral, once-daily, mutant-selective, allosteric PI3Kα inhibitor, demonstrated potentially best-in-class PI3Kα inhibition, with anti-tumor activity observed in multiple cancer types, including HR+/HER2- breast cancer (BC), gynecological tumors, and other solid tumors. STX-478 was well-tolerated, including in pre-diabetic, diabetic and heavily pre-treated patients and showed no significant wild-type-mediated toxicities.

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"Approved and investigational non-selective PI3Kα inhibitors, as well as approved AKT inhibitors, have shown clinical benefit in HR+/HER2- breast cancer in Phase 3 studies. However, their therapeutic benefit is limited by PI3Kα pathway inhibition in normal tissues, resulting in dose-limiting toxicities, including hyperglycemia, rash and diarrhea"

"We are pleased to report the initial Phase 1/2 trial results of STX-478, which was designed as the first PI3Kα inhibitor to fully maximize the potential of pathway inhibition in patients with solid tumors and is the first program emerging from our next-generation precision oncology discovery engine," said Adam Friedman, M.D., Ph.D., Chief Executive Officer of Scorpion. "STX-478 demonstrates potent and potentially best-in-class PI3Kα pathway inhibition as established by our early, differentiated signals of monotherapy efficacy, which exceed benchmarks of other pathway inhibitors. We also are encouraged by early safety data that demonstrates minimal evidence of wild-type PI3Kα-mediated toxicities, with no patients discontinuing STX-478 due to treatment-related adverse events. Together, these results suggest that our highly-selective mutant PI3Kα inhibitor could overcome the limitations of currently available pathway inhibitors and, consequently, meaningfully improve clinical outcomes for patients with PI3Kα kinase or helical domain-mutated solid tumors. We look forward to continuing to progress our clinical-stage and discovery pipeline as we work to broaden the reach and impact of precision oncology for patients with high unmet medical need."

"Approved and investigational non-selective PI3Kα inhibitors, as well as approved AKT inhibitors, have shown clinical benefit in HR+/HER2- breast cancer in Phase 3 studies. However, their therapeutic benefit is limited by PI3Kα pathway inhibition in normal tissues, resulting in dose-limiting toxicities, including hyperglycemia, rash and diarrhea," said Alberto J. Montero, M.D., affiliated with University Hospitals Cleveland, and trial investigator. "By selectively targeting mutant PI3Kα, one of the most prevalent oncogenes in cancer, STX-478 has the potential to improve clinical outcomes and quality of life for patients during treatment. In the trial, STX-478 achieves exposures capable of driving several-fold deeper target inhibition than other PI3Kα inhibitors, while avoiding their toxicities, even with the majority of patients having prediabetes or diabetes. I am excited about the early results in patients with breast cancer and other solid tumors and look forward to further clinical development."

Initial Data from the Phase 1/2 Study of STX-478 in Advanced Solid Tumors

In the Proffered Paper presented at ESMO (Free ESMO Whitepaper), 61 patients with both kinase and helical domain PIK3CA mutations were treated with STX-478 at doses ranging from 20mg to 160mg daily, as of the data cutoff on June 21, 2024. Of the enrolled patients, 29 patients had HR+/HER2- BC and 32 patients had other solid tumors. Additionally, 54% of patients were pre-diabetic or diabetic, and 41% of BC patients had a prior PI3Kα pathway inhibitor. 97% of BC patients had previously received a CDK4/6 inhibitor. Enrolled patients were heavily pre-treated with a median of three prior lines of therapy (ranging from 1-7).

Pharmacokinetic and Selectivity Profile

Preliminary pharmacokinetic analysis supports once-daily dosing of STX-478, with dose proportional and linear STX-478 plasma exposure and an estimated half-life of approximately 60 hours. At doses ≥ 40mg QD, STX-478 exceeded the average exposures needed for in vivo efficacy in mouse models and achieved target coverage several fold higher than other approved or investigational PI3Kα inhibitors. STX-478 reached a maximum tolerated dose (MTD) of 100mg daily.

Preliminary Safety Data

STX-478 was well-tolerated in a high-risk population, which included diabetics, pre-diabetics and patients intolerant to other PI3Kα pathway inhibitors, populations excluded from other PI3Kα studies. Most treatment-related adverse events (TRAEs) were mild-to-moderate and transient; TRAEs of ≥ 15% included: fatigue (30%), hyperglycemia (23%), nausea (20%) and diarrhea (15%). No Grade ≥ 3 PI3Kα WT toxicity adverse events (hyperglycemia, diarrhea and rash) were observed, and minimal changes in fasting glucose were observed at any STX-478 dose level.

No patients discontinued STX-478 due to a TRAE, and two dose-limiting toxicities observed at 160mg rapidly resolved after a brief dose interruption.

Initial Clinical Activity Data

As of the data cutoff in 43 evaluable patients, the confirmed/unconfirmed overall response rate (ORR) was 23% (5/22) in HR+/HER2- metastatic breast cancer; 21% (9/43) in all tumor types; and 44% (4/9) in gynecologic cancers, which compares favorably to approved PI3Kα pathway inhibitors (monotherapy ORR 4 – 6%). All responses were confirmed following the data cutoff. The disease control rate across tumors was 67%. Tumor reductions were seen in 72% of all patients as a monotherapy agent across all dose levels. Multiple responses were seen in both PI3Kα kinase and helical domain mutant tumors at multiple dose levels, and many responses were sustained and deepened over several months of therapy.

Mutant PIK3CA circulating tumor DNA levels markedly decreased on therapy in 86% of patients (19/22 evaluable patients).

The presentation will be available here on Scorpion’s website following the conclusion of the session.

"Scorpion is dedicated to bringing highly-selective small molecules to cancer patients as quickly as possible, and the presentation of these data is a testament to the team’s exceptional execution and the productivity of our fully-integrated discovery organization," said Mark Chao, M.D., Ph.D., Chief Medical Officer of Scorpion. "These exciting data bolster our confidence in the profile of STX-478 and in the continued advancement of the trial as we actively enroll patients into ongoing multiple expansion cohorts across a range of solid tumors and in combinations with active standard of care agents including fulvestrant and CDK4/6 inhibitors in HR+/HER2- breast cancer and lay the groundwork for the rapid advancement of this novel treatment. We would like to thank the patients, caregivers and investigators for sharing our commitment to advancing next-generation cancer treatments, and we look forward to providing updates from this study at future medical meetings."

About STX-478

STX-478 was designed to improve outcomes in patients harboring PI3Kα mutations, one of the most prevalent drivers of cancer, occurring in over 166,000 patients per year with breast, gynecological and other solid tumors in the United States alone. In preclinical models, STX-478 demonstrated robust activity across a range of both kinase and helical domain PI3Kα mutations while sparing wild-type PI3Kα activity in normal tissues; previous generations of non-selective PI3Kα inhibitors have limited patient benefit due to these on-target toxicities. Scorpion’s Phase 1/2 clinical trial is a multi-center, global, open-label study designed to evaluate the safety and tolerability of STX-478 in multiple ascending doses for patients with locally advanced or metastatic HR+/HER2- breast cancer and other solid tumors driven by PI3Kα mutations. The program has rapidly advanced into multiple expansion cohorts across a range of solid tumors and in breast cancer as monotherapy and in combinations with fulvestrant and CDK4/6 inhibitors. To learn more about the first-in-human trial of STX-478, please visit this page.