First-in-Human Study of STX-478 as Monotherapy and in Combination With Other Antineoplastic Agents in Participants With Advanced Solid Tumors
NCT ID: NCT05768139
Last Updated: 2025-12-24
Study Results
The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.
Basic Information
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RECRUITING
PHASE1/PHASE2
720 participants
INTERVENTIONAL
2023-04-17
2030-07-31
Brief Summary
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Part 1 will evaluate STX-478 as monotherapy in participants with advanced solid tumors. Part 2 will evaluate STX-478 therapy as combination therapy with fulvestrant in participants with hormone receptor positive (HR+) breast cancer. Part 3 will evaluate STX-478 as combination therapy with endocrine therapy (aromatase inhibitors, fulvestrant or imlunestrant) and a CDK4/6 Inhibitor (either Ribociclib, Palbociclib or Abemaciclib) in participants with HR+ breast cancer.
Each study part will include a 28-day screening period, followed by treatment with STX-478 monotherapy or combination therapy.
Detailed Description
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Conditions
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Keywords
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Study Design
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NON_RANDOMIZED
SEQUENTIAL
TREATMENT
NONE
Study Groups
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Dose Escalation (Advanced Solid Tumors)
* Cohort A0: Advanced Solid tumors expressing PI3Kα mutations
* Cohort A1: HR+ breast cancer expressing PI3Kα mutations
STX-478
STX-478 is a mutant-selective PI3Kα inhibitor
Dose Expansion
* Cohort A1: HR+/HER2- breast cancer expressing PI3Ka mutations
* Cohort A2: Gynecologic cancers
* Cohort A3: Head and Neck Squamous Cell Carcinoma
* Cohorts A4/A5: Other solid tumors not included in Cohorts A1, A2, or A3 expressing PI3Kα mutations
* Cohort A6: Endometrial cancer
STX-478
STX-478 is a mutant-selective PI3Kα inhibitor
Dose Selection/Expansion: Combination STX-478 + fulvestrant
Cohort B: HR+/HER2- or HR+/HER2low breast cancer expressing PI3Kα mutations
STX-478
STX-478 is a mutant-selective PI3Kα inhibitor
Fulvestrant
Fulvestrant
Dose Selection/Expansion Combination
STX-478 + Endocrine therapy + CDK4/6 inhibitor Cohort C/D/E: HR+/HER2- or HR+/HER2low breast cancer expressing PI3Ka mutations
STX-478
STX-478 is a mutant-selective PI3Kα inhibitor
Fulvestrant
Fulvestrant
Ribociclib
Ribociclib
Palbociclib
Palbociclib
Letrozole
Letrozole
Anastrozole
Anastrozole
Exemestane
Exemestane
Interventions
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STX-478
STX-478 is a mutant-selective PI3Kα inhibitor
Fulvestrant
Fulvestrant
Ribociclib
Ribociclib
Palbociclib
Palbociclib
Letrozole
Letrozole
Anastrozole
Anastrozole
Exemestane
Exemestane
Other Intervention Names
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Eligibility Criteria
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Inclusion Criteria
* Has a new or recent tumor biopsy (collected at screening, if feasible) or will provide an adequate tissue sample prior to screening
* Has a tumor that harbors a documented PI3Kα mutation (cohort specific criterion for cohort-specific mutation types)
* Is ≥18 years of age at the time of signing the ICF
* Has an ECOG performance status score of 0 or 1 at screening
* Has adequate organ function as defined per protocol
Exclusion Criteria
* Has symptomatic brain or spinal metastases
* Has an established diagnosis of uncontrolled diabetes mellitus (defined as HbA1c ≥8% and/or FBG ≥140 mg/dL \[7.7 mmol/L\] and/or requiring or required insulin).
* Has had prior treatment with PI3K/AKT/mTOR inhibitor(s), except in certain circumstances
* Has had treatment with any local or systemic antineoplastic therapy or investigational anticancer agent within 14 days or 4 half-lives, whichever is longer, prior to the initiation of study treatment up to a maximum washout period of 28 days. Endocrine therapy does not require a washout period if the patient is enrolling in a cohort with the same combination endocrine therapy.
* Has toxicities from previous anticancer therapies that have not resolved to baseline levels or CTCAE grade ≤1, with the exception of alopecia and peripheral neuropathy.
* Has had radiotherapy within 14 days before the initiation of study treatment
18 Years
ALL
No
Sponsors
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Eli Lilly and Company
INDUSTRY
Responsible Party
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Principal Investigators
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Call 1-877-CTLILLY (1-877-285-4559) or 1-317-615-4559 Mon - Fri 8 AM - 8 PM Eastern time (UTC/GMT - 5 hours, EST)
Role: STUDY_DIRECTOR
Eli Lilly and Company
Locations
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Ellison Clinic at Saint John's
Los Angeles, California, United States
UCSF Medical Center at Mission Bay
San Francisco, California, United States
University of Colorado Cancer Center
Aurora, Colorado, United States
Yale-New Haven Hospital
New Haven, Connecticut, United States
Florida Cancer Specialists ORLANDO/DDU
Lake Mary, Florida, United States
Moffitt Cancer Center
Tampa, Florida, United States
Winship Cancer Institute, Emory University
Atlanta, Georgia, United States
University of Iowa
Iowa City, Iowa, United States
Louisiana State University Health Sciences Center
New Orleans, Louisiana, United States
Massachusetts General Hospital
Boston, Massachusetts, United States
Dana-Farber Cancer Institute
Boston, Massachusetts, United States
Barbara Ann Karmanos Cancer Institute
Detroit, Michigan, United States
START Midwest
Grand Rapids, Michigan, United States
Saint Luke's Cancer Institute
Kansas City, Missouri, United States
Washington University
St Louis, Missouri, United States
Memorial Sloan Kettering Cancer Center
New York, New York, United States
UH Cleveland Medical Center
Cleveland, Ohio, United States
Stefanie Spielman Comprehensive Breast Center
Columbus, Ohio, United States
University of Oklahoma Health Sciences Center
Oklahoma City, Oklahoma, United States
Providence Cancer Institute Franz Clinic
Portland, Oregon, United States
The West Clinic, PLLC dba West Cancer Center
Germantown, Tennessee, United States
Sarah Cannon Research Institute
Nashville, Tennessee, United States
Mary Crowley Cancer Research Center
Dallas, Texas, United States
Texas Oncology-Baylor Charles A. Sammons Cancer Center
Dallas, Texas, United States
University of Texas Southwestern
Dallas, Texas, United States
University of Texas MD Anderson Cancer Center
Houston, Texas, United States
START San Antonio
San Antonio, Texas, United States
START Mountain Region
West Valley City, Utah, United States
University of Vermont Medical Center
Burlington, Vermont, United States
USO-Virginia Cancer Specialists, PC
Fairfax, Virginia, United States
Institut Jules Bordet
Anderlecht, , Belgium
UZ Leuven
Leuven, , Belgium
Institut Bergonié - Centre Régional de Lutte Contre Le Cancer de Bordeaux et Sud Ouest
Bordeaux, , France
Centre Leon Berard
Lyon, , France
Institut Paoli-Calmettes
Marseille, , France
Centre Antoine-Lacassagne
Nice, , France
Institut Claudius Regaud
Toulouse, , France
Gustave Roussy
Villejuif, , France
Universitätsklinikum Erlangen
Erlangen, , Germany
Universitätsmedizin Mannheim
Mannheim, , Germany
Mater Misericordiae Hospital
Dublin, , Ireland
Azienda Ospedaliera Nazionale Santi Antonio e Biagio e Cesare Arrigo
Alessandria, , Italy
Spedali Civili di Brescia
Brescia, , Italy
Istituto Nazionale per lo Studio e la Cura dei Tumori
Milan, , Italy
Istituto Europeo di Oncologia
Milan, , Italy
Fondazione IRCCS San Gerardo dei Tintori
Monza, , Italy
Ospedale Santa Maria delle Croci
Ravenna, , Italy
Fondazione Policlinico Universitario Agostino Gemelli
Roma, , Italy
Centro Ricerche Cliniche di Verona s.r.l.
Verona, , Italy
National Hospital Organization Kyushu Cancer Center
Fukuoka, , Japan
Kansai Medical University Hospital
Hirakata, , Japan
The Cancer Institute Hospital of JFCR
Kōtō City, , Japan
Kyoto University Hospital
Kyoto, , Japan
Netherlands Cancer Institute
Amsterdam, , Netherlands
Erasmus MC
Rotterdam, , Netherlands
Hospital Quiron Barcelona
Barcelona, , Spain
South Texas Accelerated Research Therapeutics (START) Barcelona- HM Nou Delfos
Barcelona, , Spain
Instituto Oncologico Dr Rosell (IOR)
Barcelona, , Spain
Hospital Universitari Vall d'Hebron
Barcelona, , Spain
Hospital San Pedro
Logroño, , Spain
MD Anderson Cancer Center
Madrid, , Spain
Hospital Clinico San Carlos
Madrid, , Spain
Hospital Universitario Fundación Jiménez Díaz
Madrid, , Spain
Hospital Universitario HM Sanchinarro
Madrid, , Spain
Hospital Universitario Quironsalud Madrid
Pozuelo de Alarcón, , Spain
Hospital Universitari Sant Joan de Reus
Reus, , Spain
Hospital Universitario Virgen Macarena
Seville, , Spain
Countries
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Central Contacts
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Trial questions or participation questions: 1-877-CTLILLY (1-877-285-4559) or
Role: CONTACT
Phone: 1-317-615-4559
Email: [email protected]
Physicians interested in becoming principal investigators please contact
Role: CONTACT
Email: [email protected]
Facility Contacts
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Role: primary
Role: primary
Role: primary
Role: primary
Other Identifiers
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J6M-OX-JSGA
Identifier Type: OTHER
Identifier Source: secondary_id
STX-478-101
Identifier Type: OTHER
Identifier Source: secondary_id
2023-000442-41
Identifier Type: EUDRACT_NUMBER
Identifier Source: secondary_id
2023-504807-94-00
Identifier Type: CTIS
Identifier Source: secondary_id
27691
Identifier Type: -
Identifier Source: org_study_id