NCT07767474 · Antares Therapeutics, Inc
A Study to Evaluate ATX-898 in Participants With Advanced Solid Tumors
What this study is about
Study ATX-898-101 is a phase 1/2 where both patients and doctors know the treatment given study evaluating the safety, tolerability, how the drug moves through the body, and preliminary effectiveness of ATX-898 as treatment given alone and in combination with anti-neoplastic agents in selected solid tumors. This study consists of 2 parts.
View original scientific description
Study ATX-898-101 is a phase 1/2 open-label study evaluating the safety, tolerability, pharmacokinetic, and preliminary efficacy of ATX-898 as monotherapy and in combination with anti-neoplastic agents in selected solid tumors. This study consists of 2 parts. Part 1 evaluates ATX-898 as monotherapy and Part 2 evaluates ATX-898 in combination with anti-neoplastic agents of interest. Both parts will consists of a dose escalation portion and a dose expansion portion.
Interventions
DRUG
ATX-898
Doses defined per protocol
DRUG
ATX-898
RDE
DRUG
ATX-898
RDE
DRUG
ATX-898
RDE
DRUG
ATX-898
Doses defined per protocol
DRUG
ATX-898, fulvestrant, ribociclib
ATX-898 at RDE, Fulvestrant and abemaciclib: doses defined per protocol
DRUG
ATX-898, fulvestrant, ribociclib
ATX-898 at RDE, Fulvestrant and abemaciclib: doses defined per protocol
DRUG
ATX-898, fulvestrant, ribociclib
Doses defined per protocol
Primary outcome measures
Part 1a monotherapy dose escalation - Occurrence of Dose limiting toxicities (DLTs)
Time frame: 12 months
Toxicities occurring within the first treatment cycle (28 days). DLTs will be assessed in severity by the investigators per CTCAE v 6.0
Part 1a monotherapy dose escalation - Maximally tolerated/tested dose (MTD)
Time frame: 12 months
Maximum dose deemed safe and well tolerated during dose escalation
Part 1a monotherapy dose escalation - Recommended dose for expansion (RDE)
Time frame: 12 months
Monotherapy dose recommended to test during dose expansion
Part 1a monotherapy dose escalation - Treatment emergent adverse events (TEAEs)
Time frame: 12 months
Any adverse event (AE) either reported for the first time or worsening of a pre-existing event after first dose of study drug.
Part 1b monotherapy dose expansion - Objective Response Rate (ORR)
Time frame: 24 months
Percentage of participants with confirmed CR or PR per RECIST 1.1
Part 2a combination dose escalation - Occurrence of Dose limiting toxicities (DLTs)
Time frame: 18 months
Toxicities occurring within the first treatment cycle of combination therapy (28 days). DLTs will be assessed in severity by the investigators per CTCAE v 6.0
Part 2a combination dose escalation - Maximally tolerated/tested dose (MTD)
Time frame: 18 months
Maximum dose deemed safe and well tolerated during dose escalation of with combination treatment
Part 2a combination dose escalation - Recommended dose for expansion (RDE)
Time frame: 18 months
Recommended dose for expansion (RDE) Monotherapy dose recommended to test during dose expansion of combination treatment 18 months
Part 2a combination dose escalation - Treatment emergent adverse events (TEAEs)
Time frame: 18 months
Any adverse event (AE) either reported for the first time or worsening of a pre-existing event after first dose of study drug. 18 months
Part 2b combination dose expansion - Objective Response Rate (ORR)
Time frame: 36 months
Percentage of participants with confirmed CR or PR per RECIST 1.1
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Has histologically or cytologically confirmed advanced solid tumor malignancy that is metastatic or locally advanced and unresectable
- Is ≥18 years of age at the time of signing the informed consent form
- ECOG performance status score of 0 or 1
- Adequate organ function
- Must consent to a pre-treatment tumor biopsy (collected during screening or have available archival tumor tissue in the past 5 years. For Part 1a (monotherapy dose escalation)
- Has received one or more standard systemic therapies and additional standard therapies are either not available, or participant ineligible for available standard therapies For Part 1b (monotherapy dose expansion)
- b1: Has platinum-resistant or refractory metastatic ovarian cancer
- b2: Has recurrent or metastatic gynecologic cancer excluding the cancers eligible for b1
- b3: Has recurrent advanced or metastatic solid tumor excluding the cancers eligible for b1 or b2
- Has at least 1 measurable lesion per RECIST 1.1 For Part 2a (combination dose escalation)
- Has confirmed HR+ HER2 - (including HER2 low and ultra low) status
- Has received prior therapy in the metastatic For Part 2b (combination dose expansion)
- Has confirmed HR+ HER2 - (including HER2 low and ultra low) status
- Treatment-naïve or has received prior therapy in the metastatic setting
Exclusion criteria
- Has history (within ≤2 years before screening) of a solid tumor or hematological malignancy that is histologically distinct from the cancer being studied
- Has symptomatic CNS metastases at screening or asymptomatic CNS metastases requiring corticosteroids to control symptoms within 28 days prior to the first dose of ATX-898.
- Has toxicities from previous anticancer therapies that have not resolved to baseline levels or to CTCAE Grade ≤1, with the exception of alopecia any grade and Grade ≤2 peripheral neuropathy
- Has any condition for which, in the opinion of the Investigator, participation would not be in the best interest of the participant or would prevent, limit, or confound the protocol-specified assessments Cohort Specific:
- For abemaciclib cohorts only: has a history of any events of cardiac etiology that would contraindicate dosing with abemaciclib
- For ribocicilib only: has history of pneumonitis or interstitial lung disease
Where
- Fort Worth, Texas
- Houston, Texas
- San Antonio, Texas
- West Valley City, Utah
- Fairfax, Virginia
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Oct 16, 2026 · Source of record for eligibility and locations