NCT06840886 · Pheast Therapeutics
A Study of PHST001 in Advanced Solid Tumors
What this study is about
This is a multi-center, first-in-human (FIH), where both patients and doctors know the treatment given, Phase 1a/1b gradually increasing doses and dose expansion study to assess the safety, PK, how the drug affects the body, and antitumor activity of PHST001 treatment given alone (Phase 1a) or in combination with chemotherapy (Phase 1b) in adult participants with advanced relapsed and/or refractory solid tumors (including but not limited to CNS tumors in Phase 1a only). In Phase 1b group of participants expansions, the study will focus on participants with advanced relapsed and/or refractory ovarian cancer, endometrial cancer, and cholangiocarcinoma. The study's primary objective is to evaluate the safety and how well patients handle the treatment of PHST001 and determine the RP2D (Recommended Phase 2 dose) of PHST001 treatment given alone and in combination with chemotherapy as well as assess the anti-tumor activity of PHST001 and chemotherapy in Phase 1b.
View original scientific description
This is a multi-center, first-in-human (FIH), open-label, Phase 1a/1b dose escalation and dose expansion study to assess the safety, PK, pharmacodynamics, and antitumor activity of PHST001 monotherapy (Phase 1a) or in combination with chemotherapy (Phase 1b) in adult participants with advanced relapsed and/or refractory solid tumors (including but not limited to CNS tumors in Phase 1a only). In Phase 1b cohort expansions, the study will focus on participants with advanced relapsed and/or refractory ovarian cancer, endometrial cancer, and cholangiocarcinoma. The study's primary objective is to evaluate the safety and tolerability of PHST001 and determine the RP2D (Recommended Phase 2 dose) of PHST001 monotherapy and in combination with chemotherapy as well as assess the anti-tumor activity of PHST001 and chemotherapy in Phase 1b.
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
- Histologically or cytologically confirmed advanced solid tumor which has relapsed from or been refractory to all locally available standard therapies.
- Adequate organ function per laboratory testing
- Pregnancy prevention requirements
- Measurable disease per RECIST v1.1 (or RANO) as assessed by the local site Investigator/radiology
- Performance status of 0 or 1 on Eastern Cooperative Oncology Group (ECOG) scale Key
Exclusion criteria
- Diagnosis of immunodeficiency
- History of a previous additional malignancy, unless potentially curative treatment has been completed, with no evidence of malignancy for 5 years. Participants with basal cell carcinoma of the skin, Stage I melanoma, melanoma in situ, squamous cell carcinoma of the skin, early-stage prostate cancer, or carcinoma in situ, excluding carcinoma in situ of the bladder, who have undergone potentially curative therapy are not excluded and can be enrolled regardless of disease-free period following completion of potentially curative therapy. Participants with early-stage breast cancer who have undergone curative intent treatment and with no disease recurrence for 2 years after treatment are not excluded.
- Active known CNS metastases and/or carcinomatous meningitis. Participants with previously treated CNS metastases may participate provided they are radiologically stable (i.e., without evidence of progression for at least 2 weeks by repeat imaging \[note that the repeat imaging should be performed during study screening\]), clinically stable, and without requirement of steroid treatment for at least 14 days prior to the first dose of study treatment.
- Received prior systemic anticancer therapy including investigational agents within 21 days or, if shorter, within 5 half-lives prior to the first dose of study treatment. Participants must have recovered from all AEs due to previous therapies to Grade ≤1 or baseline. Participants with Grade ≤2 neuropathy may be eligible. Participants with endocrine-related AEs Grade ≤2 requiring treatment or hormone replacement may be eligible.
- Prior autologous or allogeneic hematopoietic stem cell transplant or solid organ transplant.
- Received previous treatment with another agent targeting CD24.
Where
- Beverly Hills, California
- Los Angeles, California
- Palo Alto, California
- Denver, Colorado
- New Haven, Connecticut
- Chicago, Illinois
- Boston, Massachusetts
- Ann Arbor, Michigan
- Grand Rapids, Michigan
- Lake Success, New York
- New York, New York
- Durham, North Carolina
And 6 more locations — see the full list below.
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 Jun 23, 2026 · Source of record for eligibility and locations