RecruitingPhase 1

A Study of PHST001 in Advanced Solid Tumors

An Open-label, Phase 1a/1b, Dose Escalation and Dose Expansion Study Investigating the Safety, Pharmacokinetics, Pharmacodynamics, and Antitumor Activity of PHST001 in Adult Patients With Advanced Relapsed and/or Refractory Solid Tumors

Who can join

As published by the study on ClinicalTrials.gov. "Not stated" means the study hasn't said — ask the study team.

Age
18 Years and older
Sex
All sexes
Healthy volunteers
Not accepted
Compensation
Not stated

Other requirements are listed under Eligibility below. Only the study team can confirm whether you can join.

What to expect

No one can promise a trial will help you personally — that is what the research is trying to find out.

What participation involves

Not stated in the study description — ask the study team about visits and procedures.

Compensation
Not stated
  • Study-related exams and procedures are typically provided at no cost. This is how many trials work in general — confirm the details for this study with the study team.
  • Participants are monitored closely by the research team throughout the study.
  • Some participants may receive access to an investigational treatment, which is still being studied.
  • Your participation helps researchers learn whether this approach could help future patients.

About this study

In plain language

This study tests PHST001 alone or with other cancer drugs in adults with advanced solid tumors that came back or did not respond to standard treatments. Researchers will check its safety, find a dose for future studies, and see how well it works against cancer.

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 anticancer therapies (Phase 1b) in adult participants with advanced relapsed and/or refractory solid tumors (including but not limited to CNS tumors in Phase 1a only). Phase 1b will include the following cohorts 1) tumor-specific cohorts for participants with advanced relapsed and/or refractory ovarian cancer, endometrial cancer, and cholangiocarcinoma, 2) a randomized cohort for participants with ovarian cancer who will receive PHST001 in combination with mirvetuximab soravtansine, 3) a cohort for participants with advanced/metastatic breast cancer who will receive PHST001 in combination with trastuzumab deruxtecan and 4) a cohort of patients who consent to additional biomarker studies. The study's primary objectives are to evaluate the safety and tolerability of PHST001 and determine the RP2D (Recommended Phase 2 dose) of PHST001 as monotherapy and in combination with anticancer therapies, as well as to assess the anti-tumor activity of PHST001 in combination with anticancer therapies in Phase 1b.

Compensation is read from the study's own description and may be missing — always confirm with the study team.

Eligibility

Who can join

  • You are an adult with an advanced solid tumor confirmed by testing tissue or cells.
  • Your cancer came back or did not respond to all standard treatments available locally.
  • Lab tests show that your organs work well enough.
  • You meet the study's pregnancy prevention rules.
  • Your cancer can be measured on scans using the study's rules.
  • You can do all usual activities, or can do light activities but not hard physical tasks.

Who can't join

  • You have a condition that weakens your immune system.
  • You had another cancer, unless treatment meant to cure it is complete and you have been cancer-free for 2 years. Some early-stage or low-risk cancers have exceptions.
  • Cancer from elsewhere in your body has spread to your brain, spinal cord, or their lining and is active. Treated, stable spread may be allowed if you meet scan and steroid-use rules.
  • You received cancer drugs too recently before study treatment: within 21 days, or a shorter period based on how long the drug stays in your body.
  • You still have more than mild side effects from earlier treatment that have not returned to your usual level. Some nerve or hormone-related side effects may be allowed.
  • You have had a blood-forming stem cell transplant or an organ transplant.
  • You have already received a drug that targets CD24.

Simplified for readability. The official criteria below are what the study team uses.

Official eligibility criteria

Key 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 2 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, low grade neoplasms, 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 from a systemic (non-CNS) primary malignancy. Participants with previously treated CNS metastases are eligible, provided they are radiologically and clinically stable (i.e., no evidence of progression for at least 2 weeks by repeat imaging performed during screening) and are not requiring systemic corticosteroids above the physiologic replacement for at least 7 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.

Study sites (20)

CA

CO

CT

IL

MA

MI

NC

NY

TN

TX

VA