SarcomaPhase 1NCT06113809
Palbociclib and Pembrolizumab in Sarcoma
A Phase 1 study testing Palbociclib and Pembrolizumab in people with Sarcoma, run by John Rieth at 1 site in United States.
Trial summary
This is a single-arm open-label window of opportunity clinical study assessing the impact of pre-treatment with palbociclib in patients with soft tissue sarcomas for which PD-1 inhibitors are approved (includes undifferentiated pleomorphic sarcoma, myxofibrosarcoma, angiosarcoma, pleomorphic rhabdomyosarcoma… Read more about this study
- Who is it for?
- Ages 12 years and older
- Conditions the study is for
- Sarcoma
- What is being tested?
- Palbociclib and Pembrolizumab
- Type of treatment
- Pill or oral medicine, Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 8 participants
- Where
- 1 siteUnited States
- Study dates
- 1 Feb 2024to Jul 2028
- Phase
- Phase 1
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 12 years and older
- All sexes
- No healthy volunteers
- Child, Adult, Older adult
Who may be able to join
- A potential subject must meet all the following inclusion criteria to be eligible to participate in the study:
- Male or female patients aged > or = 12 years old
- ECOG Performance Status of < or = 2
- Any patient with the diagnosis of locally advanced, unresectable or metastatic sarcoma for which PD-1 inhibitors are approved (undifferentiated pleomorphic sarcoma, myxofibrosarcoma, angiosarcoma, pleomorphic rhabdomyosarcoma, pleomorphic liposarcoma, alveolar soft part sarcoma) who have progressed on at least 1 prior line of therapy. Prior immunotherapy treatment is allowed, including prior treatment with a PD-1 inhibitor.
- Patients with no known CNS disease, except for treated brain metastasis. Treated brain metastases are defined as having no evidence of progression or hemorrhage after treatment and no ongoing treatment for dexamethasone (as ascertained by clinical examination and brain imaging) during the screening period. Stable dose of anticonvulsants is allowed. Treatment for brain metastases may include whole brain radiotherapy, radiosurgery, or a combination as deemed appropriate by the treating physician. Patients with CNS metastases treated by neurosurgical resection or brain biopsy performed within 3 months prior to Day 1 will be excluded.
- Ability to understand and the willingness to sign a written informed consent or assent in case of patients < 18 years old.
Who cannot join
- A potential subject who meets any of the following exclusion criteria is ineligible to participate in the study:
- Lab values in the below ranges:
- Neutrophil count < 1000/mm3
- Platelet count < 100,000/mm3L
- Hemoglobin < 9 g/dL (transfusion to meet eligibility allowed)
- AST/SGOT and ALT/SGPT > 3.0x upper limit of normal (ULN) without disease involvement or > 5.0x ULN if the transaminase elevation is due to disease involvement
Show all 21Show fewer
- Alkaline phosphatase > 5.0x ULN without known bony metastases
- Serum bilirubin > 1.5x ULN
- Serum creatinine > 1.5x ULN or 24-hour creatinine clearance < 30 mL/min per Cockroft- Gault equation
- Total serum calcium < lower limit of normal (LLN) or if calcium is below LLN the corrected calcium for serum albumin is > LLN
- Serum potassium < 3.0
- Serum sodium < 130
- Serum albumin < 2.5 g/dL
- History of myocardial infarction. unstable angina, stroke or transient ischemic attack within 6 months prior to Day 1
- History or drug induced pneumonitis (both pembrolizumab and palbociclib can cause pneumonitis)
- Subjects requiring hemodialysis
- Patients with severe hepatic impairment (Childs-Pugh Class C).
- Other concurrent severe and/or uncontrolled medical conditions in the opinion of the investigator which will preclude participation
- Pregnancy (positive pregnancy test) or lactation
- Concomitant use of any other anti-cancer therapy or radiation therapy of the target lesion. Palliative radiation therapy is permitted to non-target lesions.
- Patients with any significant history of non-compliance to medical regimens or with inability to grant a reliable informed consent
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
United States1 site, 1 recruiting
- Recruiting
University of Iowa Hospitals & Clinics
Iowa City, Iowa, 52242
John Rieth, MD, (319) 356-1616, john-rieth@uiowa.edu
About this study
Official title: Phase Ib Trial Evaluating the Combination of CDK4 Inhibitor With Immunotherapy in Patients With Sarcoma
This is a single-arm open-label window of opportunity clinical study assessing the impact of pre-treatment with palbociclib in patients with soft tissue sarcomas for which PD-1 inhibitors are approved (includes undifferentiated pleomorphic sarcoma, myxofibrosarcoma, angiosarcoma, pleomorphic rhabdomyosarcoma, pleomorphic liposarcoma, or alveolar soft part sarcoma).
Read the detailed description
Patients will be given palbociclib for 2 weeks following a pre-treatment ultrasound guided biopsy used to establish immunological baseline of the tumor microenvironment. After 2 weeks of palbociclib therapy, a second biopsy will be performed to assess the impact of palbociclib on the tumor microenvironment. Pembrolizumab will be started the same day as the second biopsy. After 2 doses of pembrolizumab, a third (optional) biopsy may be performed if the subject consents. At 8 weeks of therapy disease response will be assessed as per standard of care.
- Conditions
- Sarcoma
- Being tested
- Palbociclib, Pembrolizumab
- Medical subject headings
- Sarcoma
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
PalbociclibDrug
Palbociclib is a CDK4/6 inhibitor.
Palbociclib, 125 mg, (pediatric dose 75mg/m2 up to 125mg) daily for 21 days out of every 28 days, PO (orally) starting 14 days prior to Pembrolizumab
PembrolizumabDrug
Pembrolizumab is a PD-1 blocking antibody.
Given 14 days following Palbociclib: Pembrolizumab, 200 mg, once every three weeks, intravenously (IV)
| Study group | Role | What they receive |
|---|---|---|
| Combination of Palbociclib with Pembrolizumab | Experimental | Palbociclib given for 2 weeks following a pre-treatment ultrasound guided biopsy used to establish an immunological baseline of the tumor microenvironment. After the conclusion of palbociclib therapy, a post-treatment biopsy will be performed to assess the impact of palbociclib on the tumor microenvironment; pembrolizumab will be started the same day as the second biopsy. After 2 doses of pembrolizumab, a third (optional) biopsy could be performed. Receives: Drug: Palbociclib; Drug: Pembrolizumab |
What is being measured
The primary outcome is the main question the study is designed to answer.
Dose limiting toxicities (DLTs) and adverse events (AEs) per CTCAE v5
Confirm the safety of the combination of Palbociclib and pembrolizumab in sarcomas for which PD-1 inhibitors are approved as defined by the incidence of DLTs
Measured: The dose limiting toxicity period is 4 weeks after starting the first dose of pembrolizumab
Secondary outcomes (1)
Response rate per RECIST 1.1 criteria
To assess the response (per RECIST 1.1 criteria) of patients with advanced UPS with the combination of CDK4/6 inhibitor and anti-PD-1 immunotherapy
Measured: 8 weeks following treatment intiation
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted2 Nov 2023
- Study start1 Feb 2024
- Primary completionJul 2028 (estimated)
- Study completionJul 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for SarcomaStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 1
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Model description
- This is a single-arm open-label window of opportunity clinical study assessing the impact of pre-treatment with palbociclib
- Masking
- None (open label)
- Enrolment
- 8 participants (estimated)
Sponsor and investigators
- Lead sponsor
- John Rieth
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor-investigator, John Rieth, University of Iowa
- Investigators
- John Rieth, MD, Principal investigator, University of Iowa Hospitals & Clinics
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06113809
- Sponsor's protocol ID
- 202305133
- Status last verified
- May 2026
- First submitted
- 16 Oct 2023
- Last updated
- 22 May 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 22 May 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Phase Ib Trial Evaluating the Combination of CDK4 Inhibitor With Immunotherapy in Patients With Sarcoma
- ClinicalTrials.gov ID
- NCT06113809
- Acronym / sponsor ID
- 202305133
- Conditions
- Sarcoma
- Phase
- Phase 1
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 8 participants (estimated)
- Lead sponsor
- John RiethUniversity, hospital or other
- Study start
- 1 Feb 2024 (actual)
- Primary completion
- Jul 2028 (estimated)
- Study completion
- Jul 2028 (estimated)
- First posted
- 2 Nov 2023 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This is a single-arm open-label window of opportunity clinical study assessing the impact of pre-treatment with palbociclib in patients with soft tissue sarcomas for which PD-1 inhibitors are approved (includes undifferentiated pleomorphic sarcoma, myxofibrosarcoma, angiosarcoma, pleomorphic rhabdomyosarcoma, pleomorphic liposarcoma, or alveolar soft part sarcoma).
Detailed description
Patients will be given palbociclib for 2 weeks following a pre-treatment ultrasound guided biopsy used to establish immunological baseline of the tumor microenvironment. After 2 weeks of palbociclib therapy, a second biopsy will be performed to assess the impact of palbociclib on the tumor microenvironment. Pembrolizumab will be started the same day as the second biopsy. After 2 doses of pembrolizumab, a third (optional) biopsy may be performed if the subject consents. At 8 weeks of therapy disease response will be assessed as per standard of care.
Study design
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
- Model description
- This is a single-arm open-label window of opportunity clinical study assessing the impact of pre-treatment with palbociclib
| Arm | Type | Receives |
|---|---|---|
| Combination of Palbociclib with Pembrolizumab | Experimental | Drug: Palbociclib, Drug: PembrolizumabPalbociclib given for 2 weeks following a pre-treatment ultrasound guided biopsy used to establish an immunological baseline of the tumor microenvironment. After the conclusion of palbociclib therapy, a post-treatment biopsy will be performed to assess the impact of palbociclib on the tumor microenvironment; pembrolizumab will be started the same day as the second biopsy. After 2 doses of pembrolizumab, a third (optional) biopsy could be performed. |
Who may qualify
- Ages
- 12 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child, Adult, Older adult
Key inclusion criteria (6 listed)
- A potential subject must meet all the following inclusion criteria to be eligible to participate in the study:
- Male or female patients aged > or = 12 years old
- ECOG Performance Status of < or = 2
- Any patient with the diagnosis of locally advanced, unresectable or metastatic sarcoma for which PD-1 inhibitors are approved (undifferentiated pleomorphic sarcoma, myxofibrosarcoma, angiosarcoma, pleomorphic rhabdomyosarcoma, pleomorphic liposarcoma, alveolar soft part sarcoma) who have progressed on at least 1 prior line of therapy. Prior immunotherapy treatment is allowed, including prior treatment with a PD-1 inhibitor.
- Patients with no known CNS disease, except for treated brain metastasis. Treated brain metastases are defined as having no evidence of progression or hemorrhage after treatment and no ongoing treatment for dexamethasone (as ascertained by clinical examination and brain imaging) during the screening period. Stable dose of anticonvulsants is allowed. Treatment for brain metastases may include whole brain radiotherapy, radiosurgery, or a combination as deemed appropriate by the treating physician. Patients with CNS metastases treated by neurosurgical resection or brain biopsy performed within 3 months prior to Day 1 will be excluded.
Key exclusion criteria (21 listed)
- A potential subject who meets any of the following exclusion criteria is ineligible to participate in the study:
- Lab values in the below ranges:
- Neutrophil count < 1000/mm3
- Platelet count < 100,000/mm3L
- Hemoglobin < 9 g/dL (transfusion to meet eligibility allowed)
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| PalbociclibPalbociclib is a CDK4/6 inhibitor. Palbociclib, 125 mg, (pediatric dose 75mg/m2 up to 125mg) daily for 21 days out of every 28 days, PO (orally) starting 14 days prior to Pembrolizumab | Drug | Combination of Palbociclib with Pembrolizumab |
| PembrolizumabPembrolizumab is a PD-1 blocking antibody. Given 14 days following Palbociclib: Pembrolizumab, 200 mg, once every three weeks, intravenously (IV) | Drug | Combination of Palbociclib with Pembrolizumab |
Primary outcome
Dose limiting toxicities (DLTs) and adverse events (AEs) per CTCAE v5
Time frame: The dose limiting toxicity period is 4 weeks after starting the first dose of pembrolizumab
Confirm the safety of the combination of Palbociclib and pembrolizumab in sarcomas for which PD-1 inhibitors are approved as defined by the incidence of DLTs
1 secondary outcome
Response rate per RECIST 1.1 criteria
Time frame: 8 weeks following treatment intiation
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 22 May 2026.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
John Rieth, MD principal investigator
University of Iowa Hospitals & Clinics
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 1 study testing Palbociclib and Pembrolizumab in people with Sarcoma, run by John Rieth at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 6 inclusion and 21 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 22 May 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 1 studies test a treatment in a small group of people for the first time or in a new way, mainly to check safety and find the right dose.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact John Rieth, MD (3193561616, john-rieth@uiowa.edu), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Dose limiting toxicities (DLTs) and adverse events (AEs) per CTCAE v5 (time frame: The dose limiting toxicity period is 4 weeks after starting the first dose of pembrolizumab). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 22 May 2026.