Pembrolizumab and Gemcitabine Chemotherapy in Leiomyosarcoma and Undifferentiated Pleomorphic Sarcoma

NCT03123276 | Completed Phase 1 Results DMC

• 1 other identifier: CCR 4541
• Study Type: interventional
• Target: 25
• Locations: 1 country
• Sites: 1

Brief Summary

Soft tissue sarcomas (STS) are a group of rare mesenchymal neoplasms affecting all ages. STS most commonly present as localised disease but despite surgery and adjuvant treatment more than half of patients will develop recurrent or metastatic disease. Leiomyosarcoma (LMS), a malignancy of smooth muscle, is one of the most common STS and undifferentiated pleomorphic sarcoma (UPS) is a common sarcoma sub-type with aggressive symptoms. Recent studies have demonstrated reasonable sensitivity of LMS to gemcitabine monotherapy with an objective response rate of 8-19%. However the overall survival is still only about 12 months which illustrates the critical clinical need for improved therapies for advanced STS and sarcoma in general. In this study the investigators propose to combine the immune synapse checkpoint inhibitor with the cytotoxic and immune modulating agent, gemcitabine. It is hoped that this dual immunomodulatory approach will enhance the effect of pembrolizumab on PD-L1 expressing LMS and UPS, leading to a safe treatment with patient outcomes. This is a two part, phase I, single centre dose escalation and dose expansion study in the total of 24 patients with newly diagnosed metastatic or inoperable LMS and UPS. There will be approximately 12 patients in the dose escalation cohort (part A) and the starting dose will be a fixed dose rate (FDR) gemcitabine of 800 mg/m2 on day 1 and 8 of 21 days cycles in combination of 200 mg of pembrolizumab given as an infusion on day 1 every 3 weeks. The MTD cohort (part B) will then be expanded to a total of 12 patients in order to further evaluate the safety and tolerability of that dose as well as to preliminarily assess response to therapy. The study is sponsored by Royal Marsden NHS Foundation trust and the funding for the study is provided by Merck Sharp \& Dohme Limited.

Conditions

Sarcoma

Outcome Measures

Primary Outcomes (1)

• Number of Patients With Dose Limiting Toxicities.

  Part A dose escalation part patients were treated cohorts and assessed for safety until the maximum tolerated dose of gemcitabine that can be safely combined with pembrolizumab in the absence of dose limiting toxicities (DLT). Outcome measure here is the proportion of patients with DLT for each dose level. Protocol definition of DLT: (1) Neutropenia \<0.5 x 109/L for \>5 days. This must be confirmed with repeat blood tests at the Royal Marsden Hospital within 6 days of the diagnosis of neutropenia. (2) Febrile neutropaenia as per definition by ESMO (\>38.3°C or two consecutive readings of \>38.0°C for 2 hours and an absolute neutrophil count (ANC) of \<0.5 x 109/L or expected to fall below \<0.5 x 109/L). (3) Thrombocytopenia \<25 x 109/L. (4) Any non-haematological CTCAE Grade 3 or 4 toxicity that is, in the opinion of the investigator, clinically significant. All the above must be in the investigator's opinion, likely to be causally linked with the administration of Gemcitabine.

  Treatment start date until completion of 1 full cycle of treatment (21 days)

Secondary Outcomes (1)

• Preliminary Evaluation of Response by Using RECIST v1.1. Number of Patients With Objective Response and Disease Control

  Treatment initiation until 9 weeks of starting treatment

Study Arms (1)

gemcitabine + pembrolizumab

EXPERIMENTAL

First cohort of 6 patients may receive Gemcitabine 800 mg/m2 + Pembrolizumab 200 mg. After safety data review, if no DLTs then dose for Gemcitabine will be increased to 1000 and further 1200 mg/m2.

Drug: Pembrolizumab; Drug: Gemcitabine

Interventions

Pembrolizumab DRUG

humanized IgG4 PD-1 blocking antibody

Also known as: Keytruda

gemcitabine + pembrolizumab

Gemcitabine DRUG

Doses of 800, 1000 and 1200 mg/m2 will be used in dose escalation phase.

gemcitabine + pembrolizumab

Eligibility Criteria

• Age: 18 Years - 99 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Have a histologically confirmed case of undifferentiated pleomorphic sarcoma or leiomyosarcoma and be willing to consent for archival tumour material to be requested for transfer to The Royal Marsden for future review.
• Have biopsiable disease and be willing to agree to a biopsy in order to permit acquisition of mandatory paired tumour biopsies done during screening and following 9 weeks of treatment for analysis of immunomodulation.
• Be willing and able to provide written informed consent/assent for the trial.
• Be over 18 years of age on day of signing informed consent.
• Have a performance status of 0 or 1 on the ECOG Performance Scale.
• Have measurable disease based on RECIST 1.1.
• Have a life expectancy of \>12 weeks
• Demonstrate adequate organ function as defined in the protocol, all screening labs should be performed within 28 days of treatment initiation.
• Female subject of childbearing potential should have a negative urine or serum pregnancy within 72 hours prior to receiving the first dose of study medication. If the urine test is positive or cannot be confirmed as negative, a serum pregnancy test will be required.
• Female subjects of childbearing potential (Section 5.7.2) must be willing to use an adequate method of contraception as outlined in Section 5.7.2 - Contraception, for the course of the study through 6 months after the last dose of study medication.
• Note: Abstinence is acceptable if this is the usual lifestyle and preferred contraception for the subject.
• Male subjects of childbearing potential (Section 5.7.1) must agree to use an adequate method of contraception as outlined in Section 5.7.1- Contraception, starting with the first dose of study therapy through 6 months after the last dose of study therapy.
• Note: Abstinence is acceptable if this is the usual lifestyle and preferred contraception for the subject.

You may not qualify if:

• Is currently participating and receiving study therapy or has participated in a study of an investigational agent and received study therapy or used an investigational device within 4 weeks of the first dose of treatment.
• Has a diagnosis of immunodeficiency or is receiving systemic steroid therapy or any other form of immunosuppressive therapy within 7 days prior to the first dose of trial treatment.
• Has a known history of active TB (Bacillus Tuberculosis)
• Hypersensitivity to pembrolizumab or any of its excipients.
• Has had a prior anti-cancer monoclonal antibody (mAb) within 4 weeks prior to study Day 1 or who has not recovered (i.e., ≤ Grade 1 or at baseline) from adverse events due to agents administered more than 4 weeks earlier.
• Has had prior chemotherapy, targeted small molecule therapy, or radiation therapy within 2 weeks prior to study Day 1 or who has not recovered (i.e., ≤ Grade 1 or at baseline) from adverse events due to a previously administered agent.
• Note: Subjects with ≤ Grade 2 neuropathy are an exception to this criterion and may qualify for the study.
• Note: If subject received major surgery, they must have recovered adequately from the toxicity and/or complications from the intervention prior to starting therapy.
• Has a known additional malignancy that is progressing or requires active treatment. Exceptions include basal cell carcinoma of the skin or squamous cell carcinoma of the skin that has undergone potentially curative therapy or in situ cervical cancer.
• Has known active central nervous system (CNS) metastases and/or carcinomatous meningitis. Subjects with previously treated brain metastases may participate provided they are stable (without evidence of progression by imaging for at least four weeks prior to the first dose of trial treatment and any neurologic symptoms have returned to baseline), have no evidence of new or enlarging brain metastases, and are not using steroids for at least 7 days prior to trial treatment. This exception does not include carcinomatous meningitis which is excluded regardless of clinical stability.
• Has active autoimmune disease that has required systemic treatment in the past 2 years (i.e. with use of disease modifying agents, corticosteroids or immunosuppressive drugs). Replacement therapy (eg., thyroxine, insulin, or physiologic corticosteroid replacement therapy for adrenal or pituitary insufficiency, etc.) is not considered a form of systemic treatment.
• Has known history of, or any evidence of active, non-infectious pneumonitis.
• Has an active infection requiring systemic therapy.
• Has a history or current evidence of any condition, therapy, or laboratory abnormality that might confound the results of the trial, interfere with the subject's participation for the full duration of the trial, or is not in the best interest of the subject to participate, in the opinion of the treating investigator.
• Has known psychiatric or substance abuse disorders that would interfere with cooperation with the requirements of the trial.

Sponsors & Collaborators

• Royal Marsden NHS Foundation Trust: lead
• Merck Sharp & Dohme LLC: collaborator

Study Sites (1)

Royal Marsden

London, United Kingdom

Location

MeSH Terms

Conditions

Sarcoma

Interventions

pembrolizumab; Gemcitabine

Condition Hierarchy (Ancestors)

Neoplasms, Connective and Soft Tissue; Neoplasms by Histologic Type; Neoplasms

Intervention Hierarchy (Ancestors)

Heterocyclic Compounds; Deoxycytidine; Cytidine; Pyrimidine Nucleosides; Pyrimidines; Heterocyclic Compounds, 1-Ring

Results Point of Contact

• Title: Clinical Trials Manager - Angelie Tirona
• Organization: The Royal Marsden NHS Foundation Trust

GEMMK.Trial@rmh.nhs.uk

020 8642 6011

Study Officials

• Robin Jones

  Royal Marsden NHS Foundation Trust

  PRINCIPAL INVESTIGATOR

Publication Agreements

• PI is Sponsor Employee: No
• Restrictive Agreement: No

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: NA
• Masking: NONE
• Purpose: OTHER
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: March 31, 2017
• First Posted: April 21, 2017
• Study Start: November 29, 2017
• Primary Completion: May 20, 2022
• Study Completion: May 20, 2022
• Last Updated: February 13, 2026
• Results First Posted: February 13, 2026

Record last verified: 2026-02

Data Sharing

• IPD Sharing: Will not share

Locations

GB (1)