ClinicalTrials.gg
Active, not recruitingNCT03313778KEYNOTE-603Updated Sep 3, 2026

Safety, Tolerability, and Immunogenicity of mRNA-4157 Alone and in Combination in Participants With Solid Tumors

A Phase 1 interventional study of mRNA-4157 and Pembrolizumab in Solid Tumors, sponsored by ModernaTX, Inc.. Active, not recruiting at 20 sites in 4 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-09-03.

Sponsored by ModernaTX, Inc. (part of Moderna, Inc.) · Phase 1, Interventional, and Treatment

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Phase
Phase 1
Study type
Interventional
Enrollment
161
Allocation
Non-randomized
Ages
18 Years and older
Sex
All
01

Study summary

The purpose of this study is to assess the safety, tolerability, and immunogenicity of mRNA-4157 alone and in combination in participants with solid tumors.

Read the detailed description

This is a multi-part, dose-escalation study of mRNA-4157 monotherapy in participants with resected solid tumors (Part A), mRNA-4157 monotherapy lead-in and then in combination with standard of care (SoC) adjuvant chemotherapy followed by mRNA-4157 monotherapy in participants with resected pancreatic ductal adenocarcinoma (PDAC) (Part A2), mRNA-4157 in combination with pembrolizumab in participants with both unresectable (locally advanced or metastatic) solid tumors (Parts B and C) and adjuvant resected cutaneous melanoma (Part D), and mRNA-4157 in combination with pembrolizumab and SoC chemotherapy in peri-operative setting in participants with non-squamous non-small cell lung cancer (NSCLC) (Part E1), squamous cell NSCLC (Part E2), and gastric/ gastroesophageal (GEJ) cancer (Part E3). Parts A and B will include a dose escalation phase of the study to identify doses of mRNA-4157 for the expansion phase of the study. Doses of mRNA-4157 will be administered to participants in a dose escalation regimen. Participants in Parts A2, B, C, D, E1, E2 and E3 dose expansion phase will receive mRNA-4157 at a recommended dose for expansion.

02

Conditions studied

  • Solid Tumors

Keywords

  • mRNA-4157
  • PCV
  • pembrolizumab
  • Moderna
  • intismeran autogene
03

In context

Lead sponsor

ModernaTX, Inc. is the lead sponsor of 119 studies on the registry; 18 are open to participants now.

Of its 64 completed or terminated interventional studies of FDA-regulated products, 35 (55%) have results posted.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years and older
Sexes eligible
All
Accepts healthy volunteers
No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • Parts A, A2, and D: Participants must be clinically disease-free at study entry (that is, participants in the setting).
  • Part B: Participants must have one of the - or cytologically-confirmed unresectable (locally advanced or ) protocol-specified solid , have at study entry defined by 1.1., and be considered suitable for treatment with pembrolizumab; in this study pembrolizumab will be considered an study drug.
  • Part C: Participants must have one of the histologically- or cytologically confirmed unresectable (locally advanced or metastatic) protocol-specified solid malignancies, must not have received prior anti-programmed cell death protein 1 ()/programmed death -ligand 1 (PD-L1) therapy, and must have measurable disease at study entry defined by RECIST 1.1.
  • Part A2: Participants with histologically confirmed PDAC who have undergone complete macroscopic resection(that is, R0 - no cancer cells within 1 mm of all resection margins or R1 - cancer cells present within 1 mm of one or more resection margins) who had no evidence of metastatic disease with adequate recovery from surgery to receive adjuvant therapy.
  • Parts E1 and E2: Participants with untreated histologically/cytologically confirmed Stage II-IIIB NSCLC (per AJCC version 8) that is considered resectable of non-squamous (adenocarcinoma only) or squamous cell carcinoma histology, absence of major associated pathologies that increase the surgery risk to an unacceptable level, must have a tumor tissue sample available for NGS and PD-L1 IHC testing as defined in the Laboratory Manual.
  • Part E3: Participants with untreated, locally advanced surgically resectable, histologically/cytologically confirmed, gastric/GEJ adenocarcinoma, as defined by a primary lesion that is T3 or greater or with the presence of any positive clinical nodes (N+) and without evidence of metastatic disease, measurable disease according to RECIST version 1.1, absence of major associated pathologies that increase the surgery risk to an unacceptable level, must have a tumor tissue sample available for NGS and PD-L1 IHC testing as defined in the Laboratory Manual.
  • Part D: Participants with completely resected Stage II, III or IV cutaneous melanoma.
  • Parts A, A2, and D: Participants must have a formalin-fixed paraffin embedded (FFPE) tumor sample available (for example, from their prior surgery) that is suitable for the next generation sequencing (NGS) required for this study.
  • Parts B and C: Participants must have at least 1 lesion amenable to the mandatory fresh tumor at study entry.
  • Participants must have resolution of toxic effect(s) (as specified in the protocol) from prior therapy to Grade 1 or less.
  • Participant is willing to use an adequate method of for the course of the study through 120 days after the last dose of study drug (male and female participants of ), or for a specified time after the last dose of SoC chemotherapy per SoC product labeling, whichever is later.
  • Participants with Performance Scale (PS) of 0 or 1 on the (ECOG) PS.

Exclusion criteria

Exclusion Criteria:

  • Treatment with any of the following:

    1. Any agents, anti-cancer monoclonal antibody, anti-cancer therapeutic vaccine, immunostimulant (for example, IL-2), or study drugs from a previous clinical study within 4 weeks of the first dose of mRNA-4157 or pembrolizumab (note only a 2 week wash out is required from prior pembrolizumab treatment)
    2. Any chemotherapy, targeted small molecule therapy, or radiation therapy within 2 weeks of the first dose of mRNA-4157 or pembrolizumab
    3. Live-virus vaccination within 30 days of the first dose of mRNA-4157 or pembrolizumab. Seasonal flu vaccines that do not contain live virus are permitted.
    4. Any systemic therapy or other form of therapy within 7 days of the first dose of mRNA-4157 or pembrolizumab
    5. Transfusion of blood products (including or red blood cells [RBCs]) or administration of colony stimulating factors (including granulocyte colony stimulating factor [G-CSF], granulocyte/macrophage colony stimulating factor [GM-CSF], or recombinant erythropoietin) within 1 week of the NGS blood sample during screening, and 4 weeks of the first dose of mRNA-4157 or pembrolizumab
  • A history or current evidence of any condition, therapy, or laboratory abnormality that might confound the results of the study, interfere with participation for the full duration of the study, or is not in the best interest of the participant to participate, in the opinion of the treating Investigator
  • Known psychiatric or substance abuse disorders that would interfere with cooperation with the requirements of the trial
  • Previously identified to chemotherapy agents that the participant would receive in their specific cohort or to components of the formulations used in this study
  • Known additional that is progressing or requires active treatment, exceptions include basal cell carcinoma of the skin, squamous cell carcinoma of the skin that has undergone curative therapy, or in situ cervical cancer.

Note: Additional inclusion/exclusion criteria may apply, per protocol.

Terms in these criteria, in plain language(16)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Adjuvant and neoadjuvant

Neoadjuvant treatment is given before the main treatment (usually surgery), often to shrink a tumour. Adjuvant treatment is given after it, to lower the chance of the cancer coming back.

Histologically or cytologically confirmed

The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).

Your pathology report is the document that shows this.

Metastases

Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.

Cancer (malignancy)

Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.

Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.

Measurable disease

The amount of disease can be tracked with a defined measurement, so the study can see whether it shrinks or grows. It might be a tumour measured on a scan or, in some blood cancers such as myeloma, a marker measured in blood or urine.

The criteria or the study team say which measurement counts — having no tumour visible on a scan does not by itself rule you out.

RECIST

The standard rules for measuring tumours on CT or MRI scans, to tell whether a cancer is shrinking, stable or growing during treatment.

“Measurable disease per RECIST 1.1” usually means at least one tumour 10 mm or more at its longest on a CT scan, or a lymph node 15 mm or more across its short axis.

Investigational drug or device

A drug or device being studied in a clinical trial.

It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.

PD-1, PD-L1 and checkpoint inhibitors

PD-1, PD-L1 and CTLA-4 are proteins that act as brakes on the immune system. Checkpoint inhibitors, such as pembrolizumab or nivolumab, block them so the immune system can attack a cancer.

PD-L1 can also be measured in a tumour sample. Some scores count stained tumour cells only (TPS); others also count certain immune cells (CPS). The study names the score and the minimum it uses.

Biopsy and archival tissue

A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.

Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.

Contraception

Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.

Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.

Childbearing potential

Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).

Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.

ECOG performance status

A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.

0
Fully active, no restrictions.
1
Limited in strenuous activity, but walking and able to do light work, such as housework or office work.
2
Walking and able to look after yourself, but unable to work; up and about more than half of waking hours.
3
Able to look after yourself only in part; in bed or a chair more than half of waking hours.
4
Unable to look after yourself at all; in bed or a chair all day.

Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.

Corticosteroids (steroids)

Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.

Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.

Immunosuppression

A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.

Read whether the line is about a condition or about medicines, and which medicines and doses it means.

Platelets

Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.

Hypersensitivity

An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.

05

Study design

Phase
Phase 1
Primary purpose
Treatment
Allocation
Non-randomized
Intervention model
Sequential assignment
Masking
None (open label)
Enrollment
161 participants (actual)

Study arms

  • Experimental
    Part A: Dose Escalation and Dose Expansion

    Participants will receive mRNA-4157 via an intramuscular (IM) injection on Day 1 of each 21-day cycle for up to 9 cycles.

    Biological: mRNA-4157

  • Experimental
    Part B: Dose Escalation and Dose Expansion

    Participants will receive mRNA-4157 via an IM injection on Day 1 of each 21-day cycle for up to 9 cycles and pembrolizumab via IV infusion on Day 1 of each 21-day cycle until progression, unacceptable toxicity, or up to 35 cycles (approximately 2 years of treatment), whichever is sooner.

    Biological: mRNA-4157 · Biological: Pembrolizumab

  • Experimental
    Part A2: Dose Expansion

    Participants will receive mRNA-4157 via an IM injection on Day 1 of each 21-day cycle and a SoC treatment every 2 weeks (Q2W) on Day 1 of each 21-day cycle starting from Cycle 5 of mRNA-4157 for up to 12 cycles.

    Biological: mRNA-4157 · Biological: SoC Treatment

  • Experimental
    Part C: Dose Expansion

    Participants will receive mRNA-4157 via IM injection on Day 1 of each 21-day cycle for up to 9 cycles and pembrolizumab via IV infusion on Day 1 of each 21-day cycle until progression, unacceptable toxicity, or up to 35 cycles (approximately 2 years of treatment), whichever is sooner.

    Biological: mRNA-4157 · Biological: Pembrolizumab

  • Experimental
    Part D: Dose Expansion

    Participants will receive mRNA-4157 via IM injection on Day 1 of each 21-day cycle for up to 9 cycles and pembrolizumab via IV infusion on Day 1 of each 21-day cycle until progression, unacceptable toxicity, or up to 18 cycles (approximately 1 year of treatment), whichever is sooner.

    Biological: mRNA-4157 · Biological: Pembrolizumab

  • Experimental
    Part E1: Dose Expansion

    Participants will receive mRNA-4157 via IM injection on Day 1 of each 21-day cycle, pembrolizumab every 6 weeks (Q6W) via IV infusion, and SoC chemotherapy every 3 weeks (Q3W) for up to 4 cycles during the perioperative and adjuvant phases.

    Biological: mRNA-4157 · Biological: Pembrolizumab · Biological: SoC Treatment

  • Experimental
    Part E2: Dose Expansion

    Participants will receive mRNA-4157 via IM injection on Day 1 of each 21-day cycle, pembrolizumab Q6W via IV infusion, and SoC chemotherapy Q3W for up to 4 cycles during the perioperative and adjuvant phases.

    Biological: mRNA-4157 · Biological: Pembrolizumab · Biological: SoC Treatment

  • Experimental
    Part E3: Dose Expansion

    Participants will receive mRNA-4157 via IM injection on Day 1 of each 21-day cycle, pembrolizumab Q3W via IV infusion, and SoC chemotherapy Q2W or Q3W for up to 4 cycles during the perioperative and adjuvant phases.

    Biological: mRNA-4157 · Biological: Pembrolizumab · Biological: SoC Treatment

Interventions

  • BiologicalmRNA-4157

    IM injection

  • BiologicalPembrolizumab

    Intravenous infusion

  • BiologicalSoC Treatment

    Intravenous infusion

    Also known as: Standard of care chemotherapy

06

What researchers measure

Primary outcomes

  1. Number of Participants with Adverse Events

    Time frame: Part A and A2: Baseline through 100 days after last mRNA-4157 dose; Parts B, C, D, E1, E2, and E3: Baseline through 90 days after last pembrolizumab dose

Secondary outcomes

  1. Part C: Overall Response Rate (ORR): Number of Participants with Tumor Response (Partial or Complete)

    ORR is defined as the proportion of participants whose best overall response is complete response (CR) or partial response (PR).

    Time frame: Baseline through disease progression by Response Evaluation Criteria of Solid Tumors Version 1.1 (RECIST 1.1), start of new anti-cancer therapy, withdrawal of consent, death and last safety follow-up visit (up to approximately 3 years)

  2. Part C: Duration of Response (DoR)

    DoR is defined as time from first tumor response (partial or complete) until either radiological disease progression, clinical/symptomatic disease progression or death (whichever is sooner).

    Time frame: Baseline through disease progression by RECIST 1.1, start of new anti-cancer therapy, withdrawal of consent, death and last safety follow-up visit (up to approximately 3 years)

  3. Part C: Progression Free Survival (PFS)

    PFS is defined as time between the date of first dose of pembrolizumab and the date of either radiological disease progression, clinical/symptomatic disease progression or death (whichever is sooner).

    Time frame: Baseline through disease progression by RECIST 1.1, start of new anti-cancer therapy, withdrawal of consent, death and last safety follow-up visit (up to approximately 3 years)

  4. Part C: Overall Survival (OS)

    OS is defined as time between the date of the first dose of study drug and the date of death due to any cause.

    Time frame: Baseline to death of any cause (up to approximately 3 years)

  5. Part A2: Recurrence-free Survival (RFS)

    RFS is defined as the time between the date of first dose of mRNA-4157 and the date of one of the following events: radiological disease relapse, clinical/symptomatic disease progression as assessed by the investigator or death due to any cause.

    Time frame: Baseline up to 2 years

  6. Parts A2, E1, E2, and E3: Number of Participants with Presence or Absence of Circulating Tumor DNA (ctDNA)

    Presence or absence of ctDNA prior to start of treatment as well as across longitudinal study timepoints, and association with RFS.

    Time frame: Baseline up to 2 years

  7. Parts E1 and E2: Event-free Survival (EFS)

    EFS is defined as the time from date of the first dose of study drug to the first of the following events: radiographic disease progression, local progression precluding surgery, inability to resect the tumor, local, regional, or distant recurrence, or death due to any cause and will be determined either by biopsy assessed by local pathologist or by investigator-assessed imaging using Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1.

    Time frame: Baseline up to 2 years

  8. Part E3: EFS

    EFS, based on RECIST 1.1, is defined as the time from date of the first dose of study drug to the first of the following events: radiographic disease progression per RECIST 1.1; local, regional or distant recurrence as assessed by computed tomography scan or biopsy if indicated (for participants who are disease free after surgery); clinical progression as evidenced by peritoneal carcinomatosis confirmed by preoperative laparoscopy or laparotomy (for participants who are confirmed to be free of peritoneal involvement by laparoscopy at screening); or death due to any cause.

    Time frame: Baseline up to 2 years

07

Study locations

20 sites
08

References and documents

Publications

  • Berraondo P, Cuesta R, Sanmamed MF, Melero I. Immunogenicity and Efficacy of Personalized Adjuvant mRNA Cancer Vaccines. Cancer Discov. 2024 Nov 1;14(11):2021-2024. doi: 10.1158/2159-8290.CD-24-1196. PubMed 39485256 ↗

Individual participant data

Plan to share: No

09

Timeline

Tracking since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reached

Started Aug 2017 (actual). Primary completion is estimated for Nov 2027, 123 months after the start.

How these figures are worked out, and which studies are left out of them.

Registered
Oct 13, 2017
First posted
Oct 18, 2017
StartActual
Aug 14, 2017
Primary completionEst.
Nov 21, 2027
CompletionEst.
Nov 21, 2027
Last update
Sep 3, 2026
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on Sep 3, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT03313778
Lead sponsor
ModernaTX, Inc.
Responsible party
Sponsor
First posted
Oct 18, 2017
Start date
Aug 14, 2017
Primary completion
Nov 21, 2027 (estimated)
Completion
Nov 21, 2027 (estimated)
Last update
Sep 3, 2026

Oversight

Data monitoring committee
No
FDA-regulated drug
Yes
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is active, not recruiting, as verified in Aug 2026. You cannot join it, but the record below documents what was studied.

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Discussion

Questions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.

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Studies of the drug tested here: Intismeran autogene

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