ClinicalTrials.gg
RecruitingNCT06644755Updated Sep 4, 2026

First-in-Human Trial of DS-2243a in Participants With Advanced Solid Tumors

A Phase 1 interventional study of DS-2243a in Solid Tumors and Sarcoma, sponsored by Daiichi Sankyo. Recruiting at 7 sites in 5 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-09-04.

Sponsored by Daiichi Sankyo · Phase 1, Interventional, and Treatment

From the registry’s dates

  • Started Nov 2024; still recruiting 1 year 11 months later.
Phase
Phase 1
Study type
Interventional
Enrollment
150
Allocation
Not applicable
Ages
18 Years and older
Sex
All
01

Study summary

This 2-part study will evaluate safety, tolerability, and clinical efficacy of DS-2243a as a treatment for participants with advanced solid tumors.

Read the detailed description

This is a global, multicenter, open-label, first-in-human, Phase 1 trial of DS-2243a as a treatment for locally advanced or metastatic synovial sarcoma (SS), myxoid/round cell liposarcoma (MRCLS), squamous cell carcinoma type non-small cell lung cancer (Sq-NSCLC), adenocarcinoma type non-small cell lung cancer (Ad-NSCLC), or urothelial carcinoma (UC) participants with HLA-A2 and/or NY-ESO positive. The trial consists of 2 parts: the Dose Escalation Part (Part 1) and the Dose Expansion Part (Part 2).

02

Conditions studied

  • Solid Tumors
  • Sarcoma

Keywords

  • synovial sarcoma
  • ny-eso-1
  • DS-2243a
  • Myxoid Round cell Liposarcoma
  • sarcoma
  • NSCLC
  • UC
  • Bladder Cancer
  • NY-ESO
  • HLA-A2
  • Advanced solid tumors
03

In context

Sarcoma

1,607 studies on the registry are indexed under Sarcoma; 366 are open to participants now.

This study's planned enrollment of 150 is above the median of 40 across 1,255 interventional studies indexed under Sarcoma.

Browse Sarcoma studies →

Lead sponsor

Daiichi Sankyo is the lead sponsor of 322 studies on the registry; 37 are open to participants now.

Of its 51 completed or terminated interventional studies of FDA-regulated products, 38 (75%) 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

Eligibility criteria

Key Inclusion Criteria:

  1. Sign and date the main ICF.
  2. Adults ≥18 years at the time the biosample ICF or main ICF, whichever is signed first.

    Follow local regulatory requirements if the legal age of consent for trial participation is >18 years old.

  3. One of the following or cytologically documented cancers:

    Advanced ( or unresectable) SS Advanced (metastatic or unresectable) MRCLS Metastatic or unresectable locally advanced NSCLC (Ad/Sq) Metastatic or unresectable locally advanced UC

  4. from, refractory to, or intolerant to appropriate therapies [eg, standard of care (SOC) therapy] to provide clinical benefit for their condition as assessed by their physician and/or investigator. [For South Korea only: Relapsed from, refractory to, or intolerant to all available therapies (eg, SOC therapy domestically approved) for their condition.]
  5. HLA-A*02:01, 02:02, 02:03, 02:04, 02:05, 02:06, 02:09, 02:10, or 02:11 positive.
  6. Has based on v1.1 on computed tomography/magnetic resonance imaging (CT/MRI).
  7. Is willing and able to provide adequate pre-treatment or sample.
  8. Has Performance Status (ECOG PS) score of 0 or 1 at Screening.
  9. Meets the following required baseline local laboratory data within 14 days prior to start of trial intervention administration:

    1. (ALT) and aspartate aminotransferase (AST) ≤3 × (ULN) in participants with no liver metastasis, or ≤5 × ULN in participants with liver metastasis
    2. Total (TBL) ≤1.5 × ULN (≤3 × ULN for participants with a documented history of Gilbert's syndrome)
    3. (ANC) ≥1.5 × 10\^9/L
    4. count ≥100 × 10\^9/L
    5. ≥8 g/dL
    6. (CrCl) ≥45 mL/min as calculated using the Cockcroft-Gault equation (Section 10.3.1)

    Note: Any blood or blood product transfusion is allowed up to 7 days before the hematology evaluations and any dose of hematologic growth factor is allowed up to 14 days before the hematology evaluations.

  10. a) A female participant of (CBP), as defined in Section 10.3.5.1, is eligible to participate if the following conditions are met: Participant is not pregnant as confirmed by highly sensitive pregnancy test (see Section 10.3.5.3). Participant does not breastfeed during the trial intervention period and for at least 120 days after last dose of trial intervention. Participant agrees to adhere to a method that is highly effective (Section 10.3.5.2) and agrees not to donate eggs (ova, oocytes) to others or freeze/store eggs during the intervention period and for at least the time needed to eliminate the trial intervention after the last dose. The length of time required to continue contraception after last dose for the trial intervention is 120 days. Preservation of eggs may be considered prior to first dose of trial intervention.

    b) A male participant capable of producing sperm is eligible to participate if he agrees to the following during the Treatment Period and for at least the time needed to eliminate the trial intervention. The length of time required to continue contraception after the last dose of the trial intervention is 120 days.

    • Avoid donating sperm. Note: Preservation of sperm should be considered prior to enrollment/randomization in this trial.
    • Adhere to either of the following contraception methods:

      • True abstinence from penile-vaginal intercourse, when this is in line with the preferred and usual lifestyle of the participant, OR
      • Uses a penile/external condom when having penile-vaginal intercourse with a nonparticipant of childbearing potential (see Section 10.3.5) PLUS partner use of an additional contraceptive method (see Section 10.3.5.2), as a condom may break or leak. Contraceptive use should be consistent with local regulations regarding the methods of contraception for those participating in clinical studies. If the contraception requirements in the local label for any of the trial interventions are more stringent than the requirements above, the local label requirements are to be followed.

Note: If the participant is azoospermic (vasectomized or secondary to medical cause, documented from the site personnel's review of the participant's medical records, medical examination, or medical history interview), no contraception is required.

Key Exclusion Criteria:

  1. Has received prior therapy targeting NY-ESO-1.
  2. Has an inadequate treatment prior to the start of trial intervention, defined as follows:

    1. Radiation therapy: \<4 weeks (or \<2 weeks if palliative radiation therapy without abdominal/pelvic radiation)
    2. Chemotherapy, antibody-based anticancer therapy, immunotherapy: \<4 weeks
    3. Small molecules (eg, tyrosine kinase inhibitors): \<2 weeks or 5 half-lives, whichever is longer
  3. Has known symptomatic central nervous system (CNS) metastases, , or cord compression. Note: Asymptomatic or adequately treated are not exclusionary provided that, in the opinion of the investigator, the participant is neurologically stable.

    MRI/CT of the brain is required for all participants during Screening Period (see Section 8.3.1).

  4. Uncontrolled or cardiovascular disease, including the following:

    1. Myocardial infarction within 6 months prior to screening
    2. Uncontrolled angina pectoris within 6 months prior to screening
    3. (NYHA) Class III or IV congestive heart failure
    4. (LVEF) ≤50% or lower than the institutional lower limit of normal
    5. corrected with Fridericia's formula (QTcF) interval >480 ms
  5. Chronic treatment (IV or oral) or any other medication (ie, prednisone >10 mg daily (QD) or the equivalent).
  6. Has active other primary . Note: Participants with the following can be enrolled: Adequately resected non-melanoma skin cancer, curatively treated in situ disease, superficial cancer in the gastrointestinal tract curatively resected by endoscopic surgery, or any other solid tumors curatively treated with no evidence of recurrent disease for ≥3 years and requires no treatment.
  7. Has unresolved toxicities from previous anticancer treatment, defined as toxicities (other than alopecia) not yet resolved to National Cancer Institute (NCI-CTCAE) v5.0, Grade ≤1 or baseline. Note: Participants with chronic, stable Grade 2 toxicities (defined as no worsening for 1 month prior to enrollment and managed with SOC treatment) that the investigator deems related to previous anticancer treatment may be enrolled. Such toxicities may include the following:

    1. Chemotherapy-induced peripheral neuropathy
    2. Residual toxicities from prior immuno-oncology treatment:

    Grade 2 endocrinopathies (hypothyroidism, hyperthyroidism, adrenal insufficiency, hyperglycemia due to type 1 diabetes mellitus) with adequate therapy Grade 2 skin hypopigmentation (vitiligo)

  8. Has known to biological agents.
  9. Has a history of or active disease.

    Note: Participants with the following examples may be enrolled as an exception:

    1. Type I diabetes mellitus/hypothyroidism only requires hormone replacement.
    2. Skin disorders (such as vitiligo, psoriasis, or alopecia) not requiring systemic treatment.
  10. Has (HIV) infection. Participants must be tested for HIV viral load during the Screening Period if acceptable by local regulations or Institutional Review Boards/Independent Ethics Committees (IRBs/IECs).

    Note: For Part 2 only, the following participants will be eligible:

    1. Have ≥350 cells/mm3 at the time of screening.
    2. Have virologic suppression, defined as confirmed HIV RNA level below 50 or the lower limit of quantitation (below the limit of detection) at the time of screening and for at least 12 weeks before screening.
    3. Have no acquired immunodeficiency syndrome-defining opportunistic infections or conditions within the past 12 months.
    4. Are on stable antiretroviral therapy regimen, without changes in drugs or dose modification, for at least 4 weeks before trial entry (Day 1) and agree to continue antiretroviral therapy throughout the trial, as defined per institutional protocol.
  11. Has active or uncontrolled or C infection as defined per institutional guidelines.

Note: For Part 2 only, the following participants will be eligible:

  1. Hepatitis B surface antigen (HBsAg)-positive participants are eligible if they have received hepatitis B virus (HBV) antiviral therapy for at least 4 weeks and have undetectable HBV viral load prior to allocation (participants should remain on antiviral therapy throughout trial intervention and follow local guidelines for HBV antiviral therapy after completion of trial intervention).
  2. Have a history of infection and hepatitis C virus (HCV) viral load is below the level of detection in the absence of antiviral therapy during the previous 4 weeks.
  3. Have normal transaminase values, or, if liver metastases are present, abnormal transaminases with a result of AST/ALT \<3 × ULN, which are not attributable to HCV infection.
Terms in these criteria, in plain language(33)

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.

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.

Relapsed and refractory

Relapsed: the illness came back after treatment had worked. Refractory: it did not respond to treatment, or stopped responding while still on it.

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.

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.

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.

ALT and AST (liver enzymes)

Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.

Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.

ULN (upper limit of normal)

The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.

“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.

Bilirubin

A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.

Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.

Absolute neutrophil count (ANC)

The number of neutrophils, white blood cells that help fight infection, in a given amount of blood. Too few raises the risk of infection.

It is a count, not a percentage of the white cells. Limits are written in units that mean the same: ≥ 1.5 × 10⁹/L is ≥ 1,500 per mm³ (µL). Each lab has its own reference range.

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.

Hemoglobin (Hb)

The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).

Creatinine clearance (CrCl)

How quickly the kidneys clear creatinine, a waste product, from the blood. A study may estimate it from a blood test with age, weight and sex (often by the Cockcroft–Gault formula), or measure it using blood and urine collected over a set time. Given in mL/min; higher is better.

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.

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.

Washout period

A planned gap after a treatment, so that its effects can lessen before the study treatment or a study assessment. Ask the study team and the doctor who prescribed it before changing any medicine.

Leptomeningeal disease

Cancer that has spread to the leptomeninges, the thin layers covering the brain and spinal cord, and the fluid between them. It is not the same as brain metastases.

Criteria often treat it separately, and many studies leave it out even where treated brain metastases are allowed.

Brain metastases

Cancer deposits in the brain from a cancer that started elsewhere in the body (CNS metastases include the spinal cord).

Studies differ: some leave out any brain metastases, some accept ones treated and stable for some weeks. Check what this study allows.

Clinically significant

Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.

NYHA class (heart failure)

The New York Heart Association’s four classes of how much heart failure limits physical activity.

I
No limits: ordinary activity causes no undue tiredness or breathlessness.
II
Slight limits: comfortable at rest, ordinary activity causes symptoms.
III
Marked limits: comfortable at rest, less than ordinary activity causes symptoms.
IV
Symptoms even at rest; any activity makes them worse.

Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.

LVEF (left ventricular ejection fraction)

The share of blood the heart’s main pumping chamber (the left ventricle) pushes out with each beat, measured by an echocardiogram (heart ultrasound) or a MUGA scan. About 50–70% is normal.

QT and QTc

On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.

The study may name a correction formula and a limit in milliseconds, often around 450–480.

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.

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.

CTCAE grade

The US National Cancer Institute’s scale of how severe an adverse event is — any unwanted medical event during a study, such as a symptom, an illness or an abnormal test result, whether or not a treatment caused it. Whether it did is judged separately.

1
Mild.
2
Moderate.
3
Severe.
4
Life-threatening.
5
Death due to the event.

“Side effects of earlier treatment resolved to grade 1 or less” means they have settled to mild or gone.

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.

Autoimmune disease

A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.

Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.

HIV

The human immunodeficiency virus, which weakens the immune system.

Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.

CD4 count

The number of CD4 cells, a type of white blood cell, in a given amount of blood. It is used to follow how well the immune system is doing in HIV.

Hepatitis B tests

Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.

Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.

Hepatitis C tests

Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.

After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.

05

Study design

Phase
Phase 1
Primary purpose
Treatment
Allocation
Not applicable
Intervention model
Sequential assignment
Masking
None (open label)
Enrollment
150 participants (estimated)

Study arms

  • Experimental
    Part 1: Dose Escalation DS-2243a

    Participants will receive DS-2243a at escalating doses. The recommended dose for expansion (RDE) will be calculated using data collected from this population.

    Drug: DS-2243a

  • Experimental
    Part 2: Dose Expansion SS/MRCLS

    Participants with synovial sarcoma or myxoid/round cell liposarcoma will receive DS-2243a at the recommended dose for expansion (RDE)

    Drug: DS-2243a

  • Experimental
    Part 2: Dose Expansion Sq-NSCLC

    Participants with squamous cell carcinoma-non-small cell lung cancer will receive DS-2243a at the recommended dose for expansion (RDE)

    Drug: DS-2243a

  • Experimental
    Part 2: Dose Expansion UC

    Participants with urothelial carcinoma will receive DS-2243a at the recommended dose for expansion (RDE)

    Drug: DS-2243a

  • Experimental
    Part 2: Dose Expansion Ad-NSCLC

    Participants with adenocarcinoma-non-small cell lung cancer will receive DS-2243a at the recommended dose for expansion (RDE)

    Drug: DS-2243a

Interventions

  • DrugDS-2243a

    Escalation Part: DS-2243a will be administered at escalating doses to determine the RDE Expansion Part: DS-2243a will be administered at RDE

06

What researchers measure

Primary outcomes

  1. Part 1: Number of participants with Dose-Limiting Toxicities at each dose level of DS-2243a

    Time frame: Up to 18 months

  2. Part 2: Number of participants with Treatment-Emergent Adverse Events

    Descriptive statistics of treatment-emergent adverse events (TEAEs)

    Time frame: Up to 3 years

  3. Part 2: Objective Response Rate

    Objective Response Rate (ORR) as assessed by the investigator according to RECIST v1.1.

    Time frame: From day of first dose up to 3 years

Secondary outcomes

  1. Part 1: Objective Response Rate

    ORR as assessed by the investigator according to RECIST v1.1.

    Time frame: From day of first dose up to 3 years

  2. Disease Control Rate

    Disease Control Rate (DCR) as assessed by the investigator according to RECIST v1.1.

    Time frame: From day of first dose up to 4 years.

  3. Progression-Free Survival (PFS)

    Progression-Free Survival (PFS) as assessed by the investigator according to RECIST v1.1.

    Time frame: From day of first dose up to 4 years

  4. Overall Survival

    Time frame: From day of first dose up to 4 years

  5. Drug Plasma Concentration

    Time frame: Days 1, 2, and 3 during step-up dosing; Days 1, 2, 3, 5, 8, and 15 of Cycles 1 and 3; Day 1 of Cycle 2; and Day 1 of Cycle 4 and each subsequent cycle. A cycle may be up to 36 days.

07

Study locations

7 of 7 sites recruiting
08

References and documents

Individual participant data

Plan to share: Yes — De-identified individual participant data (IPD) on completed studies and applicable supporting clinical trial documents may be available upon request at https://vivli.org/. In cases where clinical trial data and supporting documents are provided pursuant to our company policies and procedures, Daiichi Sankyo will continue to protect the privacy of our clinical trial participants. Details on data sharing criteria and the procedure for requesting access can be found at this web address: https://vivli.org/ourmember/daiichi-sankyo/

Supporting information: Study protocol, Statistical analysis plan, Informed consent form

Time frame: Completed studies that has reached a global end or completion with all data set collected and analyzed, and for which the medicine and indication have received European Union (EU) and United States (US), and/or Japan (JP) marketing approval on or after 01 January 2014 or by the US or EU or JP Health Authorities when regulatory submissions in all regions are not planned and after the primary study results have been accepted for publication.

Access criteria: Access Criteria: Formal request from qualified scientific and medical researchers on IPD and clinical study documents on completed clinical trials supporting products submitted and licensed in the United States, the European Union and/or Japan from 01 January 2014 and beyond for the purpose of conducting legitimate research. This must be consistent with the principle of safeguarding study participants' privacy and consistent with provision of informed consent.

Data sharing details ↗ · vivli.org

No publications or documents are linked to this record.

09

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Sep 4, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT06644755
Lead sponsor
Daiichi Sankyo
Responsible party
Sponsor
First posted
Oct 16, 2024
Start date
Nov 14, 2024
Primary completion
Nov 30, 2028 (estimated)
Completion
Nov 30, 2028 (estimated)
Last update
Sep 4, 2026

Study contacts

Contact for Trial Information
Contact
CTRinfo_us@daiichisankyo.com
908-992-6400

Oversight

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

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