MT-4561 for Cancer

Recruiting at 5 trial locations

Overseen By Clinical Trials Information Desk, to prevent miscommunication,

Age: 18+

Sex: Any

Trial Phase: Phase 1 & 2

Sponsor: Mitsubishi Tanabe Pharma America Inc.

Must not be taking: QT prolonging drugs

Disqualifiers: Active brain metastases, unresolved toxicity, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: Unknown

27 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial tests a new drug, MT-4561, for individuals with advanced solid tumors, such as lung, breast, or prostate cancer, who have not succeeded with other treatments. The trial aims to determine the safety and efficacy of MT-4561. In the first phase, participants receive the drug through an IV once a week to establish the optimal dose. It suits those with no remaining treatment options and a confirmed diagnosis of specific cancers. As a Phase 1 trial, participants will be among the first to receive MT-4561, aiding researchers in understanding how the treatment works in people.

Will I have to stop taking my current medications?

The trial requires that you stop taking any prior systemic anticancer therapy at least 4 weeks before starting the study drug, or 5 half-lives of the drug, whichever is shorter. Additionally, you must not have taken drugs that can prolong the QT interval within 14 days or 5 half-lives before starting the study drug.

Is there any evidence suggesting that MT-4561 is likely to be safe for humans?

Studies have shown that MT-4561 is generally safe for humans. Common side effects include tiredness and febrile neutropenia, which involves a fever and a low white blood cell count. However, MT-4561 has a manageable safety profile, meaning that while some side effects can occur, they are not severe for most people. Researchers are conducting more studies to confirm these findings and determine the best treatment dose. ^{1 2 3 4 5}

Why do researchers think this study treatment might be promising?

Unlike the standard cancer treatments, which often include chemotherapy, radiation, and surgery, MT-4561 offers a novel approach by utilizing a unique mechanism of action. This drug is administered through an intravenous infusion once a week and targets cancer cells differently from traditional therapies. Researchers are particularly excited about MT-4561 because it could potentially slow disease progression with fewer side effects, providing a more targeted and possibly more effective treatment option for patients with cancer.

What evidence suggests that MT-4561 might be an effective treatment for cancer?

Research has shown that MT-4561 is a new treatment that breaks down certain proteins linked to cancer growth. In lab studies, this treatment consistently stopped tumor growth in both animals and patient-derived cells. These early results suggest that MT-4561 might slow or halt the growth of solid tumors. Although more information from human studies is needed, these promising findings support the potential effectiveness of MT-4561 in treating advanced cancers. Participants in this trial will receive MT-4561 through intravenous infusion once a week in a 28-day cycle, until disease progression or discontinuation criteria are met. ^{1 4 5 6 7}

Who Is on the Research Team?

Head of Medical Science

Principal Investigator

Mitsubishi Tanabe Pharma America Inc.

Are You a Good Fit for This Trial?

This trial is for patients with various advanced solid tumors who are seeking new treatment options. Participants must meet specific health criteria, which will be detailed in the study's inclusion and exclusion sections.

Inclusion Criteria

Life expectancy of at least 3 months

I have at least one tumor that can be measured and biopsied.

My bone marrow is working well.

Exclusion Criteria

I have no lasting side effects from cancer treatment, except for hair loss.

QT interval corrected for heart rate using Fridericia's correction (QTcF) > 470 msec at screening

I have active brain or spinal cord cancer spread.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Dose-escalation

Participants receive intravenous infusion of MT-4561 once every week in a 28-day cycle to evaluate safety, tolerability, PK, and pharmacodynamics and determine the Maximum Tolerated Dose (MTD)

28 days per cycle

Weekly visits for infusion

Dose-optimization

Further evaluation of MT-4561 dosing based on results from Part 1

Not specified

Drug-Drug Interaction

Evaluation of the effect of MT-4561 on the pharmacokinetics of oral Midazolam

Not specified

Follow-up

Participants are monitored for safety and effectiveness after treatment

30 days after last dose

What Are the Treatments Tested in This Trial?

Interventions

• MT-4561

Trial Overview MT-4561, a new potential cancer therapy, is being tested across three parts: assessing safety and finding the highest dose patients can tolerate (Part 1), optimizing dosage (Part 2), and studying drug interactions (Part 3).

How Is the Trial Designed?

Group I: Part 1 (Dose-escalation) Experimental Treatment 1 Intervention

Intravenous (IV) infusion of MT-4561 once every week in 28-day cycle, until disease progression or discontinuation criteria are met.

Who Is Running the Clinical Trial?

Mitsubishi Tanabe Pharma America Inc.

Lead Sponsor

Trials

27

Recruited

3,300+

Published Research Related to This Trial

Adjuvant therapy with PD-1/PD-L1 inhibitors significantly improves overall survival (OS) and disease-free survival (DFS) in cancer patients, based on a meta-analysis of six randomized controlled trials involving 4,436 participants.

While these treatments offer substantial survival benefits, they are also associated with a higher risk of severe treatment-related adverse events (≥ grade 3), indicating a need for careful monitoring during therapy.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Efficacy and safety of adjuvant therapy with PD‑1/PD‑L1 inhibitors in cancer. Mo, DC., Liang, ZY., Chen, L., et al.[2022]

Neoadjuvant anti-PD-1/PD-L1 therapy showed promising efficacy, with a complete response rate of 56.9% in triple-negative breast cancer and a major response rate of 47.1% in lung cancer, based on a meta-analysis of 20 studies involving 828 patients.

The therapy was generally safe, with fatigue being the most common adverse event (27.2%), while febrile neutropenia was the most frequent high-grade adverse event (8.4%).

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Clinical benefit of neoadjuvant anti-PD-1/PD-L1 utilization among different tumors. Li, Z., Wu, X., Zhao, Y., et al.[2021]

In a meta-analysis of 4413 patients from 8 randomized controlled trials, PD-1/PD-L1 inhibitors showed a significantly lower risk of all-grade adverse events (66.20% vs. 86.08%) and high-grade adverse events (14.26% vs. 43.53%) compared to chemotherapy, indicating a better safety profile.

While PD-1/PD-L1 inhibitors are generally safer, they are associated with a unique set of immune-related adverse events (irAEs) that can be severe, such as pneumonitis and thyroid dysfunction, which clinicians need to monitor closely to manage patient quality of life.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Safety and tolerability of PD-1/PD-L1 inhibitors in the treatment of non-small cell lung cancer: a meta-analysis of randomized controlled trials. Luo, W., Wang, Z., Tian, P., et al.[2021]

Citations

1. mt-pharma-america.com mt-pharma-america.com/media/press-releases/2025/mitsubishi-tanabe-pharma-america-advances-oncology-pipeline-first-patient-dosed-in-mt-4561-trial-for-advanced-solid-tumors

First Patient Dosed in MT-4561 Trial for Advanced Solid ... MT-4561 is a novel BRD4 degrader that exerts continuous anti-tumor effects in various cancer xenograft models and patient derived cells.

2. clinicaltrials.gov clinicaltrials.gov/study/NCT06943521

NCT06943521 | A Study of MT-4561 in Patients With ... This is a First In Human (FIH), multicenter, open-label, Phase I/II study to evaluate safety, tolerability, Pharmacokinetics (PK), pharmacodynamics, ...

3. mdanderson.org mdanderson.org/patients-family/diagnosis-treatment/clinical-trials/clinical-trials-index/clinical-trials-detail.ID2025-0133.html

A phase I/II, dose-escalation and dose-optimization study ... This study will be conducted in 3 parts. Part 1 is aimed at evaluating safety, tolerability, PK and pharmacodynamics of MT-4561 and determining the Maximum ...

4. mt-pharma.co.jp mt-pharma.co.jp/e/news/assets/pdf/e_MTPC250613.pdf

Initiation of Phase 1/2 clinical trial of MT-4561 for Advanced ... MT-4561 is a novel BRD4 degrader that exerts continuous anti-tumor effects in various cancer xenograft models and patient derived cells.

5. bcan.org bcan.org/clinicaltrials/mt-4561-in-patients-with-various-advanced-solid-tumors/

MT-4561 in Patients With Various Advanced Solid Tumors This is a First In Human (FIH), multicenter, open-label, Phase I/II study to evaluate safety, tolerability, Pharmacokinetics (PK), pharmacodynamics, and ...

6. withpower.com withpower.com/trial/phase-2-stomach-neoplasms-3-2025-7461d

MT-4561 for Cancer · Recruiting Participants for Phase ... Common side effects include fatigue and febrile neutropenia (a condition with fever and low white blood cells), but the overall safety profile is considered ...

7. trials.braintumor.org trials.braintumor.org/trials/NCT06943521

A Study of MT-4561 in Patients With Various Advanced Solid ... This study will be conducted in 3 parts. Part 1 is aimed at evaluating safety, tolerability, PK and pharmacodynamics of MT-4561 and determining the Maximum ...