Imlunestrant + Abemaciclib for Breast Cancer

Overseen By Ruth Gonzalez

Age: 18+

Sex: Any

Trial Phase: Phase 2

Sponsor: Jonsson Comprehensive Cancer Center

Must be taking: Endocrine therapy

Must not be taking: Herbal supplements

Disqualifiers: Metastatic disease, Uncontrolled illness, others

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

Prior Safety Data This treatment has passed at least one previous human trial

Breakthrough Therapy This drug has been fast-tracked for approval by the FDA given its high promise

Compensation: Varies

Number of Visits: 1

Duration: 12 cycles (28 days each)

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial explores the effectiveness of combining imlunestrant and abemaciclib in treating a specific type of breast cancer, where small amounts of tumor cells remain in the blood after initial treatment. Imlunestrant reduces estrogen, which can fuel cancer growth, while abemaciclib targets enzymes necessary for tumor growth. The trial includes individuals with estrogen receptor-positive breast cancer who show no signs of cancer spreading and are currently on hormone treatment. Participants must have been on hormone therapy for at least two years and have detectable cancer cells in their blood. As a Phase 2 trial, this research measures the treatment's effectiveness in an initial, smaller group, allowing participants to contribute to significant advancements in breast cancer therapy.

Do I have to stop taking my current medications for the trial?

The trial requires participants to continue their current adjuvant endocrine therapy, such as tamoxifen or aromatase inhibitors, for at least 2 years. However, herbal products and supplements are generally not allowed, and any other anti-cancer investigational agents are prohibited.

Is there any evidence suggesting that this trial's treatments are likely to be safe?

Research has shown that both imlunestrant and abemaciclib are generally safe for patients with estrogen receptor-positive breast cancer. Studies have found that imlunestrant, whether used alone or with abemaciclib, has a manageable safety profile, meaning most patients do not experience severe side effects.

Safety data from previous studies also suggest that this combination is well-tolerated, with side effects, if any, usually not serious. This makes the treatment an attractive option for those with minimal remaining disease after initial therapy.

While this information is encouraging, it is important to remember that every treatment can have some risks. Joining a clinical trial may provide access to new therapies and close monitoring by healthcare professionals. ^{1 2 3 4 5}

Why are researchers excited about this trial's treatments?

Researchers are excited about the combination of Imlunestrant and Abemaciclib for breast cancer because it represents a fresh approach to treatment. Unlike standard therapies that primarily target hormone receptors or cancer cell division separately, this duo combines a selective estrogen receptor degrader (Imlunestrant) with a CDK4/6 inhibitor (Abemaciclib). This dual-action strategy could potentially offer more robust control of cancer growth by simultaneously blocking estrogen receptor signaling and disrupting cancer cell proliferation. This innovative combination may provide a more comprehensive attack on cancer cells, possibly leading to better outcomes for patients.

What evidence suggests that imlunestrant and abemaciclib might be effective treatments for ER+ breast cancer?

Studies have shown that the combination of imlunestrant and abemaciclib, which participants in this trial will receive, can help treat estrogen receptor-positive (ER+) breast cancer. This combination improved progression-free survival, allowing patients to live longer without their cancer worsening. Imlunestrant alone has already outperformed standard treatments for some breast cancers. When combined with abemaciclib, these drugs consistently benefited patients, even those who had previously tried similar treatments. This suggests that imlunestrant and abemaciclib could effectively manage ER+ breast cancer. ^{1 3 6 7 8}

Who Is on the Research Team?

Marla Lipsyc-Sharf

Principal Investigator

UCLA / Jonsson Comprehensive Cancer Center

Are You a Good Fit for This Trial?

This trial is for patients with estrogen receptor positive (ER+) breast cancer who still have tumor cells in their blood after initial treatment. Participants should be those whose cancer growth may be influenced by estrogen levels.

Inclusion Criteria

I am 18 years old or older.

Detectable ctDNA in a CLIA-certified lab within the past six months with no clinical or radiographic evidence of recurrence

I may have had radiation after surgery with limited side effects.

Exclusion Criteria

Participants receiving any other anti-cancer investigational agents

I am HIV-positive and not taking antiretroviral therapy.

Personal history of specific cardiovascular conditions

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive abemaciclib orally twice daily and imlunestrant once daily on days 1-28 of each cycle. Cycles repeat every 28 days for up to 12 cycles.

12 cycles (28 days each)

Monthly visits for each cycle

Follow-up

Participants are monitored for safety and effectiveness after treatment, with follow-up at 30 days and then every 4 months for 1 year.

1 year

1 visit at 30 days, then every 4 months

What Are the Treatments Tested in This Trial?

Interventions

• Abemaciclib
• Imlunestrant

Trial Overview The MIRI Trial is testing the effectiveness of Imlunestrant and Abemaciclib on ER+ breast cancer with minimal residual disease. The study aims to see if these drugs can stop or slow down tumor cell growth by affecting estrogen production and blocking enzymes needed for cell growth.

How Is the Trial Designed?

Group I: Treatment (abemaciclib, imlunestrant) Experimental Treatment 5 Interventions

Patients receive abemaciclib PO BID and imlunestrant PO QD on days 1-28 of each cycle. Cycles repeat every 28 days for up to 12 cycles in the absence of disease progression or unacceptable toxicity. Additionally, patients undergo blood sample collection throughout the study. Patients may also undergo radiological scans per the discretion of the treating physician throughout the study.

Who Is Running the Clinical Trial?

Jonsson Comprehensive Cancer Center

Lead Sponsor

Trials

373

Recruited

35,200+

Citations

1. pubmed.ncbi.nlm.nih.gov pubmed.ncbi.nlm.nih.gov/39660834/

Imlunestrant with or without Abemaciclib in Advanced ... The estimated restricted mean survival time at 19.4 months was 7.9 months (95% confidence interval [CI], 6.8 to 9.1) with imlunestrant and 5.4 ...

2. ascopubs.org ascopubs.org/doi/10.1200/JCO.2025.43.16_suppl.1060

Safety analyses from the phase III EMBER-3 trial. Imlunestrant, as monotherapy or in combination with abemaciclib, provides a safe, tolerable, all-oral targeted therapy option for patients with ER+, HER2- ABC.

3. acsjournals.onlinelibrary.wiley.com acsjournals.onlinelibrary.wiley.com/doi/full/10.1002/cncr.35913

Imlunestrant significantly improves PFS for patients with ... Imlunestrant conferred significantly longer progression-free survival (PFS) than standard therapy to patients with advanced breast cancer with ESR1 mutations.

4. onclive.com onclive.com/view/imlunestrant-plus-abemaciclib-provides-consistent-benefit-across-key-subsets-of-er-advanced-breast-cancer

Imlunestrant Plus Abemaciclib Provides Consistent Benefit ... Imlunestrant plus abemaciclib improved PFS in ER-positive, HER2-negative advanced breast cancer, regardless of biomarker status or prior CDK4/6 ...

5. investor.lilly.com investor.lilly.com/news-releases/news-release-details/lillys-imlunestrant-oral-serd-significantly-improved-progression

Lilly's Imlunestrant, an Oral SERD, Significantly Improved ... Imlunestrant significantly reduced the risk of progression or death by 38% compared to standard endocrine therapy (ET) in patients with ESR1 mutations.

6. pubmed.ncbi.nlm.nih.gov pubmed.ncbi.nlm.nih.gov/39241211/

Imlunestrant, an Oral Selective Estrogen Receptor ... - PubMed Conclusion: Imlunestrant, as monotherapy or in combination with targeted therapy, had a manageable safety profile with evidence of preliminary ...

7. onclive.com onclive.com/view/imulnestrant-plus-abemaciclib-extends-pfs-over-soc-in-er-her2-advanced-breast-cancer

Imulnestrant Plus Abemaciclib Extends PFS Over SOC in ... Imlunestrant plus abemaciclib significantly prolonged PFS in ER-positive, HER2-negative advanced breast cancer, regardless of ESR1 mutation ...

8. asco.org asco.org/abstracts-presentations/ABSTRACT492010

Safety analyses from the phase III EMBER-3 trial. Imlunestrant, as monotherapy or in combination with abemaciclib, provides a safe, tolerable, all-oral targeted therapy option for patients with ER+, HER2- ABC.