What is the mechanism of action of this treatment?

CDK4/6 inhibitors, such as Palbociclib, play a crucial role in the treatment of hormone receptor-positive, HER2-negative breast cancer by targeting cyclin-dependent kinases 4 and 6. These kinases are essential for cell cycle progression, and their inhibition prevents cancer cells from proliferating. This mechanism is particularly important for breast cancer patients as it offers a targeted approach to slow down tumor growth and improve progression-free survival. Understanding the hormone receptor and HER2 status of the tumor is vital for selecting the most effective treatment, ensuring personalized and effective cancer care.

What side effects are associated with this type of intervention?

Common treatments for breast cancer, particularly those similar to Palbociclib (a CDK4/6 inhibitor), often have side effects such as neutropenia, leukopenia, fatigue, nausea, alopecia, and diarrhea. Endocrine therapies, frequently used in combination with CDK4/6 inhibitors, can cause hot flashes, joint pain, osteoporosis, and cardiovascular risks. Chemotherapy, another prevalent treatment, is associated with hair loss, nausea, vomiting, fatigue, and increased infection risk due to bone marrow suppression.

What prior FDA approvals exist?

The FDA has approved several CDK4/6 inhibitors for the treatment of hormone receptor-positive, HER2-negative breast cancer. Palbociclib (Ibrance) was the first CDK4/6 inhibitor approved in combination with letrozole for postmenopausal women with ER+/HER2- advanced breast cancer. Following this, ribociclib (Kisqali) and abemaciclib (Verzenio) were also approved for similar indications. These drugs work by inhibiting cyclin-dependent kinases 4 and 6, which are crucial for cell cycle progression, thereby helping to control cancer cell proliferation.

What other types of research exist?

Promising alternatives to Palbociclib for breast cancer patients include other CDK4/6 inhibitors such as Ribociclib and Abemaciclib. Additionally, novel therapies like selective estrogen receptor degraders (SERDs) such as Elacestrant, and PI3K inhibitors like Alpelisib, are also showing potential in clinical trials.

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Endocrine Therapy

Palbociclib + Endocrine Therapy for Breast Cancer (PALLAS Trial)

Phase 3

Waitlist Available

Led By Suzanne George, MD

Research Sponsored by Alliance Foundation Trials, LLC.

Eligibility Criteria Checklist

Specific guidelines that determine who can or cannot participate in a clinical trial

Must have

Patients must have sufficient resolution of any surgical side effects (no active wound healing complications).

Serum creatinine below the upper limit of the institutional normal range (ULN) or creatinine clearance ≥ 60 mL/min/1.73 m2 for patients with serum creatinine levels above institutional ULN.

Must not have

Patients with Stage I or IV breast cancer are not eligible.

Patients with a history of any malignancy are ineligible.

Timeline

Screening 3 weeks

Treatment Varies

Follow Up 4 years

Awards & highlights

No Placebo-Only Group

Pivotal Trial

Summary

This trial is testing whether adding the drug palbociclib to standard hormone therapy can improve treatment for patients with a specific type of early breast cancer. The targeted patients have hormone receptor-positive and HER2-negative breast cancer. Palbociclib works by blocking proteins that help cancer cells grow, potentially making the hormone therapy more effective.

Who is the study for?

This trial is for adults over 18 with HR+/HER2- early breast cancer (Stage II or III), who have had surgery, can take oral meds, and are on or starting hormone treatment. They must not be pregnant, have normal organ function tests, no history of other cancers, and no severe illnesses that could affect participation.

What is being tested?

The study is testing if adding palbociclib to standard endocrine therapy after breast cancer surgery improves patient outcomes compared to endocrine therapy alone. It's a Phase III trial where patients are randomly assigned to two groups in an open-label setting.

What are the potential side effects?

Palbociclib may cause low white blood cell counts which can lead to infection risk, fatigue, nausea, hair thinning or loss, nosebleeds and other bleeding issues. Side effects vary from person to person.

Eligibility Criteria

Inclusion Criteria

You may be eligible if you check “Yes” for the criteria below

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I have healed from surgery without any ongoing wound issues.

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My kidney function, measured by creatinine levels, is within the normal range.

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I have had surgery to remove my breast cancer.

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I am starting or already on hormone therapy after cancer surgery.

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I have Stage II or III early invasive breast cancer.

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I can swallow and keep down pills.

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I have Stage II or III early invasive breast cancer.

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My breast cancer is ER+ or PR+, and not HER2+.

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I am fully active or can carry out light work.

Exclusion Criteria

You may be eligible for the trial if you check “No” for criteria below:

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My breast cancer is not Stage I or IV.

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I have never had any type of cancer before.

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I am currently on antiretroviral therapy.

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I am not taking strong medication that affects liver enzymes.

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I had hormone therapy for cancer within the last 5 years.

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I have a history of serious liver disease.

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I have been treated with a CDK inhibitor before.

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I am allergic to medications similar to palbociclib.

Timeline

Screening ~ 3 weeks3 visits

Treatment ~ Varies

Follow Up ~ 4 years

Screening ~ 3 weeks

Treatment ~ Varies

Follow Up ~4 years

This trial's timeline: 3 weeks for screening, Varies for treatment, and 4 years for reporting.

Treatment Details

Study Objectives

Study objectives can provide a clearer picture of what you can expect from a treatment.

Primary study objectives

Invasive Disease Free Survival (iDFS)

Secondary study objectives

Distant Recurrence-free Survival (DRFS)

Invasive Disease Free Survival (iDFS) Excluding Second Primary Invasive Cancers of Non-breast Origin.

Locoregional Recurrences-free Survival (LRRFS)

+1 more

Awards & Highlights

No Placebo-Only Group

All patients enrolled in this study will receive some form of active treatment.

Pivotal Trial

The final step before approval, pivotal trials feature drugs that have already shown basic safety & efficacy.

Trial Design

2Treatment groups

Experimental Treatment

Group I: Arm BExperimental Treatment1 Intervention

Standard adjuvant endocrine therapy for a duration of at least 5 years.

Group II: Arm AExperimental Treatment2 Interventions

Palbociclib at a dose of 125 mg orally once daily, Day 1 to Day 21 followed by 7 days off treatment in a 28-day cycle for a total duration of 2 years, in addition to standard adjuvant endocrine therapy for a duration of at least 5 years.

Treatment

First Studied

Drug Approval Stage

How many patients have taken this drug

Palbociclib

2017

Completed Phase 3

~3880

0 / 17Eligibility criteria met

Research Highlights

Information in this section is not a recommendation. We encourage patients to speak with their healthcare team when evaluating any treatment decision.

Mechanism Of Action

Side Effect Profile

Prior Approvals

Other Research

CDK4/6 inhibitors, such as Palbociclib, play a crucial role in the treatment of hormone receptor-positive, HER2-negative breast cancer by targeting cyclin-dependent kinases 4 and 6. These kinases are essential for cell cycle progression, and their inhibition prevents cancer cells from proliferating. This mechanism is particularly important for breast cancer patients as it offers a targeted approach to slow down tumor growth and improve progression-free survival. Understanding the hormone receptor and HER2 status of the tumor is vital for selecting the most effective treatment, ensuring personalized and effective cancer care.