RGT-419B + Hormonal Therapy for Breast Cancer

Recruiting in Palo Alto (17 mi)

+4 other locations

Age: 18+

Sex: Any

Travel: May Be Covered

Time Reimbursement: Varies

Trial Phase: Phase 1

Recruiting

Sponsor: Regor Pharmaceuticals Inc.

Must be taking: Hormonal therapy

Disqualifiers: Visceral metastases, Pregnancy, others

No Placebo Group

Trial Summary

What is the purpose of this trial?

This trial is testing a new oral drug, RGT-419B, for patients with advanced breast cancer who haven't responded to other treatments. The study aims to see if the drug can safely stop cancer cell growth.

Will I have to stop taking my current medications?

The trial does not specify if you need to stop your current medications, but it mentions that major treatments like chemotherapy or radiation should not have been received within 14-28 days before starting the trial. It's best to discuss your current medications with the trial team.

What data supports the effectiveness of the drug RGT-419B when used with hormonal therapy for breast cancer?

The research highlights that combining hormonal therapy with other agents, like CDK4/6 inhibitors, has improved survival rates in breast cancer patients. This suggests that combining RGT-419B with hormonal therapy might also enhance treatment effectiveness by potentially overcoming resistance to endocrine therapy. ^{1 2 3 4 5}

What safety data exists for RGT-419B + Hormonal Therapy for Breast Cancer?

The safety of targeted therapies like CDK4/6 inhibitors, which are often combined with hormone therapy for breast cancer, is generally manageable but can include side effects like neutropenia (low white blood cell count) and stomatitis (mouth sores). These side effects require careful management, often involving dose adjustments or additional treatments. ^{6 7 8 9 10}

How does the drug RGT-419B + Hormonal Therapy differ from other breast cancer treatments?

RGT-419B + Hormonal Therapy is unique because it combines a novel drug, RGT-419B, with hormonal therapy, potentially offering a new mechanism of action or enhanced effectiveness compared to existing treatments like tamoxifen or aminoglutethimide alone. This combination may provide a more comprehensive approach by targeting different pathways involved in breast cancer progression. ^{11 12 13 14 15}

Research Team

Eligibility Criteria

This trial is for adults with HR+, HER2- advanced or metastatic breast cancer who've had no more than one prior chemotherapy in this setting and less than three lines of CDK4/6i therapy. Participants must have an ECOG Performance Status of 0 to 1, indicating they are fully active or restricted in physically strenuous activity but ambulatory.

Inclusion Criteria

My tumor is HR positive, HER2 negative, and can be measured.

I've had only one chemotherapy for advanced breast cancer, tolerated CDK4/6 inhibitors well, can take RT-419B, and recovered from past therapy side effects.

I have advanced breast cancer, tried <3 CDK4/6i therapies, and no more than 1 chemotherapy.

Exclusion Criteria

My cancer has spread to my organs, causing severe problems.

I haven't had major surgery or cancer treatment in the last 14 days.

I have not had radiation to more than a quarter of my bone marrow and my organs are functioning well.

Trial Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive RGT-419B as monotherapy or in combination with Hormonal Therapy to evaluate safety, tolerability, and pharmacokinetics

4 weeks (1 cycle)

Multiple visits for dose administration and monitoring

Follow-up

Participants are monitored for safety, tolerability, and efficacy through study completion

up to 1 year

Treatment Details

Interventions

• RGT-419B (Small Molecule Inhibitor)

Trial Overview The study tests RGT-419B, a new oral medication, alone or combined with hormonal therapy. It's a phase I trial focusing on safety, how the body processes the drug (pharmacokinetics), and its initial effectiveness against certain types of breast cancer that progressed after previous treatments.

Participant Groups

Group I: Arm B Experimental Treatment 1 Intervention

RGT-419B in combination with Hormonal Therapy

Group II: Arm A Experimental Treatment 1 Intervention

RGT-419B given alone as monotherapy

Find a Clinic Near You

Research Locations Nearby Select from list below to view details:

Hem-Onc Associates of the Treasure Coast Port Saint Lucie, FL

Emory University Atlanta, GA

Massachusetts General Hospital Boston, MA

New York Cancer and Blood Specialists Port Jefferson Station, NY

More Trial Locations

Who Is Running the Clinical Trial?

Regor Pharmaceuticals Inc.

Lead Sponsor

Trials

6

Patients Recruited

440+

Findings from Research

Endocrine therapy, particularly the use of tamoxifen and aromatase inhibitors, has significantly improved survival rates in estrogen receptor positive breast cancer, with recent studies suggesting that extending tamoxifen treatment from 5 to 10 years may be beneficial.

The development of resistance to endocrine therapy is a major challenge, but combining treatments like the mTOR inhibitor everolimus with endocrine therapy has shown promise in redefining treatment strategies for metastatic breast cancer.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Breast cancer: current and future endocrine therapies. Palmieri, C., Patten, DK., Januszewski, A., et al.[2018]

Ribociclib combined with fulvestrant significantly improves progression-free survival (PFS) and overall survival (OS) in postmenopausal women with hormone receptor-positive, HER2-negative advanced breast cancer, particularly in those with limited prior treatment.

The safety profile of ribociclib is manageable, with myelosuppression being a common side effect, while other toxicities like hepatobiliary issues and QTc prolongation occur at low rates, indicating it can be a viable treatment option in clinical practice.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Ribociclib plus fulvestrant in the treatment of breast cancer. Neven, P., Sonke, GS., Jerusalem, G.[2021]

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Overcoming endocrine resistance in metastatic hormone receptor-positive breast cancer. D'Souza, A., Spicer, D., Lu, J.[2019]

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Update on endocrine therapy for breast cancer. Buzdar, AU., Hortobagyi, G.[2006]

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Endocrine therapy in post-menopausal women with metastatic breast cancer: From literature and guidelines to clinical practice. Sini, V., Cinieri, S., Conte, P., et al.[2018]

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Molecularly targeted therapy and immunotherapy for hormone receptor‑positive/human epidermal growth factor receptor 2‑negative advanced breast cancer (Review). Song, Y., He, L., Wang, Y., et al.[2021]

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Improving Response to Hormone Therapy in Breast Cancer: New Targets, New Therapeutic Options. Rugo, HS., Vidula, N., Ma, C.[2022]

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Management of toxicities associated with targeted therapies for HR-positive metastatic breast cancer: a multidisciplinary approach is the key to success. Cazzaniga, ME., Danesi, R., Girmenia, C., et al.[2020]

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Survival outcomes after neoadjuvant letrozole and palbociclib versus third generation chemotherapy for patients with high-risk oestrogen receptor-positive HER2-negative breast cancer. Delaloge, S., Dureau, S., D'Hondt, V., et al.[2022]

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Abiraterone shows alternate activity in models of endocrine resistant and sensitive disease. Simigdala, N., Pancholi, S., Ribas, R., et al.[2022]

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Treatment of advanced breast cancer with aminoglutethimide--response after previous tamoxifen treatment. Bezwoda, WR., Derman, DP., Browde, S., et al.[2014]

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[Hormone therapy of breast cancer in the metastatic phase in menopausal women]. Namer, M.[2016]

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The influence of aminoglutethimide and its analogue rogletimide on peripheral aromatisation in breast cancer. MacNeill, FA., Jones, AL., Jacobs, S., et al.[2019]

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[Experimental multihormone therapy on human breast carcinomas grown in nude mice]. Fukutomi, T.[2013]

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Response to aminoglutethimide after tamoxifen therapy in advanced breast cancer. Allison, RW., Furnival, CM., Lee, JF., et al.[2021]

References

1. Ireland pubmed.ncbi.nlm.nih.gov

Breast cancer: current and future endocrine therapies. [2018]

2. England pubmed.ncbi.nlm.nih.gov

Ribociclib plus fulvestrant in the treatment of breast cancer. [2021]

3. England pubmed.ncbi.nlm.nih.gov

Overcoming endocrine resistance in metastatic hormone receptor-positive breast cancer. [2019]

4. United States pubmed.ncbi.nlm.nih.gov

Update on endocrine therapy for breast cancer. [2006]

5. Netherlands pubmed.ncbi.nlm.nih.gov

Endocrine therapy in post-menopausal women with metastatic breast cancer: From literature and guidelines to clinical practice. [2018]

6. Greece pubmed.ncbi.nlm.nih.gov

Molecularly targeted therapy and immunotherapy for hormone receptor‑positive/human epidermal growth factor receptor 2‑negative advanced breast cancer (Review). [2021]

7. United States pubmed.ncbi.nlm.nih.gov

Improving Response to Hormone Therapy in Breast Cancer: New Targets, New Therapeutic Options. [2022]

8. Netherlands pubmed.ncbi.nlm.nih.gov

Management of toxicities associated with targeted therapies for HR-positive metastatic breast cancer: a multidisciplinary approach is the key to success. [2020]

9. England pubmed.ncbi.nlm.nih.gov

Survival outcomes after neoadjuvant letrozole and palbociclib versus third generation chemotherapy for patients with high-risk oestrogen receptor-positive HER2-negative breast cancer. [2022]

10. England pubmed.ncbi.nlm.nih.gov

Abiraterone shows alternate activity in models of endocrine resistant and sensitive disease. [2022]

11. South Africa pubmed.ncbi.nlm.nih.gov

Treatment of advanced breast cancer with aminoglutethimide--response after previous tamoxifen treatment. [2014]

12. France pubmed.ncbi.nlm.nih.gov

[Hormone therapy of breast cancer in the metastatic phase in menopausal women]. [2016]

13. England pubmed.ncbi.nlm.nih.gov

The influence of aminoglutethimide and its analogue rogletimide on peripheral aromatisation in breast cancer. [2019]

14. Japan pubmed.ncbi.nlm.nih.gov

[Experimental multihormone therapy on human breast carcinomas grown in nude mice]. [2013]

15. Australia pubmed.ncbi.nlm.nih.gov

Response to aminoglutethimide after tamoxifen therapy in advanced breast cancer. [2021]