Phase 3 Study to Evaluate the Efficacy and Safety of HER2/Neu Peptide GLSI-100 (GP2 + GM-CSF) in HER2/Neu Positive Subjects (FLAMINGO-01)

• ClinicalTrials.gov Identifier: NCT05232916
• Recruitment Status: Recruiting
• First Posted: February 10, 2022
• Last Update Posted: May 3, 2024
• Sponsor: Greenwich LifeSciences, Inc.
• Information provided by (Responsible Party): Greenwich LifeSciences, Inc.

Tracking Information

• First Submitted Date: January 31, 2022
• First Posted Date: February 10, 2022
• Last Update Posted Date: May 3, 2024
• Actual Study Start Date: August 11, 2022
• Estimated Primary Completion Date: December 2026 (Final data collection date for primary outcome measure)

Current Primary Outcome Measures (submitted: February 13, 2022)

Invasive Breast Cancer-free Survival (IBCFS) [ Time Frame: Median 4 years of follow-up (interim analysis planned) ]

IBCFS is defined as the time from the first dose of study medication until the date of ipsilateral invasive breast cancer recurrence, ipsilateral local-regional invasive breast cancer recurrence, distant recurrence, contralateral invasive breast cancer, or any cause mortality.

Original Primary Outcome Measures (submitted: January 31, 2022)

Invasive Breast Cancer-free Survival (IBCFS) [ Time Frame: Over 4 years of follow-up ]

IBCFS is defined as the time from the first dose of study medication until the date of ipsilateral invasive breast cancer recurrence, ipsilateral local-regional invasive breast cancer recurrence, distant recurrence, contralateral invasive breast cancer, or any cause mortality.

Current Secondary Outcome Measures (submitted: February 13, 2022)

• Invasive Disease-free Survival (IDFS) [ Time Frame: Median 4 years of follow-up (interim analysis planned) ]
  IDFS is defined as the time from the first dose of study medication until the date of ipsilateral invasive breast cancer recurrence, ipsilateral local-regional invasive breast cancer recurrence, distant recurrence, contralateral invasive breast cancer, second primary non-breast invasive cancer, or any cause mortality.
• Distant Disease-free Survival (DDFS) [ Time Frame: Median 4 years of follow-up (interim analysis planned) ]
  DDFS will be defined as the time from the first dose of study medication to the time of distant disease recurrence or death.
• Overall Survival [ Time Frame: Median 4 years of follow-up (interim analysis planned) ]
  Overall survival will be defined as the time from the first dose of study medication until death from any cause.
• Quality of Life Questionnaire Core 30 (QLQ-C30) [ Time Frame: Baseline and 36 months ]
  European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire Core 30 (QLQ-C30)
• Quality of Life FACT-GP5 [ Time Frame: Baseline and 36 months ]
  FACT-GP5 to assess global side effect impact

Original Secondary Outcome Measures (submitted: January 31, 2022)

• Invasive Disease-free Survival (IDFS) [ Time Frame: Over 4 years of follow-up ]
  IDFS is defined as the time from the first dose of study medication until the date of ipsilateral invasive breast cancer recurrence, ipsilateral local-regional invasive breast cancer recurrence, distant recurrence, contralateral invasive breast cancer, second primary non-breast invasive cancer, or any cause mortality.
• Distant Disease-free Survival (DDFS) [ Time Frame: Over 4 years of follow-up ]
  DDFS will be defined as the time from the first dose of study medication to the time of distant disease recurrence or death.
• Overall Survival [ Time Frame: Over 4 years of follow-up ]
  Overall survival will be defined as the time from the first dose of study medication until death from any cause.
• Quality of Life Questionnaire Core 30 (QLQ-C30) [ Time Frame: Baseline and 36 months ]
  European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire Core 30 (QLQ-C30)
• Quality of Life FACT-GP5 [ Time Frame: Baseline and 36 months ]
  FACT-GP5 to assess global side effect impact

Current Other Pre-specified Outcome Measures (submitted: January 31, 2022)

Immune Response Measurements [ Time Frame: Screening, Baseline, Month 1, Month 2, Month 3, Month 4, Month 5, Month 6, Month 12, Month 13, Month 18, Month 19, Month 24, Month 25, Month 30, Month 31, Month 36, Month 37, Month 42, Month 48 ]

Immune response will be measured by Delayed-Type Hypersensitivity (DTH) tests and immunologic assays.

• Original Other Pre-specified Outcome Measures: Same as current

Descriptive Information

• Brief Title: Phase 3 Study to Evaluate the Efficacy and Safety of HER2/Neu Peptide GLSI-100 (GP2 + GM-CSF) in HER2/Neu Positive Subjects
• Official Title: A Randomized, Multicenter, Placebo-controlled, Phase 3 Study to Evaluate the Efficacy and Safety of HER2/Neu Peptide GLSI-100 (GP2 + GM-CSF) in HER2/Neu Positive Subjects With Residual Disease or High-Risk PCR After Both Neoadjuvant and Postoperative Adjuvant Trastuzumab-based Therapy (FLAMINGO-01)
• Brief Summary: This is a prospective, randomized, double-blinded, placebo-controlled, multi-center, Phase 3 study of GLSI-100 immunotherapy in HLA-A*02 positive and HER2/neu positive subjects who are at high risk for disease recurrence and have completed both neoadjuvant and postoperative adjuvant standard of care therapy. Treatment consists of 6 intradermal injections, Primary Immunization Series (PIS), over the first 6 months of treatment and 5 booster intradermal injections spaced 6 months apart. A third open-label arm will explore GLSI-100 immunotherapy in non-HLA-A*02 positive and HER2/neu positive subjects.
• Detailed Description: Not Provided
• Study Type: Interventional
• Study Phase: Phase 3

Study Design

Allocation: Randomized
Intervention Model: Parallel Assignment
Intervention Model Description:

HLA-A*02 subjects will be randomized to GLSI-100 or placebo. Treatment consists of 6 intradermal injections, Primary Immunization Series (PIS), over the first 6 months of treatment and 5 booster intradermal injections spaced 6 months apart. A third open-label arm will explore GLSI-100 immunotherapy in non-HLA-A*02 positive and HER2/neu positive subjects.

Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Masking Description:

Double-blind

Primary Purpose: Prevention

• Condition: Breast Cancer

Intervention

• Biological: Placebo
  0.9% Normal Saline
• Biological: GLSI-100
  500 mcg/mL GP2 and 125 mcg/mL GM-CSF

Study Arms

• Placebo Comparator: 0.9% Normal Saline
  0.9% normal saline in HLA-A*02 positive and HER2/neu positive subjects administered intradermally every month for first 6 months then every 6 months for next 2.5 years (11 intradermal injections over 3 years)
  Intervention: Biological: Placebo
• Experimental: GLSI-100
  GLSI-100 immunotherapy in HLA-A*02 positive and HER2/neu positive subjects administered intradermally every month for first 6 months then every 6 months for next 2.5 years (11 intradermal injections over 3 years)
  Intervention: Biological: GLSI-100
• Experimental: GLSI-100, Open-label
  Open-label arm: GLSI-100 immunotherapy in non-HLA-A*02 positive and HER2/neu positive subjects administered intradermally every month for first 6 months then every 6 months for next 2.5 years (11 intradermal injections over 3 years)
  Intervention: Biological: GLSI-100

• Publications *: Not Provided

Recruitment Information

• Recruitment Status: Recruiting
• Estimated Enrollment (submitted: January 31, 2022): 598
• Original Estimated Enrollment: Same as current
• Estimated Study Completion Date: December 2026
• Estimated Primary Completion Date: December 2026 (Final data collection date for primary outcome measure)

Eligibility Criteria

Inclusion Criteria:

• HLA-A*02-positive, unless being enrolled in the third non-HLA-A*02 arm
• Histologically confirmed diagnosis of HER2/neu positive primary breast cancer
• Completion of both neoadjuvant and adjuvant trastuzumab-based standard of care breast cancer therapy
• Stage I, II, or III at presentation with pathologic evidence of residual invasive carcinoma in the breast or axillary lymph nodes (residual disease) at surgery following completion of neoadjuvant therapy -OR- Stage III at presentation with pathologic complete response (pCR) at surgery following completion of neoadjuvant therapy
• The subject can begin study therapy within one year of completion of adjuvant trastuzumab-based therapy and any other standard therapies, but, study therapy can be administered concurrently with endocrine therapy.
• No clinical evidence of residual or persistent breast cancer per treating physician assessment
• ECOG 0-2
• Adequate organ function
• Negative pregnancy test or evidence of post-menopausal status
• If of childbearing potential, willing to use a form of highly effective contraception

Exclusion Criteria:

• Stage IV cancer or metastatic breast cancer at any time
• Inflammatory breast cancer
• Receiving other investigational agents
• Receiving chemotherapy
• Requiring long-term systemic treatment with corticosteroids or other immunosuppressive therapy
• History of immunodeficiency or active autoimmune disease
• A history of serious allergic reactions, including anaphylaxis, to human granulocyte-macrophage colony-stimulating factors such as sargramostim, yeast-derived products, or any component of the investigational product
• Other malignancies except adequately treated in situ carcinoma of the cervix or basal cell or squamous cell carcinoma of the skin
• Active infection
• Known HIV infection with a detectable viral load within 6 months of the anticipated start of treatment. Note: Subjects on effective antiretroviral therapy with an undetectable viral load within 6 months of the anticipated start of treatment are eligible for this trial.

Sex/Gender

• Sexes Eligible for Study: All

• Ages: 18 Years to 100 Years (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Contacts

Contact: Jaye L Thompson, Ph.D.; (832) 791-2542; Jaye.Thompson@GreenwichLifeSciences.com

• Listed Location Countries: France, Germany, Italy, Poland, Spain, United States

Administrative Information

• NCT Number: NCT05232916
• Other Study ID Numbers: GLSI-21-01
• Has Data Monitoring Committee: Yes

U.S. FDA-regulated Product

• Studies a U.S. FDA-regulated Drug Product: Yes
• Studies a U.S. FDA-regulated Device Product: No

IPD Sharing Statement

• Plan to Share IPD: No

• Current Responsible Party: Greenwich LifeSciences, Inc.
• Original Responsible Party: Same as current
• Current Study Sponsor: Greenwich LifeSciences, Inc.
• Original Study Sponsor: Same as current
• Collaborators: Not Provided

Investigators

• Principal Investigator: Mothaffar F Rimawi, MD; Baylor College of Medicine

• PRS Account: Greenwich LifeSciences, Inc.
• Verification Date: May 2024