Trial Outcomes & Findings for Mirvetuximab Soravtansine as First Line in Treating Patients With Triple Negative Breast Cancer (NCT NCT03106077)

Results Overview

Determine if Mirvetuximab Soravtansine as a Single Agent is Likely to Induce Response in at Least 20% of Patients With Metastatic Folate Receptor (FR) Alpha+ Triple Negative Breast Cancer (TNBC). Per Response Evaluation Criteria In Solid Tumors Criteria (RECIST v1.1) for target lesions and assessed by MRI: Complete Response (CR), Disappearance of all target lesions; Partial Response (PR), \>=30% decrease in the sum of the longest diameter of target lesions; Overall Response (OR) = CR + PR.

Recruitment status

COMPLETED

Study phase

PHASE2

Target enrollment

96 participants

Primary outcome timeframe

From the registration to the study until disease progression or death from any cause, whichever occurred first, assessed up to 2 years

Results posted on

2020-12-02

Participant Flow

96 participants signed consent, 54 enrolled during prescreening and 42 enrolled during enrollment, 94 were ineligible due to 4 died prior to starting treatment, 1 found not to be Triple negative breast cancer, 4 withdrew, 73 FR alpha negative, 11 insufficient tissue for analysis of FR alpha and 1 trial closed prior to enrollment.

Participant milestones

Participant milestones
Measure	Cohort A: Advanced Triple-Negative Breast Cancer (TNBC) 6 mg/kg IMGN853 IV Q3W	Cohort B: Localized Breast Cancer 6 mg/kg IMGN853 IV Q3W for 4 cycles
Overall Study STARTED	96	0
Overall Study COMPLETED	2	0
Overall Study NOT COMPLETED	94	0

Reasons for withdrawal

Reasons for withdrawal
Measure	Cohort A: Advanced Triple-Negative Breast Cancer (TNBC) 6 mg/kg IMGN853 IV Q3W	Cohort B: Localized Breast Cancer 6 mg/kg IMGN853 IV Q3W for 4 cycles
Overall Study Screen Failure	94	0

Baseline Characteristics

Mirvetuximab Soravtansine as First Line in Treating Patients With Triple Negative Breast Cancer

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Cohort A: Advanced Triple-Negative Breast Cancer(TNBC) n=2 Participants 6 mg/kg IMGN853 IV Q3W
Age, Continuous	40 years n=5 Participants
Sex: Female, Male Female	2 Participants n=5 Participants
Sex: Female, Male Male	0 Participants n=5 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	0 Participants n=5 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	2 Participants n=5 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	0 Participants n=5 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants n=5 Participants
Race (NIH/OMB) Asian	0 Participants n=5 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=5 Participants
Race (NIH/OMB) Black or African American	0 Participants n=5 Participants
Race (NIH/OMB) White	2 Participants n=5 Participants
Race (NIH/OMB) More than one race	0 Participants n=5 Participants
Race (NIH/OMB) Unknown or Not Reported	0 Participants n=5 Participants
Region of Enrollment United States	2 participants n=5 Participants

PRIMARY outcome

Timeframe: From the registration to the study until disease progression or death from any cause, whichever occurred first, assessed up to 2 years

Population: We did not enroll enough patients to determine if 20% of patients with metastatic FR+ had a response to mirvetuximab soravtansine.

Determine if Mirvetuximab Soravtansine as a Single Agent is Likely to Induce Response in at Least 20% of Patients With Metastatic Folate Receptor (FR) Alpha+ Triple Negative Breast Cancer (TNBC). Per Response Evaluation Criteria In Solid Tumors Criteria (RECIST v1.1) for target lesions and assessed by MRI: Complete Response (CR), Disappearance of all target lesions; Partial Response (PR), \>=30% decrease in the sum of the longest diameter of target lesions; Overall Response (OR) = CR + PR.

Outcome measures

Outcome measures
Measure	Cohort A: Advanced Triple-Negative Breast Cancer (TNBC) n=2 Participants 6 mg/kg IMGN853 IV Q3W
Number of Metastatic Participants With Radiographic Response	0 Participants

PRIMARY outcome

Timeframe: From baseline to the study until disease progression or surgery, assessed up to 6 months

Population: We did not enroll patients in this cohort and no data was collected for this cohort.

Determine if mirvetuximab soravtansine as a single agent in the neoadjuvant setting will improve rates of excellent pathologic response (pathologic complete response \[pCR\]/residual cancer burden \[RCB\]-0 or RCB-I) from 5% to 20% in patients with high risk, chemotherapy insensitive, FRalpha+ TNBC.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: From the baseline to the study until disease progression or death from any cause, whichever occurred first

Tumor response for patients with measurable lesions should be assessed using RECIST 1.1 (Eisenhauer 2009, 0). Patients with measurable lesions should be assessed using CT or MRI scan approximately every second cycle, from the date of first dose until the 30-day Follow-up visit. Although progression may be determined by the investigator based upon clinical deterioration, every effort should be made to document progression using radiographic methods. The basis for determination of progression per clinical deterioration should be documented.

Outcome measures

Outcome measures
Measure	Cohort A: Advanced Triple-Negative Breast Cancer (TNBC) n=2 Participants 6 mg/kg IMGN853 IV Q3W
Number of Participants With Radiographic Response Rate	2 Participants

SECONDARY outcome

Timeframe: From the baseline to the study until disease progression or death from any cause, whichever occurred first

Outcome measures

Outcome measures
Measure	Cohort A: Advanced Triple-Negative Breast Cancer (TNBC) n=2 Participants 6 mg/kg IMGN853 IV Q3W
Number of Participants With Stable Disease	1 Participants

SECONDARY outcome

Timeframe: From the baseline to the study until disease progression or death from any cause, whichever occurred first

Progression is defined using Response Evaluation Criteria In Solid Tumors Criteria (RECIST v1.1), as a 20% increase in the sum of the longest diameter of target lesions, or a measurable increase in a non-target lesion, or the appearance of new lesions.

Outcome measures

Outcome measures
Measure	Cohort A: Advanced Triple-Negative Breast Cancer (TNBC) n=2 Participants 6 mg/kg IMGN853 IV Q3W
Number of Participants With Progressive Disease	1 Participants

SECONDARY outcome

Timeframe: From the date of enrollment/baseline of the study until disease progression or death from any cause, whichever occurred first, up to 2 years

Determine duration of response metastatic TNBC patients treated with mirvetuximab soravtansine .

Outcome measures

Outcome measures
Measure	Cohort A: Advanced Triple-Negative Breast Cancer (TNBC) n=2 Participants 6 mg/kg IMGN853 IV Q3W
Number of Metastatic Participants With Duration of Response	2 Participants

SECONDARY outcome

Timeframe: From the date of enrollment/baseline of the study until disease progression or death from any cause, whichever occurred first

Population: We did not enroll patients in cohort A and no data was collected for this cohort.

Compare disease response (as measured by pCR/RCB-I) in patients with FRalpha+ chemotherapy resistant disease treated on clinical trial with mirvetuximab soravtansine in the neoadjuvant setting to those with similar molecular features who receive standard taxane-based chemotherapy as the second phase of their NACT

Outcome measures

Outcome data not reported

Adverse Events

Cohort A: Advanced Triple-Negative Breast Cancer (TNBC)

Serious events: 0 serious events

Other events: 2 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Other adverse events
Measure	Cohort A: Advanced Triple-Negative Breast Cancer (TNBC) n=2 participants at risk 6 mg/kg IMGN853 IV Q3W
Blood and lymphatic system disorders Neutropenia	50.0% 1/2 • Number of events 1 • Adverse events collected from the initiation of study drugs up to last dose of study drugs, up to 2 years
Eye disorders Grade 1 Blurred Vision	50.0% 1/2 • Number of events 1 • Adverse events collected from the initiation of study drugs up to last dose of study drugs, up to 2 years
Eye disorders Grade 2 Blurred Vision	50.0% 1/2 • Number of events 1 • Adverse events collected from the initiation of study drugs up to last dose of study drugs, up to 2 years
Eye disorders Keratopathy	50.0% 1/2 • Number of events 1 • Adverse events collected from the initiation of study drugs up to last dose of study drugs, up to 2 years
Nervous system disorders Peripheral	50.0% 1/2 • Number of events 1 • Adverse events collected from the initiation of study drugs up to last dose of study drugs, up to 2 years
Musculoskeletal and connective tissue disorders Neutropathy	50.0% 1/2 • Number of events 1 • Adverse events collected from the initiation of study drugs up to last dose of study drugs, up to 2 years
Musculoskeletal and connective tissue disorders Myalgia	50.0% 1/2 • Number of events 1 • Adverse events collected from the initiation of study drugs up to last dose of study drugs, up to 2 years
Hepatobiliary disorders Elevated liver enzymes	50.0% 1/2 • Number of events 1 • Adverse events collected from the initiation of study drugs up to last dose of study drugs, up to 2 years

Additional Information

Stacy Moulder, Professor, Breast Medical Oncology

UT MD Anderson Cancer Center

Phone: (713) 792-2817

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place