30May

SOPHIA analysis by chemotherapy (Ctx) choice: A phase III (P3) study of margetuximab (M) + Ctx versus trastuzumab (T) + Ctx in patients (pts) with pretreated HER2+ metastatic (met) breast cancer (MBC).


Abstract No : 1040

Abstract Type : Poster Discussion Session

Indication : Her2 Positive Breast Cancer

Intervention : margetuximab (M) + Ctx

Company : MacroGenics

Technology : Monoclonal Antibody


Results:

Investigator chemotherapy choices and results by chemotherapy are shown in the table. Subjects receiving Eri and Gem had the lowest PFS hazards ratios (HRs), favoring M over T, although no statistical significance of individual chemotherapy subgroups was seen. There was variable toxicity among Ctx subgroups, and fewer subjects receiving Cap had Ctx related Grade 3 or higher (.=Gr 3) AEs. In this unblinded study, more subjects on M than T in all subgroups discontinued Ctx while continuing study antibody.


Conclusion:

In combination with chemotherapy in pretreated HER2+ MBC, M improved PFS over T. Safety was manageable in all Ctx subgroups. Differences among HRs for chemotherapy subgroups may be driven by selection bias and/or sensitivity differences.


Refer to Her2 Positive Breast Cancer Market report for detailed Insights.