RESUMO
BACKGROUND: This exploratory pooled analysis investigated the efficacy and safety of trastuzumab deruxtecan (T-DXd) versus comparator treatment in patients with human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (mBC) with brain metastases (BMs) at baseline, categorized according to previous local treatment. PATIENTS AND METHODS: T-DXd data were pooled from DESTINY-Breast01/-02/-03. Comparator data, from patients receiving physician's choice therapy and trastuzumab emtansine, were pooled from DESTINY-Breast02 and -03, respectively. Baseline BM status was assessed according to US Food and Drug Administration criteria. The endpoints included intracranial objective response rate (ORR; complete or partial response in the brain) per blinded independent central review (BICR) by RECIST version 1.1, time to intracranial response, intracranial duration of response (DoR), central nervous system progression-free survival (CNS-PFS) by BICR, overall survival (OS), and safety. RESULTS: A total of 148 patients who received T-DXd and 83 patients who received comparator treatment had BMs at baseline. In those treated with T-DXd, the intracranial ORR of patients with treated/stable and untreated/active BMs was 45.2% and 45.5%, respectively. The median (range) time to intracranial response was 2.8 months (1.1-13.9 months) and 1.5 months (1.2-13.7 months) in patients with treated/stable and untreated/active BMs, respectively. For those with treated/stable BMs, the median intracranial DoR was 12.3 [95% confidence interval (CI) 9.1-17.9] months, and for those with untreated/active BMs, it was 17.5 months (95% CI 13.6-31.6 months). The median CNS-PFS and OS were 12.3 months (95% CI 11.1-13.8 months) and not reached (95% CI 22.1 months-not estimable) in those with treated/stable BMs, and 18.5 months (95% CI 13.6-23.3 months) and 30.2 months (95% CI 21.3 months-not estimable) in those with untreated/active BMs, respectively. Drug-related treatment-emergent adverse events grade ≥3 were experienced by 43.2% of patients with BMs and 46.4% without BMs with T-DXd. CONCLUSIONS: T-DXd demonstrated meaningful intracranial efficacy and clinical benefit in OS, with an acceptable and manageable safety profile in patients with HER2-positive mBC with treated/stable and untreated/active BMs.
RESUMO
BACKGROUND: To investigate in the NeoSphere trial the contribution of the immune system to pathologic complete response in the breast (pCRB) after neoadjuvant docetaxel with trastuzumab (TH), pertuzumab (TP), or both (THP), or monoclonal antibodies alone (HP). PATIENTS AND METHODS: Immune gene mRNA expression (n = 350, 83.8%), lymphocyte infiltration (TIL, n = 243, 58.3%), and PDL1 by immunohistochemistry (n = 305, 73.1%) were correlated with pCRB. We studied five selected genes (IFNG, PD1, PDL1, PDL2, CTLA4) and six immune metagenes corresponding to plasma cells (IGG), T cells (CD8A), antigen-presenting cells (MHC2), and to MHC1 genes (MHC1), STAT1 co-expressed genes (STAT1), and interferon-inducible genes (IF-I). Gene expression data from the NOAH trial were used for validation. RESULTS: TIL as continuous variable and PDL1 protein expression were not significantly associated with pCRB. Expression of immune genes/metagenes had different association with pCRB after THP than after other therapies. With THP, higher expression of PD1 and STAT1, or any among PDL1, CTLA4, MHC1, and IF-I were linked with lower pCRB. In the combined TH/TP/HP treatment group, in multivariate analysis, higher expression of PD1, MHC2, and STAT1 were linked with pCRB, and higher PDL1, MHC1, or IF-I to lower pCRB. In the NOAH, a similar association of higher STAT1 with higher pCRB, and higher MHC1 and IF-I with lower pCRB was found for trastuzumab/chemotherapy but not for chemotherapy treatment only. CONCLUSIONS: The immune system modulates response to therapies containing trastuzumab and pertuzumab. Greatest benefit from THP is observed for low expression of some immune markers (i.e. MHC1, CTLA4). The involvement of PDL1 in resistance supports testing combinations of HER2-directed antibodies and immune-checkpoint inhibitors.