Correlation between NK function and response to trastuzumab in metastatic breast cancer patients

<p>Abstract</p> <p>Background</p> <p>Trastuzumab is a monoclonal antibody selectively directed against Her2 and approved for the treatment of Her2 overexpressing breast cancer patients. Its proposed mechanisms of action include mediation of antibody-dependent cellular cytotoxicity (ADCC) by triggering FcγRIII on natural killer (NK) cells. This study addresses the correlation between overall NK function and trastuzumab's clinical activity.</p> <p>Subjects and methods</p> <p>Clinical and immunological responses were assessed in 26 patients receiving trastuzumab monotherapy as maintenance management after chemotherapy (8 mg/kg load and then standard doses of 6 mg/kg every 3 weeks). Cytotoxic activity against the MHC class I-negative standard NK target K562 cell line and HER2-specific ADCC against a trastuzumab-coated Her2-positive SKBR3 cell line were assessed in peripheral blood mononuclear cells (PBMC) harvested after the first standard dose. After six months, seventeen patients were scored as responders and nine as non-responders according to the RECIST criteria, while Progression-Free Survival (PFS) was calculated during a 12 months follow-up.</p> <p>Results</p> <p>The responders had significantly higher levels of both NK and ADCC activities (p < 0.05) that were not different from those of eleven normal controls. The NK activity of the non-responders was significantly (p < 0.05) lower than that of the normal controls. At twelve months, there was a marked correlation between PFS and NK activity only. PFS was significantly longer in patients with high levels of NK activity, whereas its pattern was unrelated to high or low ADCC activity.</p> <p>Conclusion</p> <p>One of the mechanisms of action of trastuzumab is NK cell-mediated ADCC lysis of the Her2-positve target cell. We show here that its potency is correlated with the short-term response to treatment, whereas longer protection against tumor expansion seems to be mediated by pure NK activity.</p

Demographic, tumor and clinical features of clinical trials versus clinical practice patients with HER2-positive early breast cancer: results of a prospective study

Several randomized clinical trials (RCTs) have demonstrated the efficacy of trastuzumab-based adjuvant therapy in HER2-positive breast cancer (BC). However, RCT patients may not invariably be representative of patients routinely seen in clinical practice (CP). To address this issue, we compared the clinical and tumor features of RCT and CP patients with HER2-positive BC

Trastuzumab with either docetaxel or vinorelbine as first-line treatment for patients with HER2-positive advanced breast cancer: a retrospective comparison

Abstract Background Combinations of trastuzumab with either docetaxel or vinorelbine are considered valuable treatment options for HER2-positive metastatic breast cancer patients. We performed a retrospective comparison of the clinical outcomes associated with either one of these combinations. Methods From a multi-institutional database we retrieved 179 patients treated with either docetaxel or vinorelbine plus trastuzumab as first-line therapy for HER2-positive advanced breast cancer. Results Docetaxel-trastuzumab was superior to vinorelbine-trastuzumab in terms of response rate (RR: 77 vs 57%, p = 0.01) and median overall survival (OS: 35 vs 23 months, p = 0.04), but not in median time to progression (TTP: 12 vs 10 months, p = 0.53). At multivariate analysis, type of treatment was not associated with TTP but was an independent predictor of OS, with a significant reduction in the risk of death in favor of docetaxel-trastuzumab (HR 0.474, 95% IC 0,303-0.742, p Conclusion Docetaxel or vinorelbine, when combined with trastuzumab, provide excellent rates of tumor control in patients with previously untreated HER2-positive advanced breast cancer. Docetaxel may offer some advantage in terms of response rate and resulted in a significantly prolonged overall survival, which, because of the retrospective design of our study, deserves further investigation in prospective trials.</p

Real-world ANASTASE study of atezolizumab+nab-paclitaxel as first-line treatment of PD-L1-positive metastatic triple-negative breast cancer

Abstract The combination of atezolizumab and nab-paclitaxel is recommended in the EU as first-line treatment for PD-L1-positive metastatic triple-negative breast cancer (mTNBC), based on the results of phase III IMpassion130 trial. However, ‘real-world’ data on this combination are limited. The ANASTASE study (NCT05609903) collected data on atezolizumab plus nab-paclitaxel in PD-L1-positive mTNBC patients enrolled in the Italian Compassionate Use Program. A retrospective analysis was conducted in 29 Italian oncology centers among patients who completed at least one cycle of treatment. Data from 52 patients were gathered. Among them, 21.1% presented de novo stage IV; 78.8% previously received (neo)adjuvant treatment; 55.8% patients had only one site of metastasis; median number of treatment cycles was five (IQR: 3–8); objective response rate was 42.3% (95% CI: 28.9–55.7%). The median time-to-treatment discontinuation was 5 months (95% CI: 2.8–7.1); clinical benefit at 12 months was 45.8%. The median duration of response was 12.7 months (95% CI: 4.1–21.4). At a median follow-up of 20 months, the median progression-free survival was 6.3 months (95% CI: 3.9–8.7) and the median time to next treatment or death was 8.1 months (95% CI: 5.5–10.7). At 12 months and 24 months, the overall survival rates were 66.3% and 49.1%, respectively. The most common immune-related adverse events included rash (23.1%), hepatitis (11.5%), thyroiditis (11.5%) and pneumonia (9.6%). Within the ANASTASE study, patients with PD-L1-positive mTNBC treated with first-line atezolizumab plus nab-paclitaxel achieved PFS and ORR similar to those reported in the IMpassion130 study, with no unexpected adverse events