Trastuzumab deruxtecan (T-DXd) was approved in December 2022 by the FDA for patients with pretreated HER2- positive breast cancer based on the results of the phase III trial Destiny-Breast03 [3], showing an impressive improvement in progression-free survival with an hazard ratio of 0.33 (95% CI 0.26– 0.43, p-value<0.0001) compared to T-DM1, according to the last update presented at SABCS 2022 [4]...Besides T-DXd and SYD985, other ADCs have been or are under investigation, including, but not limited to, patritumab deruxtecan, disitamab vedotin, XMT-1522, MM-302, MEDI-4276, A166, ARX788, BAT8001 and PF-06804103...Several TKIs have been successfully developed, with tucatinib being the latest to enter clinical practice based on the results of the HER2CLIMB trial [7], with particular importance for patients with brain metastases. Other promising emerging treatments targeting HER2/3 receptors are the HER2- targeted bispecific antibodies (including, among others, KN026 and zanidatamab) and the anti-HER3 monoclonal antibodies; for both classes, clinical trials are ongoing...In the early setting, the first large, randomized, phase III trial testing the addition of an ICI (atezolizumab) to neoadjuvant dual-anti HER2 blockade and chemotherapy was negative [10]...In the phase Ib B-PRECISE-01 study (NCT03767335) the PI3 K inhibitor izorlisib (MEN1611) was tested in combination with trastuzumab ± fulvestrant in patients with HER2-positive/PIK3CA mutated metastatic breast cancer, showing a manageable safety profile with encouraging anti-tumor activity in heavily pre-treated patients (34.1% of partial responses, 2.4% complete response, 56.1% stable disease)...Thus, due to the close crosstalk between ER and HER2 receptor pathways, the simultaneous blockade of both signaling pathways represents a promising approach to prevent the onset of mechanisms of resistance. Large evidence supports the combination of endocrine and anti-HER2 therapies (often as maintenance treatment), while new strategies with novel agents (including novel SERDs, and CDK4/6i) are currently being investigated.

ICIs improve survival after platinum-based chemotherapy. Avelumab maintenance represents a new practice-changing treatment. The combinations of ICIs and other compounds, such as FGFR-inhibitors, antibody-drug conjugates, and anti-angiogenic drugs, represent promising therapeutic approaches. Biomarkers with predictive roles and sequencing strategies are warranted for best patient selection.

These trials will help us to deepen our understanding of the pathogenesis of AML and facilitate the best immunotherapeutic strategy in AML. We discuss here the mode of action of immune-based therapies and provide an overview of the available data.