Elena Maroto-Martin, PhD, of Dana-Farber Cancer Institute, discusses early efficacy data on an MZB1-targeted T-cell receptor (TCR)–like CAR T-cell therapy in preclinical models of multiple myeloma and Waldenström macroglobulinemia. The therapy demonstrated strong tumor cell killing and specificity against MZB1/HLA-A2–positive cells, including primary patient samples. It also showed HLA cross-reactivity, targeting MZB1 presented by other HLA alleles such as HLA-A24/A23. In vivo, the treatment eradicated tumor cells and prolonged overall survival in a humanized multiple myeloma model. These findings support further development of TCR-like CAR T therapies targeting intracellular antigens in multiple myeloma and other B-cell malignancies.
Robert Herman Vonderheide, MD, DPhil, of Penn Medicine, discusses preclinical data demonstrating that KRAS(ON) multi-selective inhibitors produce significant tumor regression in pancreatic ductal adenocarcinoma models. The antitumor effect was notably reduced in animals lacking T cells, indicating that the adaptive immune system plays a crucial role in the therapeutic response. Adding immune therapies, such as checkpoint inhibitors, further deepened tumor regressions and, in some cases, led to sustained remissions. These findings support combining RAS(ON) inhibitors like RMC-6236 with immunotherapy in clinical trials, including the ongoing phase 1/1b study (NCT05379985) for patients with KRAS G12-mutant solid tumors.
Jorge A. Garcia, MD, of University Hospitals Seidman Cancer Center and Case Comprehensive Cancer Center, discusses the safety of using lutetium Lu 177 vipivotide tetraxetan (Pluvicto) earlier in the treatment of prostate-specific membrane antigen–positive metastatic castration-resistant prostate cancer (mCRPC). The FDA expanded its indication based on the phase 3 PSMAfore trial (NCT04689828), which showed improved radiographic progression-free survival vs a change in androgen receptor pathway inhibitor therapy. Garcia notes that the safety profile in this earlier, chemotherapy-naive setting remains favorable, with common adverse effects (AEs) including fatigue and anemia, mostly of low grade. Grade 3 or higher AEs were uncommon, and discontinuation due to toxicity was low, supporting the tolerability of earlier use of this radioligand therapy.
Erica Maria Pimenta, MD, of Dana-Farber Cancer Institute and Brigham and Women’s Hospital, discusses the ongoing challenges and unmet needs in treating soft tissue sarcomas, particularly dedifferentiated liposarcoma (DDLPS). She highlights that current treatment relies heavily on empiric chemotherapy, which offers limited benefit and significant toxicity, underscoring the need for targeted therapies. Pimenta explains that research is focusing on understanding the molecular and epigenetic drivers of DDLPS to identify new biomarkers and therapeutic targets. Despite previous modest results with immune checkpoint inhibitors and targeted agents, she is optimistic that deeper insights into tumor heterogeneity and the tumor microenvironment will improve future trial design and patient outcomes.