Mark Pegram, MD, Spoke About Major ASCO Presentations In Breast Cancer

Mark Pegram, MD, discussed the highlights from ASCO 2022, regarding antibody drug conjugates.

Mark Pegram, MD, Suzy Yuan-Huey Hung Endowed Professor of Medical Oncology at Stanford University School of Medicine, spoke with CancerNetwork® at the 2022 American Society of Clinical Oncology (ASCO) Annual Meeting, about recent updates from the conference. He discussed the most popular presentations as well as data from his own study which assessed the utility of the Breast Cancer Index (BCI) score, based on the HOXB13/IL17RB (H/I) ratio, and Clinical Treatment Score Post-5 years (CTS5) for determine endocrine therapy duration in patients treated on the IDEAL trial.1


At ASCO 2022, there have been so many exciting breakthrough presentations in the breast cancer arena. We have the advent of new antibody-drug conjugates that are working even in [patients with] hormone receptor­–positive disease, particularly in those who have low expression levels of the HER2 protein and who benefit from trastuzumab deruxtecan [Enhertu].2 Then there’s another study of saciztuzumab govitecan [Trodelvy], another antibody-drug conjugate [that works] directly against TROP2 as the target, and with a topoisomerase-1 inhibitor payload. That molecule had updated data presented that showed that that molecule is active in hormone receptor–positive metastatic breast cancer as well.3 We saw exciting drug combinations, particularly with the new drug class of orally bioavailable SERDs, that is the selective estrogen receptor degraders. Now the first generation of trials of oral SERDs have been largely completed. We’re seeing more exciting data as numerous drugs in this class are in the midst of phase III trials.

The oral SERD drugs are now in clinical investigations in moving into the early-stage disease setting, many of them having “graduated” from the clinical investigation in the metastatic setting previously. There were also breakthroughs presented at ASCO in the area of diagnostics. This translational BCI [Breast Cancer Index] data was a highlight as it applied to the IDEAL clinical trial, and was a strength of the ASCO meeting this year. While there’s a lot of work left to be done, I’m also very excited about the potential of antibody-drug conjugate technology extending beyond cytotoxic payloads. For instance, we have 2 trials at my institution where we’re adding immunologic payloads to therapeutic antibodies instead of chemotherapy payloads to antibody-drug conjugates. That’s another exciting approach that is moving into the clinic. Hopefully, it will pan out with more effective and less toxic therapies for our patients.


  1. Liefers G-J, Noordhoek I, Putter H, et al. Predictive performance of breast cancer index (BCI) and clinical treatment score post-5 years (CTS5) in the IDEAL study. J Clin Oncol. 2022;40(suppl 16):545. doi:10.1200/JCO.2022.40.16_suppl.545
  2. Modi S, Jacot W, Yamashita T, et al. Trastuzumab deruxtecan (T-DXd) versus treatment of physician’s choice (TPC) in patients (pts) with HER2-low unresectable and/or metastatic breast cancer (mBC): results of DESTINY-Breast04, a randomized, phase 3 study. J Clin Oncol. 2022;40(suppl 17):LBA3. doi:10.1200/JCO.2022.40.17_suppl.LBA3
  3. Rugo HS, Bardia A, Marme F, et al. Primary results from TROPiCS-02: A randomized phase 3 study of sacituzumab govitecan (SG) versus treatment of physician’s choice (TPC) in patients (Pts) with hormone receptor–positive/HER2-negative (HR+/HER2-) advanced breast cancer. J Clin Oncol. 2022; 40(suppl 17):LBA1001. doi: 10.1200/JCO.2022.40.17_suppl.LBA1001