JCO fellow Dr. Ece Cali speaks with JCO Associate Editor Dr. Thomas E. Stinchcombe to discuss the JCO article "Phase 2 Dose-Randomized Study of Sunvozertinib in Platinum-Pretreated Non-Small-Cell Lung Cancer with Epidermal Growth Factor Receptor Exon 20 Insertion Mutations (WU-KONG1B)" , that was simultaneously released at the IASLC 2025 World Conference on Lung Cancer. TRANSCRIPT Dr. Ece Cali: Hello, and welcome to our series where we cover some of the top JCO papers published simultaneously with their abstract presentation at this year's most important oncology meetings. I am your host, Dr. Ece Cali, JCO editorial fellow, and I am joined by Dr. Tom Stinchcombe, JCO associate editor, to discuss the Journal of Clinical Oncology article and 2025 World Conference on Lung Cancer abstract presentation, " Phase II Dose-Randomized Study of Sunvozertinib in Platinum-Pretreated Non–Small Cell Lung Cancer With EGFR Exon 20 Insertion Mutations ." The WU-KONG1B trial is a multinational, phase II study that investigated the efficacy and safety of different doses of sunvozertinib in patients with metastatic non-small cell lung cancer and EGFR exon 20 insertion mutations after progression on platinum based chemotherapy. Tom, before we dive into the results, could you walk us through the rationale for this study, and how does it fit into the current treatment options for patients with EGFR exon 20 insertion? Dr. Tom Stinchcombe: Thank you, Dr. Cali. I think the clinical context is always important. We have known that EGFR exon 20 insertions exist and that they are resistant to our currently available EGFR tyrosine kinase inhibitors, and I think there have been attempts in the past to develop a tyrosine kinase inhibitor, but there is a very narrow therapeutic window between the dose you need to inhibit the EGFR mutation in the cancer and the EGFR receptor on normal tissues, most notably the mucosa, the gut, and the skin. And so, our previous attempts have failed largely because the dose required was not tolerable for patients and they could not really stay on the drug for a long time or they were not very active. And so, I think there was a real desire to develop an EGFR tyrosine kinase inhibitor, and then, historically, the standard had been a platinum based doublet as the standard of care. And more recently, platinum based doublet with amivantamab has proven to be superior to platinum based chemotherapy alone. I think the context is also important that amivantamab is not necessarily available in all the countries, and so, there are patients who do not have access to amivantamab. Going to the rationale, I think that this drug had shown preliminary promise of having activity but without that being encumbered by those EGFR wild type toxicities, and, therefore, it was really explored in this larger study. Dr. Ece Cali: And what are some key findings from this trial? Dr. Tom Stinchcombe: So, I think that we should look at the study design. It is a little quirky, for lack of a better term, in that there is a randomization to 200 versus 300 mg, and then, there was a nonrandomized cohort of 300 mg. So, when you look at the study, if you are a purist, you will just look at the randomized patients. If you are sort of an aggregator, you look at all patients. So, it shows reporting on three cohorts, but I think the key findings are that the 200 mg and the 300 mg treatments had similar toxicities in terms of response rate, duration of response, and progression free survival. And as you know going through the review, there was a lot of queries from the reviewers as to which would be the preferred dose, and to me, I think this really illustrates a dose finding component to a trial design because there is a lot of debate about what the minimal effective dose is or the optimal dose. And in this case, having the two dose cohorts did provide us some valuable efficacy and toxicity information. And then, when I look at the study, I want to make sure it reflects my patient population, and about a quarter of patients had brain metastases, and about 15% had previous amivantamab, and about 5% to 10% had another EGFR tyrosine kinase inhibitor. Dr. Ece Cali: And what is the objective response rate and the duration of response? These are pretty good numbers for this patient population. Dr. Tom Stinchcombe: In the 200 mg cohort, it was about 46%. The duration of response was around 11 months, and the PFS was around 8 months. The 300 mg cohort was 46%, duration of response 9.8, and the median PFS is 6.9 months, and I think that this is greater activity than we have seen with our previous attempts at EGFR tyrosine kinase inhibitors. Dr. Ece Cali: And based on these data, FDA granted accelerated approval for sunvozertinib very recently at 200 mg once daily dosing in this setting. So, that is a major step forward for our patients. Dr. Stinchcombe, how does this impact your clinical practice, and what side effects should oncologists be watching for if th
