, according to the most recent analysis of data from the phase 3 AEGEAN study.
“In terms of cancellation of surgery, surgical delay, surgically related adverse events, complications, operation time, and operation procedure, there was no difference between the durvalumab group and the placebo group. In addition, the R0 resection rate was numerically higher in the durvalumab group. These [results] indicate that adding perioperative durvalumab did not adversely affect surgical outcomes,” wrote Tetsuya Mitsudomi, MD, PhD, who presentedat the annual World Conference on Lung Cancer, in an email. The topline results of AEGEAN were earlier this year at AACR 2023, which showed that the regimen combined with adjuvant durvalumab improved event-free survival (EFS) and pathologic complete response (pCR), compared with chemotherapy plus placebo.
Dr. Mitsudomi also pointed out that AEGEAN is one of the first studies looking at immune checkpoint inhibitors (ICI) in the perioperative settings that demonstrated improved EFS and pCR with no effect on surgical outcomes. Previously, thedemonstrated efficacy of neoadjuvant ICI alone.
“The AEGEAN study showed that neoadjuvant plus adjuvant ICI is another option for these patients. However, no one knows who should receive the postoperative ICI in addition to neoadjuvant ICI, because there are no trials including ongoing ones that ask this question,” wrote Dr. Mitsudomi.
The phase 3 AEGEAN study included 740 patients who were randomized to durvalumab or placebo. The median age was 65.0 years in both groups, and 33.3% and 33.4% of patients in each group respectively had fewer than 1% of tumor cells that expressed PD-L1. Expression in 1-49% of tumor cells occurred in 36.9% and 38.0% respectively, and expression ≥ 50% occurred in 29.8% and 28.6%.
Prior to surgery, 84.7% of the durvalumab arm completed four cycles of chemotherapy, as did 87.2% in the placebo arm. The proportion of patients undergoing surgery was 80.6% and 80.7% in the two arms, respectively, and surgical completion was achieved in 77.6% and 76.7%. The durvalumab arm and placebo arm had similar median times from last neoadjuvant treatment to surgery (34.0 days for both) and median time from surgery to first adjuvant dose (50.0 versus 52.0 days).
Among patients with stage II NSCLC, 84.3% in the durvalumab arm underwent surgery, versus 88.9% in the placebo arm. Among patients with stage III disease, the numbers were 79.2% and 77.4%, respectively. There was no surgical delay in 82.7% of patients in the durvalumab arm, compared with 77.8% in the placebo arm. The most common reason for surgical delay was logistical reasons. Mediastinal lymph node dissection was completed in 86.6% of the durvalumab arm and 84.7% of the placebo arm. In both groups where surgery was completed, R0 resection rates were over 90% overall as well as in both stage I and stage II patients. Following surgery, adverse events possibly related to surgery occurred in 40.2% of the durvalumab group and 39.2% of the placebo group. The most common surgical adverse events occurred at similar frequency between groups.
After the presentation, Solange Peters, MD, PhD, served as a discussant. She pointed out other studies that have examined ICI therapy for NSCLC in both the neoadjuvant and adjuvant setting, including(pembrolizumab), (toripalimab), CheckMate 77T (nivolumab), and (atezolizumab). She pointed out that AEGEAN, Keynote-671, CheckMate 816, and NeoTorch all had similar trial designs and showed similar magnitude of benefit. “We have a growing paradigm [for combining neoadjuvant and adjuvant ICI therapy]. We are quite all convinced in the community that there is a biological rationale to use neoadjuvant immunotherapy because of the fit immune system, because of the presence of the neoantigens within the tumor at the time of the start of neoadjuvant treatment, [leading to] better priming of immune cells,” said Dr. Peters, who is a professor of medical oncology at University Hospital of Lausanne, Switzerland.
About one in five patients across the trials who would be eligible for surgery never undergo it, but there is promising data from CheckMate 816 that neoadjuvant ICB may improve the odds of surgery, according to Dr. Solange. The AEGEAN data produced some “quite interesting” data about the reasons that patients don’t make it to surgery, as it showed that 8%-10% of patients don’t reach surgery because of progression, but 10%-15% may fall out because they turned out not to be a good candidate for surgery. “I think we probably have to blame the enthusiasm we have to add all these patients into the trial, hoping for the best for the patient but maybe making a wrong selection,” said Dr. Peters.
The study was funded by AstraZeneca. Dr. Mitsudomi has received speaker fees, honoraria, or research funding from AstraZeneca, Chugai, Ono, Bristol Myers Squibb, and MSD. Dr. Peters has financial relationships with AstraZeneca as well as a wide range of other pharmaceutical companies.