Jan 20, 2022

André T, et al. Disclosures: André reports honoraria from, a consultant/advisory role with and/or travel, accommodations and expenses from Amgen, Astellas Pharma, AstraZeneca/MedImmune, Bristol Myers Squibb, GamaMabs Pharma, GlaxoSmithKline, Gritstone Oncology, Kaleido Biosciences, MSD Oncology, Pierre Fabre, Roche/Genentech, Seagen, Servier, Tesaro, Transgene and Ventana Medical Systems. Please see the abstract for all other researchers’ relevant financial disclosures. ADD TOPIC TO EMAIL ALERTS Receive an email when new articles are posted on Please provide your email address to receive an email when new articles are posted on . Subscribe ADDED TO EMAIL ALERTS Back to Healio We were unable to process your request. Please try again later. If you continue to have this issue please contact customerservice@slackinc.com . Back to Healio Neoadjuvant treatment with nivolumab and ipilimumab led to a high rate of pathologic complete response among patients with resectable microsatellite instability-high/mismatch repair deficient gastric cancers, study results showed. The combination also appeared feasible for these patients, according to results of the phase 2 GERCOR NEONIPIGA trial presented during Gastrointestinal Cancers Symposium. Data derived from André T, et al. “Patients with locally advanced esophagogastric junction or gastric adenocarcinoma with deficient mismatch repair have a better prognosis than those with proficient mismatch repair,” Thierry André, MD, professor of medical oncology at Sorbonne University and head of the medical oncology department at Saint-Antoine Hospital in Paris, said during a presentation. “Microsatellite instability-high/mismatch repair deficient [MSI/dMMR] status is predictive of efficacy of immune checkpoint inhibitors . Use of immune checkpoint inhibitors in this population before and/or after radical surgery might improve outcomes.” Rationale and methodology GERCOR NEONIPIGA enrolled 32 patients (median age, 65 years; range, 40-84; 72% men) with resectable MSI/dMMR tumors, including 16 with gastric cancer and 16 with esophagogastric junction adenocarcinoma. Most (n = 22) had initial stage usT3Nx disease. Thierry André Patients received 240 mg nivolumab (Opdivo, Bristol Myers Squibb) , an anti-PD-1 antibody, every 2 weeks for a total of six infusions and 1 mg/kg ipilimumab (Yervoy, Bristol Myers Squibb), an anti-CTLA-4 antibody, every 6 weeks for a total of two infusions, followed by radical surgery about 5 weeks after the last nivolumab dose. Those who had Becker tumor regression grade (TRG) of less than 3 received 480 mg adjuvant nivolumab every 4 weeks for a total of nine infusions. Pathologic complete response rate served as the primary endpoint. Key findings Twenty-seven patients (84%) finished all six neoadjuvant treatment cycles and eight experienced grade 3 to grade 4 treatment-related adverse events during that phase of therapy. All but three patients underwent surgery, including two who refused and had complete endoscopic response with tumor-free biopsies and one who experienced metastatic progression. All 29 patients who underwent surgery a median 35 days after last injection had complete resection. Seventeen patients (59%) had pathologic complete response, four had TRG 1b (< 10% residual tumor per tumor bed), one had TRG 2 (10%-50% of residual tumor) and seven had TRG 3 (50% of residual tumor) per local assessment. Twenty-two patients experienced postoperative general complications, including fistula (n = 6) and pancreatitis (n = 3). With median follow-up of 12 months, 30 patients remained recurrence/progression-free, one had metastatic relapse after six treatment cycles and no surgery, and one died without relapse due to a cardiovascular adverse event 3 days after surgery. “NEONIPIGA raises the question of whether the surgery can be delayed or avoided for some patients with localized MSI/dMMR esophagogastric junction or gastric adenocarcinoma if immune checkpoint inhibitors are effective,” André said. Read more about