Soon‐Shiong, Patrick

Introduction Lynch syndrome (LS) is a hereditary cancer syndrome that increases risk for colorectal and other cancers. We hypothesize that vaccines against tumor-associated antigens CEA, MUC1, and brachyury, simultaneously delivered in an adenovirus serotype-5 vector (Tri-Ad5) combined with the immune-enhancing IL-15 receptor superagonist nogapendekin-alfa-inbakicept (NAI) will reduce the incidence of colorectal neoplasms in LS carriers. Methods In this ongoing phase IIB double-blind placebo-controlled trial, two open-label safety phases (SPs) assessed safety of Tri-Ad5 alone (SP1, n=10) and with added NAI (SP2, n=10). A randomized controlled trial (RCT) follows the SPs. After baseline colonoscopy, vaccine dosing occurs at weeks 0, 4 and 8; Tri-Ad5 alone in SP1 and Tri-Ad5 plus NAI in SP2, with identical boosters at Week 52. The RCT phase participants (n=138) were randomized to receive Tri-Ad5 plus NAI or placebo. All participants complete colonoscopy at Weeks 52 and 104 for assessment of the primary endpoint: cumulative colorectal neoplasm incidence. Secondary endpoints include safety, tolerability, and immunogenicity. Results All 20 SP participants (median age 57.5 (range 42–75), 70% female, 15% minority) received all prime and booster series. SP1 participants reported 139 adverse events (AEs) and SP2 participants reported 178. AEs were predominantly grade 1; no treatment-related serious adverse events (SAEs) occurred. The most common treatment-related AEs were reactogenic events including grade 3 rash (without skin necrosis or breakdown) at NAI injection site (100% of SP2 participants). The RCT phase (n=138) recently completed accrual. Discussion In LS carriers without active cancer, the combination of Tri-Ad5 + NAI was well-tolerated; the RCT phase is ongoing. Clinical Trial Registration https://clinicaltrials.gov/study/ , identifier NCT05419011.

Purpose The trial objectives were to identify the maximum-tolerated dose (MTD) of first-line gemcitabine plus nab-paclitaxel in metastatic pancreatic adenocarcinoma and to provide efficacy and safety data. Additional objectives were to evaluate positron emission tomography (PET) scan response, secreted protein acidic and rich in cysteine (SPARC), and CA19-9 levels in relation to efficacy. Subsequent preclinical studies investigated the changes involving the pancreatic stroma and drug uptake. Patients and Methods Patients with previously untreated advanced pancreatic cancer were treated with 100, 125, or 150 mg/m 2 nab-paclitaxel followed by gemcitabine 1,000 mg/m 2 on days 1, 8, and 15 every 28 days. In the preclinical study, mice were implanted with human pancreatic cancers and treated with study agents. Results A total of 20, 44, and three patients received nab-paclitaxel at 100, 125, and 150 mg/m 2 , respectively. The MTD was 1,000 mg/m 2 of gemcitabine plus 125 mg/m 2 of nab-paclitaxel once a week for 3 weeks, every 28 days. Dose-limiting toxicities were sepsis and neutropenia. At the MTD, the response rate was 48%, with 12.2 median months of overall survival (OS) and 48% 1-year survival. Improved OS was observed in patients who had a complete metabolic response on [ 18 F]fluorodeoxyglucose PET. Decreases in CA19-9 levels were correlated with increased response rate, progression-free survival, and OS. SPARC in the stroma, but not in the tumor, was correlated with improved survival. In mice with human pancreatic cancer xenografts, nab-paclitaxel alone and in combination with gemcitabine depleted the desmoplastic stroma. The intratumoral concentration of gemcitabine was increased by 2.8-fold in mice receiving nab-paclitaxel plus gemcitabine versus those receiving gemcitabine alone. Conclusion The regimen of nab-paclitaxel plus gemcitabine has tolerable adverse effects with substantial antitumor activity, warranting phase III evaluation.