Randall, Leslie M.

PURPOSE In patients with high-grade ovarian cancer, predictors of bevacizumab efficacy in first-line setting are needed. In the ICON-7 trial, a poor tumor intrinsic chemosensitivity (defined by unfavorable modeled cancer antigen-125 [CA-125] ELIMination rate constant K [KELIM] score) was a predictive biomarker. Only the patients with high-risk disease (suboptimally resected stage III, or stage IV) exhibiting unfavorable KELIM score < 1.0 had overall survival (OS) benefit from bevacizumab (median: 29.7 v 20.6 months; hazard ratio [HR], 0.78). An external validation study in the GOG-0218 trial was performed. METHODS In GOG-0218, 1,873 patients were treated with carboplatin-paclitaxel ± concurrent-maintenance bevacizumab/placebo. Patient KELIM values were calculated with CA-125 kinetics during the first 100 chemotherapy days by the Lyon University team. The association between KELIM score (favorable ≥ 1.0, or unfavorable < 1.0) and bevacizumab benefit for progression-free survival (PFS)/OS was independently assessed by NGR-GOG using univariate/multivariate analyses. RESULTS KELIM was assessable in 1,662 patients with ≥ 3 CA-125 available values. An unfavorable KELIM score was associated with bevacizumab benefit compared with placebo (PFS: HR, 0.70; 95% CI, 0.59 to 0.82; OS: HR, 0.87; 95% CI, 0.73 to 1.03), whereas a favorable KELIM was not (PFS: HR, 0.96; 95% CI, 0.79 to 1.17; OS: HR, 1.11; 95% CI, 0.89 to 1.39). The highest benefit was observed in patients with a high-risk disease exhibiting unfavorable KELIM, for PFS (median: 9.1 v 5.6 months; HR, 0.64; 95% CI, 0.53 to 0.78), and for OS (median: 35.1 v 29.1 months; HR, 0.79; 95% CI, 0.65 to 0.97). CONCLUSION This GOG-0218 trial investigation validates ICON-7 findings about the association between poor tumor chemosensitivity and benefit from concurrent-maintenance bevacizumab, suggesting that bevacizumab may mainly be effective in patients with poorly chemosensitive disease. Bevacizumab may be prioritized in patients with a high-risk and poorly chemosensitive disease to improve their PFS/OS (patient KELIM score calculator available on the Biomarker Kinetics website).

PURPOSE The adjunctive use of intraoperative molecular imaging (IMI) is gaining acceptance as a potential means to improve outcomes for surgical resection of targetable tumors. This confirmatory study examined the use of pafolacianine for real-time detection of folate receptor–positive ovarian cancer. METHODS This phase III, open-label, 11-center study included subjects with known or suspected ovarian cancer, scheduled to undergo cytoreductive surgery. The objectives were to confirm safety and efficacy of pafolacianine (0.025 mg/kg IV), given ≥ 1 hour before intraoperative near-infrared imaging to detect macroscopic lesions not detected by palpation and normal white light. RESULTS From March 2018 through April 2020, 150 patients received a single infusion of pafolacianine (safety analysis set); 109 patients with folate receptor–positive ovarian cancer comprised the full analysis set for efficacy. In 33.0% of patients (95% CI, 24.3 to 42.7; P < .001), pafolacianine with near-infrared imaging identified additional cancer on tissue not planned for resection and not detected by white light assessment and palpation, exceeding the prespecified threshold of 10%. Among patients who underwent interval debulking surgery, the rate was 39.7% (95% CI, 27.0 to 53.4; P < .001). The sensitivity to detect ovarian cancer was 83%, and the patient false-positive rate was 24.8%. Investigators reported achieving complete R0 resection in 62.4% (68 of 109) of patients. Drug-related adverse events were reported by 30% of patients (45 of 150) and most commonly included nausea, vomiting, and abdominal pain. No drug-related serious adverse events or deaths were reported. CONCLUSION This phase III study of pafolacianine met its primary efficacy end point, identifying additional cancers not otherwise identified or planned for resection. Pafolacianine may offer an important real-time adjunct to current surgical approaches for ovarian cancer.

5553 Background: In patients with high-grade ovarian cancer in first-line setting, predictive factors of bevacizumab efficacy are needed, for selecting patients. In ICON-7 trial, a poor tumor intrisic chemosensitivity (defined by unfavorable modeled CA-125 kinetic ELIMination rate constant KELIM) was a predictive biomarker. Among patients with high-risk diseases, only those with unfavorable KELIM had survival benefit from bevacizumab (mOS: 29.7 vs 20.6 months, HR = 0.78)(Colomban. JNCI CS 2020). The objective was to perform an external validation in GOG-0218 trial (NCT00262847). Methods: In GOG-0218, 1,873 patients were treated with carboplatin-paclitaxel +/- concurrent bevacizumab/placebo followed by a 15 month maintenance. Patient KELIM values were estimated with longitudinal CA-125 kinetics during the first 100 chemotherapy days. The association between KELIM score (categorized as favorable ≥ 1, or unfavorable < 1) and efficacy of bevacizumab (bevacizumab-concurrent + maintenance, vs placebo) for PFS and OS was assessed using univariate/multivariate analyses, in a Training set with 2/3 patients managed the investigators, and then a Validation set with all patients, managed by NGR-GOG. Results: KELIM was assessable in 1,662 patients with ≥ 3 CA-125 available values. In both sets, the patients with unfavorable KELIM derived benefit from bevacizumab compared to placebo (Training: PFS, HR = 0.65 [0.54-0.80]; OS, HR = 0.80 [0.65-0.99]; Validation: PFS, HR = 0.69 [0.59-0.82]; OS, HR = 0.87 [0.73-1.03]), whilst those with favorable KELIM had no benefit from bevacizumab (Training: PFS, HR = 0.96 [0.75-1.23]; OS, HR = 1.05 [0.80-1.37]; Validation, PFS, HR = 0.96 [0.79-1.17]; OS HR = 1.11 [0.89-1.84]). The highest benefit was observed in patients with high-risk diseases (stage IV or sub-optimally resected stage III) characterized by unfavorable KELIM, for PFS (Learning (n = 276): mPFS: 9.0 vs 5.2 months, HR = 0.61 [0.48-0.78]; Validation (n = 433): mPFS: 9.1 vs 5.6 months, HR = 0.64 [0.53-0.78]), and for OS (Learning (n = 278): mOS: 38.9 vs 27.9 months, HR = 0.72 [0.56-0.93], Validation set (n = 438): mOS: 35.1 vs 29.1 months, HR = 0.79 [0.65-0.97]). Conclusions: This validation analysis of GOG-0218 trial confirms the outcomes of ICON-7 trial about the association between poor tumor chemosensitivity and benefit from concurrent + maintenance bevacizumab, suggesting that bevacizumab is mainly effective in patients with poorly chemosensitive diseases. No benefit was found in patients with favorable KELIM. The patients who derived the highest benefit from bevacizumab in PFS and OS (OS absolute benefit ̃ 6 to 9 months) were those with high-risk diseases (stage IV, or incompletely resected stage III) associated with an unfavorable KELIM score (calculator on https://www.biomarker-kinetics.org/CA-125).

5503 Background: Pafolacianine sodium is under investigation as an adjunct to visual inspection and palpation by providing intra-operative imaging of folate receptor positive (FR+) ovarian cancer. Since complete resection (R0) is the strongest predictor of overall survival, methods to enhance detection of lesions are expected to benefit patient outcomes. Methods: For this phase 3, randomized, multicenter, single dose, open-label pivotal trial (NCT03180307), patients with ovarian cancer who were scheduled to undergo cytoreductive surgery were recruited from 11 sites in the US and Netherlands from March 2018 through April 2020. The study objectives were to confirm efficacy and safety of pafolacianine sodium (0.025 mg/kg i.v., ≥1 h prior to imaging) in combination with intraoperative near-infrared fluorescence (NIRF) imaging to detect additional lesions not detected by palpation and normal white light alone. Results: Pafolacianine sodium was administered to 150 total patients (safety analysis set); 109 patients comprised the full analysis set for efficacy analyses. Patients had primarily serous adenocarcinoma (n = 72; 68.6%) and advanced stage disease (n = 83; 76.1%). In 33% of patients (36 of 109), NIRF imaging with pafolacianine sodium identified additional lesions that were not planned for resection and were not detected by normal white light and palpation ( P < 0.001, 95% CI [0.243, 0.427]). Among patients who underwent interval debulking surgery, the rate was higher, at 39.7% of patients (23 of 58; 95% CI [0.270, 0.534]). At the individual lesion level, the accuracy of pafolacianine sodium with NIRF to detect ovarian cancer is reflected by sensitivity of 83% (95% CI [73.9, 89.4]) and a false positive rate of 32.7% (95% CI [25.6, 40.7]). Investigators reported achieving complete resection (R0) in 62.4% (68 of 109) of patients. Drug-related adverse events (AEs) were reported by 30% of patients (45 out of 150). The most frequently reported drug-related AEs were nausea (18.0%), vomiting (5.3%), and abdominal pain (4.7%). Infusion reactions at the time of the procedure were mostly (96%) mild or moderate in severity; 89% resolved within 24 hours of onset. No drug-related serious AEs or deaths were reported. Conclusions: This phase 3 trial of pafolacianine sodium with NIRF imaging met its primary endpoint, intraoperatively identifying additional cancer not planned for resection in a statistically significant number of patients. Therefore, pafolacianine sodium may offer a novel real-time adjunct to current surgical imaging practice in ovarian cancer surgery. Clinical trial information: NCT03180307.