The phosphatidylserine targeting antibody bavituximab plus pembrolizumab in unresectable hepatocellular carcinoma: a phase 2 trial.

Immune checkpoint inhibitors targeting PD-1/L1 have modest efficacy in hepatocellular carcinoma as single agents. Targeting membranous phosphatidylserine may induce pro-inflammatory and -immune stimulating effects that enhance immunotherapy activity. This hypothesis was tested in a single-arm phase 2 trial evaluating frontline bavituximab, a phosphatidylserine targeting antibody, plus pembrolizumab (anti-PD-1) in patients with unresectable hepatocellular carcinoma (NCT03519997). The primary endpoint was investigator-assessed objective response rate among evaluable patients, and secondary end points included progression-free survival, incidence of adverse events, overall survival, and duration of response. Among 28 evaluable patients, the confirmed response rate was 32.1%, which met the pre-specified endpoint, and the median progression-free survival was 6.3 months (95% CI, 1.3-11.3 months). Treatment related-adverse events of any grade occurred in 45.7% of patients, with grade 3 or greater adverse events in 14.3% of patients. Adverse events of any cause were observed in 33 patients (94.3%), with grade 3 or greater adverse events in 11 patients (31.4%). Prespecified exploratory analyses of baseline tumor specimens showed that a depletion of B cells, and the presence of fibrotic tissue and expression of immune checkpoints in stroma was associated with tumor response. These results suggest that targeting phosphatidylserine may lead to synergistic effects with PD-1 blockade without increasing toxicity rates, and future studies on this therapeutic strategy may be guided by biomarkers characterizing the pre-treatment tumor microenvironment.

A Propensity Score Analysis of Chemotherapy Use in Patients With Resectable Gallbladder Cancer.

Importance: Gallbladder cancer is uncommon but highly fatal. Surgery remains the only potentially curative treatment for localized or locoregionally advanced gallbladder cancer. The rate of use of neoadjuvant and adjuvant chemotherapy in resectable gallbladder cancer is unknown. Objective: To assess factors associated with the use of neoadjuvant and adjuvant chemotherapy in patients with resectable gallbladder cancer and survival outcomes. Design, Setting, and Participants: The National Cancer Database was used to identify 6391 adults who underwent definitive surgical resection for gallbladder cancers between January 1, 2004, and January 1, 2016. Data analysis was performed from January 15 to February 15, 2020. Patients with localized or locoregionally advanced gallbladder cancers (ie, categories cTx-cT4, cN0-2, and cM0) were categorized as receiving neoadjuvant chemotherapy, adjuvant chemotherapy, or surgery alone. Categorical variables were compared using the χ2 test, with 1:3 nearest-neighbor propensity score matching based on neoadjuvant chemotherapy. Survival outcomes between groups were compared using Kaplan-Meier and Cox proportional hazards regression analyses. Main Outcomes and Measures: The use and survival outcomes of adjuvant and neoadjuvant chemotherapy. Results: Of 6391 patients who underwent definitive surgery for gallbladder cancer, 4559 were women (71.3%); median age was 68 (IQR, 59-77) years. A total of 3145 patients (49.2%) received adjuvant chemotherapy, 3145 patients (49.2%) underwent surgery without chemotherapy, and 101 patients (1.6%) received neoadjuvant chemotherapy. Neoadjuvant chemotherapy use was associated with treatment at an academic facility (61 patients [60%] vs 38 patients [38%] treated in a nonacademic facility; P < .001) and in those with private insurance (65 patients [65%] vs 11 patients [11%] with Medicaid insurance; P < .001). Surgery alone was frequently used in older patients (median age, 72 [IQR, 63-81] years vs 59 [IQR, 52-66] years in patients with neoadjuvant chemotherapy; P < .001), those with Medicare insurance (1925 patients [57%] vs 1438 patients [43%] with adjuvant chemotherapy; P < .001), and patients with a higher comorbidity index score (326 patients [62%] vs 197 patients [38%] with adjuvant chemotherapy; P < .001). Adjuvant or neoadjuvant chemotherapy was used more frequently than surgery in patients with node-positive cancer (1482 [67.2%] vs 53 [65.4%] vs 912 [49.7%]). On propensity score matching analysis, adjuvant chemotherapy was associated with longer survival than surgery alone (22 vs 18 months, hazard ratio [HR], 0.78; 95% CI, 0.63-0.96); survival with neoadjuvant chemotherapy was not statistically significant compared with surgery alone and adjuvant chemotherapy groups (27 months, HR, 0.78; 95% CI, 0.58-1.04). However, in patients with node-positive gallbladder cancer, neoadjuvant therapy was associated with longer median overall survival (30 months [95% CI, 24-36 months] vs 14 months [95% CI, 11-17] in patients with surgery alone; P = .002). Conclusions and Relevance: In this cohort study, use of adjuvant and neoadjuvant chemotherapy was low in patients with surgically resected gallbladder cancers. Chemotherapy was used more frequently than surgery in lymph node-positive disease compared with lymph node-negative disease. Adjuvant chemotherapy was associated with a survival advantage in resectable gallbladder cancer, and neoadjuvant chemotherapy was associated with increased survival in node-positive gallbladder cancers. These findings suggest that adjuvant chemotherapy and neoadjuvant chemotherapy should be considered in treatment of gallbladder cancer.