A phase II clinical trial of toripalimab in advanced solid tumors with polymerase epsilon/polymerase delta (POLE/POLD1) mutation.

Patients carrying mutations in polymerase epsilon/polymerase delta have shown positive responses to immune checkpoint inhibitors. Yet, prospective trials exploring the efficacy in those with polymerase epsilon/polymerase delta mutations are still lacking. A phase II clinical trial was initiated to evaluate the efficacy of toripalimab, a humanized IgG4K monoclonal antibody to human PD-1, in patients with advanced solid tumors with unselected polymerase epsilon/polymerase delta mutations but without microsatellite instability-high. A total of 15 patients were enrolled, 14 of whom were assessed for treatment efficacy. There was a 21.4% overall response rate, with a disease control rate of 57.1%. The median overall survival and median progression-free survival were 17.9 (95% CI 13.5-not reach) months and 2.5 (95% CI 1.4-not reach) months, respectively. For patients with exonuclease domain mutations, the objective response rate was 66.7% (2/3), with a disease control rate of 66.7% (2/3). For those with non-exonuclease domain mutations, the rates were 9.1% (1/11) and 54.5% (6/11), respectively. Notably, patients with PBRM1 gene mutations exhibited a high response rate to toripalimab at 75.0% (3/4). This study showed that neither the exonuclease domain mutations nor non-exonuclease domain mutations could fully predict the efficacy of immunotherapy, urging the need for more investigations to clarify potential immune sensitization differences within polymerase epsilon/polymerase delta mutation variants.

A Randomized, Open-Label, Multicenter, Phase 3 Study of High-Dose Vitamin C Plus FOLFOX ± Bevacizumab versus FOLFOX ± Bevacizumab in Unresectable Untreated Metastatic Colorectal Cancer (VITALITY Study).

PURPOSE: To compare the efficacy and safety of high-dose vitamin C plus FOLFOX ± bevacizumab versus FOLFOX ± bevacizumab as first-line treatment in patients with metastatic colorectal cancer (mCRC). PATIENTS AND METHODS: Between 2017 and 2019, histologically confirmed patients with mCRC (n = 442) with normal glucose-6-phosphate dehydrogenase status and no prior treatment for metastatic disease were randomized (1:1) into a control (FOLFOX ± bevacizumab) and an experimental [high-dose vitamin C (1.5 g/kg/d, intravenously for 3 hours from D1 to D3) plus FOLFOX ± bevacizumab] group. Randomization was based on the primary tumor location and bevacizumab prescription. RESULTS: The progression-free survival (PFS) of the experimental group was not superior to the control group [median PFS, 8.6 vs. 8.3 months; HR, 0.86; 95% confidence interval (CI), 0.70-1.05; P = 0.1]. The objective response rate (ORR) and overall survival (OS) of the experimental and control groups were similar (ORR, 44.3% vs. 42.1%; P = 0.9; median OS, 20.7 vs. 19.7 months; P = 0.7). Grade 3 or higher treatment-related adverse events occurred in 33.5% and 30.3% of patients in the experimental and control groups, respectively. In prespecified subgroup analyses, patients with RAS mutation had significantly longer PFS (median PFS, 9.2 vs. 7.8 months; HR, 0.67; 95% CI, 0.50-0.91; P = 0.01) with vitamin C added to chemotherapy than with chemotherapy only. CONCLUSIONS: High-dose vitamin C plus chemotherapy failed to show superior PFS compared with chemotherapy in patients with mCRC as first-line treatment but may be beneficial in patients with mCRC harboring RAS mutation.

Comprehensive profiling of 1015 patients' exomes reveals genomic-clinical associations in colorectal cancer.

The genetic basis of colorectal cancer (CRC) and its clinical associations remain poorly understood due to limited samples or targeted genes in current studies. Here, we perform ultradeep whole-exome sequencing on 1015 patients with CRC as part of the ChangKang Project. We identify 46 high-confident significantly mutated genes, 8 of which mutate in 14.9% of patients: LYST, DAPK1, CR2, KIF16B, NPIPB15, SYTL2, ZNF91, and KIAA0586. With an unsupervised clustering algorithm, we propose a subtyping strategy that classisfies CRC patients into four genomic subtypes with distinct clinical characteristics, including hypermutated, chromosome instability with high risk, chromosome instability with low risk, and genome stability. Analysis of immunogenicity uncover the association of immunogenicity reduction with genomic subtypes and poor prognosis in CRC. Moreover, we find that mitochondrial DNA copy number is an independent factor for predicting the survival outcome of CRCs. Overall, our results provide CRC-related molecular features for clinical practice and a valuable resource for translational research.

Anti-PD-1 antibody SHR-1210 plus apatinib for metastatic colorectal cancer: a prospective, single-arm, open-label, phase II trial.

In the REGONIVO study, regorafenib combined with nivolumab was effective in the treatment of microsatellite stable (MSS) metastatic colorectal cancer (mCRC), which indicated anti-angiogenic drugs may enhance the efficacy of immune checkpoint inhibitors. Therefore, we designed a single-arm, single-center, open-label, phase II trial to determine the toxicity and efficacy of SHR-1210 (an anti-PD-1 antibody) plus apatinib in MSS mCRC. The sample size was estimated using a Simon Optimum two-stage design. 10 patients were included at the first stage and if one effective patient observed, an additional 19 patients would be added. Patients with MSS mCRC who refractory to second-line treatment or intolerant to standard treatment were given SHR-1210 200 mg every 2 weeks and apatinib 250-375 mg once daily until unacceptable toxicity or disease progression occurred. In our study, the objective response rate was 0% and the disease control rate was 22.2%. The median progression-free survival was 1.83 months (95% confidence interval (CI) 1.80-1.86 months), and the median overall survival was 7.80 months (95% CI 0-17.07). Treatment-related adverse events (AEs) occurred in all patients (100%). The most common treatment-related AEs were hypertension and proteinuria (70% each). Grade 3 AEs were observed in nine patients (9/10, 90%), and the commonest was hypertension (30%). In conclusion, SHR-1210 combined with apatinib has failed to improve the efficacy of treatment of MSS mCRC, and the intolerable toxicity may be the leading cause.