An Antibody-Drug Conjugate Targeting MUC1-Associated Carbohydrate CA6 Shows Promising Antitumor Activities.

Glycosylation is a complex multienzyme-related process that is frequently deregulated in cancer. Aberrant glycosylation can lead to the generation of novel tumor surface-specific glycotopes that can be targeted by antibodies. Murine DS6 mAb (muDS6) was generated from serous ovary adenocarcinoma immunization. It recognizes CA6, a Mucin-1 (MUC1)-associated sialoglycotope that is highly detected in breast, ovarian, lung, and bladder carcinomas. SAR566658 antibody-drug conjugate (ADC) is a humanized DS6 (huDS6) antibody conjugated through a cleavable linker to the cytotoxic maytansinoid derivative drug, DM4. SAR566658 binds to tumor cells with subnanomolar affinity, allowing good ADC internalization and intracellular delivery of DM4, resulting in tumor cell death (IC50 from 1 to 7.3 nmol/L). SAR566658 showed in vivo antitumor efficacy against CA6-positive human pancreas, cervix, bladder, and ovary tumor xenografts and against three breast patient-derived xenografts. Tumor regression was observed in all tumor models with minimal effective dose correlating with CA6 expression. SAR566658 displayed better efficacy than standard-of-care nontargeted tubulin binders. These data support the development of SAR566658 in patients with CA6-expressing tumors.

Addition of aflibercept to fluorouracil, leucovorin, and irinotecan improves survival in a phase III randomized trial in patients with metastatic colorectal cancer previously treated with an oxaliplatin-based regimen.

PURPOSE: Treatment for metastatic colorectal cancer (mCRC) commonly involves a fluoropyrimidine-based chemotherapy regimen such as infusional fluorouracil, leucovorin, and irinotecan (FOLFIRI) or fluorouracil, leucovorin, and oxaliplatin, often combined with bevacizumab or an epidermal growth factor receptor monoclonal antibody. We studied the effect of adding the novel antiangiogenic agent aflibercept (also known as ziv-aflibercept in the United States) to FOLFIRI in patients with mCRC previously treated with oxaliplatin, including patients who received prior bevacizumab. PATIENTS AND METHODS: Patients were randomly assigned to receive aflibercept (4 mg/kg intravenously; 612 patients) or placebo (614 patients) every 2 weeks in combination with FOLFIRI. Treatment was administered until disease progression or unacceptable toxicity. The primary end point was overall survival. RESULTS: Adding aflibercept to FOLFIRI significantly improved overall survival relative to placebo plus FOLFIRI (hazard ratio [HR], 0.817; 95.34% CI, 0.713 to 0.937; P = .0032) with median survival times of 13.50 versus 12.06 months, respectively. Aflibercept also significantly improved progression-free survival (PFS; HR, 0.758; 95% CI, 0.661 to 0.869; P < .0001), with median PFS times of 6.90 versus 4.67 months, respectively. The effects on overall survival and PFS exhibited a consistent trend across prespecified subgroup analyses, including bevacizumab pretreated patients. Response rate was 19.8% (95% CI, 16.4% to 23.2%) with aflibercept plus FOLFIRI compared with 11.1% (95% CI, 8.5% to 13.8%) with placebo plus FOLFIRI (P = .0001). Adverse effects reported with aflibercept combined with FOLFIRI included the characteristic anti-vascular endothelial growth factor effects and also reflected an increased incidence of some chemotherapy-related toxicities. CONCLUSION: Aflibercept in combination with FOLFIRI conferred a statistically significant survival benefit over FOLFIRI combined with placebo in patients with mCRC previously treated with oxaliplatin.