Ducreux, Michel

Pancreatic ductal adenocarcinoma (PDAC) is the most common type of pancreatic cancer, and it is a disease of dismal prognosis. While immunotherapy has revolutionized the treatment of various solid tumors, it has achieved little success in PDAC. Hypoxia within the stroma-rich tumor microenvironment is associated with resistance to therapies and promotes angiogenesis, giving rise to a chaotic and leaky vasculature that is inefficient at shuttling oxygen and nutrients. Hypoxia and its downstream effectors have been implicated in immune resistance and could be contributing to the lack of response to immunotherapy experienced by patients with PDAC. Paradoxically, increasing evidence has shown hypoxia to augment genomic instability and mutagenesis in cancer, suggesting that hypoxic tumor cells could have increased production of neoantigens that can potentially enable their clearance by cytotoxic immune cells. Strategies aimed at relieving this condition have been on the rise, and one such approach opts for normalizing the tumor vasculature to reverse hypoxia and its downstream support of tumor pathogenesis. An important consideration for the successful implementation of such strategies in the clinic is that not all PDACs are equally hypoxic, therefore hypoxia-detection approaches should be integrated to enable optimal patient selection for achieving improved patient outcomes.

4023 Background: Metastatic pancreatic cancer (mPC) remains a deadly disease with very limited treatment options. FFX is a standard first-line therapy for mPC with a median overall survival (mOS) of 11.1 months. CPI-613 is a stable intermediate of a lipoate analog that inhibits pyruvate dehydrogenase and α-ketoglutarate dehydrogenase enzymes of the tricarboxylic cycle preferentially within the mitochondria of cancer cells. In a phase I study, CPI-613+mFFX was safe and exhibited promising signal of efficacy. Methods: A global, randomized phase 3 trial was conducted across 73 sites to investigate the efficacy and safety of CPI-613 in combination with mFFX compared to standard dose FFX in treatment-naïve patients with mPC. Treatment was administered in 2-weekly cycles until progression or intolerable toxicity. In the experimental arm, CPI-613 at 500 mg/m2 was given intravenously on days 1 and 3. The doses of irinotecan, oxaliplatin, and 5-fluorouracil in the experimental arm were 65 mg/m2, 140 mg/m2, and 2,400 mg/2, respectively. Primary endpoint was OS. Secondary endpoints were progression-free survival (PFS), overall response rate (ORR), duration of response, pharmacokinetics, patient reported outcomes and safety. Results: 528 patients were randomly assigned (266 in test and 262 in control arm). There were 362 deaths, with a mOS of 11.1 months for CPI-613+mFFX vs. 11.7 months for FFX [hazard ratio (HR), 0.95; 95% CI, 0.77 to 1.18; P = 0.655]; mPFS was 7.8 months vs. 8.0 months respectively [HR, 0.99; 95% CI, 0.76 to 1.29; P = 0.94]; ORR was 39% in the test arm vs. 34% in the control arm [ORR ratio, 1.23 (95% CI, 0.86 to 1.75)]. Grade ≥ 3 treatment-emergent adverse events with ≥ 10% frequency in CPI-613 plus mFFX vs. FFX arm were diarrhea (11.2% vs. 19.6%), hypokalemia (13.1% vs. 14.9%), anemia (13.9% vs. 13.6%), neutropenia (11.2% vs. 14.0%), thrombocytopenia (11.6% vs. 13.6%) and fatigue (10.8% vs. 11.5%). Conclusions: The addition of CPI-613 to mFFX failed to show significant improvements of ORR, PFS or OS. The mFFX in the test arm that had the lowest prospectively tested doses of FFX was without compromise on PFS or OS and may be considered as a reference for future FFX administration. Clinical trial information: NCT03504423.