ONIVYDE® in Combination with 5-FU and Leucovorin Improves Overall Survival in Metastatic Pancreatic Carcinoma

SUMMARY: The FDA on October 22, 2015 approved ONIVYDE® (Irinotecan liposome injection) administered in combination with Fluorouracil (5-FU) and Leucovorin , for the treatment of patients with metastatic adenocarcinoma of the Pancreas, whose disease has progressed following GEMZAR® (Gemcitabine) based therapy. The American Cancer Society estimates that in 2015, close to 49,000 people will be diagnosed with pancreatic cancer in the United States and over 40,000 people will die of the disease. Some important risk factors for Pancreatic cancer include increasing age, obesity, smoking history, genetic predisposition, exposure to certain dyes and chemicals, heavy alcohol use and pancreatitis. The best chance for long term survival is complete surgical resection, although this may not be feasible in a majority of the patients, as they present with advanced disease at the time of diagnosis. Based on the National Cancer Data Base, the 5 year observed survival rate for patients diagnosed with exocrine cancer of the Pancreas is 14% for those with Stage IA disease and 1% for those with Stage IV disease.

ONIVYDE® is a novel nanoliposomal encapsulation of Irinotecan, a topoisomerase 1 inhibitor. It is designed to optimize the delivery of Irinotecan, by extending the duration of circulation of the drug in the body and preferentially activating the drug within the tumor tissues, to achieve higher levels of the active cytotoxic drug metabolite, SN-38. This approach reduces the toxicity of Irinotecan to normal tissues while maintaining or increasing its anti-tumor efficacy.

NAPOLI-1 is an open-label phase III study in which 417 patients with Gemcitabine-refractory metastatic Pancreatic adenocarcinoma were randomly assigned in a 1:1:1 ratio to receive either ONIVYDE® monotherapy, ONIVYDE® plus 5-FluoroUracil (5-FU) and Leucovorin or 5-FU with Leucovorin (control group). Sixty one percent (61%) of patients had cancer in the head of the Pancreas and 68% had liver metastases. Treatment consisted of ONIVYDE® 120 mg/m2 IV over 90 minutes every 3 weeks in Group A, ONIVYDE® 80 mg/m2 IV given over 90 minutes followed by 5-FU 2400 mg/m2 given over 46 hours and racemic Leucovorin 400 mg/m2 IV given over 30 minutes every 2 weeks in Group B and 5-FU 2000 mg/m2 IV given over 24 hours plus racemic Leucovorin 200 mg/m2 IV given over 30 minutes weekly for 4 weeks followed by 2 weeks of rest in Group C (Control group).

Each of the two ONIVYDE® containing groups was compared with the 5FU/Leucovorin control group. The primary study endpoint was Overall Survival and secondary endpoints included Progression Free Survival (PFS) and Overall Response Rate (ORR). The combination of ONIVYDE®, 5-FU and Leucovorin resulted in a median OS of 6.1 months compared with 4.2 months with 5-FU and Leucovorin alone (HR = 0.67; P=0.012). The median PFS was 3.1 months for the ONIVYDE® combination compared with 1.5 months with 5-FU and Leucovorin alone (HR= 0.55; P=0.0001). The ORR was low in both treatment groups (7.7% vs 0.8%). ONIVYDE® montherapy was not superior, compared with 5-FU and Leucovorin and was associated with more side effects compared to the combination regimen. In an expanded, pre-specified analyses, patients who received at least 80% of the target dose in the first 6 weeks experienced an even greater Overall Survival benefit (43% improvement) with ONIVYDE® combination, compared with 5-FU and Leucovorin alone (8.9 months vs 5.1 months, HR=0.57, P=0.011).

The most common grade 3/4 adverse events with ONIVYDE® plus 5-FU and Leucovorin were neutropenia, fatigue, diarrhea and vomiting. The authors concluded that a combination of ONIVYDE® plus 5-FU and Leucovorin significantly improved Overall Survival compared to 5-FU and Leucovorin with manageable toxicities. Expanded analyses of Napoli-1: Phase 3 study of MM-398 (nal-IRI), with or without 5-fluorouracil and leucovorin, versus 5-fluorouracil and leucovorin, in metastatic pancreatic cancer (mPAC) previously treated with gemcitabine-based therapy. Chen L, Von Hoff DD, Li C, et al. J Clin Oncol 33, 2015 (suppl 3; abstr 234)