The for metastatic pancreatic cancer in combination with fluorouracil (Adrucil) and leucovorin in patients who have already received gemcitabine-based chemotherapy.
The new formulation, which encapsulates conventional irinotecan in nanoparticle liposomes in an effort to improve the pharmacokinetics and tolerability, had been given priority review and orphan drug status in this setting.
Irinotecan hydrochloride (Camptosar) has been approved for use with fluorouracil and leucovorin in the so-called . The liposomal formulation had mixed results in advanced gastric cancer.
The approval for metastatic pancreatic cancer was based on a randomized, open-label study showing mean overall survival of 6.1 months on liposomal irinotecan plus fluorouracil/leucovorin, compared to 4.2 months with fluorouracil/leucovorin alone. The combination also increased the time to progression, with an average of 3.1 months compared to 1.5 months, respectively.
Liposomal irinotecan alone was no better than fluorouracil/leucovorin alone in the trial, and the drug was not approved for single-agent use in metastatic pancreatic cancer.
The most common side effects of liposomal irinotecan were diarrhea, fatigue, vomiting, nausea, decreased appetite, stomatitis, and fever.
The label has a boxed warning about the risks of severe neutropenia and diarrhea. "Death due to sepsis following neutropenia has been reported in patients treated with Onivyde," the FDA press release noted.
Liposomal irinotecan is marketed by Merrimack Pharmaceuticals, of Cambridge, Mass.