The US Food and Drug Administration (FDA) has approved, with reservations, the new pancreatic cancer drug Onivyde manufactured by US drugmaker Merrimack for use in combination with leucovorin and fluorouracil.

The drug combination is being touted as a chemotherapeutic option for patients with advanced pancreatic cancer who are no longer responsive to gemcitabine-based treatments.

Merrimack CEO Robert Mulroy called the FDA approval “a pivotal milestone in our company's history, representing years of hard work and commitment to our mission of engineering new treatment options for cancer patients in need.”

Effectiveness of the treatment was evaluated in a randomized, three-arm study on more than 400 patients with metastatic pancreatic cancer. Results showed that patients treated with a combination of Onivyde and fluorouracil/leucovorin had delayed tumor growth compared with other participants in the trial who were treated with only fluorouracil/leucovorin or Onivyde alone.

Scientists said the results were encouraging because pancreatic cancer, due to the difficulty of diagnosing it early, is one of the deadliest cancers, and treatment options up to now have been limited.

The caveat is that, like most chemotherapeutic drugs, Onivyde comes with many side effects. Based on patient evaluation, the most common are said to include diarrhea, nausea and vomiting, fatigue, anorexia, stomatitis, immunosupression and fever. There is also a risk for decreased kidney function, sepsis and death, which is why the FDA has required labels with boxed warnings to alert prescribers to the risks for diarrhea and severe neutropenia.

Onivyde is also not meant to be used as a singular chemotherapeutic agent.