fb-pixel Skip to main content

FDA approves Merrimack pancreatic cancer drug

Scientist Shawn Carey worked inside the labs at Merrimack Pharmaceuticals in Cambridge earlier this month. Jessica Rinaldi/Globe Staff

Federal regulators on Thursday approved a drug developed by Cambridge-based Merrimack Pharmaceuticals Inc. to treat metasatic pancreatic cancer, one of the few new treatments to be approved in decades for the aggressive and devastating disease.

The drug, which was given the brand name Onivyde, will be used as part of a combination regimen with a two-drug chemotherapy. It was approved for US sale to treat patients with pancreatic cancer that progressed after treatment with a different chemotherapy.

While the new regimen promises to extend patients’ lives for only months, on average, it is still considered a significant advance in a field where there have been few therapeutic options and little hope. Merrimack’s drug was given priority review status, resulting in a six-month Food and Drug Administration evaluation rather than the standard 10 months.


“It’s an important step forward, and it’s one that hopefully we at Merrimack can build on,” chief executive Bob Mulroy said. “Today’s exciting for pancreatic patients and the oncology community. We’ve been working hard for this. For us, it’s just the beginning of a lot more progress we hope to make against all types of solid tumors.”

The drug approval is Merrimack’s first, marking the start of its transition from a research biotech into a full-scale commercial company. Merrimack, with about 350 employees, has hired a sales force of about 50 across the United States and will begin educating pancreatic cancer specialists about Onivyde. The drug will be launched Monday.

Edward Stewart, head of Merrimack’s commercial operations, said the company would charge $11,200 per patient each month for the drug regimen. The cost of the average course of treatment is estimated to total $43,000, based on the life expectancy of patients, he said. About 19,000 pancreatic cancer patients in the United States are eligible for the drug, Stewart said.


“By using the priority review designation for the application for Onivyde, patients will have earlier access to a drug that helps extend survival,” Dr. Richard Pazdur, director of hematology and oncology at the FDA’s Center for Drug Evaluation and Research, said in a statement.

The agency also granted Merrimack an orphan-drug designation for Onivyde, enabling the company to qualify for tax credits and user fee waivers, along with other incentives.

Pancreatic cancer is among the most difficult diseases to treat. It accounts for about 3 percent of all tumors but is the fourth-leading cause of cancer death, with a five-year survival rate of only 7 percent. There will be nearly 49,000 cases diagnosed in the United States this year and more than 40,000 deaths caused by the disease, according to the National Cancer Institute.

Onivyde’s effectiveness was demonstrated in a clinical study involving 417 patients whose tumors had grown after receiving a chemotherapy. Patients treated with Onivyde plus a chemotherapy combining the drugs fluorouracil and leucovorin lived an average of 6.1 months, compared to 4.2 months for those treated only with the chemotherapy, though individual patients taking the three-drug combo lived much longer.

FDA regulators approved the drug with a so-called boxed warning — common for chemotherapies and other cancer drugs — alerting doctors and patients about side effects such as diarrhea and an abnormally low white blood cell count. The drug was approved to be used only in combination with chemotherapy, not by itself.

Onivyde had been known by its company designation, MM-398, as it advanced through clinical trials run by Merrimack, a 15-year-old company founded by scientists from Harvard University and the Massachusetts Institute of Technology.


The company has six other drugs being tested in clinical studies and two more preclinical compounds in its Kendall Square labs.

Analysts have projected that Onivyde eventually could generate annual US sales of about $400 million, and investors have bid up Merrimack shares in recent years in anticipation of a drug approval. But the shares lost $1.30, or 13 percent, to end trading on Thursday at $8.71.

“We had given MM-398 an 85 percent probability of success based on the positive [late-stage] III trial and medical need, but the approval still elicits a sigh of relief,” Eric Criscuolo, life sciences analyst for Mizuho Securities USA Inc. wrote in a note to investors.

FDA officials had been scheduled to make a ruling on Merrimack’s drug application by the end of the week, but its early decision Thursday took some in the industry by surprise.

Robert Weisman can be reached at robert.weisman@globe.com.
Follow him on Twitter @GlobeRobW.

This story was updated at 3:43 p.m. to correct the spelling of Merrimack Pharmaceuticals chief executive Bob Mulroy’s last name.