Evanston-based Northfield Laboratories Inc. said more patients who were on its experimental blood substitute died within 30 days after transfusions than those who didn't get the product. Shares fell by almost half in early trading.
The product, PolyHeme, is in the last of three stages of tests generally required for U.S. regulatory approval, the company said today in a statement on Business Wire. Northfield hasn't submitted its blood substitute to the Food and Drug Administration for review.
Northfield's experimental product, a solution of chemically modified human hemoglobin, could compete with a cow-derived blood substitute being tested by Biopure Corp. The FDA last year rejected Biopure's proposed trials for its product, Hemopure, because of ethical concerns that patients wouldn't be able to give informed consent to receive it.
The shares of Northfield fell 43 percent to $2.40 at 9:01 a.m. in early Nasdaq stock market composite trading.
"We continue to believe there is a potential benefit to using PolyHeme in patients with delayed access to blood," said Steven Gould, chairman and chief executive officer, in the statement.
The Northfield study compared survival rates of trauma patients who received PolyHeme at the accident scene and in ambulances to those who got donated blood after arrival at the hospital. PolyHeme is designed to offer an alternative treatment when donated blood isn't immediately available.
More died
More patients given PolyHeme died, compared with the control group. In one comparison, 11.1 percent of the 279 patients given PolyHeme died, versus 9.1 percent of the 307 people who didn't get the blood substitute.
Serious adverse events, such as shock, pneumonia and respiratory failure, occurred in 40 percent of patients who received PolyHeme, compared with 35 percent for those who didn't.
A spokesman for Northfield didn't immediately return calls or emails seeking comment on the study.
The U.S. Navy last year asked the FDA to clear tests of Biopure's blood substitute in a trial that could include civilian trauma patients. The Navy wanted to see if Hemopure can prevent trauma victims from bleeding to death in an ambulance before they reach the hospital.
Hemopure is a purified and processed form of hemoglobin, the carrier of oxygen in the blood, extracted from cows' blood cells. Researchers have long tried to find a substitute for human blood to address severe blood loss, which accounts for a third of trauma deaths. Paramedics usually substitute saline solution for blood, which must be type-matched and kept cold.
