Nuvelo Inc.‘s experimental blood clot dissolver restores function in patients with blocked catheters faster than existing therapy, the company said on Saturday.

The catheters, known as central venous access devices, are used to deliver chemotherapy, drugs or nutrition to patients. Each year, about five million of the devices are used in the United States and about 25 percent of them become blocked.

Nuvelo’s drug, alfimeprase, is a protein that breaks up the fibrin that holds blood clots together.

A mid-stage trial of 55 patients compared three doses of alfimeprase against the approved dose of Genentech Inc.‘s clot buster Cathflo Activase, which works by converting a protein into a substance that dissolves clots.

The highest dose of alfimeprase produced cumulative blood flow rates of 50 percent 15 minutes after the first dose, 60 percent at two hours, and 80 percent two hours after the second dose. For Cathflo Activase flow rates were zero percent 15 minutes after the first dose, 46 percent at two hours and 62 percent two hours after the second dose.

“This is all about speed,” said Nuvelo’s Chief Executive Ted Love. “This is an opportunity to give a drug more rapidly so the patient can get their chemotherapy and go home.”

No major bleeding events were reported in the trial patients and one patient had a catheter-related infection.

Sunnyvale, California-based Nuvelo plans to launch in the first quarter of next year a pivotal-stage of alfimeprase as a treatment for “leg attack,” in which the peripheral leg artery becomes blocked by a blood clot.

“We believe alfimeprase in “leg attack” and catheter occlusion addresses a worldwide $500 million-plus market opportunity. Additional indications including stroke, heart attack and deep vein thrombosis represent significant upside,” Bank of America analyst Jennifer Chao said in a report on Friday.

The trial results were presented at a meeting of the American Society of Hematology in San Diego.