IRVINE, Calif. (

TheStreet

) --

Spectrum Pharmaceuticals

(SPPI) - Get Report

was granted approval by U.S. regulators to expand the use of its non-Hodgkin's lymphoma (NHL) drug Zevalin, the company announced Friday.

The U.S. Food and Drug Administration's full approval allows Spectrum to market Zevalin as a first-line consolidation therapy for NHL patients -- a move that is expected to significantly widen the number of patients treated with the drug and breathe new life into moribund sales.

Before Friday, Zevalin's approval only covered NHL patients whose tumors continued to grow despite previous treatments. First approved in 2001, Zevalin saw sales of just $11 million last year.

"We're really pleased with the new label. We got everything that we wanted from the FDA and more," said Spectrum CEO Rajesh Shrotriya in a telephone call Thursday night, soon after the FDA's letter arrived in the company's office.

Zevalin today garners about 12% market share in the approximate 6,000 U.S. NHL patients treated with third-line drugs. The new FDA approval expands Zevalin's NHL patient pool to 46,000 patients, according to Spectrum.

Shrotriya declined to give specific sales guidance for Zevalin, but he has stated in the past that expansion into first-line NHL patients could grow the drug to $100 million-plus sales annually.

With FDA approval checked off his to-do list, Shrotriya says the company plans on expanding its Zevalin sales force with a goal of re-launching the drug later this year.

"We're planning to have a big presence at the ASH meeting, and we're lining up experts in the field who want to speak on Zevalin's behalf," said Shrotriya.

ASH refers to the American Society of Hematology annual meeting, the largest gathering of doctors and experts involved in research and treatment of blood-related cancers and disease held every December.

Zevalin is a monoclonal antibody that seeks out and attaches itself to cancer cells. But unlike other such drugs, Zevalin carries a radioactive payload designed to kill the cancer cells while leaving neighboring healthy cells intact. Zevalin was the first in a new class of "radio-immunotherapies" approved by the FDA. Since its approval, only one other radio-immunotherapy drug has made it to the market --

GlaxoSmithKline's

(GSK) - Get Report

Bexxar.

Unfortunately the cutting-edge technology behind Zevalin turned out to be a major hindrance commercially. Because it's a radioactive compound, doctors and patients must go through a long checklist of precautions and pretreatment steps before Zevalin can be administered. Plus, the drug has never enjoyed favorable insurance reimbursement status, so oftentimes, doctors actually lose money when prescribing Zevalin to their patients.

Spectrum gained 100% U.S. rights to Zevalin earlier this year and is continuing efforts begun by the drug's previous owner,

Cell Therapeutics

(CTIC) - Get Report

, and starting new initiatives of its own designed to improve sales performance.

The expanded label for first-line NHL treatment will help, as will new, more favorable Medicare reimbursement rules for Zevalin that Shrotriya hopes to have in place in November.

"Our goal for Zevalin is to reach more patients," he said.

Spectrum shares were 0.7% to $8.82 in Friday trading.

-- Reported by Adam Feuerstein in Boston

Adam Feuerstein writes regularly for TheStreet.com. In keeping with TSC's editorial policy, he doesn't own or short individual stocks, although he owns stock in TheStreet.com. He also doesn't invest in hedge funds or other private investment partnerships. Feuerstein appreciates your feedback;

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