NeXstar Pharmaceuticals Inc. got approval of its liposome product inSweden on Monday, three days before its second attempt at showingan FDA advisory committee that the drug is as efficacious asconventional therapy with fewer side effects.

NeXstar, of Boulder, Colo., said the Swedish approval ofDaunoXome marked the first liposomal anticancer agent to beapproved by any regulatory agency.

DaunoXome, a liposomal formulation of daunorubicin, was approvedin Sweden as a primary therapy for Kaposi's sarcoma (KS). It will besold by Stockholm-based Swedish Orphan AB, which already isselling NeXstar's antifungal liposome product, Ambisome, inScandinavia.

NeXstar filed for approval in Sweden, France and the U.K. last June.Sweden now will act as rapporteur for the product in other Europeancountries. NeXstar used European Phase II trial data, augmented byPhase III U.S. data, in its submission in Sweden.

That Phase III data will be presented for the first time on Thursday tothe FDA's Oncologic Drugs Advisory Committee (ODAC), whichvoted unanimously in June 1993 against recommending approval ofthe drug for KS.

The committee and the company (which then was Vestar Inc.) haddifferent conclusions about analyses of data that came from a PhaseII trial. So Vestar, which merged with NeXagen Inc. last year to formNeXstar, continued a Phase III controlled trial comparingDaunoXome with a standard three-drug chemotherapy regimen(ABV). NeXstar used the Phase III data to file an amended new drugapplication in January.

While not releasing specific data, Joseph Alper, NeXstar's director ofcorporate communications, said, "We think there was therapeuticvalue. The data shows the efficacy of this drug compared to standardtreatment was comparable and the side-effect profile is significantlybetter."

Alper said specific advantages seen in the DaunoXome group relatedto the incidence of hair loss, nausea, neuropathy and weight loss.

The committee could recommend approval of the drug as a primarytherapy for KS, recommend approval as a second-line therapy, orreject the data. Earlier this year ODAC recommended acceleratedapproval for Menlo Park, Calif.-based Liposome Technology Inc.'sliposomal formulation of doxorubicin, but that was based on Phase IIstudies, which led some committee members to question whether thedata were adequate and well-controlled.

"We're proud of this study because it's the first Phase III trial evercompleted for a Kaposi's sarcoma treatment," Alper said. The trialinvolved 227 HIV-positive patients who had advanced-stage KS. Thepatients got either DaunoXome or the standard three-drug therapy.

Patients were injected with the liposomal drug once every two weeksfor 12 weeks. Survival data up to 24 months is available, Alper said.

Sales of NeXstar's Ambisome, which is approved in 18 countries,were $43 million. NeXstar sells the product itself outside ofScandinavia, and has the same sales strategy for DaunoXome. Alpersaid the company has no marketing partner in the U.S and nointention of getting one at this point.

Phase II trials of DaunoXome are ongoing in breast cancer, leukemia,lymphoma and small-cell lung cancer.

NeXstar's stock (NASDAQ:NXTR) was up 13 cents Monday, anddown 50 cents Tuesday to close at $7.50 per share. n

-- Jim Shrine

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