Despite slow action on Capitol Hill, the Bush administration is moving forward to create defenses against biological terrorism and expects to place a big new order for anthrax vaccine by late this summer, one of the government's top health experts said Monday.

Philip K. Russell, a top bioterrorism adviser in the Department of Health and Human Services, also revealed that the government plans to buy a new type of treatment for people infected with anthrax, in addition to vaccines that could be used to prevent infection. The proposed purchase suggests one or more companies in the Washington region could be in line for lucrative government contracts to produce an anthrax drug.

Among the top contenders is Human Genome Sciences Inc. of Rockville. The company has reported considerable success in laboratory tests of such a product, but until now it had been unclear whether the government would commit to buying a drug of this type. Even with Russell's pledge, it is far from certain Human Genome Sciences will land the contract, since the government is still trying to figure out which company's drug might offer the best treatment.

Congress has yet to pass Project Bioshield, a broad package of legal changes that President Bush requested in early 2003 to give the government more authority to create and stockpile drugs to combat biological terrorism. A logjam in the Senate was broken only recently, and now the House and Senate must pass identical versions of the legislation before President Bush can sign it.

Even without Project Bioshield on the books, though, Congress has been appropriating large sums for biodefense projects. The government is moving forward on multiple fronts to develop new measures to defend the nation, Russell and other administration officials said here at the annual convention of the Biotechnology Industry Organization.

Russell's remarks came as he and other officials in the Bush administration, including experts from the Pentagon, sought to enlist biotechnology companies in building a broad national defense against biological weapons.

He said the government hoped by late summer to place an order for a new type of vaccine against anthrax sufficient to inoculate 25 million people. That would be enough to mount a defense in a large-scale attack, such as terrorists spreading anthrax over a city by plane. The scale of the plan had been disclosed previously, but it wasn't clear until now how fast the government would move. If an order is placed this summer, companies have said, a large stockpile of anthrax vaccine could be in the government's storerooms by next year.

Russell said the new vaccine, designed to replace an old, primitive type of anthrax shot, won't be perfect. It will have a relatively short shelf life, for instance. "I hope we get up to six years out of this product, but I can't be sure of that," Russell said.

Research will continue to develop another vaccine that might last longer, Russell said.

Russell added that plans are also moving forward to acquire a type of drug that might be used to treat victims of anthrax exposure, with bid specifications to be disclosed "in the very near future." People exposed to anthrax can be treated now with long courses of antibiotics, but some victims who are already sick from the infection can't be saved that way. Scientists have said a new drug using antibodies, a type of protein produced by the immune system, might offer better treatment.