WASHINGTON -- At a time when the Clinton administration is trying to send more U.S. medicines to Cuba, a multinational drug firm is hoping to turn the tables and bring a Cuban vaccine to the United States.

SmithKline Beecham Pharmaceuticals has quietly asked the administration for permission to test a vaccine developed in Cuba to fight meningitis B, a sometimes fatal disease that particularly affects young children.

Although SmithKline is a British company, the laboratories it wants to use to test the vaccine are owned by its U.S. subsidiary, raising the need for U.S. approval of a license to work with and, potentially, to pay millions of dollars to the government of Cuban President Fidel Castro.

The firm's request is likely to stir a hornet's nest of competing interests, pitting political supporters of the 36-year economic embargo of Cuba against medical and business leaders who see the potential for earning huge profits and helping thousands of victims worldwide.

At stake, too, is the image of Cuba's biotech industry, which has so far failed to become the cash cow the Castro government hoped despite vast infusions of state funds into the quest for cures to everything from AIDS to impotence. Cuba claims to have wiped out meningitis B on the island and has marketed its vaccine in Brazil and Argentina for tens of millions of dollars, though its efficacy has not been rigorously demonstrated.

Meningitis B is one of several strains of infection of the fluid that surrounds the brain and is in the spinal cord. Bacterial in nature, it is more severe than viral meningitis, and is characterized by high fever, headache and stiff neck. It can be spread by coughing or kissing and has about a 12 percent mortality rate.

The administration is currently considering SmithKline's request, said James Dobbins, President Clinton's national security aide for Latin America. ``They obviously are sufficiently intrigued with it to think it's worth doing,'' he said.

The administration's dilemma comes as U.S. officials are scrambling to ease restrictions on the sale of U.S. medicines in Cuba. Prodded by Pope John Paul II and other humanitarian advocates, Clinton in March ordered procedures simplified for U.S. firms to sell medicines and medical equipment on the island.

Rep. Bob Menendez, a New Jersey Democrat who strongly supports the U.S. embargo, voiced discomfort at allowing Havana to market a vaccine abroad, saying it would deprive average Cubans of basic medicines.

``It's ironic that, at a time when Cuba is claiming it has a dire need for medicine, they're going to sell a vaccine to a U.S. subsidiary for millions of dollars,'' Menendez said. ``It's a huge contradiction.''

Menendez, who plans to meet with SmithKline representatives today, said he will recommend that the firm compensate Cuba in kind, that is, with U.S. medicines Cuba says it needs.

Dr. Nancy Rosenstein, a meningitis expert at the Centers for Disease Control in Atlanta, said that each year about 1,000 people in the United States contract meningitis B, and roughly 120 people die.

``We think it's a high priority to get an effective serogroup B vaccine to address this problem in the Americas,'' Rosenstein said.

While there are vaccines available for three other types of bacterial meningitis, serogroup B has foiled traditional approaches, and the United States has no vaccine for it, she said. Vaccines being developed in Cuba and elsewhere ``deserve further study,'' she said.

In 1987, 100,000 Cuban schoolchildren were inoculated with the vaccine developed by the Instituto Carlos Finlay in Cuba. It was reported to be 83 percent effective, according to the Pan American Health Organization.

Brazil paid between $80 million and $100 million for a mass immunization during an outbreak beginning in 1990. In Sao Paulo, 2.4 million children were vaccinated. In children over 4 years old, the vaccine was 74 percent effective, PAHO said. Officials stressed that the data were not conclusive.

SmithKline, which has developed vaccines for everything from hepatitis A and B to polio to tetanus, wants to test the efficacy and safety of the Cuban vaccine in its laboratories in Belgium. But those labs are owned by a U.S. subsidiary of the firm, making them subject to U.S. laws restricting commerce with Cuba.

``In the vision of our scientists, it needs additional work and development,'' said Richard Koenig, a spokesman for SmithKline based in Philadelphia. ``But it is the vaccine that is furthest along and, in our view, offers the best chance over the intermediate term against this serious disease.''

The scientific challenge, he said, is to make the vaccine more effective for the most vulnerable victims: children younger than age 5. The political challenge, however, will be to find a way to collaborate with the Cuban government in the face of perhaps the most stringent U.S. economic sanctions anywhere.

``Ultimately, if some years from now, an effective vaccine comes out of this, one would hope its protection would be afforded U.S. citizens,'' Koenig said. ``We're seeking guidance here to see what we need to do.''