The top leaders of the State Senate have filed a last-minute bill to plug the gap in the new federal prescription drug prgoram. The new federal law cuts off coverage at the $2,500 dollar level and does not resume it until a person has spent $5,000 on drugs. Senate Leader Peter Kinder of Cape Girardau says the program will replace the present SeniorRX program. The program will pick up 75 percent of the costs of prescriptions for senior citizens not covered by the federal plan. Senate Minority Leader Ken Jacob of Columbia is co-sponsoring the bill with Kinder.