WASHINGTON (AP) — U.S. financial regulators are demanding drugmaker Elan Corp. turn over records about a potentially lethal brain disease linked to its drug Tysabri, according to a government filing form. The Irish company said it received a subpoena from the Securities and Exchange Commission for documents connected with its announcement last July of two cases of progressive multifocal leukoencephalopathy, or PML. The company disclosed the subpoena in a regulatory filing Tuesday. The SEC is also seeking information on trial results for the company’s experimental Alzheimer’s drug bapineuzumab, which were released last July. PML is a rare but can cause deadly inflammation in the brain. There have been 13 reported cases of PML since mid-2006. Last week the Food and Drug Administration said the risk of the inflammation appears to increase as patients remain on Tysabri. Tysabri is co-marketed with Cambridge, Mass.-based Biogen Idec Inc. for multiple sclerosis and Crohn’s disease. All the PML cases are linked to its use in multiple sclerosis. The drug was approved in November 2004 and pulled from the market the next year due to PML reports. It was reintroduced in July 2006, and Biogen said it is used by 43,000 patients.