LEXINGTON, Mass. (AP) — Epix Pharmaceuticals Inc. has disclosed that its independent auditor expressed concern about the Lexington-based company's ability to remain in business. In a March 13 filing with the Securities and Exchange Commission, Epix said the accounting firm Ernst & Young LLP "expressed substantial doubt about our ability to continue as a going concern." The auditors said that in the future the firm may not be able to raise additional capital on acceptable terms. The company made a public announcement about the filing on Wednesday to comply with Nasdaq rules. Epix, which is conducting clinical trials on an Alzheimer's drug, announced earlier this month that it was slashing its workforce in half.