Cher has filed a lawsuit against pharmaceutical company executives alleging she was duped into selling shares.

Legal advisors for the 71-year-old entertainer filed documents at the Los Angeles Superior Court on Friday (29Sep17), accusing bosses at Florida-based Altor BioScience of advising her to sell back stock in the company, without disclosing that they had made a major breakthrough regarding HIV and cancer treatments.

According to editors at The Los Angeles Times, the documents state that Cher purchased a minority stake in the company for an undisclosed amount via the Inshallah Trust, of which she acts as a trustee.

In January 2016, Cher sold the shares for a total of $450,000 (£335,000) after allegedly being contacted by a senior Altor executive. However, Cher's suit claims that when she was asked to sell her stake, she wasn't informed that a specific Altor drug was showing promise.

The lawsuit alleges fraudulent concealment and breach of fiduciary duty, with Cher's lawyers seeking damages as well as reimbursement of legal fees.

Defendants include billionaire surgeon and businessman Dr. Patrick Soon-Shiong, as well as Altor Acquisition LLC, and company founder and chief executive officer Dr. Hing C. Wong. Other shareholders who own a minority stake have filed a separate lawsuit.

Through his company NantCell, Dr. Soon-Shiong acquired the shares of Altor, clinical-stage biopharmaceutical company developing novel immunotherapies, in 2016.

A spokesperson for the medical entrepreneur has rejected claims within Cher's lawsuit, and told The Los Angeles Times, "The lawsuit has no merit. We intend to vigorously defend against it."