Shares of Capricor Therapeutics plummeted to a new 52-week low on Thursday after another regulatory setback in the biotechnology company's quest for approval of its proposed deramiocel cell therapy for Duchenne muscular dystrophy, or DMD.

Capricor shares, which fell 64% on Monday after briefing materials released ahead of a Food and Drug Administration advisory committee meeting to discuss deramiocel, were recently down 53% to $3.11 after the panel voted to recommend against approval of the drug.

The stock touched a 52-week low of $3.07 early in the session.

The FDA, which rejected Capricor's initial application for deramiocel last July, held the advisory committee meeting on Wednesday as it reviews the company's resubmitted application, which is seeking approval of deramiocel for the treatment of cardiomyopathy associated with DMD.

The briefing documents released Monday indicated that the agency believes the company's data doesn't provide substantial evidence of deramiocel's effectiveness, and the advisory committee voted 9-3 against the drug.

Capricor on Monday said the post-hoc analyses in the FDA's briefing materials relied on an incomplete internal draft of a statistical analysis plan that became obsolete with the addition of another cohort to the company's Phase 3 study of deramiocel and didn't include content specifically requested by the agency.

The San Diego company on Thursday said it remains committed to deramiocel and to the patients who could benefit from it, and that it is focused on working with the FDA toward potential approval ahead of the agency's Aug. 22 target action date.

The FDA often turns to advisory committees to obtain advice from experts who work outside of the government when a scientific, technical or policy question arises, such as whether an unapproved product is safe and effective. The agency usually follows the advice of its advisory committees but it isn't bound by the recommendations.