Rocket’s Danon update raises specter of worst-case scenario, Leerink says

Leerink notes that Rocket Pharmaceutics announced an unexpected serious adverse event in its Phase 2 trial of RP-A501 for Danon disease, which led to a voluntarily pause of further dosing and FDA clinical hold. The SAE involved complications related to a capillary leak syndrome and the patient has since passed away after an acute systemic infection. This news is foremost a tragedy for the patient and family, and the implications for the Danon program are potentially disastrous, the firm says. Given already poor market sentiment on gene therapy, Leerink believes that reassuring investors on a path off clinical hold and to approvability will be a tremendous challenge. The firm has an Outperform rating on the shares.