FDA puts Rocket Danon disease trial on hold following patient death

The U.S. FDA placed a clinical hold on Rocket Pharmaceuticals’ phase 2 pivotal trial of its experimental gene therapy, RP-A501, after a patient experienced a serious adverse event.

Rocket had paused dosing the trial after a patient experienced clinical complications related to a capillary leak syndrome. The FDA hold was placed on the trial on Friday May 23, and unfortunately the patient has since passed away after an acute systemic infection.

Rocket is conducting a comprehensive root cause analysis and remains in active dialogue with the FDA and other key stakeholders, with the current focus being on the recent introduction of a novel immune suppression agent to the pre-treatment regimen that had been implemented to mitigate complement activation observed in some patients.

Rocket says it is committed to ensuring the safety of all study patients while resuming the trial as expeditiously as possible. With the hold in place, the company is unable to provide guidance on the anticipated timing for completion of the phase 2 trial.

RP-A501 is a single dose treatment administered as an intravenous infusion for the treatment of Danon disease, a rare, serious cardiac and skeletal myopathy caused by mutations in the LAMP2 gene. RP-A501 consists of a recombinant adeno-associated serotype 9 (AAV9) capsid containing a full-length, wild-type version of the human LAMP2B transgene (AAV9.LAMP2B) which, when inserted into heart cells harboring mutations in the endogenous LAMP2 gene, has the potential to fully restore cardiac function at its root.