FDA clinical hold on REGENXBIO's RGX-121 for MPS II; BLA resubmission not expected near term

REGENXBIO Inc.

• FDA clinical hold on RGX-121 after asymptomatic spine MRI findings in 5 CAMPSIITE study participants.
• REGENXBIO does not expect to resubmit RGX-121 BLA in near term; longer follow-up and data analysis needed.
• All five participants clinically stable/improving; findings deemed nonserious, likely benign by investigators.
• Company reaffirms Duchenne BLA submission this quarter and wet AMD pivotal data in Q4.
• Hold follows earlier RGX-111 clinical hold; expanded MRI monitoring to include brain and spine.