Neurizon Therapeutics' (ASX:NUZ) investigational new drug application for NUZ-001 was placed under clinical hold by the US Food and Drug Administration amid concerns about the sufficiency of information to assess the application, potential risks to human subjects, and the proposed dosing regime, according to a Friday filing with the Australian bourse.

The company is developing NUZ-001 as a potential treatment for amyotrophic lateral sclerosis, a motor neuron disease.

The US FDA is expected to provide detailed feedback within 30 days, providing necessary clarifications to progress the application, the filing said.

Shares fell past 26% in midday trade Friday and earlier hit a new 52-week low.