The US Food and Drug Administration (FDA) has granted approval for Zydus Lifesciences to proceed with a randomised Phase IIb trial of its oral NLRP3 inflammasome inhibitor, Usnoflast, for amyotrophic lateral sclerosis (ALS) treatment.

The multi-centre, placebo-controlled, double-blind trial will assess the therapy’s safety, pharmacodynamics, efficacy, and pharmacokinetics in adult ALS patients.

Sean M Healey & AMG Centre for ALS director professor Merit Cudkowicz will lead the study as principal investigator. The trial aims to enrol 210 subjects and will test two different therapy doses of 50mg and 75mg against a placebo.

The trial will last 36 weeks, followed by an open-label extension for an additional 16 weeks.

The trial's primary endpoint is the change in the ALS Functional Rating Scale-Revised (ALSFRS-R) total score from baseline to week 36. Secondary endpoints include changes in slow vital capacity (SVC) and neurofilament levels in the cerebrospinal fluid (CSF).

In addition, the study will analyse biomarkers such as high-sensitivity C-reactive protein (hs-CRP), interleukin (IL)-18, IL-6, IL-1β, NLRP3, and serum amyloid A (SAA).

Zydus Lifesciences chairman Pankaj Patel said: “We are excited to report the approval from the USFDA to initiate this randomised, double-blind, placebo-controlled Phase IIb clinical trial in ALS patients. Zydus is committed to unlocking new frontiers in neuroscience and developing transformative breakthrough medicines.”

Also known as ZYIL1, Usnoflast has been explored in various pre-clinical studies for neuroinflammation and other conditions. The company has also secured orphan drug status for the therapy from the FDA for treating Cryopyrin Associated Periodic Syndrome (CAPS).

ALS is characterised by rapid neurodegeneration, it leads to severe physical disabilities and death, primarily due to respiratory failure.

Last May, Zydus Lifesciences completed enrolment in a Phase II trial for the therapy in India, involving 24 ALS subjects across seven trial sites.