Marvel Biosciences Reports MB-204 as Highly Effective at Treating Autism Behaviours in Shank3 Mouse Model

CALGARY, Alberta, Oct. 08, 2026 (GLOBE NEWSWIRE) -- Marvel Biosciences Corp. (TSXV: MRVL | OTCQB: MBCOF), and its wholly-owned subsidiary, Marvel Biotechnology Inc. (collectively the “Company” or “Marvel”), a drug discovery company developing novel therapeutics for autism spectrum disorder (“ASD”) and related neurodevelopmental disorders, is pleased to announce preliminary results from its preclinical study of MB-204 in the Shank3Δex13-16 mouse model, a model associated with Phelan-McDermid syndrome. The study was conducted in collaboration with Dr. Julie Le Merrer and Dr. Jérôme Becker at the iBraiN Institute in Tours, France, and evaluated MB-204 at oral doses of 1 mg/kg and 2.5 mg/kg compared with Istradefylline at 1 mg/kg, the highest dose tested that did not affect locomotion.   Animals were studied for one to three hours post dosing. Istradefylline is a clinically approved drug for the treatment of Parkinson’s Disease.

Preliminary Results Demonstrate Broad Activity of MB-204

The preliminary results indicate that MB-204 produced improvements across multiple behavioural endpoints associated with repetitive and abnormal behaviours in the Shank3 model. MB-204 continues to demonstrate activity across increasingly diverse genetic models, supported by the emerging Shank3 data, potentially advancing a broader therapeutic opportunity as the company approaches human clinical development.

Key Data Highlights

• Low-dose MB-204 (1 mg/kg) matched or exceeded Istradefylline across the majority of measured endpoints: performance was matched on the number and time of nose contacts, number and time of paw contacts, the number of grooming episodes and number of same arm returns (SARs) in the Y-maze test of repetitive behaviour.
• Low dose of MB-204 demonstrated superior performance to Istradefylline on the mean duration of paw contacts, number of following episodes and the number of spontaneous and alternate arm returns (AARs) in the Y-maze. Only the number of rearing episodes was Istradefylline more effective than low dose MB-204.
• High-dose MB-204 (2.5 mg/kg) was superior to Istradefylline across the majority of measured endpoints: performance was matched only in the number of grooming episodes, rearing episodes and SARs. On all other endpoints as per above, MB-204 was superior to Istradefylline.
• All treatments showed demonstrable improvement in multiple behavioural endpoints over untreated Shank3 animals except for the number of following episodes and AARs in the Istradefylline treated animals.
• The study also provides a direct head-to-head comparison between MB-204 and its parent compound, Istradefylline, supporting the Company's objective of demonstrating differentiated activity for its proprietary fluorinated derivative.
• Final statistical analyses and additional endpoints remain pending.
  

* The Company cautions that these are preliminary preclinical findings and that additional analyses may modify the interpretation of individual endpoints.

“This is the third model where MB-204 has had a profound effect on socialization and repetitive behaviours,” said Drs. Le Merrer and Becker, “which are the key hallmarks of autism. MB-204 nearly reversed all the social deficits and repetitive behaviours in the Shank3 model as we previously saw in the Oprm1 mouse model and Rett syndrome models. This study also confirms the superiority of MB-204 over the parental drug Istradefylline in a head-to-head study. Together with the recent Fragile X results, the data suggests MB-204 may be a pan-spectrum treatment for autism. We look forward to presenting the data in upcoming conferences and publishing the data on MB-204 for the wider scientific community to review.”

Expanding Evidence Across Genetically Distinct Neurodevelopmental Models

The Shank3 findings add to a growing body of preclinical evidence generated for MB-204 across genetically distinct models of neurodevelopmental disorders.

Marvel has previously reported positive preclinical results in:

• Oprm1: an autism model in which MB-204 demonstrated restoration of social interaction and improvements in repetitive behaviours following oral administration. 
• Mecp2/Rett syndrome: MB-204 demonstrated near-reversal of social and behavioural deficits and outperformed Trofinetide across multiple endpoints in the Company's disclosed preclinical study. 
• Fragile X (Fmr1): MB-204 produced statistically significant improvements in behavioural and cognitive function, including a carry-over effect after treatment cessation. 
• Shank3: representing another genetically distinct model associated with autism and Phelan-McDermid syndrome.
  

The Company believes that the emergence of consistent behavioural activity across models associated with different underlying genetic causes may be important in evaluating the potential breadth of MB-204's mechanism and therapeutic application.

“The Shank3 results are particularly encouraging because they add another genetically distinct model to the growing body of evidence supporting MB-204,” said Dr. Mark Williams, President and Chief Science Officer of Marvel Biosciences. “Together with our previously reported Oprm1, Mecp2 and Fragile X results, these findings continue to support our hypothesis that targeting the adenosine A2A receptor may address behavioural and social deficits across multiple neurodevelopmental disorders. We look forward to completing the statistical analysis and presenting the full dataset to the scientific community.”

About Marvel Biosciences Corp.

Marvel Biosciences Corp. (TSXV:MRVL | OTCQB:MBCOF), and its wholly-owned subsidiary, Marvel Biotechnology Inc., is a Calgary-based pre-clinical stage pharmaceutical development biotechnology company. The Company is developing MB-204, a novel fluorinated derivative of the approved anti-Parkinson’s drug Istradefylline, the only clinically approved adenosine A2a antagonist. A significant and growing body of scientific evidence suggests drugs that block the adenosine A2a receptor, such as MB-204, could be useful in treating other neurological diseases such as autism, depression and Alzheimer’s Disease. The Company is actively investigating its potential in addressing other neurodevelopmental disorders, such as Rett Syndrome and Fragile X Syndrome, to expand its therapeutic reach.

Contact Information: Marvel Biosciences Corp.

J. Roderick (Rod) Matheson, Chief Executive Officer
Email: rod@marvelbiosciences.com
Dr. Mark Williams, President and Chief Science Officer
Email: mark@marvelbiosciences.com
Tel: 403 770 2469

Website: www.marvelbiotechnology.com    |   Twitter/X   |   LinkedIn

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