Calgary, Alberta--(Newsfile Corp. - April 30, 2025) - Marvel Biosciences Corp. (TSXV: MRVL) (OTCQB: MBCOF), and its wholly owned subsidiary, Marvel Biotechnology Inc. (collectively the "Company" or "Marvel"), is pleased to share part of the second final data set from its preclinical Rett syndrome study conducted in collaboration with Dr. Julie Le Merrer and Dr. Jerome Becker at the iBraiN Institute.

The study evaluated MB-204, Marvel's lead compound (10 mg/kg oral once daily), in comparison to Trofinetide (100 mg/kg injected i.p. once daily), the only FDA and Health Canada approved treatment for Rett syndrome. Mecp2 mice were treated for approximately two weeks with either compound and then treatment ceased. Animals were monitored for up to three weeks post-treatment to study the carry-over effect of the drug.

Key Data Highlights:

• Week 1: MB-204 continued to reverse social behavioural deficiencies as measured by the number and duration of nose contacts, the number and duration of paw contacts, the number of following episodes and in the 3 Chamber Test (p<0.0001 vs control). Trofinetide only showed an improvement on following episode (p<0.05 vs control). MB-204 was significantly better than Trofinetide on the same endpoints (p<0.0001 except following episodes p<0.01). The 3 Chamber Test was conducted on day 10 post treatment.
• Week 2: MB-204 continued to maintain its positive effect on the number and duration of nose contacts, in addition to a continued effect on following episodes (p<0.0001 vs control), and outperformed Trofinetide (p<0.0001 and p<0.05 on the same respective endpoints). Trofinetide showed no discernible carry-over effect.
• Week 3: MB-204 continued to maintain its positive effect on nose contacts and following episodes (p<0.0001 vs control). The Trofinetide was not studied owing to the lack of any discernible carry-over effect in the previous week.

"These results are very encouraging," said Drs. Le Merrer and Becker. "MB-204 nearly reversed all the social deficits in the Mecp2 model while under treatment as we previously saw after a single dose in the Oprm1 mouse model of autism. This study suggests the drug does not reduce its effectiveness after chronic dosing, and we were pleasantly surprised by the continued carry-over effect seen at week 3 which suggests a profound sustained effect of MB-204. We look forward to seeing MB-204 advance as a novel treatment for Rett syndrome and autism in general".

The Company and its collaborators intend to present the data as an oral presentation at the International Rett Syndrome Foundation (IRSF) Scientific Meeting, taking place in Boston, June 9-11th, 2025.

About Marvel Biosciences Corp.

Marvel Biosciences Corp., 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:

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