RVU305 (PRMT5i) and ONCO Prime Platform data to be presented at the 2025AACR-NCI-EORTC International Conference on Molecular Targets and CancerTherapeutics

The Management Board of Ryvu Therapeutics S.A., headquartered in Kraków(the "Company," "Ryvu"), informs that the Company is presentingpreclinical data on RVU305 (PRMT5i) and the ONCO Prime Platform at the2025 AACR-NCI-EORTC International Conference on Molecular Targets andCancer Therapeutics, October 22-26, 2025, in Boston, MA.

Details on the poster presentations are as follows:

Poster Title:"RVU305, a brain-penetrant MTA-cooperative PRMT5inhibitor, shows efficacy in GBM preclinical models"

Poster Number: B037

Session date and time:Friday, October 24, 12:30 PM - 4:00 PM EST

RVU305, a potentially best-in-class, brain-permeable MTA-cooperativePRMT5 inhibitor, demonstrates significant promise in the treatment ofMTAP-deleted cancers. Preclinical studies show that RVU305 selectivelyinhibits PRMT5 activity in MTAP-deleted cells, inducing a strongsynthetic lethal effect while sparing regular counterparts.Mechanistically, RVU305 causes a dose-dependent reduction inSDMA-modified proteins, validating PRMT5 inhibition at the molecularlevel. Moreover, RVU305 delivers selective inhibition of PRMT5 inMTAP-deleted tumor cells. Its BID oral dosing and MTA-cooperativemechanism enable potent, on-target tumor inhibition while sparinghealthy tissue. This translates into >100% tumor growth inhibition andmultiple complete responses in MTAP-deleted models.

RVU305 demonstrates potent antiproliferative activity across multipleMTAP-deleted glioblastoma (GBM) cell lines with minimal effects on MTAPwild-type lines. In vivo, RVU305 showed significant tumor growthinhibition (TGI) and good tolerability in an orthotopic U87-LUCglioblastoma mouse model. RVU305 demonstrated CNS penetration withpredicted efficacious exposure in the brain of cynomolgus monkeys. Kp,uumodeling indicates brain target coverage significantly superior toclinical stage comparator.

Together, these findings position RVU305 as a promising therapeuticcandidate capable of delivering targeted, brain-penetrant efficacy forMTAP-deleted gliomas, addressing a critical unmet medical need in GBMtreatment. GLP toxicology studies for RVU305 have been completed with nomajor toxicology findings and favorable safety profile which supportsplanned completion of IND/CTA-enabling studies in Q4 2025.

Poster Title:"Identification of novel molecular vulnerabilities incolorectal cancer through integrated transcriptomic profiling andfunctional genomics"

Poster Number: B050

Session date and time: Friday, October 24, 12:30 PM - 4:00 PM EST

This study describes the development of a comprehensive discoveryplatform designed to identify synthetic lethal (SL) interactions linkedto major oncogenic drivers in colorectal cancer (CRC), including APC,KRAS, and SMAD4. By combining CRISPR-based functional screening withgenomic and transcriptomic analyses across human intestinal stem cell(hISC)-derived isogenic models, patient-derived cells (PDCs), andclinical tumor specimens, the team uncovered novel molecularvulnerabilities specific to genetically defined CRC subtypes. Machinelearning applied to RNA sequencing data enabled precise molecularsubtyping and validation of model fidelity, while candidate targets wereselected based on therapeutic relevance and selectivity for cancercells. Through this integrated approach, three categories of actionabletargets were identified:

- first-in-class synthetic lethal targets currently under active drugdiscovery and optimization,

- next-wave novel dependencies representing promising directions forfuture oncology programs,

- novel indications for FDA-approved drugs supporting opportunities fordrug repurposing.

Together, these findings establish a robust framework for precisiononcology, supporting the discovery of new targeted therapies for CRC andoffering broad applicability to other cancer types. .

All posters are now available online and can be obtained from theconference site:

https://www.aacr.org/ and https://ryvu.com/

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