Update on Food and Drug Administration (FDA) Type C meeting regardingromaciclib (RVU120)

The Management Board of Ryvu Therapeutics S.A., with its registeredoffice in Kraków (the "Company", "Ryvu") announces that on January 16,2026, the Company received the minutes of the Type C meeting with theU.S. Food and Drug Administration, which was held on January 13, 2026,regarding the component of the romaciclib (RVU120) development programrelated to its combination with venetoclax for the treatment of patientswith relapsed or refractory acute myeloid leukemia (R/R AML) followingfailure of venetoclax in combination with a hypomethylating agent. Thisindication is currently being tested in the RIVER-81 study. The otherindications in which romaciclib is being developed by Ryvu were notdiscussed at this meeting.

The purpose of the meeting, which was held at Ryvu's request, was toobtain FDA's feedback on the further clinical development of romaciclibin patients with R/R AML in the United States, in particular withrespect to the observed benefit-risk profile. Ryvu also asked forguidance on dose optimization and design assumptions for futureregistrational clinical studies.

The FDA raised no objections to opening the expansion cohort in theUnited States with romaciclib at a dose of 150 mg once daily (QD- once aday) in combination with venetoclax, which was assessed in Cohort 4 ofthe RIVER-81 study.

At the same time, the FDA provided the Company with general guidanceregarding:

- expectations related to dose optimization based on an integratedanalysis of safety, pharmacokinetic, and pharmacodynamic data;

- clinical trial design for combination therapies, including thestandard approach involving randomization in studies with registrationalintent;

- the need for further clinical data generation prior to defining aregistration pathway.

Next Steps

Following the FDA meeting, the Management Board of the Company plans toundertake the steps required to initiate the dose expansion ofromaciclib at 150 mg QD in the United States, including, in particular:

- updating the RIVER-81 study protocol, including clarification ofsafety criteria and the rationale for dose and regimen selection;

- submission of updated documentation to the FDA under the existingInvestigational New Drug (IND) application, in line with the feedbackreceived;

- initiation of patient enrollment in the U.S. expansion cohortfollowing completion of the above regulatory steps.

After obtaining more mature clinical data from the expansion stage, theCompany plans to hold a subsequent regulatory meeting with the FDA todiscuss the further clinical development strategy for the romaciclibprogram in the aforementioned regulatory pathway.

Disclaimer: This English language translation has been prepared solelyfor the convenience of English-speaking readers. Despite all the effortsdevoted to this translation, certain discrepancies, omissions orapproximations may exist. In case of any differences between the Polishand the English versions, the Polish version shall prevail. RyvuTherapeutics S.A., its representatives and employees decline allresponsibility in this regard.