after you join the study, you will undergo a series of baseline assessments that include a physical examination, collection of medical history, and laboratory tests such as blood work and bone‑marrow analysis to confirm eligibility and document the status of your disease.

the results of these assessments establish a reference point for later comparison while you receive study medication.

you will begin taking s241656 as a single oral tablet. the study provides tablets that contain either 25 mg or 50 mg of the active substance; the exact dose and any future adjustments are defined by the study protocol.

the tablet is taken by mouth once daily, preferably at the same time each day, and you will continue this dosing throughout each treatment cycle.

the first treatment cycle is typically 28 days long; during this period the study team closely monitors safety and tolerability.

throughout the 28‑day cycle you will attend scheduled clinic visits where vital signs, physical condition, and any symptoms are recorded.

regular laboratory tests, including blood counts and chemistry panels, are performed to detect any changes that might indicate a dose limiting toxicity or other adverse event.

if a serious side effect occurs, the study medication may be reduced, temporarily stopped, or discontinued according to the protocol.

after the initial safety evaluation, you may be offered the optional part 1b, in which you will take the antifungal drug posaconazole together with s241656.

posaconazole is taken orally, usually once daily, at a dose specified in the study protocol; its purpose is to assess how a strong CYP3A4 inhibitor affects the levels of s241656 in the bloodstream.

you will continue to take both medications for several days until steady‑state concentrations are reached, after which additional blood samples are collected to measure drug levels.

if you remain eligible and no unacceptable toxicity occurs, you will start additional 28‑day cycles of s241656 (and posaconazole if you are in part 1b).

each new cycle repeats the same pattern of daily dosing, periodic clinic visits, and laboratory monitoring.

the study protocol may allow dose adjustments, temporary interruptions, or permanent discontinuation based on safety findings.

at predefined times, usually after several cycles, disease‑specific evaluations are performed to determine whether the leukemia or myelodysplastic syndrome has responded to treatment.

responses may include complete remission, partial remission, or other measures of disease control; these assessments are made by the study physicians using standard criteria.

treatment may be stopped after a set number of cycles, if disease progression is observed, or if side effects become severe enough to outweigh potential benefit.

the decision to discontinue is based on the safety and efficacy data collected during the trial.

after the last dose of study medication, you will continue to attend follow‑up visits for a period defined by the protocol.

these visits include physical examinations, laboratory tests, and disease assessments to monitor long‑term safety and any lasting effects of the treatment.