you attend the first study visit after joining the trial. you sign the consent form and a study nurse records your medical history, current symptoms of relapsing‑remitting multiple sclerosis, vital signs, and performs an electrocardiogram (ecg).

baseline laboratory tests are taken, including blood work to measure cd19+ b cells and any existing anti‑drug antibodies.

a blood sample is drawn to establish the initial level of ocrelizumab in your circulation and to assess baseline immune markers.

the sample is also used to evaluate the presence of anti‑drug antibodies before any medication is given.

you receive a single dose of 920 mg of ocrelizumab as a subcutaneous injection (injection under the skin). the injection is administered by trained study staff according to the study protocol.

after the injection you are observed for a short period for any immediate reactions. vital signs such as blood pressure and heart rate are checked.

you attend scheduled follow‑up visits throughout the study period. at each visit blood samples are taken to measure pharmacokinetics (how the drug moves in your body), cd19+ b cell counts, and anti‑drug antibodies.

vital signs, ecg, and selected laboratory tests are repeated to monitor safety.

any symptoms you experience are recorded as potential adverse events.

throughout the trial you are asked to report any new or worsening symptoms. the study team grades each event using a standard severity scale.

if an adverse event is severe, the study medication may be discontinued according to the protocol.

at the end of the study you undergo a final set of evaluations similar to the baseline visit, including a blood draw, vital signs, ecg, and laboratory tests.

the collected data are used to evaluate the overall safety, tolerability, and pharmacokinetic profile of the subcutaneous ocrelizumab dose in children and adolescents with relapsing‑remitting multiple sclerosis.