One 131I-omburtamab treatment cycle takes 4 weeks and includes a treatment dose, and an
observation period and post-treatment evaluations.
One 131I-omburtamab treatment cycle for Japan only takes 5 weeks and includes a dosimetry
dose (2mCi) of 131I-omburtamab is administered during week 1 followed by blood/cerebral
spinal fluid (CSF) samples and whole-body scintigraphy at predefined intervals during the
following 48 hours after treatment.
- - A therapeutic dose (50mCi) of 131I-omburtamab is administered during week 1 (week 2 for
Japan) followed by a 3-week observation period that includes a repeated MRI, CSF
cytology, and safety monitoring.
- - A second treatment cycle of 131I-omburtamab is administered during week 5 (week 6 for
Japan) if there is no objective disease progression week 5 after the first injection,
and the participant is presenting without unexpected and clinical significant Grade 4
For participants with ongoing Grade 3 toxicity a second doing cycle will take
place according to the discretion of the investigator.
Participants can be treated in an outpatient setting or may be admitted as inpatients for
both the dosimetry and the therapeutic injections.
Participants completing at least one treatment period will first enter a follow-up period
through week 26 and thereafter the long-term follow-up where patients will be evaluated for
up to 3 years post-131I-omburtamab treatment where after the trial is ended. Participants will be monitored for adverse events during and after 131I-omburtamab injection
and will have pre- and post-treatment clinical assessments including neurologic examination,
hematology and serum chemistry, blood and CSF cultures, endocrinology assessments, CSF
analysis, and, pre- and post 131I-omburtamab performance testing. Performance testing will be
performed at trial baseline, at week 26 and every 6 months during trial period.
In case the patient has a subsequent relapse in the CNS/LM after 131I-omburtamab therapy
during the follow-up period, re-treatment to target minimal residual disease can be
considered and allowed.