Does Kevetrin stop working after a period of time?

Does Kevetrin stop working after a period of time?  Do those patients in the first Cohort build up a large amount of Kevetrin over the life of the trials due  to a cumulative effect from all the prior cohort doses?  Would this cause them to reach MTD long before those in later cohorts reach it?

Would you expect that the MTD would be administered to patients like the trials where they would get an MTD each week for a number of weeks to be effective?  After that and the p53 gene starts working again, does it keep working for the life of the patient or might they need treatment again should cancer return of another type later in the patient's life by again shutting down the p53 gene?

I know many of these questions will be answered during the 3 phases of the trials but would appreciate best guess from the scientific team.