Sites & Operations
First Patient In (FPI)
First Patient In (FPI) is the milestone marking the date the first participant in a clinical trial is randomized or enrolled at any activated site, formally ending the startup phase and beginning the enrollment phase.
FPI is the most-watched startup KPI by sponsors and investors. It is preceded by First Site Activated (FSA) and followed by Last Patient In (LPI) and Last Patient Last Visit (LPLV).
Time to FPI from protocol finalization typically ranges from 4; 9 months; AI-enabled startup tools target 30; 40% reductions through parallelized site identification and contracting.
Related terms
Clinical Trial Startup
Clinical trial startup is the set of activities between protocol finalization and first-patient-in (FPI), including regulatory submissions, IRB/IEC approvals, contract and budget execution, site selection and qualification, central lab and IRT setup, IP labeling, and site initiation visits.
Site Initiation Visit (SIV)
A Site Initiation Visit (SIV) is the formal sponsor-led training and activation visit conducted at each clinical trial site immediately before the site is authorized to begin enrolling participants, typically following IRB approval and contract execution.
Enrollment Rate
Enrollment rate is the average number of participants randomized per active site per month in a clinical trial, used as the principal operational metric of recruitment performance.
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