Pafolacianine for intraoperative molecular imaging of cancer in the lung: The ELUCIDATE trial

Objective: The study objective was to determine the clinical utility of pafolacianine, a folate receptor-targeted fluorescent agent, in revealing by intraoperative molecular imaging folate receptor α positive cancers in the lung and narrow surgical margins that may otherwise be undetected with conventional visualization.

Methods: In this Phase 3, 12-center trial, 112 patients with suspected or biopsy-confirmed cancer in the lung scheduled for sublobar pulmonary resection were administered intravenous pafolacianine within 24 hours before surgery. Participants were randomly assigned to surgery with or without intraoperative molecular imaging (10:1 ratio). The primary end point was the proportion of participants with a clinically significant event, reflecting a meaningful change in the surgical operation.

Results: No drug-related serious adverse events occurred. One or more clinically significant event occurred in 53% of evaluated participants compared with a prespecified limit of 10% (P < .0001). In 38 participants, at least 1 event was a margin 10 mm or less from the resected primary nodule (38%, 95% confidence interval, 28.5-48.3), 32 being confirmed by histopathology. In 19 subjects (19%, 95% confidence interval, 11.8-28.1), intraoperative molecular imaging located the primary nodule that the surgeon could not locate with white light and palpation. Intraoperative molecular imaging revealed 10 occult synchronous malignant lesions in 8 subjects (8%, 95% confidence interval, 3.5-15.2) undetected using white light. Most (73%) intraoperative molecular imaging-discovered synchronous malignant lesions were outside the planned resection field. A change in the overall scope of surgical procedure occurred for 29 of the subjects (22 increase, 7 decrease).

Conclusions: Intraoperative molecular imaging with pafolacianine improves surgical outcomes by identifying occult tumors and close surgical margins.