KEY TAKEAWAYS
- The phase 3 trial aimed to investigate the impact of pafolacianine as an intraoperative imaging agent on surgical cytoreduction and its correlation with OS in OC patients.
- Researchers noticed that pafolacianine, with NIRF imaging, enhances intraoperative cancer detection and improves cytoreduction in OC surgery.
The degree of surgical cytoreduction is an independent predictor of overall survival (OS) for ovarian cancer patients.
Janos L. Tanyi and the team aimed to analyze additional data from the Phase 3 trial evaluating the efficacy and safety of pafolacianine sodium injection (OTL38) as an intraoperative real-time fluorescent imaging agent to detect cancer during cytoreductive surgery.
Researchers performed an inclusive analysis within this phase 3 single-dose, open-label trial, further investigating malignant fluorescent lesions removed from ovarian cancer patients scheduled for cytoreductive surgery across 11 tertiary care centers (J Clin Oncol 2023 Jan 10;41(2):276-284).
The original study confirmed the efficacy and safety of OTL38 (0.025 mg/kg i.v., ≥1 h prior to imaging) in combination with intraoperative near-infrared fluorescence (NIRF) imaging to detect additional lesions not detected by palpation and normal white light alone. The objectives of this current investigation were to evaluate the timing of malignant lesion identification by fluorescent imaging and assess whether these fluorescent lesions were suitable for surgical removal.
About 178 patients were enrolled, with 150 receiving the full OTL38 dose, and 134 randomized to NIR imaging (Intent To Treat), while 109 folate receptor-positive patients comprised the full analysis set (FAS). During surgeries, 395 malignant lesions were fluoresced and removed, with 318 identified under both white light and fluorescence.
The study identified 77 lesions, from 46 patients, solely by fluorescence, with 46 of these lesions (59.7%) discovered after surgery under white light was completed and the area was scanned again before closure. In the FAS population, 33.0% (95% CI, 24.3 to 42.7) had at least one additional evaluable FR-positive ovarian cancer lesion confirmed by central pathology, and 27% (95% CI, 19.6 to 35.2) in the ITT population.
Surgeons reported changing the pre-fluorescence surgical plan for 56% of patients. For 55 (51%) patients, imaging with OTL38 helped achieve more complete debulking, with R0 achieved 62.4% overall. Surgeons did not remove all identified lesions in 15% (surgeon only), 11% (both surgeon and OTL38 identified), and 5.5% (fluorescence only) of patients during the initial surgery and prior to closing.
The study concluded that pafolacianine, in combination with NIRF imaging, successfully met its primary endpoint by intraoperatively identifying additional cancer in 33% of patients. The detection of significant lesions after surgery completion underscores its potential as a real-time adjunct in surgical imaging, enhancing ovarian cancer cytoreduction.
The study was sponsored by On Target Laboratories, LLC.
Source: https://sgo.planion.com/Web.User/AbstractDet?ACCOUNT=SGO&ABSID=460342&CONF=AM2024&CKEY=
Clinical Trial: https://clinicaltrials.gov/study/NCT03180307
Tanyi J L., Randall L M., Chambers S K., et al. (2024). “Further analysis of phase III, single-dose, open-label study to investigate the efficacy of pafolacianine sodium injection (OTL38) for intraoperative imaging during cytoreductive surgery of folate receptor-positive ovarian cancer (NCT03180307).” Presented at SGO 2024.
