PRV211 Meets Primary Safety End Point in Invasive Oral Cavity Cancer

PRV211 (intraoperative cisplatin system) met its primary safety end point in patients with invasive oral cavity cancer, according to data from arm 2 of the phase 2/3 CLN-004 trial (NCT05893888). Enrollment for arm 2 was also completed.¹

Findings from the phase 1/2 safety cohort of arm 2 (n = 8) revealed that no treatment-related serious adverse effects, systemic toxicities, or dose-limiting toxicities (DLTs) occurred. Additionally, there were no reports of delayed wound healing or healing complications. Overall, PRV211 was well tolerated per clinical laboratory assessments and post-surgical examinations conducted at the 1-month follow-up visit.

The pharmacokinetic profile assessments of PRV211 indicated negligible systemic platinum absorption and validated targeted delivery with minimal off-target effects. Patients will continue to be monitored for efficacy outcomes, which will be assessed by the rate of locoregional recurrence at 12 months post-surgery.

"Completion of enrollment and achievement of the primary safety end point represent important milestones in the clinical development of PRV211," Manijeh Goldberg, PhD, founder and chief executive officer of Privo Technologies, stated in a news release. "The ongoing follow-up of these patients for locoregional recurrence will help inform the design of future studies as we continue to evaluate PRV211's potential role as a localized, intraoperative treatment approach."

PRV211 is a sterile intraoperative patch intended for integration into standard surgical workflows; it builds on the nanoengineered polymer platform of PRV111.^1,2 The patch is administered immediately following tumor resection and is designed to deliver localized chemotherapy to the surgical bed while minimizing systemic exposure.¹

What are the key design characteristics of CLN-004?

CLN-004 is an open-label study that examined PRV111 and PRV211 for the treatment of patients with oral squamous cell carcinoma.² Arm 1 is evaluating PRV111 in patients with carcinoma-in-situ and included a phase 2/3 run-in. Arm 2 is examining the safety of PRV211 in the intraoperative setting and included a phase 1b dose confirmation portion in patients with T1 to T3, Nx, M0 oral cancer, followed by an expansion phase 2 single-arm portion. To be eligible for both arms, patients must be at least 18 years old, have tumors that are accessible, with no evidence of infection or active bleeding, have disease amenable to surgical resection within 8 weeks of screening, have an ECOG performance status of 2 or less, and have a life expectancy of at least 3 months.

In arm 2, patients have PRV211 placed into the resected tumor bed. The PRV211 system included a liquid permeation enhancer and a cisplatin patch. The permeation was brushed onto the resected tumor bed, and the patch was applied directly over the same area after 5 minutes; up to 2 layers of the PRV211 system were applied to the tumor bed post-resection. PRV211 treatment duration was approximately 10 to 20 minutes at a proposed starting dose of 0.5 mg/cm² of cisplatin.

The primary end point in arm 2 was safety, defined as the incidence of DLTs at 1-month post-surgery and through study completion at approximately 12 months to 14 months. Secondary end points in both arms included event-free survival and pharmacokinetics via platinum levels in blood.

What other data have been reported from CLN-004?

Privo Technologies, the developer of PRV211 announced that the primary efficacy end point was met in arm 1 and that arm 3 was successfully initiated. ¹ A future expansion study is planned to further evaluate the efficacy of PRV211 based on locoregional recurrence outcomes, according to the news release.

References

1. Privo Technologies announces milestone in PRV211 arm of CLN-004 clinical trial: primary endpoint met; no serious adverse events reported. News release. Privo Technologies. January 23, 2026. Accessed February 2, 2026. https://www.prnewswire.com/news-releases/privo-technologies-announces-milestone-in-prv211-arm-of-cln-004-clinical-trial-primary-endpoint-met-no-serious-adverse-events-reported-302668552.html
2. Safety and efficacy study of PRV111 and PRV211 in subjects with oral squamous cell carcinoma. ClinicalTrials.gov. Updated June 15, 2025. Accessed February 2, 2026. https://clinicaltrials.gov/study/NCT05893888