95.5% Pathologic Complete Response with PRV111 Patch Therapy

Privo Technologies, a biopharmaceutical company pioneering localized, minimally invasive therapies for solid tumors, announced unprecedented results from a Phase 2 clinical trial of PRV111, a nanoengineered, cisplatin-releasing patch for the treatment of non-invasive oral cancer and high-grade dysplasia. The trial, known as CLN-004, evaluated PRV111 in 22 patients, achieving a 95.5% pathologic complete response (pCR) rate. This means that in 21 out of 22 evaluable patients, pathology found no cancer cells in the treated area one month after treatment.

The therapy not only cleared the disease but also avoided the need for standard-of-care surgery in all 22 patients. PRV111 successfully downstaged one patient from oral carcinoma in situ (CIS) to low-grade dysplasia, ensuring that no patient required surgical excision. The treated mucosa healed completely, with normal appearance and no scarring, indicating the patch's potential to preserve native tissue function.

The durable responses observed in the trial have been maintained for a median follow-up period of 14 months, with several patients showing ongoing responses beyond 14 months. No recurrences have been observed, and PRV111 demonstrated a well-tolerated profile, with only 85% of treatment-related adverse events being mild and none being serious. Systemic cisplatin exposure remained negligible, highlighting the patch's ability to deliver high concentrations of the drug directly into dysplastic tissue while minimizing systemic side effects.

The CLN-004 study builds upon Privo's earlier clinical experience with PRV111 (CLN-001), which showed promising local tumor responses with no systemic toxicity in a first-in-human setting. These results were published in Nature Communications and highlighted by Forbes for their innovative approach to localized cancer drug delivery.

The current management of non-invasive oral cancer and high-grade dysplasia relies on surgical excision, which is associated with high recurrence rates and morbidity. PRV111 is designed to deliver high concentrations of cisplatin directly into oral lesions and adjacent mucosa through a brief, outpatient procedure, avoiding systemic side effects associated with traditional chemotherapy and standard-of-care surgery.

PRV111 is a nanoengineered, polymeric topical patch that adheres to the lesion, achieving rapid drug permeation into dysplastic tissue and regional lymphatics. The patch is removed after treatment, and the therapy has shown promise in both clinical and preclinical settings.