On Monday, Phio Pharmaceuticals Corp. (NASDAQ:PHIO) stock skyrocketed with a strong session volume of 201.04 million, compared to the average volume of 362.72k, according to data from Benzinga Pro.

Phio reported pathologic responses for patients enrolled in the 2nd cohort, which includes two patients with a complete response or 100% tumor clearance.

Phio’s ongoing Phase 1b clinical study is designed to evaluate the safety and tolerability of neoadjuvant use of intratumoral PH-762 in Stages 1, 2 and 4 cutaneous squamous cell carcinoma, Stage 4 melanoma, and Stage 4 Merkel cell carcinoma.

Of the patients enrolled to date, six patients were diagnosed with cutaneous squamous cell carcinoma, and one patient was diagnosed with metastatic melanoma.

At Day 36 (tumor excision), while patients in the first cohort had stable disease, results are now available for the four patients who completed treatment in the 2nd cohort:

• Complete response (100% tumor clearance) is reported for 2 patients with cutaneous squamous cell carcinoma.
• Partial response (90% tumor clearance) is reported for one patient with cutaneous squamous cell carcinoma and one with stable disease, having not progressed.

No dose-limiting toxicities or clinically relevant treatment-emergent adverse events have occurred in the patients receiving intratumoral PH-762, and the intratumoral injections have been well tolerated.

Preclinical studies demonstrated:

• PH-762 is rapidly taken up by cells and robustly silences PD-1 mRNA and protein in lymphocytes within the tumor microenvironment (TME).
• Intratumoral injection of murine PH-762 (mPH-762) significantly inhibits tumor growth in murine tumor models and is well-tolerated.
• mPH-762-mediated silencing of PH-762 within the TME may generate memory-specific T cells, promoting IFN-γ release in the TME
• Studies in non-human primates demonstrate that PH-762 is well-tolerated and does not induce the release of cytokines associated with cytokine release syndrome.

Price Action: PHIO stock is up 378.7% at $8.09 at the last check on Monday.

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This article Cancer-Focused Phio Pharmaceuticals Stock Gains 300% On Monday - Here's Why originally appeared on Benzinga.com

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