Provectus Pharmaceuticals publishes article on novel treatment for metastatic melanoma

Provectus Pharmaceuticals, Inc. (OTC BB: PVCT), a development-stage oncology and dermatology biopharmaceutical company, announces the publication of an article, entitled “A novel treatment for metastatic melanoma with intralesional rose bengal and radiotherapy: a case series," authored by Dr. Matthew C. Foote, Dr. Bryan H. Burmeister, Janine Thomas, and Dr. B. Mark Smithers, in the current issue of the peer-reviewed journal, Melanoma Research (20(1):48-51, February 2010).

“Three patients with metastatic melanoma were treated with intralesional rose bengal followed by external beam radiotherapy. In all cases patients had an impressive response without significant increase in acute radiation reaction.”

The article is based on the authors’ observations while treating patients previously enrolled in the ongoing Phase 2 clinical trial of PV-10 for metastatic melanoma. PV-10 is Provectus’ formulation of rose bengal for intralesional (IL) injection into solid tumors. The authors stated, “Three patients with metastatic melanoma were treated with intralesional rose bengal followed by external beam radiotherapy. In all cases patients had an impressive response without significant increase in acute radiation reaction.” A copy of the article can be accessed at the following link: http://www.pvct.com/melanoma_update.html

The patients cited in the article were part of the Phase 2 study investigating the effectiveness of PV-10 for locoregional treatment of metastatic melanoma. The authors said, “All of the impressive responses occurred in previously injected lesions, non-injected lesions and other lesions that developed in the local area, which may have been exposed to rose bengal.”

The authors continued, “Although a range of [radiation] dose and fractionation schedules were used in these cases, the responses that were noted after radiotherapy, even for large volume disease, after IL rose bengal were significantly more than our experience would have predicted with all three of the patients treated having a complete in-field response.”

“There are several radiobiological rationales that may explain our observation including radiosensitization by the rose bengal, additive cell kill or augmentation of the host immune response by the interaction of the two modalities. As radiation was applied many weeks after rose bengal dosing, and effects also occurred in new lesions not present when rose bengal was administered, this phenomenon may not arise solely from conventional radiosensitization,” added the authors.

Craig Dees, Ph.D., President and CEO of Provectus said, “Each of the patients cited in this article were part of the Phase 2 clinical study prior to subsequent radiation therapy, and had aggressive cases of metastatic melanoma. Because the Phase 2 study protocol limited the investigator’s dosing options, Dr. Smithers and his team were not able to match the allowed dosing regimen to the natural disease course for these patients. Six to 12 weeks after receiving their final PV-10 dose, the patients received supplemental radiotherapy that led to the remarkable responses noted in the article. Dr. Smithers is now part of our compassionate use program for PV-10 which allows far more flexibility in dosing, and we look forward to assessing results from this program and their implications for optimizing how PV-10 is administered to metastatic tumors. We also anticipate additional studies to confirm these initial observations using PV-10 in conjunction with radiotherapy.”