October 3, 2013

Counting Down

In conjunction with Provectus' poster presentation and press release at ECCO 2013, an article entitled Metastatic Melanoma: blistering in PV-10 treatment predicts good outcome appeared on PharmiWeb.com, "Europe's leading industry-sponsored portal for the Pharmaceutical sector, providing the latest jobs, news, features and events listings."

Company principal investigator Dr. Sanjiv Agarwala from St. Luke's Hospital Bethlehem, Pennsylvania provided two substantive quotes:

“The take home message is that if you have injectable tumours and inject them with PV-10 there’s a one in two chance that you will achieve a clinical response, and for these patients an additional one in two chance that a non injected (bystander) lesion will respond.”

“If blistering occurs you can reassure the patient that they’re likely to achieve a good response,” said Dr Agarwala, adding that this effect provided further evidence for an immunological basis for the mechanism of action.

Keep in mind, as the company's press release noted: "PV-10 was only injected intermittently, when tumors were present during the first 16 weeks of the study, in stark contrast to typical clinical studies where treatment is given until either resistance is engendered or patients experience unacceptable toxicity." Bold emphasis is mine.

Intermittently injected, yet PV-10 enabled one in two patients to achieve a clinical response, and for these patients, there was a one in two chance a non-injected lesion responded. I do not think it is difficult to extrapolate results should a Phase 3-like protocol be employed (because the Phase 2 trial presents such results), where such a protocol, currently in use in the compassionate use program, was elaborated upon in Provectus' ESMO 2012 press release: "In the PV-10 arm all cutaneous and subcutaneous lesions will be treated within the first two weeks, with additional treatment allowed every 14 days as necessary to achieve disease control." Bold emphasis is mine.

In the Phase 2 results presented at ECCO, for those subjects where all of their lesions were treated (comprising 28 of 80 trial subjects), complete response (CR) was 50%, partial response was 21%, and stable disease (SD) was 11%. CR + PR = 71%, and loco-regional disease control (CR + PR + SD) was 82%. I imagine achieving near 100% results would not be unreasomable, assuming properly injected lesions, patients remaining with the program, etc.

An interesting line in PharmiWeb article was the last sentence: "Provectus Pharmaceuticals believe they now have sufficient data to seek regulatory approval for PV-10." Management has long believed they've had sufficient data for PV-10 to be approved, but they've never uttered it publicly in press releases or articles such as this.

Peter has not yet responded to my inquiry for comment on the above statement. Craig says Provectus was not its source. It is quite possible the author derived it from interviewing Dr. Agarwala. Maybe she was referring to Agarwala when she wrote back to me "...the company told her this."

Principal investigators often turn to Eric for various information that ultimately makes it way into their quotes or presentations. Consider Agarwala's May 2013 Practical Dermatology article: "There are now data  for longer follow-up periods that show those initial results are holding up." Or, consider Dr. Andtbacka's presentation in April 2013 at the HemOnc Today conference, where he referenced the potential start of a Phase 3 trial (presumably under an SPA). Eric is the source of these information, references and statements, as he very likely was the source this time, whether directly or indirectly (via Agarwala).

Management is pursuing from (requesting of) the FDA approval of PV-10 for Stage IIIb-c patients with locally advanced melanoma and refractory to multiple prior treatments. Refractory means resistant to treatment. This approval is being sought via accelerated or outright approval for this narrow or focused label, more than likely under the umbrella of the Agency's new breakthrough therapy designation. Has the company finally submitted the application?

Given the emergence of the quote -- "Provectus Pharmaceuticals believe they now have sufficient data to seek regulatory approval for PV-10" -- quite possibly.

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