Provectus Pharmaceuticals (PVCT: Pink Sheets) responded to my column about the obsolescence of its skin cancer drug PV-10 with a "letter to the editor" which was also filed as an 8-K.
Read Provectus' letter closely. It's a non-denial denial which fails to address any of the concerns and questions raised in my column. Provectus executives refuse to explain the delay in starting the phase III study of PV-10 in metastatic melanoma. As I reported, it's been two years since the company told investors that it had completed meetings with FDA and was ready to seek a Special Protocol Assessment (SPA) for the PV-10 phase III study. If PV-10 is such a promising skin-cancer drug, why has Provectus been unable or unwilling to move the drug into a phase III study, as promised?
Provectus also refuses to explain what made the latest meeting with FDA, held Dec. 18, necessary. The company claims an accelerated approval of PV-10 or Breakthrough Therapy designation is being considered. But on what substantive basis? As I reported, the only clinical study conducted with PV-10 in melanoma was completed four years ago and enrolled 80 patients. Does Provectus really expect FDA to consider this tiny study sufficient for an accelerated approval review? How so? Provectus won't say, which speaks volumes.
Let's talk about the Moffitt Cancer Center, which Provectus points to as external validation of PV-10. In its letter Friday, Provectus says this:
Also, counter to Mr. Feuerstein's claim, the Company furnished a great deal of pertinent information through its independent press agent (not spokesperson) Bill Gordon that he failed to include in his article... One announcement, issued by Moffitt Cancer Center on August 22, 2013, highlights how early clinical trials show PV-10 can boost immune response in melanoma tumors, as well as the blood stream.
The "great deal" of pertinent information sent to me by Gordon about PV-10 this week amounted to two press releases, one issued by Provectus, the other by Moffitt Cancer Center. I'm capable of looking up press releases by myself, guys, thanks for nothing.
Provectus misleads investors about the content and significance of the Moffitt Cancer Center press release, which involved a study of PV-10 conducted in mice, not humans. The FDA doesn't approve melanoma drugs with mouse data.
Moffitt is conducting a follow-on study of PV-10 in melanoma patients, but in the year the study has been open for enrollment, Moffitt has managed to recruit only nine of a planned 15 patients, according to Moffitt study coordinator Erica Royster. I spoke with Royster on the phone earlier this morning.
This Moffitt study is designed to assess immunological and blood biomarkers of melanoma lesions injected with PV-10 and will not measure tumor response, progression-free survival or overall survival of the patients enrolled, Royster told me. Moffitt refers to the trial as a "feasibility study." In other words, Provectus will be unable to use this Moffitt study to further demonstrate the efficacy and safety of PV-10 in melanoma patients. Again, FDA doesn't base cancer drug approvals based on immunological response data, particularly from a tiny 15-patient, single center study. [That is, assuming Moffitt can actually complete the study. Enrolling only nine of 15 patients in a year isn't promising.]
By the way, I asked Royster if Moffitt was also recruiting melanoma patients for the phase III studies investigating the checkpoint inhibitors from Merck (MRK) and Bristol-Myers Squibb (BMY):
"Yes, those studies are filling up fast," she said.
-- Reported by Adam Feuerstein in Boston.
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