Showing posts with label PV-10. Show all posts
Showing posts with label PV-10. Show all posts

March 24, 2017

"Provectus Biopharmaceuticals Announces Terms Of Definitive Financing Commitment"

♢♢ Note: I and others entered into a securities transaction with Provectus in March 2017. Please see the Blog's Disclosures page and/or refer Provectus' Securities and Exchange Commission filings for further, future disclosures.

The source link of Provectus' March 23rd press release related to my and others' securities transaction and involvement with the Company (reproduced below) is here. Also see the Disclaimer to the right, and the blog's Disclosures page.

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KNOXVILLE, Tenn., March 23, 2017 /PRNewswire/ -- Provectus Biopharmaceuticals, Inc. (OTCQB: PVCT, www.provectusbio.com) ("Provectus" or the "Company"), a clinical-stage oncology and dermatology biopharmaceutical company, today disclosed terms of the previously announced Definitive Financing Commitment Term Sheet (the "Definitive Financing") it entered into on March 19 with a group of the Company's stockholders, who are referred to in the Definitive Financing as "PRH Group" in a Form 8-K filed with the Securities and Exchange Commission.

The members of PRH Group include Edward Pershing (serving exclusively in an advisory capacity only); Dominic Rodrigues and Bruce Horowitz, who were previously named as special advisers to the Board of Directors of Provectus ("the Board") on February 23; and additional members as the PRH Group may determine at its sole discretion.

Under the Definitive Financing, PRH Group would undertake best efforts to arrange for a financing of a minimum of $10 million and a maximum of $20 million, which would be provided to Provectus in several tranches.  The structure of the Definitive Financing takes the form of a secured loan that would convert into a new series of preferred stock with a liquidation preference upon the sale, dissolution or liquidation of the Company, a conversion into common stock that prices one common share at approximately $0.29, and customary voting rights on an as-converted basis.

Within the next 30 days or sooner, a total of $5 million will be made available to the Company, comprised of the acceleration of the remainder of the $2.5 million from the previously announced promissory note issued to Eric Wachter, Ph.D., co-founder and Chief Technology Officer and an additional $2.5 million from PRH Group. Once funded, the $5 million will become secured convertible promissory notes from the Company to each Investor.

Three current members of the Board will resign simultaneously upon the PRH Group's funding of the $2.5 million tranche into escrow, and PRH Group will nominate three new directors for approval by and appointment to the Board.  Additionally, the Company has agreed that, as soon as practicable after the funding of the second tranche of the financing, in which PRH Group intends to raise an additional $5 million by June 30, 2017, the two remaining current Board members will resign and be replaced by two new directors appointed to and approved by the Board.

PRH Group is joining with the Company to expand its current search for additional executives with biotechnology and pharmaceutical industry experience, including but not limited to a new Chief Executive Officer.

Dominic Rodrigues said, "PRH Group believes the fundamentally strong value of Provectus' asset base and intellectual property has attracted the initial interest of highly qualified managerial talent.  As the Company reestablishes a sound financial foundation, PRH Group is confident that Provectus will be well positioned to hire talented and experienced executives and managers. We are delighted to be a part of Provectus' evolution as a biopharmaceutical company by guiding its advancement of clinical development programs to develop vitally needed new treatments to help cancer patients."

About Provectus

Provectus is a clinical-stage biopharmaceutical company developing new therapies for the treatment of solid tumor cancers and dermatologic diseases. Provectus' investigational oncology drug, PV-10, is an oncolytic immunotherapy currently enrolling patients in Phase 3 clinical trials for metastatic melanoma. The Company has received orphan drug designations from the FDA for its melanoma and hepatocellular carcinoma indications. PH-10, its topical investigational drug, has completed Phase 2 clinical trials as a treatment for atopic dermatitis and psoriasis. Information about these and the Company's other clinical trials can be found at the NIH registry, www.clinicaltrials.gov. For additional information about Provectus, please visit the Company's website at www.provectusbio.com or contact Allison + Partners.

FORWARD-LOOKING STATEMENTS: This release contains "forward-looking statements" as defined under U.S. federal securities laws. These statements reflect management's current knowledge, assumptions, beliefs, estimates, and expectations and express management's current views of future performance, results, and trends and may be identified by their use of terms such as "anticipate," "believe," "could," "estimate," "expect," "intend," "may," "plan," "predict," "project," "will," and other similar terms. Forward-looking statements are subject to a number of risks and uncertainties that could cause our actual results to materially differ from those described in the forward-looking statements. Readers should not place undue reliance on forward-looking statements. Such statements are made as of the date hereof, and we undertake no obligation to update such statements after this date.

Risks and uncertainties that could cause our actual results to materially differ from those described in forward-looking statements include those discussed in our filings with the Securities and Exchange Commission (including those described in Item 1A of our Annual Report on Form 10-K for the year ended December 31, 2015, as supplemented by those described in Part II, Item 1A of our Quarterly Report on Form 10-Q for the quarter ended September 30, 2016) and the following:
  • Provectus' potential receipt of sales from PV-10 and PH-10, transaction fees, licensing and royalty payments; payments in connection with the Company's liquidation, dissolution or winding up, or any sale, lease, conveyance or other disposition of any intellectual property relating to PV-10 or PH-10;
  • our ability to raise additional capital if we determine to commercialize PV-10 and/or PH-10 on our own;
  • our ability to close on an equity financing from PRH; and
  • whether our securities remain listed on the NYSE MKT.

February 13, 2017

February 2, 2017

"Colon cancer cell treatment with rose bengal generates a protective immune response via immunogenic cell death"

Article source link is here.
Click to enlarge.
"Abstract:
Immunotherapeutic approaches to manage patients with advanced gastrointestinal malignancies are desired; however, mechanisms to incite tumor-specific immune responses remain to be elucidated. Rose bengal (RB) is toxic at low concentrations to malignant cells and may induce damage-associated molecular patterns; therefore, we investigated its potential as an immunomodulator in colon cancer. Murine and human colon cancer lines were treated with RB (10% in saline/PV-10) for cell cycle, cell death, and apoptosis assays. Damage-associated molecular patterns were assessed with western blot, ELISA, and flow cytometry. In an immunocompetent murine model of colon cancer, we demonstrate that tumors regress upon RB treatment, and that RB induces cell death in colon cancer cells through G2/M growth arrest and predominantly necrosis. RB-treated colon cancer cells expressed distinct hallmarks of immunogenic cell death (ICD), including enhanced expression of calreticulin and heat-shock protein 90 on the cell surface, a decrease in intracellular ATP, and the release of HMGB1. To confirm the ICD phenotype, we vaccinated immunocompetent animals with syngeneic colon cancer cells treated with RB. RB-treated tumors served as a vaccine against subsequent challenge with the same CT26 colon cancer tumor cells, and vaccination with in vitro RB-treated cells resulted in slower tumor growth following inoculation with colon cancer cells, but not with syngeneic non-CT26 cancer cells, suggesting a specific antitumor immune response. In conclusion, RB serves as an inducer of ICD that contributes to enhanced specific antitumor immunity in colorectal cancer."
"Discussion:
...In the current study, we have provided several lines of evidence demonstrating that RB exhibited pronounced direct cytotoxicity in colorectal cancer cells both in vivo and in vitro. Our data also confirmed RB-induced prominent cell growth arrest at the G2/M phase and predominant necrotic cell death that was partially dependent on lysosome function. Furthermore, the findings from the current study identified that RB promoted expression of hallmarks related to ICD in colon cancer cell lines. Vaccination with RB-treated colon cancer cells and intralesional tumor injection resulted in retardation in tumor growth or prevention of subsequent tumor formation following challenge with the same tumor cells. These findings show that RB may serve as an inducer of ICD that contributes to enhanced specific antitumor immunity in colorectal cancer. Additional studies are warranted to elucidate the therapeutic potential of RB-induced ICD."

January 1, 2017

Rose Bengal (PV-10); The Glocalization of Cancer Treatment: "Act Locally, Think Globally"

Wikipedia's glocalization page notes:
"Glocalization (a portmanteau of globalization and localization) is the adaptation of international products around the particularities of a local culture in which they are sold. The process allows integration of local markets into world markets. 
The term first appeared in a late 1980s publication of the Harvard Business Review. At a 1997 conference on "Globalization and Indigenous Culture", sociologist Roland Robertson stated that glocalization “means the simultaneity – the co-presence – of both universalizing and particularizing tendencies.”"
An intellectually honest treatment of intralesional or intratumoral delivery of immunotherapy frames the work of more than 100 years ago of Dr. William Coley, MD, "now considered the “Father of Cancer Immunotherapy”" in terms of both route of delivery (intralesional or intratumoral, as opposed to orally or intravenously), and what is delivered (dead bacteria).

See Do Dr. Jedd Wolchok/Sloan Kettering Understand Immunotherapy's History? (July 12, 2016) on the blog's Archived News VI page.

It would appear that Memorial Sloan Kettering Cancer Center (MSKCC) recently (i.e., that is 2015, perhaps earlier) embraced the history of the medical institution's involvement with harnessing the immune system to fight and treat cancer by describing the work of Dr. William Coley, MD, "now considered the “Father of Cancer Immunotherapy,”" on its website. See MSKCC webpage "Immunotherapy: Revolutionizing Cancer Treatment since 1891." Dr. Coley began his career as a bone surgeon at New York Cancer Hospital, which later became part of MSKCC.

When writing about immunotherapy, and usually pointing to Bristol-Myers' anti-CTLA-4 drug ipilimumab (Yervoy) and/or anti-PD-1 drugs pembrolizumab (Merck & Co., Keytruda) and nivolumab (Bristol-Myers, Opdivo), many mainstream media and medical writers and journalists often include in their introduction descriptions of Dr. Coley's work. I think it makes for a good story, as the writers endeavor to link history, and descriptions and lessons from the past, to the present day, and potentially our future.

MSKCC says Dr. Coley's work "paved the way for the modern immunotherapies that are helping patients today."

Route of delivery matters. Dr. Coley's work, and his approach to treatment, comprise two key feature, one of which nearly all who write about him (but not everyone) routinely ignore, conflating his discoveries, observations and conclusions with drugs incapable of delivering what he experimented with in order to seek better patient outcomes.

Coley's approach to the treatment of cancer was composed of (a) a "drug compound," the heated-killed bacteria known as Coley’s toxins whose actions following treatment somehow engaged the immune system (e.g., fever), and (b) the route of administration by injection of the dead bacteria into the patient's tumors.

The key feature of Coley's work that is ignored, conflated, confused or misunderstood: the manner in which the drug, drug compound, biologic or small molecule is delivered. Yervoy, Keytruda and Opdivo are immunotherapies that are intravenously administered to patients; they are not injected into patient tumors.

Google "Wolchok" and "Coley," and thousands of results are returned. MSKCC's Dr. Jeff Wolchok, a medical oncologist, apparently uses Coley's story when he (Dr. Wolchok) explains immunotherapy. Dr. Wolchok, holder of MSKCC's Lloyd J. Old Chair for Clinical Investigation, was a student of Dr. Lloyd Old, MD, who (according to Memorial Sloan Kettering):
"...did some of the first modern research on immunotherapy, with a substance called BCG, now an FDA-approved treatment for bladder cancer. BCG is made from a weakened version of the bacterium that causes tuberculosis. Experts think Coley’s toxins may have worked in a similar manner to BCG — jumpstarting an immune response to cancer by provoking one against the bacteria."
This work of Dr. Old appears to be during the 1950s. For example, see "Effect of Bacillus Calmette-Guérin Infection on Transplanted Tumours in the Mouse." Who am I to say or write this, but perhaps Dr. Old was focused on one of the two key features, the use of a biologic (i.e., the "drug compound") to engage the immune system. He may have ignored Coley's work's other feature, route of delivery.

The administration of BCG (aka Bacillus Calmette-Guérin) for bladder cancer is intravesical, which means it is "put directly into the bladder through a catheter, instead of being injected into a vein or swallowed." See the illustration below.
Image source
Intravesical, like intravenous is not injection into the tumor (i.e., intralesional, intratumoral).

Ironically, the second aspect of Coley's work, route of delivery, was explored in the 1970s with BCG (or BCG immunotherapy) in metastatic melanoma when the drug was it was directly injected into metastatic melanoma lesions limited to the skin; see, for example, "BCG Immunotherapy of Malignant Melanoma: Summary of a Seven-year Experience." Unfortunately, the immunotherapy failed a Phase 3 trial; see 2004 paper "Mature results of a phase III randomized trial of bacillus Calmette–Guerin (BCG) versus observation and BCG plus dacarbazine versus BCG in the adjuvant therapy of American Joint Committee on Cancer Stage I–III melanoma (E1673):"
"In what to our knowledge is the largest ever trial to test the role of BCG as adjuvant therapy for melanoma, no benefit for BCG was observed for patients with AJCC Stage I–III disease. The mature results of the current trial projected to 30 years confirmed the negative results of previous smaller studies utilizing this agent."
What does Dr. Coley's work tell us about how to treat cancer via immunotherapy? Is it about the drug compound? Is it about the route of administration? Or, as I believe (because of Rose Bengal), is it both?

Consider April 2016's "Germ of an Idea: William Coley's Cancer-Killing Toxins", which more appropriately places Dr. Coley's work into context:
"That was all Coley needed to proceed directly to human trials, and Zola would become his first test subject. Coley filled a syringe with living Streptococcus pyogenes, known to induce erysipelas attacks, and injected the solution directly into Zola’s tumor. It took awhile — in fact, it took repeated injections over five months — but finally, an hour after one particular injection in October, Zola broke out into sweaty chills, and his body temperature soared to 105 degrees... 
“Coley injected his first patient a century ago, and what he saw was almost identical to what we saw in our first patient,” says Saurabh Saha, a partner with Atlas Venture, former BioMed Valley researcher and senior author of the study...” 
C. novyi is really a two-pronged weapon against cancer: It germinates in tumors and releases cancer-killing enzymes, and it may also trigger an immune response similar to Coley’s Toxin. Since C. novyi survives only in oxygen-poor environments — tumors can be notoriously void of oxygen — the bacteria die when they reach healthy, oxygen-rich tissues, sparing collateral damage. Essentially, the injections perform highly precise biosurgery from the inside out."
Updated (7/31/16): Does The New York Times understand cancer immunotherapy's history? The NYT's Denise Grady wrote "Harnessing the Immune System to Fight Cancer" on July 30th. In it she references Dr. Coley's name 18 times, and presumably uses his work as a vehicle to discuss Dr. James Allison's immune checkpoint inhibitor work. Interestingly, this author, while invoking Coley's biologic material he injected into patients, does not mention the route of delivery Coley used. She uses the verb "inject," but does not say where:
"Dr. Coley began to inject terminally ill cancer patients with Streptococcal bacteria in the 1890s. His first patient, a drug addict with an advanced sarcoma, was expected to die within weeks, but the disease went into remission and he lived eight years. 
Dr. Coley treated other patients, with mixed results. Some tumors regressed, but sometimes the bacteria caused infections that went out of control. Dr. Coley developed an extract of heat-killed bacteria that came to be called Coley’s mixed toxins, and he treated hundreds of patients over several decades. Many became quite ill, with shaking chills and raging fevers. But some were cured."
Ironically, she references radiation, which is making a resurgence because of the growing understanding/belief that local treatments to/on tumors may unlock the gateway to the immune system's reaction around the body:
"Early in the 20th century, radiation treatment came into use. Its results were more predictable, and the cancer establishment began turning away from Coley’s toxins. Dr. Coley’s own institution, Memorial Hospital (now Memorial Sloan Kettering Cancer Center) instituted a policy in 1915 stating that inpatients had to be given radiation, not the toxins. Some other hospitals continued using them, but interest gradually waned. Dr. Coley died in 1936."
See, for example, June 2015's "June Podcast: The Abscopal Effect with Sandra Demaria."

Finally, it is interesting to note that Allison, Wolchok and others submitted a patent application (published in 2014) for the use of an oncolytic virus with immune checkpoint inhibitors via the injection of the virus into tumors.

Which brings us back to glocalization in cancer treatment...

H/t @bradpalm1:
Tweet image source
Click to enlarge.
Abstract:
Immune mechanisms have evolved to cope with local entry of microbes acting in a confined fashion but eventually inducing systemic immune memory. Indeed, in situ delivery of a number of agents into tumors can mimic in the malignant tissue the phenomena that control intracellular infection leading to the killing of infected cells. Vascular endothelium activation and lymphocyte attraction, together with dendritic cell–mediated cross-priming, are the key elements. Intratumoral therapy with pathogen-associated molecular patterns or recombinant viruses is being tested in the clinic. Cell therapies can be also delivered intratumorally, including infusion of autologous dendritic cells and even tumor-reactive T lymphocytes. Intralesional virotherapy with an HSV vector expressing GM-CSF has been recently approved by the Food and Drug Administration for the treatment of unresectable melanoma. Immunomodulatory monoclonal Abs have also been successfully applied intratumorally in animal models. Local delivery means less systemic toxicity while focusing the immune response on the malignancy and the affected draining lymph nodes. The Journal of Immunology, 2017, 198: 31–39.
"Intratumoral Delivery of Immunotherapy-Act Locally, Think Globally," Aznar et al., J Immunol. 2017 Jan 1;198(1):31-39.

The article does not mention or reference PV-10. Nevertheless, the notion of concept of local delivery of immunotherapy is important, and the authors do reference oncolytic virus (OV) immunotherapy or oncolytic immunotherapy T-Vec -- "Intralesional virotherapy with an HSV vector expressing GM-CSF has been recently approved by the Food and Drug Administration for the treatment of unresectable melanoma."

The introduction of the article frames Coley's work in context:
"More than 100 years ago, the surgeon William Coley found that in some cases of soft tissue sarcoma there were regressions following erysipelas. Facing similar cases in his practice, he proceeded to cause such risky infections on purpose, observing some successful responses. To make it safer he went on to use bacterial-derived material (Coley’s toxins) to locally inject tumor masses. Since then, we have learned that the results obtained by Coley were related to a systemic antitumor immune response following local delivery of the ill-defined microorganisms and bacterial toxins."
Provectus CTO Dr. Eric Wachter, PhD noted the interest in the field of intralesionally delivered cancer medicines in his November 14th slide presentation:
Click to enlarge
The challenge or opportunity for intralesional or intratumoral delivery, however, is the beneficial power -- both breadth and depth -- of the immunological signalling generated subsequent to tumor injection with the compound in question.

Aznar et al. note as much:
"There are a number of immune mechanisms to be exploited by local delivery that would mimic infection by a pathogen (Fig. 1). The key aspect is that local intervention needs to exert systemic effects against distant metastases based on lymphocyte recirculation. The difficulty in achieving systemic effects would depend on factors such as proximity, similar lymphatic drainage, vascularization or truly anatomical distance. In tumor vaccination, it has been observed that the site of priming imprints recirculation patterns to T cells. This cellular behavior is dependent on chemokine and tissue homing receptors. Interestingly, DCs in each territory imprint the pattern of recirculation receptors to the T cells that they prime by cognate Ag presentation."
Click to enlarge. Part 1 of 2 of full image. Figure 1, Aznar et al.
Click to enlarge. Part 2 of 2 of full image. Figure 1, Aznar et al.

December 22, 2016

Rose Bengal (PV-10): HCC, Colorectal liver mets

Provectus issued a press release today regarding its clinical liver cancer work, "Announces Two Poster Presentations on PV-10 for Liver Tumors." As of this writing no associated 8-K was filed.

The press release highlighted two abstracts and upcoming [poster, presumably] presentations of results from the company's ongoing liver Phase 1 trial, which has evolved into (a) a "basket study" treating patients with and collecting data on a range of tumor types affecting the liver, and (b) a study of hepatocellular carcinoma (HCC) (primary liver cancer).

Results from patients with colorectal cancer that has metastasized to the liver, and treated with PV-10 (Rose Bengal) will be presented at the 2017 Symposium on Clinical Interventional Oncology (CIO) (CIO) on February 4-5 in Hollywood, Florida. These data should comprise results from at least 5 patients (see the slide from Provectus' November 14th 3Q16 business update call below). The title of the abstract is "Percutaneous Rose Bengal as an Ablative Immunotherapy for Hepatic Metastases," with my underlined emphasis.

Results from patients with HCC, and treated with PV-10 (Rose Bengal), the original goal or initial phase of the liver Phase 1 study, will be presented at the 26th Conference of the Asian Pacific Association for the Study of the Liver (APASL) on February 15-19 in Shanghai, China. These data should comprise results from the original/initial patients (see the slide below). The title of the abstract is "Intralesional Rose Bengal as an Ablative Immunotherapy for Hepatic Tumors," with my underlined emphasis.
Click to enlarge.
Initial liver data was presented in Barcelona, Spain and Osaka, Japan in July 2015, "Phase 1 Study of PV-10 for Chemoablation of Hepatocellular Cancer and Cancer Metastatic to the Liver." Note the absence of the word "immunotherapy" in the abstract/poster's title.

December 8, 2016

Rose Bengal (PV-10) + Oncology + Pediatrics

Updated below: 12/8/16 and 12/15/16.

Provectus issued a press release and filed an associated 8-K today regarding a collaboration (currently, an "agreement to establish a framework for collaborative pre-clinical research projects") to explore the use of Rose Bengal/PV-10 in pediatric cancer, Announces Agreement with POETIC (Pediatric Oncology Experimental Therapeutics Investigators Consortium) to Study Potential of PV-10 for Pediatric Cancer.

Image source
POETIC's website is here. POETIC co-founder Dr. Tanya Trippett, MD (Memorial Sloan Kettering Cancer Centerattended April healthcare conference at the Vatican, where Australia's Peter MacCallum Cancer Centre's Dr. Grant McArthur discussed PV-10.

See Infantile (July 26, 2016) on the blog's Archived News VI page:
"There also is a robust library of biomedical literature experimenting on/with, describing and discussing Rose Bengal's diagnostic applications in adults, and notably in children. See, for example October 15, 2015 blog post Still Standing, or Rose Bengal in children (hepatoblastoma, radiopharmaceutical) (May 6, 2016) on the blog's Archived News V page. In medicine, children are not small adults when it comes to safety, efficacy, dosing, etc. Most of the pediatric literature related to Rose Bengal refers to the API as liver function diagnostic 131I-Rose Bengal. From a safety and PK perspective, it is interesting, available for review, and dates back to at least the 1960s."
See also October 15, 2015 blog post Still Standing:
"Rose Bengal’s medical properties have been established in the clinic, adults and children[5], and the literature, as well as with the FDA. The compound was noted as a stain for visualizing corneal ulcers in 1919[6] and a marker for impaired liver function in 1923[7]. Currently there are more than 3,800 Rose Bengal references in the U.S. National Institutes of Health's National Library of Medicine’s PubMed Central database.[8] The compound has [non-therapeutic] FDA safety profiles as an intravenous hepatic diagnostic called Robengatope® and a topical ophthalmic diagnostic called Rosettes® or Minims®."
Updated (12/8/16).1: Additional Information & Takeaways
  • I'm led to believe MSKCC (Memorial Sloan Kettering Cancer Center) [on the pediatric oncology side] began using reagent grade Rose Bengal (i.e., drug substance, or the active pharmaceutical ingredient [API] in PV-10; e.g., available from Sigma-Aldrich) -- presumably in in vitro models -- in the spring (following the above mentioned Vatican healthcare conference). Apparently, PV-10 (i.e., pharmaceutical grade drug product) was shipped to MSKCC and other POETIC partners (specifically, I would imagine to Alberta Children's Hospital, which will lead the pre-clinical development of another POETIC collaboration; see CorMedix below).
  • I also imagine POETIC and others' treatment approach to pediatric cancer patients may mirror the approach being taken with adult cancer patients in the current"age," "era" or time of immuno-oncology; that is, combination of PV-10 with checkpoint inhibition.
Updated (12/15/16).2: "Copyright infringement?" Yuck, yuck...
Click to enlarge. Tweet image source
Provectus' attendance link is here:

    November 23, 2016

    Oncolytic

    Source of tweet image below: Paul D. Rennert (@PDRennert).
    Click to enlarge
    On the SITC slide above, I imagine PV-10 (in combination with a/the PD/PDL1 "backbone") would fall under "oncolytic" in the pembrolizumab column (second from the left). The slide clearly illustrates an amazing amount of work underway to augment this fundamental concept of combination therapy or treatment in cancer.

    The slide reinforces an important theme of Provectus' Dr. Eric Wachter, PhD's November 14th presentation (as part of the 3Q16 business update call): there is considerable interest and clinical activity in melanoma, and while he believes there is no doubt about the relevance of PV-10, cutting through the crowd to the front of the pack will require continued effort on Provectus' part. See, for example, the slides below from his presentation:
    Click to enlarge
    Click to enlarge
    Under Additive: 1 + 1 < 2. Synergistic: 1 + 1 > 2 (best case, >> 2) (June 25, 2016) on the blog's Archived News VI page I co-opted a slide from MD Anderson's Dr. Merrick Ross, MD's presentation -- see ASCO 2016: "The Role of Immunotherapy in the Medical Management of Melanoma: An Overview for the Oncologist" (June 22, 2016) -- that provided results from various combination therapy studies for advanced or metastaic melanoma slide in order illustratively model the difference between additivity and synergism:
    Click to enlarge
    The table above was updated to include recent combination therapy data of oncolytic virus CVA21 (Coxsackievirus A21, a cold virus) and anti-PD-1 drug pembrolizumab (Keytruda) presented at SITC 2016: "According to the preliminary data from the first 10 patients evaluable for best overall tumour response assessment, a disease control rate (DCR) of 100 percent (10/10 patients) was demonstrated, including seven patients (70 percent) with an objective tumour response and three patients (30 percent) with stable disease" {Viralytics’ CAVATAK™ in Combination with KEYTRUDA® Provides Promising Results in Advanced Melanoma from the CAPRA 1b study}.

    Interestingly, however, Viralytics' combination therapy above yielded no complete responses in its Best irRC Overall Response (see the SITC poster here), and did not use RECIST 1.1 in its tumor response measurement. Median doses of CVA21 and pembrolizumab (for the ten patients noted above) were 8 (range 6-11) and 6 (3-11), respectively. CVA21, like T-Vec, has to be delivered often for its effect to manifest, weak or weaker (than PV-10's immunologic signalling) as it is.

    Viralytics previously established a collaboration with Merck & Co. in November 2015 to combine CVA21 and pembro in either advanced stage non-small cell lung cancer (NSCLC) or metastatic bladder cancer. In June 2016 the parties initiated a Phase 1b study, one-site (Australia) program for NSCLC where CVA21 would be delivered intravenously (three different dosing levels of CVA21), and not intralesionally or intratumorally.

    In his November 21st article "Viralytics' anticancer virus aces checkpoint inhibitor combo trials," FierceBiotech's Phil Taylor provides or references several examples of funded or acquired oncolytic virus companies:

    • 2011: Amgen's acquisition of BioVex (U.S.), and thus T-Vec (Imlygic) (formerly OncoVEX) ($1 billion: $425 million upfront and a $575 million earn out), which was approved in 2015,
    Edison Investment Research's Dennis Hulme and Lala Gregorek's November 21st equity research note on Viralytics entitled "Cavatak data continue to impress" presents the valuation rationale below:
    Click to enlarge.
    "Notable changes in immune cell infiltrates and expression of PD-L1 within the CVA21-treated NMIBC tissue were also observed. Increased urinary levels of the chemokine, HMGB1, was observed in six of eleven patients following exposure to CVA21."
    Moffitt Cancer Center noted increased HMGB1 levels in sera of melanoma patients after intralesional PV-10 treatment.
    Click to enlarge. Image source
    Moffitt did not report the number of patients with elevation, but rather the change in mean. Inspection of Figure 6 in Liu et al. suggests most patients (n = 14) exhibited increased HMGB1.

    Oncolytic, as a label or category, can be somewhat deceiving.

    Intralesional (IL) oncolytic virus (e.g., T-Vec, CVA21, HF10, etc.) is different than IL chemical small molecule (i.e., PV-10), both of which might be referred to as oncolytic immunotherapy.

    Oncolytic virus immunotherapy however delivered (e.g., intralesionally/intratumorally, intravenously) is different from ablative immunotherapy (i.e., PV-10).

    Takeaway: There's a real opportunity for Provectus and PV-10. There is no doubt about the relevance of PV-10, but cutting through the crowd to the front of the pack will require continued effort on the company's part.

    November 8, 2016

    SITC 2016, ABSTRACT: Intralesional injection with Rose Bengal and systemic chemotherapy induces anti-tumor immunity in a murine model of pancreatic cancer

    Updated below: 11/8/16 {thrice}.

    Source link

    Intralesional injection with Rose Bengal and systemic chemotherapy induces anti-tumor immunity in a murine model of pancreatic cancer

    Shari Pilon-Thomas, Amy Weber, Jennifer Morse, Krithika Kodumudi, Hao Liu, John Mullinax, Amod A Sarnaik H. Lee Moffitt Cancer Center, Tampa, FL, USA

    Journal for ImmunoTherapy of Cancer 2016, 4(Suppl 1):P256

    Background
    Rose Bengal is a xanthene dye that has been utilized for liver function studies and is currently used topically in ophthalmology. Intralesional (IL) Rose Bengal (PV-10) has been shown in murine models and melanoma clinical trials to induce regression of treated melanoma lesions and uninjected bystander lesions. This study was undertaken to measure whether IL PV-10 can induce systemic anti-tumor effects alone or in combination with gemcitabine (Gem) therapy in a murine model of pancreatic cancer.

    Methods
    C57BL/6 mice received Panc02 pancreatic tumor cells subcutaneously (SC) on one flank to establish a single tumor. On day 7, tumor was treated with IL PV-10. Control mice received IL phosphate
    buffered saline (PBS). Tumor growth was measured. Splenic T cells were collected and co-cultured with Panc02 or irrelevant B16 cells. Supernatants were collected to measure Panc02-specific T cell responses by IFN-gamma ELISA. To measure the effect of IL PV-10 on the growth of an untreated, bystander tumor, mice received Panc02 cells in bilateral flanks. The resulting right tumor was injected IL with PV-10 or PBS. Tumor sizes were measured for both the right (treated) and left (untreated/bystander) tumors. To determine the efficacy of combination therapy with IL PV-10 and systemic Gem, mice bearing a single or bilateral Panc02 tumors were treated with PV-10 alone or in combination with Gem. Mice received 60 mg/kg Gem intraperitoneally (IP) twice per week.

    Results
    C57BL/6 mice bearing Panc02 tumors treated with IL PV-10 had significantly smaller tumors than mice treated with PBS (p < 0.001). A significant increase in the IFN-gamma production in response to Panc02 was measured in the splenocytes of mice treated with PV-10 as compared to mice treated with PBS (p < 0.05). Mice with bilateral tumors had a significant regression of tumors injected IL with PV- 10 and there was a reduction in the untreated (bystander) flank Panc02 tumor (p < 0.01). Gem therapy in combination with IL PV-10 injection led to enhanced tumor regression (p < 0.05) compared to IL PV-10 or Gem alone in both a single tumor model and a bilateral tumor model.

    Conclusions
    Regression of untreated pancreatic tumors by IL injection of PV-10 in concomitant tumor supports the induction of a systemic anti-tumor response. Addition of Gem chemotherapy enhances the effects of IL PV-10 therapy. Given that patients with metastatic pancreatic cancer have a dismal prognosis, combination therapy of IL PV-10 combined with Gem may benefit patients with metastatic pancreatic cancer.

    Updated (11/8/16).1: My underlined emphasis above. Note PV-10 use in the above murine model work as a monotherapy, and in combination with systemic chemotherapy.

    Updated (11/8/16).2: H/t @bradpalm1:

    Click to enlarge. Tweet image source
    "Gemcitabine reduces MDSCs, tregs and TGFβ-1 while restoring the teff/treg ratio in patients with pancreatic cancer," Eriksson et al., Journal of Translational Medicine 2016 14:282
    "Conclusions 
    Gemcitabine regulates the immune system in patients with pancreatic cancer including MDSCs, Tregs and molecules such as TGFβ-1 but does not hamper the ability of effector lymphocytes to expand to stimuli. Hence, it may be of high interest to use gemcitabine as a conditioning strategy together with immunotherapy."
    Updated (11/8/16).3: Unlike some, I do not read too much into Moffitt's abstract with respect to the additivity or synergism of PV-10 and gemcitabine (systemic chemotherapy) based on the cancer center's murine model work (i.e., p values of PV-10 alone, and in combination with chemo). And, I'd like to see the poster if Provectus facilitates its release (e.g., the company did not facilitate the release of Moffitt's AACR 2016 poster, which I believe may lead to a peer-reviewed publication).

    I believe the point of this mousie work, which of course is beyond cell line (in vitro) work but behind clinical studies, is to demonstrate in principle that (a) intralesional (IL) PV-10 could be used to treat pancreatic cancer (i.e., tumor type, leading to a suitable cancer indication) via (i) ablation/destruction of an injected tumor and (ii) the subsequent triggering of the immune response to reduce or destroy an untreated one, and (b) IL PV-10 plus chemo sees enhanced untreated tumor reduction or destruction.

    These principles of (x) ablation/destruction by injection and (y) immunologic signalling (immune system harnessing) already have been shown preclinically by Moffitt for PV-10 as a monotherapy in melanoma (also clinically) and breast cancer (AACR 2013), and in combination with checkpoint inhibition for melanoma (SITC 2014).

    So, this continues Rose Bengal, PV-10 and Provectus' theme of (A) agnosticism (ablation, immunologic signalling), (B) synergism (in that one therapy enhances another; "induce and boost"), (C) orthogonality (although this would be better shown in clinical work to emphasize no greater toxicity, if not less to far less), and...

    (D) PV-10 is an immunotherapy. See January 19, 2016 blog post PV-10 is an immunotherapy.

    October 19, 2016

    Turning [more anti-PD-1] non-responders into responders

    Image source
    Updated below: 10/19/16.

    What is PV-10's clinical value proposition to Merck & Co. (pembrolizumab, Keytruda®) and Bristol-Myers (nivolumab, Opdivo®), among other Big Pharma in the oncology space? In no particular order, is it, among other things:
    • As a primer, front-end, turner-on-of-the-engine, stepper-on-the-gas pedal, [insert your favorite over-, weakly- or wrongly-used analogy or metaphor],
    • Synergism, where from an efficacy perspective 1 + 1 >> 2,
    • Agnosticism to tumor type/cancer indication,
    • Safety profile, and/or
    • Turning cold tumors hot, and hot tumors hotter?
    Industry discussion appears to recognize immune checkpoint inhibitors work — when/where they do work — in a portion of cancer patients. Is the summary clinical value proposition of PV-10 in combination with Keytruda/Opdivo to make the latter (i.e., these anti-PD-1 drugs) work better when and where they work? Or is PV-10's proposition, the more powerful one, to show it can make Keytruda/Opdivo work better where they do not work?

    PV-10's clinical value proposition to Merck & Co. (pembrolizumab, Keytruda®) and Bristol-Myers (nivolumab, Opdivo®) is that it (PV-10) can turn more anti-PD-1 non-responders into responders than any other partner drug or investigational compound.

    For this blog post, consider, among other things, two combinations with pembrolizumab (for advanced melanoma):
    • Intralesional* agent electroporation with plasmid interleukin-12 (epIL-12) (ImmunoPulse, OncoSec), the combination of a medical device and an investigational agent, and
    • Intratumoral* agent toll-like receptor 9 (TLR9) agonist SD-101 (Dynavax), an investigational agent too.
    * Intralesional = intratumoral

    OncoSec. OncoSec announced in November 2014 it would combine ImmunoPulse and pembrolizumab, UC San Francisco and OncoSec Medical Collaborate to Evaluate Investigational Combination of ImmunoPulse and Anti-PD-1 Treatment. Data from this investigator-initiated study were presented at AACR 2016 (April), "Positive Melanoma Clinical Data at American Association for Cancer Research (AACR) Annual Meeting 2016," where patients initially were treated with ImmunoPulse and, then, some went to receive systemic anti-PD-1/PD-L1 therapy. Notably, however, OncoSec announced this month data from the same study would be presented at SITC 2016 (November), "Acceptance of Late Breaking Abstract at Upcoming Society for Immunotherapy of Cancer (SITC) Annual Meeting 2016," where the focus would be on [clinical data from] patients with a low likelihood of response to an anti-PD-1 alone (i.e., anti-PD-1 failures).

    Dynavax. Dynavax and Merck & Co. announced a collaboration in June 2015, Investigating the Combination of Immuno-Oncology Therapies. Initial clinical data of the combination of SD-101 and pembrolizumab in patients with metastatic melanoma was presented at ESMO 2016, "Phase 1b/2, Open-Label, Multicenter, Dose-Escalation and Expansion Trial of Intratumoral SD-101 in Combination With Pembrolizumab in Patients with Metastatic Melanoma." Preclinical work on SD-101 was presented at AACR 2016 by Dynavax observed, "These data provide a strong rationale for the clinical assessment of SD-101 in combination with agents blocking the PD-1/PD-L1 pathway in patients unresponsive to PD-1 blockade alone." Dynavax and Merck jointly observed on their ESMO 2016 poster, "Preclinical studies suggest that the immunostimulatory effects of SD-101 might also boost the activity of PD-1 checkpoint inhibitor therapy. In mouse models, SD-101 converted anti-PD-1 non-responders into responders by increasing the quantity and quality of tumor-specific T cells." {my underlined emphasis}

    In order for Provectus CTO Dr. Eric Wachter, PhD to put Provectus in a position to garner a collaboration with a Big Pharma and its immune checkpoint inhibitor, he has to provide a compelling demonstration of the features of PV-10 in combination with an anti-PD-1 drug like pembrolizumab (e.g., clinical trial PV-10 in Combination With Pembrolizumab for Treatment of Metastatic Melanoma). The features of this demonstration would include (a) preliminary safety and efficacy results, (b) immune biomarkers to facilitate appropriate patient selection if and when the combination is approved, and, presumably, (c) the ability of PV-10 to better turn anti-PD-1 non-responders into responders.

    Contesting anti-PD-1 non-responders into responders should be a big deal for Merck and Bristol-Myers because such contestation is all about eating more of the rest of the pie, much more so than fighting over the same sliver of it.

    Updated (10/19/16): OncoSec. ref. "OncoSec (ONCS) Q4 2016 Earnings Call Transcript," Seeking Alpha

    I referenced epIL-12 (and OncoSec) above because of the useful information regarding anti-PD-1 failures or non-responders. The oncology playing field continues to evolve, and combination therapy approaches clearly are evolving as well across multiple dimensions, like (i) determining which patients when and how [immune biomarkers], and (ii) expanding the addressable market from responders to non-responders.

    Among other aspects of an analysis of epIL-12 (and OncoSec), which historically has been mentioned together with Amgen's T-Vec and Provectus' PV-10, like at ASCO 2014 (see "Expert Point of View: Axel Hauschild, MD," The ASCO Post, Caroline Helwick, July 25, 2014), (a) there does not appear to be an initial pathway to approval yet (if at all) for epIL-12 as a monotherapy and (b) the investigator-initiated study was neither designed nor powered to transition to a pivotal trial as a combination therapy. OncoSec hopes to secure agreement with (acquiescence by) the FDA on a pivotal/registration trial design by the end of the year. Initial pathways to approval, like what Provectus has with PV-10 as a monotherapy for locally advanced cutaneous melanoma, as with valuable beachfront property, is valuable drug treatment "real estate." Nevertheless, it is a good strategy for OncoSec to focus on PD-1 failures; using emerging biomarker data to select "likely" PD-1 failures, however, is likely to prove somewhat more challenging. It will be interesting to see how this plays out.

    Dynavax. This is a true treatment combination and company collaboration (compared to the OncoSec treatment combination, for which the clinical trial protocol is here). The results are interesting, if not very preliminary (e.g., efficacy from 5 patients, measurement [for purposes of the ESMO 2016 abstract] was made after only 12 weeks). One would have hoped they could have provided a few more details (e.g, the number of injections of SD-101 [presumably 11 in total], more details on patient stage [particularly Stage IV, like M1a, M1b and/or M1c], what the grade 4 SAE was, etc.).

    A 25% serious adverse event (SAE) rate seems a bit high, and this is kind of an odd way to report safety data; usually this is reported as CTCAE Grade 3 or higher events since this includes both severe AEs and the subset of those that qualify as SAEs. Robert et al. reported 10.1-13.3% rate of Grade 3 or higher AEs for pembrolizumab alone (NEJM 2015;372:26).

    Notably, investigators/clinical sites on the poster included Agarwala/St. Luke's. The trial itself also is recruiting at Huntsman Cancer Institute (Andtbacka).

    Since this is a collaboration with Merck, it would appear the Big Pharma is not requiring rigorous safety testing before the project moves to Phase 2 (a Merck staffer is a co-author on the ESMO 2016 poster). The poster's Methods section notes the trial is a dose-escalation and dose expansion study. It shows data from dose-escalation (i.e., 2 mg, 4 mg, 8 mg), but does appear to refer to the dose expansion portion, which normally would be additional patients at the highest tolerated dose. The N = 6 at 8 mg is dose expansion but, again, if Merck wants to green light this work to a Phase 2 trial, [as a Big Pharma] they probably are not going to get significant push-back from the FDA or institutional review boards (IRBs). If a small biotechnology company has a major player backing it, it is possible to do things that are not plausible for outsiders (i.e., the golden rule). Finally, this study might give Amgen pause, since SD-101 appears to function similarly to T-Vec, may produce a more robust effect than T-Vec and, most importantly, is not a live virus.

    October 4, 2016

    Immunity

    Edited (by me) image above; original image source
    Let us take as given, finally in and by 2016, that PV-10 (chemical small [but heavy] molecule and halogenated xanthene Rose Bengal) is an immunotherapy

    That is, the investigational compound is potentially capable of inducing the human body's immune system to mount a possibly worthy defense against solid tumor cancer after first being injected into lesions and tumors of said cancer.

    That PV-10 has been independently shown to be that immunotherapy, at arms length from Provectus separately by both Moffitt Cancer Center (Moffitt) and the University of Illinois at Chicago (UIC) — reproducibility, the hallmark of Western Science— should make the claims about and data on PV-10 that much more veracious. See footnotes 1-5 below.

    But let's now examine the notion, and growing preclinical and clinical evidence, that PV-10 treatment — singularly or in combination — potentially may lead to something greater and more profound than just the inducement or generation of an immune response....immunity.

    AACR 2016 (April), Moffitt: T cell mediated immunity after combination therapy with intralesional PV-10 and co-inhibitory blockade in a melanoma model

    2016 (May) peer-reviewed publication, Moffitt: Intralesional rose bengal in melanoma elicits tumor immunity via activation of dendritic cells by the release of high mobility group box 1

    SITC 2016 (November), Moffitt: Intralesional injection with Rose Bengal and systemic chemotherapy induces anti-tumor immunity in a murine model of pancreatic cancer



    Footnotes of non-Provectus biomedical research for "PV-10 is an immunotherapy:"
    1. SSO 2012, Moffitt: Intralesional Injection of Melanoma with Rose Bengal Induces Regression of Untreated Synchronous Melanoma In a Murine Model,
    2. 2013 peer-reviewed publication, Moffitt: Intralesional Injection of Rose Bengal Induces a Systemic Tumor-Specific Immune Response in Murine Models of Melanoma and Breast Cancer,
    3. SSO 2015, UIC: Intralesional Injection of Rose Bengal Induces an Anti-tumor Immune Response and Potent Tumor Regressions in a Murine Model of Colon Cancer,
    4. 2015 peer-reviewed publication, UIC: The Potential of Intralesional Rose Bengal to Stimulate T-Cell Mediated Anti-Tumor Responses, and
    5. ASO 2016, UIC: PV-10 Induces Potent Immunogenic Apoptosis in Colon Cancer Cells,



    April 2016: Grant McArthur Discusses the Memory of Our Immune System

    September 26, 2016

    SITC 2016: Intralesional injection with Rose Bengal and systemic chemotherapy induces anti-tumor immunity in a murine model of pancreatic cancer

    Updated below: 9/26/16 {twice}, 9/28/16 and 9/30/16.

    Click to enlarge
    Updated (9/26/16): According to the Pancreatic Cancer Action Network, there are three chemotherapy drugs approved by the United States Food and Drug Administration (FDA) for the treatment of pancreatic cancer: albumin-bound paclitaxel (ABRAXANE®), gemcitabine (Gemzar®) and fluorouracil (5-FU).
    "Gemcitabine (Gemzar®) was approved in 1996 for the treatment of unresectable pancreatic cancer. Studies have also shown that there is a benefit to using gemcitabine after surgery for pancreatic cancer. Prior to gemcitabine, fluorouracil (5-FU) was used as the standard treatment for unresectable pancreatic cancer. Both of these drugs are still used today. 
    Most recently, in September 2013, albumin-bound paclitaxel (ABRAXANE®) was approved to be used in combination with gemcitabine (Gemzar®) as first-line treatment for metastatic pancreatic adenocarcinoma, the most common type of pancreatic cancer. 
    In addition to the three FDA-approved drugs, FOLFIRINOX, a combination of three chemotherapy drugs (5-FU/leucovorin, irinotecan, and oxaliplatin) is commonly used in the treatment of metastatic pancreatic adenocarcinoma. In 2010, a Phase III clinical trial showed positive results for patients treated with FOLFIRINOX. Due to the results of this study, FOLFIRINOX is also considered a standard treatment option for patients with metastatic pancreatic cancer. However, patients treated with FOLFIRINOX may experience more severe side effects than those treated with gemcitabine alone, so this combination is usually given to patients who are healthy enough to tolerate the potential side effects."
    Abraxane is made by Celgene. Gemzar is made by Eli Lilly. Provectus previously showed the combination of 5-FU and PV-10 for hepatocellular carcinoma in murine model work (SITC 2012).

    Updated (9/26/16): I believe the systemic chemotherapy used in Moffitt's work is gemcitabine (Gemzar®), which by now is produced by generics manufacturers.

    Some recent information on the competitive landscape for pancreatic cancer:
    • "Eli Lilly's chemotherapy drug Gemzar (gemcitabine) is widely considered the standard of care for pancreatic cancer. Generic gemcitabine is available from numerous companies" {January 2014 source},
    • "In the past, companies have combined various targeted treatments with gemcitabine in an attempt to increase their survival benefit. These efforts include Bristol-Myers Squibb/Eli Lilly's Erbitux, Roche's Avastin, Pfizer's Inlyta, and Amgen/Bayer's Nexavar, among others. Unfortunately, none of these drugs has shown a significant survival benefit when combined with gemcitabine" {above source},
      • "Frontline therapies for patients with metastatic pancreatic cancer have advanced in the past 5 years, with the FDA approval of nab-paclitaxel (Abraxane) plus gemcitabine (Gemzar). These advancements branch off the established treatment paradigm of gemcitabine monotherapy, which showed a significant extension in overall survival (OS) compared with 5-FU alone in a phase III study."
    • "Pancreatic cancer is a particularly tough cancer to treat and a number of other companies have failed in their efforts to develop an effective treatment. In February, Incyte halted trials of its drug Jakafi in solid tumors, after a Phase 3 study in pancreatic cancer failed to show efficacy. And this past May saw pancreatic cancer immunotherapies from NewLink Genetics and Aduro Biotech fall short of goal in Phase 3 and Phase 2b trials, respectively" {September 2016 source}, and
    • Momenta Pharmaceuticals has decided to end development of necuparanib, an experimental drug for advanced pancreatic cancer and the biotech's lead clinical candidate, according to a regulatory filing submitted Thursday. Enrollment in a Phase 2 trial testing necuparanib in combination with Celgene's Abraxane was halted earlier this month after an independent data safety monitoring board concluded treatment didn't demonstrate a sufficient level of efficacy {above source}.
    Updated (9/28/16): In 2011 co-founder and former Chairman and CEO Dr. Craig Dees, PhD presented Provectus' murine model work examining PV-10's "immunologic potential in treating melanoma and other cancer indications including liver, pancreatic and colorectal cancer." See several pertinent slides below.
    Click to enlarge
    Click to enlarge
    Click to enlarge
    Updated (9/30/16): H/t @bradpalm1: Vitamin D + immunotherapy + chemotherapy..."Physicians and Physicists Join Forces to Fight Pancreatic Cancer," The Wall Street Journal, September 25th, Ron Winslow
    "The team is planning a clinical trial soon in which patients who are candidates for pancreatic-cancer surgery first will be treated with synthetic vitamin D, chemotherapy and Bristol-Myers Squibb Co.’s cancer immunotherapy Opdivo. Opdivo is one of the new so-called checkpoint inhibitors that are transforming treatment of cancers such as melanoma and lung cancer. The drugs work by releasing brakes on immune-system T cells, enabling them to pursue tumor cells." 
    Bristol-Myers also is combining Opdivo with several other companies and drugs to treat pancreatic cancer, such as Celgene (Abraxane/Paclitaxel protein-bound) and Aduro Biotech (CRS-207 and GVAX)*. Opdivo combination trials for pancreatic cancer on CT.gov include at least eight studies.

    * CRS-207 and GVAX failed as a regimen for pancreatic cancer.

    September 14, 2016

    Life & Death, and the Biggest Checkbook

    Without being in the situation (because, um, close to doesn't cut it), a Provectus shareholder cannot fully evaluate the possible quality/quantity of potential introductory, follow-up and/or advanced meetings Provectus could/may have had, and/or could/may be having, with prospective Big Pharma partners about combination or cocktail therapy for end-stage cancer patients. The question a shareholder asks of course is to what extent is Big Pharma interested in and/or kicking the tires of chemical small molecule, ablative immunotherapy PV-10 for potential combination with their respective systemic immunomodulatory or targeted cancer agents, with the goal of such discussions being to hopefully and eventually arrive at a clinical combination and business collaboration.

    Some shareholders may have read about or heard rumors of recent discussions with Big Pharma that on the surface seem to denote interest. I cannot speak to that; all I can observe are the single or multiple, domestic or international, visitors and visits to or brush bys this blog via corporate-named routers from Amgen, Astellas Pharma, Bristol-Myers, F. Hoffmann-La Roche, Genentech (Roche), Gilead Sciences, Johnson & Johnson, MedImmune (AstraZeneca), Merck and Co., Novartis, Onxeo, and Pfizer. Visits could suggest blog reading. Brush bys may be the result of Internet search engine keyword searches. There could be other or more visits from Big Pharma and/or biotech folks via visitors' Internet service providers but I have no way of telling other than the occasional, reasoned guess about a location, such as Kenilworth, New Jersey (possibly for Merck and Co.) or Abingdon, Oxfordshire, UK (possibly for PsiOxus Therapeutics).

    What is it that we really know about Provectus' progress, if any, towards a so-called co-development transaction that company management has insinuated, implied, suggested or said is imminent, around the corner, near-term, close, etc. for several years now (the volume of which seems to have grown louder this quarter)?

    As early as the summer of 2014, I recall hearing of entreaties regarding combination studies to Merck and Co. by a strategic advisory board member and an oncology key opinion leader on behalf of Provectus. There also were rumors of several possible related interactions over time, such as a visit by a Merck executive to a medical conference to hear a Moffitt Cancer Center speaker talk about PV-10, and preclinical oncology work by the Big Pharma using off-the-shelf Rose Bengal.

    As 2015 turned to fall, with apparently no partner(s) in sight, let alone in hand, to pay for a checkpoint inhibitor-based clinical combination study involving PV-10, Provectus issued press release "Announces Initiation of Phase 1b/2 Clinical Trial to Study PV-10 in Combination with Immune Check Point Inhibitor Pembrolizumab" in September to commence its own clinical combination work on advanced (metastatic; Stage IV) melanoma. The trial protocol for this study obviously was developed well before the announcement. There was no need for a supply agreement with Merck (i.e., no official collaboration) because pembro already was approved for the solid tumor cancer indication under investigation, and its trial cost thus would have been reimbursed. Provectus was going to be the sole sponsor of the clinical work.

    The press release laid out management's then preclinical, clinical and intellectual property management plan to present and protect PV-10 as the ideal (perfect?) primer or front-end for Big Pharma's so-called checkpoint inhibitor backbone for treating end-stage cancer patients:
    At the time Provectus management seemed to have a heightened sense of expectation Pfizer would make a big deal of the patent award, which did not materialize save for a tortured inclusion of Pfizer's name in a press release. This perspective of "let's not undermine Pfizer" emanated at the time from both COO and Interim CEO Peter Culpepper and CTO Dr. Eric Wachter, PhD, who preferred I not blog about the patent award date (that I had learned about several weeks earlier via the US PTO's Patent Application Information Retrieval website) until after the patent award was awarded (patent awards are made on Tuesdays by the PTO). See Pfizer's Just Not That Into You (August 21, 2015) and Intellectual Property (August 18, 2015) on the blog's Archived V News page,
    • The initiation of the company's own melanoma combination therapy study program in September was Step #2.
    By sponsoring/conducting the trial by itself, Provectus owns all study data (per standard contract language applicable to clinical investigators, trial sites, CROs, etc. involved in the study). It will be customary to report top-line data in public venues like biomedical conferences and journals (e.g., potentially a 1Q17 conference); however, the full data set remains under the company's control, which is typical of any sponsored clinical trial. The detailed clinical data regulators ultimately would review, however, remains solely the property of Provectus, unless the company enters into a deal that affords access or rights to a third party, and
    • Step #3 was the completion/publication in May 2016 of Moffitt Cancer Center's mechanism of action work in melanoma on PV-10.
    Entitled "Intralesional rose bengal in melanoma elicits tumor immunity via activation of dendritic cells by the release of high mobility group box 1," Eric noted its importance and context on Provectus' August 10th 2Q16 business update call, saying that after "...years of work conducted by Moffitt Cancer Center both in animals and man...it is now clearly accepted that tumor ablation with PV-10 can lead to stimulation of a useful anti-tumor immune response." In other words, PV-10 is an immunotherapy. See January 19, 2016 blog post PV-10 is an immunotherapy and May 12, 2016 blog post Moffitt: IL RB in melanoma elicits tumor immunity via activation of DCs by the release of HMGB1.
    But by this time, the spring of 2016, there still was no co-development transaction (let alone multiple ones the company thought, and still thinks, could materialize). Possible explanations, aside from simply lack of interest on the part of Big Pharma, might have included to a greater or lesser degree:
    • The September 30, 2015 approval of the combination of nivolumab and ipilimumab for patients with advanced melanoma (BRAF V600 wild-type), which may have temporarily stymied interest in combination therapies for this indication,
    • The need to at least wait for the October 2015 approval of fellow intralesional (IL) or oncolytic therapy talimogene laherparepvec (T-Vec, Imlygic®),
    • Pfizer saying, at the January 2016 JP Morgan Healthcare conference, that is would bypass melanoma for its checkpoint inhibitor, anti-PD-L1 agent avelumab, to pursue "less competitive" cancer indications. If Pfizer were uninterested in melanoma for avelumab as a monotherapy, it would seem to suggest the Big Pharma also would be uninterested in combination therapy just for melanoma too, and
    • The growing realization checkpoint inhibitors no longer were/are the panacea the pharmaceutical industry and its constituent sycophants first thought they were. Clear, unequivocal limitations include:
      • Applicability to 20-30% of cancer patient population,
      • Ineffectiveness in less immunogenic cancer indications (i.e., cold or colder tumors),
      • Reaching toxicity and adverse event limits of checkpoint inhibitors (and targeted therapies) as both monotherapies and combination therapies (but since they are better than chemotherapies, management of such has grown acceptable), and
      • Realizing another set of tools, so-called primers or front-ends (i.e., co-stimulatory, agonists, "turn on the engine," "press the gas pedal," etc.), were necessary to combine with "back-end" co-inhibitory blockade.
    If I had to summarize the above "explanations" in hopes of elucidating why a co-development transaction has not yet materialized for Provectus, I now might solely focus on the need for Provectus to:
    • Move beyond melanoma to show combinatorial, primer or front-end relevance in other solid tumor cancer indications, and
    • Establish predictive tools or measures of treatment success in a nascent, overhyped era of precision medicine, like immune biomarkers derived from both peripheral blood and tumor tissue, also in multiple solid tumor cancer indications.
    Nevertheless, one could reasonably argue Provectus and other biomedical researchers have made preclinical, clinical and intellectual property management progress toward presenting and protecting PV-10 as the perfect primer or most complementary front-end to most if not every major cancer treatment category: chemotherapy, radiation therapy, targeted therapy, and immunotherapy.
    • Preclinical data related to combination therapy
    • Clinical data related to combination therapy
      • PV-10 + radiotherapy
    • Intellectual property related to combination therapy
    It is possible at least three Big Pharma could have some level of interest in pairing PV-10 with their immunotherapy agents: Pfizer (anti-PD-L1 with Merck KGaA), Merck & Co. (anti-PD-1), and Bristol-Myers Squibb (anti-PD-1).

    Pfizer Inc. Over at least the last five years Pfizer has been consistently wrong or late to the oncology/immuno-oncology (I-O) game:
    • November 2014: Pfizer buys (out-licenses) an anti-PD-L1 agent, later named avelumab, from Merck KGaA for an $850 million upfront payment and other considerations. Merck gets anti-PD-1 drug pembrolizumab approved for metastatic melanoma as Keytruda® in September 2014, while Bristol-Myers gets its anti-PD-1 relative nivolumab approved for the same indication as Opdivo® in December of the same year,
    • September 2015: Bristol-Myers gets its combination of anti-CTLA-4 Yervoy® and anti-PD-1 Opdivo® approved for metastatic melanoma. Following Bristol-Myers' non-small cell lung cancer trial failure of Opdivo as a monotherapy, Wall Street analysts peg AstraZeneca's combination of anti-CTLA-4 tremelimumab (previously in-licensed from Pfizer) and anti-PD-L1 durvalumab as capable of potentially taking market share away eventually from Bristol-Myers' approved combination therapy. See Pfizer sale/outlicense above,
    Click to enlarge
    • January 2016: Having admitted the company was late to immuno-oncology, Pfizer says during the JPMorgan Healthcare Conference that it will be "a leading player in the second wave of combinations." As of this writing, Pfizer has 8 open oncology combination studies, compared to 180 for Merck and 132 for Bristol-Myers, and
    • August 2016: Pfizer buys Medivation for $14 billion, more than 50% higher than Sanofi's initial April bid in April.
    But, Pfizer is the one of these three Big Pharmas with the biggest checkbook, and into August 2016 still was working with Provectus to advance their joint oncology combination therapy patent portfolio (one patent and two patent applications). See More Intellectual Property Management (September 11, 2016) and Is Pfizer paying more [IP] attention to Provectus? (September 2, 2016) on the blog's Current News page.

    Pfizer seemed to have entered Provectus' picture around late-2010 to early-2011 when Provectus and it appeared to have begun writing and then initially filing (in March 2011) the combination therapy patent application that eventually would be jointly awarded to them by the U.S. Patent and Trademark Office (US PTO) in August 2015 as "Combination of local and systemic immunomodulative therapies for enhanced treatment of cancer" noted above.

    Initial interest in and the rationale for combining an immunomodulatory agent (anti-CTLA-4 compound tremelimumab) with PV-10 began with Provectus strategic advisory board member and Pfizer executive Dr. Craig Eagle, MD, who apparently conceived of the idea apart from Provectus' co-founders. Eagle reasoned an antigen cascade or "storm" ("antigenization") would be kicked off or initiated by the substantial size and scope of tumor destruction initially caused by PV-10 ablation (injection). The subsequent PV-10-based antigenization would induce an immune response -- otherwise known as priming -- that then could be boosted by the immunomodulatory (or targeted) agent. CTO Dr. Eric Wachter, PhD noted as much in a recent US PTO filing when he wrote "President" and co-founder Dr. Tim Scott, PhD did not anticipate tumor ablation would have "a downstream immune system priming systemic effect" and that this systemic priming effect could "synergize with known systemic agents."

    Ironically, from today's perspective and pharmaceutical industry focus on oncology combinations and cocktails, it would seem Eagle thought enough of PV-10 to suggest its combination with anti-CTLA-4 agent and ipilimumab relative tremelimumab, but not enough to expansively protect Pfizer's interest in the ensuing combination therapy patent. According to Provectus, Pfizer does not benefit from its co-ownership of the combination therapy patent portfolio unless it acquires the company.

    But, as I wrote before, Pfizer has the biggest checkbook -- if it wishes to open it -- in the event it again is late to the I-O game by not initially entering into a co-development relationship with Provectus before another Big Pharma does.

    Merck & Co. Anti-PD-1 drug pembrolizumab (trade name: Keytruda®), first approved in for patients with advanced melanoma in September 2014, breathed new life into Merck's oncology franchise almost 18 months after current head of R&D Dr. Roger Perlmutter, MD, PhD re-joined this company from Amgen in March 2013.

    In a Barron's August 31st article entitled "Merck: Lung Cancer Lead Depends On “How Smart It Plays Its Hand,”" Bernstein analyst Tim Anderson said:
    "One of the frequent criticisms with MRK’s I/O program has been that, relative to competitors like BMY/AZN and Roche, its “combination” strategy is less clear, with many believing MRK could be left in the cold over the long run because of this. This is too simplistic of a view, in our opinion. 
    MRK has already placed its bets on “chemo combo” through the earlier initiation of trials like Keynote-189 and Keynote-407. In the area of CTLA4 combinations, we believe the chances are high that MRK will soon initiate a phase 3 development program (exact scope unclear) if only to hedge its bets in the event that trials like Checkmate-227 and MYSTIC/NEPTUNE are positive. 
    While the onus is on BMY and AZN to fully validate CTLA4 combinations, all MRK has to do is imitate given its sudden lead in the monotherapy 1L lung cancer market that came about through the very different fates of Keynote-024 and Checkmate-026. 
    In other potential combination areas with anti-PDx therapies and “3rd generation” agents (e.g. OX40, GITR, IDO, and more) the playing field is more level across the different drug companies. Like its competitors, MRK already has various assets in development – either owned in entirety or accessed through partnership. Progress with almost all of these later generation drugs, across all companies, has seemed to be on the slower side; activity in a single-agent setting, for example, has often seemed underwhelming, in contrast to the single agent activity seen with the anti-PDx’s and anti-CTLa4′s. 
    Lastly, even if “combination therapy” comes to fruition and the data is compelling (whatever the regimen), there will likely be the attendant trade-offs of incremental toxicity and higher cost. Therefore, it seems likely that some segment of the 1L lung cancer market will continue to exist for anti-PDx monotherapy, where MRK has a first-mover advantage. 
    On balance, we continue to think investors under-appreciate the potential durability (and value) of MRK’s coming lead in 1L lung cancer. Part of this depends on how smart MRK plays its hand from here."
    I recounted above what I believe is Merck's historical curiosity or interest (is there a better descriptor?) in PV-10. Below is a quickly constructed, cursory overview of combination collaborations (e.g., announced, supply agreements only, etc.) between Merck and other companies for pembrolizumab in advanced melanoma.
    Click to enlarge.
    A search of CT.gov for "pembrolizumab combination melanoma intratumoral" yields six open studies; there are three other trials for different indications (a total of 9). "Pembrolizumab combination intralesional" yields two trials (PV-10, T-Vec).

    What kind of agent is Merck searching for to pair with pembrolizumab? What defines an ideal drug partner for pembro? One way to answer these questions is to consider former Moffitt and current NYU Langone Medical Center key opinion leader's comments to me that (paraphrasing) the utility of a primer is simply its ability to synergize with the immune agent in question in terms of clinical effect when given prior to the second agent. Moffitt data showing the strength of the systemic responses PV-10 can stimulate (i.e., efficacy of PV-10 plus a checkpoint inhibitor >> efficacy of the checkpoint inhibitor alone) should make this/his point). See August 17, 2014 Immune Surveillance.

    Another way is to recount Moffitt's Dr. Vernon Sondak, MD's (and Provectus consultant's) characterization of PV-10; see June 29, 2014 blog post Properties of PV-10:
    • Simple to store, handle and use and reuse,
    • Modest local toxicity and minimal to no systemic toxicity,
    • Rapid and complete induction of necrosis/antigen release in injected lesions,
    • Excellent healing of the injected site after tumor necrosis, and
    • Reliable and reproducible induction of regional and systemic immune effects capable of destroying occult tumor cells, "bystander lesions" and distant metastatic lesions regardless of prior treatments.
    If Merck settles on what it believes to be a more ideal partner for pembrolizumab, it further breathes life into its cancer immunotherapy franchise. As such, I am intrigued by Merck's most recent collaboration with Biothera, which pairs pembro with a pathogen-associated molecular pattern-based (PAMP-based) compound. PAMPs are "molecules associated with groups of pathogens, that are recognized by cells of the innate immune system." It would seem Merck is creeping closer and closer to understanding how to turn (induce) cold or cold tumors hotter (via Biothera's PAMP) so as to boost the immune response subsequently generated by pembro.

    Well, PV-10 could be called a DAMP-based compound. "Damage-associated molecular pattern molecules (DAMPs) also known as danger-associated molecular pattern molecules, are host molecules that can initiate and perpetuate a noninfectious inflammatory response." And, DAMPS are recognized by both the innate and adaptive immune systems. See Immunological “ignition switch” (August 26, 2016) on the blog's Current News page.

    Click to enlarge. Image source
    Bristol-Myers Squibb. And then there's Bristol-Myers, which has the most to lose of these three Big Pharmas with its interchangeable, anti-PD-1 drug nivolumab (Opdivo®), also approved initially for melanoma shortly after Merck's version. Bristol executives faced a "near-death experience" on August 5th that continues by virtue of a declining share price that currently shows no sign of abating. See August 30, 2016
    The Day Big Pharma's Earth Stood Still, which was visited by several times by Bristol-Myers Internet Protocol addresses (among other visits to this blog).

    If nivolumab and pembrolizumab are interchangeable, and Bristol-Myers has no meaningfully different marketing department than Merck's, Bristol-Myers' "death" potential remains viable so long as it does not find an ideal combination partner for Opdivo® and Merck does. Should cancer combinations (or cocktails) rule the day for late-stage cancer patients for the time being, the ideal primer or most complementary front-end for a combination therapy would seem to be the greater or greatest differentiation. See February 18, 2015 The Early Obsolescence of Checkpoint Inhibitors. Own it, live. Lose it, die.