Sorry for the long introduction, I'll jump straight into my first guest author blog post from Phil Kobierowski (@philkobi on twitter). I don't know Phil personally, but have exchanged several tweets with him over the last several months. It did not take long for me to realize that he is both an intelligent and very respectful guy, and I am pleased to share with you his "bear views" on Celsion. Note, his disclosure is listed at the bottom of the post.
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Celsion and the Risks of Clinical Trials
By: Phil Kobierowski, @philkobi (celsion.blogspot.com guest author)
As we near the results of the pivotal, long-awaited, Phase III
"HEAT" clinical trial for Celsion Corp’s ThermoDox, optimistic
investors might want to take a step back and consider why they are holding shares
of Celsion (CLSN) and evaluate the potential risks associated with clinical
trials.
The HEAT trial is Celsion’s double-blinded, placebo
controlled Phase III trial for the treatment of primary liver cancer, or hepatocellular
carcinoma (HCC). Here are five reasons
that would dampen my enthusiasm regarding the upcoming HEAT trial results that
are expected to be announced around December 2012:
- The first item worth noting is that I should have been
writing this almost two years ago. What
that means is that Celsion management has been notorious in missing their
forecasted milestones.
The HEAT trial seemed to start well. On a press release issued September 24, 2008 "Celsion reports that site initiation and patient enrollment are tracking well against its most recent projections." This led to their forecast 19 months later in May 13, 2010 that predicted the trial ending a year and a half before Celsion’s current December 2012 forecast: "Celsion expects the study could be completed by the middle of 2011, and pending positive data, a New Drug Application would be submitted to the FDA before the end of 2011". September 21, 2009, is another example of HEAT trial delays, this time regarding patient enrollment completion: "We expect to complete enrollment in the spring of 2010." Then, in an August 24, 2010 press release, we see Celsion’s expected enrollment completion pushed-back over half a year: "With nearly 70% of patients enrolled in the trial, Celsion is targeting to complete patient enrollment by year end 2010." When did full enrollment finally happen? July 2011 for the initial target enrollment of 600, and May 2012 year for the full target of 700.
Granted, if the HEAT results are solid, these delays are a moot point. Delays in clinical trial completion are not rare and certainly not proof of problems with the trial. Nonetheless, if Celsion management has significantly missed their forecasting of how the HEAT trial would progress, what other parts of the trial might they be missing or will be a surprise to investors? For example, is the control arm of the trial significantly exceeding Celsion’s expectations when compared to the ThermoDox arm? - The noticeably low market cap of Celsion has long been a
mystery, for me at least. Despite the share price tripling from June to
September of this year (followed by the recent pullback), the current $145
market cap is paltry for a company with a promising, late-stage product that is
a potential first-line standard of care treatment for a major cancer.
Is this a hidden opportunity, or is there a hidden, unpublicized reason for this? Has the aforementioned timeline delay in the HEAT trial’s completion caused a lack of credibility with, or lack of interest from, investors? After so many years of developing ThermoDox, medical conference and Wall St road show presentations, etc, it's hard to think that the low market cap is due to the market being really unaware of Celsion. So what is the reason? The voice in my head (one of them at least) brings to mind to adage: “if you don't know who is being set-up as the dupe at the poker game, then it's you”. I’m just sayin’… - There is a shortage of evidence supporting the efficacy of
ThermoDox. Celsion's Phase I clinical trial
for ThermoDox in liver cancer showed very promising results, no doubt, with a
very compelling dose-response correlation. But with only 7 of the 20 patients enrolled in
the entire trial (plus 4 who were censored from results) who were diagnosed
with HCC (the HEAT trial indication), and with the lack of a Phase II trial
because Celsion moved from their Phase I right to the Phase III HEAT, well, … you
get the point.
Some could argue that Celsion’s recently released DIGNITY Phase I trial results (using ThermoDox for the treatment of recurrent chest wall breast cancer – another of several indications being considered for ThermoDox) looked encouraging, and therefore, would be reconfirming of ThermoDox’s’s potential. But, there is really no way to compare the results of the small, 11 patient group in the DIGNITY trial - who were all previously treated with harsh chemotherapy and/or radiation treatments - to those in the 700 patient HEAT trial where ThermoDox is a front-line, induction therapy. Further, the trials are conducted on completely different indications and are evaluated by very different endpoints. It is just 2 totally different situations. - The HEAT trial is
only 80% powered for its endpoint of a 33% improvement in progression free
survival (PFS) over the control arm. This
means that even if ThermoDox could produce such a 33% PFS improvement if used as
a global standard of care, and the HEAT clinical trial procedures, protocols,
etc, have no glitches; there is still a 20% chance that the HEAT trial is not
powered sufficiently to demonstrate that its primary endpoint is met.
Granted, if ThermoDox’s actually efficacy far exceeds this 33% PFS improvement (as it very well may) then the powering of the trial becomes less of an issue. But, there is still an unavoidable element of random luck involved and the potential of a steep drop in share price if things don’t work out.
Further, the HEAT trial is being conducted in 79 different, globally located, clinical sites, of which only nine are in the United States. The administration of radio frequency ablation (RFA) is a key component in both the ThermoDox arm and the control arm in all the study sites of the HEAT trial. (Both arms use RFA to burn cancer tumors, the heat of which triggers the injected ThermoDox – which is technically a temperature sensitive liposome that encapsulates doxorubicin – a common chemotherapeutic agent, to release its chemotherapeutic payload at the tumor site.) The effectiveness of RFA may significantly be determined by the skill and practice of the individual interventional radiologist performing the RFA in the HEAT trial, who are located in, and have been trained, from all parts of the globe. Considering this, and that ThermoDox may have little effect on any cancer cells located away from the ablated tumor(s), it becomes evident that there are many elements that will affect the results of the HEAT trial, perhaps negatively, that have nothing to do with ThermoDox. - Will the unique
requirements for administering ThermoDox restrict its adoption? ThermoDox is not a cure, but only a treatment
that hopes to post-pone the recurrence of cancer by several months longer than current
treatments (such as RFA alone). As
mentioned above, ThermoDox is administered in conjunction with a heat source;
RFA in the case of the HEAT trail.
ThermoDox is injected intravenously (IV), then 30 minutes after the IV,
the RFA procedure must be initiated. Any
period outside this 30 minute window reduces the optimal pharmacokinetics, and
thus the effectiveness, of ThermoDox.
One under-publicized concern is the extra logistical effort required coordinate this: two different procedures, conducted at two different locations by two different staffs at a hospital or oncology center. All within a very tight timeframe. The poster presentation of the aforementioned DIGNITY trial acknowledges this challenge with ThermoDox: "CHALLENGES - Infusion of cytotoxic agent in chemotherapy suite followed by transfer to radiologic oncology to administer hyperthermia." Such a challenge is seemingly manageable in a clinical trial setting where there are just a few patients and where it is possible to get simultaneous coordination from all needed medical staffs. But how will this translate as a standard of care, where care centers are large, understaffed, and unexpected delays are the norm?
For the sake of Celsion, its investors, and most importantly for the benefit of the tens of thousands of patients that could benefit from such a potentially beneficial treatment as ThermoDox, we should all hope for positive data results from the HEAT trial. And I acknowledge there are many reasons (that I have not discussed here) to believe that it may. But that should not preclude each investor from objectively assessing the risks inherent to any investment.
Disclosure: I am a long-term Celsion shareholder with no plans to initiate a net short position.
Disclosure: I am a long-term Celsion shareholder with no plans to initiate a net short position.