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Showing posts with label RXi Pharmaceuticals. Show all posts
Showing posts with label RXi Pharmaceuticals. Show all posts

Wednesday, November 22, 2017

RNAi Therapeutics Stocks (Part 2)

Having covered the most developed RNAi companies (Alnylam, Arrowhead, Dicerna) yesterday, this blog entry will discuss RNAi plays that are somewhat less established, but nevertheless could represent interesting investment opportunities.

Silence Therapeutics (SLN.L)
This London-listed company is roughly 2 years behind Arrowhead Pharmaceuticals and Dicerna.  Similar to those, Silence has set its sights on exploiting targets in liver hepatocytes using GalNAc conjugate technology.  Its first program targeting TMPRSS6 for iron overload disorders should enter the clinic in the first half of 2019.

The strength of Silence is partly its RNAi trigger IP position which, if the claims stand, should read on Alnylam’s 3-4 drug candidates that could come on the market over the next 2-3 years.  In my opinion, it would take a generous interpretation of what constitutes a ‘pattern’ for LNP-enabled Patisiran to fall under Silence IP, but it is much less of a stretch for the more stabilized GalNAc-enabled Givosiran, Fitusiran, and Inclisiran molecules in late-stage development.
Part of the potential upside could  therefore come from a settlement of the IP litigation that Silence has filed against Alnylam as it could hamper the commercialization of Alnylam's RNAi drug, especially as it ramps up for the launch of Patisiran. 

The reason why such revenues would be meaningful to the company is that Silence is run extremely well in financial terms such that these funds would neatly feed into Silence's operations as it is about to expand clinically all the while minimizing shareholder dilution. 
This, however, could also be viewed as a necessity since it is much more difficult for a London-based company to raise the kind of biotech ‘risk capital’ that allows companies like Alnylam in the US to really press down the gas pedal to pursue a grand vision without killing shareholders.   

Silence Therapeutics is an investment for those that value the pursuit shareholder return instead of mere market cap growth (=management bragging rights).  While I support this strategy, I am still largely on the sidelines as the company needs to address the anemic trading volume which makes it very costly to trade in and out.

RXi Pharmaceuticals (RXII)
Who doesn’t dream of striking it rich overnight?  If so, RXII is the type of stock that in the right biotech environment could be your daily biotech double in the not-so-distant future.

After all, which other biotech with a market cap of ~$15M can boast about 3 clinical data read-outs before year-end and one additional in early 2018?

1) Q4 2017: phase II results dermal scarring (RXI-109)

2) Q4 2017: phase II results warts (samcyprone, non-RNAi)

3) Q4 2017: UV-induced hyperpigmentation results, consumer testing (RXI-231)

4) Q1 2018: phase I/II results retinal scarring (RXI-109)  

It is possible that the first 3 data read-outs could show that the agents are active and well tolerated, but where there will be a discussion about the commercial adoption of these agents in the real world.  Therefore, the real fireworks may occur following the results from the retinal scarring phase I/II trial in early 2018.  Here, the self-delivering RNAi trigger technology is tested for the first time in the eye where for reasons of technical feasibility (more equal biodistribution throughout eye than in the skin) and clinical application I see the most potential for this technology.
Downside risk comes from management that is pitifully ignorant about the workings of the financial markets and shareholder value creation.  If RXi fails to ignite investor interest in the wake of any of these 4 shots on goal, we could well see a continuation of the financial death spiral that has seen RXII lose 98-99% of its value in the last 3-4 years!!!

I own approximately 3% of the outstanding shares of RXII and will try to add on any weakness ahead of data release.

Arcturus Therapeutics (ARCT)
In sharp contrast to RXi, I view management of Arcturus as far more savvy when it comes to the financial markets and building a biotech company of decent size.

Arcturus, which has recently gone public via a reverse merger, has its roots in RNAi technology, largely by copying liposomal delivery technology from Tekmira (now Arbutus) and then licensing related RNAi IP from Marina Biotech.  In light of the Patisiran APOLLO results, you could view the platform as fundamentally de-risked.
In fact, its lead program was an RNAi program to address TTR amyloidosis.   Since then, however, Arcturus has largely re-tooled itself as an mRNA Therapeutics company using LNP delivery technology.  Although its pipeline is not as prolific as that of much-better known Moderna, it appears impressive for a company with a market cap of still less than $100M just as its partnering activities.

Therefore, Arcturus is a bet on a management that can take average science to build a significant biotech as it talks the language of Wall Street and Pharma deal makers.  It was one of my early biotech investment mistakes to undervalue big-mouthed management relative to science. The best science can always be acquired once you have lowered your cost of capital by growing market cap.
I have a starter long position in ARCT as I wait for it to be discovered by larger hedge fund manager.

The final instalment of this series will cover oligonucleotide therapeutics companies Ionis Pharmaceuticals, Wave Life Sciences, Regulus Therapeutics, and Sarepta.

Wednesday, October 18, 2017

Can Transient RNAi Augment Cell Therapy-based Immune Oncology?

Unlike all the major RNAi pure plays (Alnylam, Arrowhead, Dicerna, and Silence Therapeutics), RXi Pharmaceuticals is not pursuing GalNAc-based gene knockdown in the liver.  Instead, it applies its self-delivering RNAi (sdRNAi) triggers to local and, more recently, ex vivo gene suppression.

Its ex vivo efforts involve the addition of the silencing triggers to immune cells in the absence of extraneous transfection reagents with the goal of enhancing the performance of cell therapy-based immune oncology.  Immune oncology, of course, is a hot area in drug development.  Notable clinical successes mechanistically aim at immunologically unmasking tumor cells (à checkpoint inhibitors) or sending T-cell killers after them (à CAR-T).

Transient RNAi non-obvious application to cell therapy

When sdRNAi licensee MirImmune, now part of RXi came forward with the idea of applying transient RNAi strategies to cell therapy, I was very skeptical.  Cell therapies after all suggest that long-lived pharmacodynamics are desired, whereas RNAi gene silencing in dividing cells is known to be limited in duration, maybe a week or so.  Wouldn’t therefore gene therapy and in particular genome editing for gene ablation be much more useful?  Or what about that half-forgotten DNA-directed RNAi?  

Certainly, for gene silencing effects that ideally should last throughout the active life of the adopted cells in the patient, transient RNAi is not attractive given all the alternative technologies out there such as genome editing and of monoclonal antibodies.

On closer inspection, however, transient RNAi may be able to uniquely achieve a number of goals that could uniquely enhance adoptive cell therapy for cancer and potentially other applications, too.  One of them is to simply increase the number of cells with the desired phenotype.  After all, the patient-derived cells used for adoptive cell transfer are a precious resource and manufacturing issues could result in cell numbers too low to be useful.  Accordingly, self-delivering RNAi triggers may increase the number of useful cells either by expanding them, e.g. by targeting cell cycle-related genes, or by more effectively directing them to the desired phenotype (e.g. tumor-attacking vs protecting/tolerogenic cells).   

Importantly, as sdRNAi does not require electroporation or transfection reagents, there is less risk that the procedure itself reduces cell numbers or has undesirable effects on the cell phenotype. 

Out of the test tube and into patients, transient RNAi could also be useful in helping in the early tasks of the adopted cells.  One such early step is infiltrating the tumor which is thought to have a major impact on immune oncology treatment success.  While tumor infiltration can be expected to be largely guided by proteins interacting on the cell surface and would seem a suitable application of monoclonal antibodies, monoclonal antibodies often have difficulties getting into tumors.  

It is also conceivable that an early performance provided by transient RNAi may have a lasting effect on eventual therapeutic outcome, e.g. by hitting the cancer hard initially so that the risk of immunologic escape by mutation is minimized.  This is similar to how early reductions in pathogens predict the treatment success of most infectious diseases such as HCV.

Finally, RNAi may be applied to multiple genes at once.  This is more difficult to do with systemically administered monoclonal antibodies, and unlike monoclonal antibodies, RNAi can also inhibit proteins not accessible to monoclonal antibodies; multi-targeting is also less effective with genome editing.

Looking ahead

Transient RNAi for adoptive (immune) cell therapy is in its early stages.  Given some of its unique characteristics, it could be a useful addition to the gene toolbox next to genome editing, DNA-directed RNAi, or simple gene addition.  While RXi is planning to plod along with preclinical proof-of-concept studies, as a non-immune oncology person and given the poor capitalization of the company, I particularly look towards clinical collaborations and corporate partnerships to judge just how compelling a tool transient RNAi really is here.


RXi as an investment or trade

RXi Pharmaceuticals is a small biotech company with a tiny market cap of ~$13M and I would be remiss not to mention that I currently own somewhat more than 2% of the outstanding shares (ticker: RXII).  This is a relatively small gamble on my part, but certainly enough to keep me interested and engaged. 

Right now, it is probably not much more than a gamble given that RXi’s management has displayed an extraordinary degree of naivete about the capital markets.  Accordingly, their continued operations currently largely rely on an ATM-type arrangement with Lincoln Park Capital Fund which appears to only have accelerated putting down the stock, and possibly eventually the company down a death spiral. 


Near-term, RXII is therefore a bet that management will finally stop this nonsense and instead rely on the upcoming multiple (!) clinical trial outcomes catalysts by year-end from at least 3 (dermal scarring, cutaneous warts, consumer skin products) of its non-immune oncology portfolio to create some excitement about the stock.  Results from a retinal scarring trial are expected in early 2018.  Considering the tiny market cap of ~$13M, the sheer number of upcoming data read-outs alone could result in mouth-watering stock returns if the stock gets discovered.  Such a run-up would of course also provide financing opportunities to feed its immune oncology ambitions, so please management: don't put a lid on it by activating the ATM.

Thursday, May 28, 2015

RXi Pharmaceuticals Could Be Much More Than Skin Wound Healing

RXi Pharmaceuticals today commenced a secondary offering setting it on course to raise ~$10M, enough to finance the company for another year while expanding its pipeline and technology.  It could thus mark a new chapter in the life of this company which had shoe-boxed itself into a single-product (RXI-109 for dermal wound healing) company following a toxic 2012 financing that gave Tang Capital Partners de facto control over the company (pro tip: when you see the likes of Tang or Deerfield getting involved, it usually is not to the benefit of common stock holders). 

The news this morning that the preferred stock overhang (àTang Capital Partners) had finally been cleared, then paved the way towards the financing (amount and pricing to be determined).  

With RXI-109 winding its way through phase II studies, it became clear that RXi had to open itself up to new opportunities enabled by its promising self-delivering RNAi platform.  The financing will initially allow RXi to develop RXI-109 also for ocular (retinal and corneal) scarring-related indications such as wet AMD and cataract surgery.  First eye-related clinical trials with self-delivering RNAi triggers are expected to commence later this year.

The eye is an interesting application of sd-RNAi technology not only for the lucrative eye disease market (both genetic and age-related of considerable unmet medical need), but also because they seem to be able to penetrate throughout the eye (see image) whereas in the skin, distribution currently is limited to areas close to the injection site barring new delivery breakthroughs (patches, creams and the like).  In addition to cholesterol, it may also be interesting to test other ligands such as Vitamin A and E for enhanced uptake into certain ocular cell types.

Lots of unexplored potential

Beyond the skin and eye, self-delivering RNAi strategies hold considerable promise for other tissue targets, both by direct/local and systemic delivery.  In terms of local delivery, I would be highly interested in the biodistribution of intrathecally administered sd-RNAi triggers in non-human primates.  This is because of their long phosphorothioated single-strand overhang and thus similarity to phosphorothioate antisense oligonucleotides which are starting to show amazing results in the clinic for CNS applications (watch out for update on the infant ISIS-SMNRx study by Isis Pharmaceuticals).

In terms of systemic delivery, sd-RNAi chemistry and structure may synergize well with conjugate-RNAi approaches, both in their simple (--> Alnylam GalNAc-type) and more refined form (--> Arrowhead DPC-type).  Even without further modification, RXi-type self-delivering RNAi has shown surprising knockdown efficacy in models of pre-eclampsia as shown by respected UMass scientists Melissa Moore and Anastasia Khvorova (formerly of RXi Pharmaceuticals).  

If RXi can get the backing from serious biotech investors and eventually a new management fit to lead a modern biotechnology company, the current $16M market valuation (for RXI-109 in the clinic for dermal scarring and soon in the eye; self-delivering platform potential; stake in MirImmune) of the company could make it an irresistible investment opportunity.  If management, however, continues to dig in their heels and refuses to listen to outside advice chances are that the financial death spiral will continue. 
   
Suspicious shorting into financing

It used to be common biotech practice that investors-in-the-know were allowed to short into financing resting assured that the offering will allow them to cover at a lower share price.  It is therefore remarkable that in the days and weeks before the financing, the short interest has sky-rocketed from virtually none to around 10% of the float and possibly much more by now due to the delays in reporting short interest.

Tuesday, December 23, 2014

RXi Pharmaceuticals Reality Check

Last week on December 17, RXi Pharmaceuticals announced (3-month) results from a phase II study of the company’s lead candidate RXI-109, an RNAi Therapeutic for the treatment/prevention of dermal scars.  

In this lower abdominal scar revision study 1301, one side in a given patient was treated with drug on days 1, 8, and 15 following surgery (immediate group) or on days 14, 21, and 28 (delayed group), while the other side was given placebo.  An assessor blinded to which side was injected with RXI-109 or placebo was then asked to tell drug from placebo. 

According to the release, the drug-treated side was (correctly) identified 54% of the time in the delayed treatment cohort versus 24% of the time in the immediate treatment cohort.

In the absence of further information on the identification procedure and scoring used (e.g. it is likely 'there is no difference' was a possible answer which would somewhat undersell the results), the following interpretation seems logical: in the delayed treatment cohort skin wounds treated with RXI-109 looked no different than those treated with placebo.  Moreover, when treatment was started soon after scar revision surgery, RXI-109 possibly did harm.

It certainly would have helped if RXi provided the VAS score as it did in the one-month update in September.

To me, this result looks like one of the worse types of biotech trial failures.  If you like to talk about 'misleading', then RXi should not look further than the title of their own press release on this failed study:

'RXi Pharmaceuticals Announces Sustained Effect of RXI-109 at Three Months Post Scar Revision Surgery and the Completion of Enrollment for its Phase 2a Trial RXI-109-1301'

Two days after the clinical trial news, the company then announced that it had licensed a non-RNAi dermal compound which is currently in phase II studies for cancer and other proliferative diseases of the skin.  A proprietary formulation of small molecule ‘immuno-modulator’ diphenylcyclopropenone (DPCP), aka Samcyprone, from an obscure company called Hapten Pharmaceuticals.


Now on to RXi’s financials...

At the end of Q3 2014, RXi had about $10M in net cash ($10.69M cash/cash equivalents minus $1M in liabilities), spending about $2.25M a quarter.  This means they presently have ~$8M in cash minus the undisclosed cash it spent on the Hapten deal.  If RXi continued with RXI-109 and RNAi and if it initiated the phase II clinical studies with Samcyprone, the cash burn would obviously increase.  Let’s say to $4M per quarter à $8M/($4M per quarter)= 2 quarters of cash left.

...and RXII the stock

Obviously realizing that the new asset is not not solving their  financial predicament, by contrast it is only worsening it, concurrent with the Hapten deal RXi entered into a new stock purchase agreement with Lincoln Park Capital ('ATM') according to which RXi Pharmaceuticals can sell LPC newly issued shares to raise capital.  The way these deals work is that LPC would get a discount on the shares and turn around and sell to the public market to lock in the profit.  This means that if RXi really counted on such revenues to keep their PCR machines running, any substantial rally in RXII is likely to be met with the selling of new shares.

Adding to the pressure is the fact that major shareholder Tang Capital, holding just shy of 50% of the fully diluted share count, has been steadily selling down its ownership in RXi.  Moreover, some of the Hapten deal (incl. milestones) was/will be paid in shares and it would be reasonable to suspect that the owners of Hapten are not in it for the potential of making money with speculating in RXII shares.  

If you consider a fully diluted market cap of $70-80M, the present situation with RXI-109 and the failure for years (also under Galena) to advance the self-delivering RNAi platform, the case can be made that there are better biotech stock investments out there.

Pick your poison

For the above reasons (including financial limitations), I tweeted last week that the move to license Samcyprone more or less amounted to RXi Pharmaceuticals getting out of the RNAi game.  In fact, the bitter irony is that RXi was born out of parent company Galena Pharmaceuticals making exactly the same move (marginalizing RNAi by acquiring a non-RNAi clinical asset).

So yesterday, the CEO of RXi Pharmaceuticals issued an Open Letter that, to sum it up, I was misleading the public with my conclusions about the strategic shifts happening at the company and was thereby scaring investors into selling their shares:

'We can only hope that investors and shareholders who read blogs, tweets and postings from third parties purporting to have an informed view on our business will also do an in depth evaluation of the background of those who write such "reports", their past contributions to the actual progress in the RNAi space, and their possible associations to competitors and other firms working in a similar space. Notwithstanding these ill-informed criticisms, we remain optimistic about the prospects of the Company and our core technology.'

By contrast, RXI-109 was on track, the company’s RNAi platform alive and kicking, and immune modulator (aka skin irritant) Samcyprone fully being aligned with RNAi gene silencing as it changes gene expression (I’m impressed).

At this point, a friendly piece of advice: RXi ought to label Samcyprone an 'immuno-oncology' drug which would almost sound as sexy as the VEGF compound RXi is now 'synthesizing'.

So I’m not sure what to hope for: a) that the CEO does not understand that continuing with two phase II compounds under present circumstances is akin to financial suicide, especially from a shareholder’s point-of-view; or b) that he understands it and scapegoats social media, including myself, for calling the bluff in an effort to win time.
   

I suspect it’s the latter and either way shareholders are unlikely to come out ahead.  After all, when he took the helm of RXi Pharmaceuticals at a time when it was fashionable to bash and ridicule RNAi, he made it clear that he was a ‘small molecule guy’ at heart. If I may ask you Geert, what exactly were your contributions to the actual progress of RNAi Therapeutics?

Tuesday, November 4, 2014

Ocular Applications Back in the Focus of Oligonucleotide Therapeutics

Following yesterday's disclosure that yet another one of GSK’s target picks for clinical development under their antisense options agreement with ISIS Pharmaceuticals is an ocular one, I thought it worth highlighting that ocular applications are regaining traction in oligonucleotide therapeutics in general.  This follows a temporary lull in the area due to setbacks with older generations of the technologies and funding issues for the industry.

Aptamers still in the lead

It may surprise you, but the eye is the one area in oligonucleotide therapeutics where aptamers, nucleic acids binding protein targets based on their shape not sequence (similar to antibodies), are most advanced.  Despite of the fact that the first approved aptamer, Macugen, is considered a great disappointment as it lost out to the monoclonal antibody competition in the VEGF market for wet AMD and DME, there are at least two new development candidates that are poised to become blockbusters in the same market: Fovista by Ophthotech targeting PDGF which has shown unprecedented activity in a phase II study in combination with anti-VEGF antibody Lucentis, and an earlier-stage, but potentially superior VEGF/PDGF bispecific aptamer approach by privately held SomaLogic.

It is now thought that the Macugen failure was due to it not targeting the relevant VEGF isoforms.  In other words, it was a failure of target selection/biological insight, not a failure of the technology.  Aptamers should work well for trapping extracellular proteins for ocular applications, because unlike their often rapid elimination following systemic administration, they can be maintained at elevated concentrations in the eye for sustained periods of time.  Their limitation, however, is in the number of targets available to them, similar to monoclonal antibodies.  Nevertheless, it should be kept in mind that with even just 2 or 3 commercial successes in a therapeutic area, a platform technology can be considered tremendously valuable there.

Gene-regulatory oligos catching up

Although ocular drug development has also been popular in both the antisense and especially RNAi fields, previous technology generations were inadequate to effect robust gene modulation, especially target gene knockdown.  This holds true for 1st (à Vitravene) and 2nd generation (cRaf inhibitor by iCo Therapeutics) antisense and the ‘naked’ RNAi trigger folly of the early days of RNAi Therapeutics (à Acuity Pharmaceuticals, Sylentis, Quark, and Sirna/Allergan to name just some of the worst offenders of sound science).

The reason why antisense and RNAi are both staging a comeback in ophthalmology is due to the use of higher affinity chemistries (e.g. cET by ISIS) and self-delivering RNAi triggers, both in the form of (partially) double-stranded (e.g. sd-rxRNAs by RXi Pharmaceuticals) and single-stranded RNAi triggers (à ISIS Pharmaceuticals).  The increased stability and lipophilicity combined with small molecular size should allow such an RNAi approach to efficiently penetrate the vitreous of the eye following needle injection and reach deep into the retina and other ocular structures.  Similarly, what used to be a mediocre 40% knockdown for ASOs could now be a genetically much more useful 70-80% knockdown with gen2.5 RNaseH.

It is too early to tell whether RNaseH gen2.5, ssRNAi, or sdrxRNAs will win out in the end.  At least in terms of timing, it will be as much a matter of investing in the technologies as it is about their potential.  In particular, I am disappointed by the failure of RXi Pharmaceuticals to recognize the need to further develop their sd-rxRNA chemistry.


So keep your eyes peeled as clinical results from the new wave of gene-modulating Oligo Therapeutics will start to emerge in 2016 and beyond.  It is possible that QPI-1007 by Quark Pharma for ocular neuroprotection for NAION may be earlier than that, although the chemical nature of this ‘2nd generation’ non-AtuRNAi trigger remains unclear to me and therefore might be, or might not be a 'self-delivering' RNAi trigger.  If not this one, the upcoming clinical development of CTGF-targeting RXI-109 for retinal scarring by RXi Pharmaceuticals should be an interesting one to follow.

Wednesday, September 10, 2014

RXi Provides Disappointing Clinical Update for Scarring Drug

At the Rodman & Renshaw investor conference today, the CEO of RXiPharmaceuticals dropped a little bombshell in the form of a disappointing clinical update on their lead clinical candidate, RXI-109 for the treatment or prevention of dermal scarring.  In that interim look for efficacy, RXI-109 and placebo were not really distinguishable in scar severity sending the stock down 30-40% in the middle of today’s trading session.

1301 study design

The 1301 study is the first of three phase IIa studies evaluating 109 in a number of different scar settings.  In this case, RXI-109 was administered following scar revision surgery on the lower abdomen.  Part of the same scar received either 3 injections of the self-delivering RNAi compound, another part placebo solution.  Half of the subjects (50% of the study/16 subjects have enrolled as of today), received 109 on days 1, 8, and 15 following surgery (cohort 1), the other half received injections on days 14, 21, and 28 following surgery, the latter apparently inspired by clinical design trends observed for competitor antisense drug from Pfizer/Excaliard.

I find that blindly adjusting your clinical design based on such competitive intelligence is a worrisome sign of lack of confidence.

1301 study results

The first interim look for efficacy took place at 1 month post-surgery.  Results were based on the blinded visual assessment of scar severity on a scale from 1 (good fine-line scar) to 10 (worst scar imaginable). 

Unfortunately, the close to 50% knockdown of target CTGF observed in a similar 3-dose phase I study, did not translate to an obvious improvement in scar severity: for the immediate treatment group, the VAS score was 2.0 for both the 109 and the placebo side of the scar; for the delayed treatment group, the VAS score was slightly better in the 109 side (2.0) than on the placebo side (2.5) even reaching statistical significance.

Before you get excited and buy into the biological rationalizations by the CEO for why it makes sense that delayed, but not immediate would exhibit such a benefit, note that a VAS difference of 0.5 on a scale from 1 to 10 would appear to be clinically meaningless despite the statistical significance.  Moreover, looking at the VAS scores across the board, it seems that the placebo side in the delayed treatment cohort is a statistical outlier as it should not have performed any different than the placebo cohort in the immediate treatment group.    

On the other hand, given that the scars have not had time to fully develop and the VAS scores were still so low, it is possible that real differences will emerge at later time-points such as month 3 when the next interim look will take place and it may thus be premature to declare the study or drug for that matter a failure.


RXi needs a plan B and investors patience

In light of the disappointing trial update, it may not be a coincidence that Geert Cauwenbergh today took the opportunity to talk more about their other, preclinical pipeline candidates in the dermatology and ophthalmology space in much more detail than had been the case.   

I am less excited about the prospect of RXi expanding their dermatology footprint given the relatively modest gene knockdowns observed, limited tissue penetration from the site of injeciton, and the cosmeceutical nature of their current line-up (acne, depigmentation etc).  By contrast, I am much more excited about  the prospect and value of self-delivering RNAi triggers in the ophthalmology space given the great unmet medical needs there and the highly encouraging tissue penetration/biodistribution data for self-delivering RNAi in that organ.

There will be more to talk about that in the future.  As stock market investors, however, one has got to wonder whether management is aware of that value and knows how to best exploit it (pro tip: VEGF is a no-no for RNAi in the eye).  Even more concerning is the fact that the majority shareholder (Tang Capital) still holds close to half of the company and is in the process of unloading it thereby putting constant pressure on the stock. And with only $10M in the bank, you know what the trip to the Rodman & Renshaw conference was all about.


So no more than a small starter position for me despite the steep sell-off today.

Tuesday, January 28, 2014

Antisense Comparison Provides Hope for RXi’s Dermal Scarring Drug Candidate

In early December, RXi reported phase I data from new cohorts that were added to the multi-dose study of RXI-109 in dermal scarring.  Accordingly, by increasing the dose to 10mg self-delivering RNAi trigger from previously 7.5mg per injection site, the company was now able to achieve a 50% target CTGF gene knockdown (5 and 7.5mgs: 43%). 

Based on the meager 30-40% knockdowns and apparent efficacy that were observed in comparable clinical studies targeting the same CTGF with a phosphorotioated antisense compound at 5mg per cm scarline­, the prospects of RXI-109 would suddenly appear to be much brighter.  Of course, the ISIS compound was spun out into Excaliard which was then acquired by Pfizer in late 2011 for the apparently promising data observed with the dermal scarring candidate EXC001.  EXC001 is now in late-stage clinical development.

Of course, there are a number of caveats with this reasoning.  For one, although the study protocols appear very similar, it is possible that the tissue biopsies taken to obtain the CTGF knockdown measures were of dissimilar sizes.  Given that CTGF knockdown can be expected to wane quickly away from the injection site, such differences could have a material effect on the apparent knockdown efficacy. 

On the darker side, when you consider a nice visual therapeutic effect (see picture) in light of a 30-40% knockdown, you start to wonder whether the actual effect on scarring was less due to blunting of CTGF expression and more due to some non-specific immune-related effect of the phosphorothioate backbone in the antisense compound.  The RXI-109 compound may not ‘benefit’ from such an effect.


Nevertheless, the 10mg dose results are a step forward and form a useful basis for the phase II studies that RXi Pharmaceuticals will be rolling out this year in lower abdominal scar revision (already initiated), keloid scar revision, and scar revision following cosmetic breast surgery.  

Unfortunately, prospects would have been even brighter had the company employed a more potent RNAi trigger design.  And when the CEO, in 2014, still shows a slide with Kreutzer-Limmer controlling dsRNA lengths of 15bp and over (to justify the use of dsRNA < 15bp), I would suggest they update their presentation slides.  Similarly, it would be honest to not talk about a market cap of $50M, but to present their more meaningful capital structure, including preferreds and the like.

Tuesday, December 24, 2013

The Retina within Sight of RNAi Therapeutics

 From the highly prevalent diseases such as the age-related macular degenerations (dry and wet) to the rarer, but more numerous diseases such as the retinitis pigmentosa, the eye is the subject of a significant and growing unmet medical need.  From a genetic point of view, the application of RNAi Therapeutics to these diseases is very attractive.  However- yes, you guessed it- delivery challenges have made it difficult to exploit its potential.  In 2013, I have come across at least two pieces of evidence, one in synthetic and one related to DNA-directed RNAi, which make me believe that the time for ocular RNAi Therapeutics is nigh.

A bit of history

Following an early rush into ocular diseases that saw 3 wet AMD RNAi candidates, one each by Opko Health, Quark Pharmaceuticals (partnered with Pfizer), and Sirna Therapeutics/Merck (partnered with Allergan), speed into phase II and III studies, considerable doubts about their scientific foundations killed off the enthusiasm.  

Firstly, it was thought that the preclinical validations of the wet AMD candidates rested on TLR3-activation artifacts.  While I have not seen this claim more widely supported and chemical modifications and short double-strandedness should readily get around this issue, the more vexing question to me has been how were these either unmodified or simply 2’-O-methyl modified, unformulated RNAi triggers supposed to enter their target cells?

Moreover, for ddRNAi where Genable Technologies is readying an AAV-based candidate for retinitis pigmentosa to commence clinical trials, vector distribution following needle administration represents serious safety and efficacy issues.  Because the AAV and lentiviral gene therapy workhorses do not diffuse on their own from intravitreal injection sites to the back of the eye, ocular gene therapy has largely involved subretinal injections which a) is a relatively dangerous procedure that can seriously harm retinal architecture and integrity, and b) limits vector diffusion and therefore therapeutic activity to a small area surrounding the subretinal administration site.

Smartly evolved AAV can penetrate from the vitreous into the retina

In order to develop viral vectors capable of overcoming the physical barriers between the vitreous and retina, Dalkara and colleaguespublished earlier this year a study on the selection of AAV2 variants capable of doing just that. 

The selection process of this now popular method of directing AAV to various tissues and cell types starts out with large libraries of more or less randomly mutated AAV variants.  In each selection round, the viral DNA is extracted from the target cells and re-amplified for the next round of selection such that the AAV variants that most efficiently transduce the target cells eventually become highly enriched.
 
The 7m8 AAV that they identified was thus capable of broadly transducing retinal cells following intravitreal administration in mice, from the inner ganglion cells to the outer retinal pigment epithelial cells.  In non-human primates, 7m8 also greatly enhanced retinal penetration from the vitreous compared to old gold standard AAV serotypes.  However, retinal cells were not transduced as broadly as in mice suggesting that either additional candidates from mouse evolution experiments need to be characterized in non-human primates or that the selection itself should be performed in non-human primates.

I view such progress exceptionally promising for retinal degenerative diseases in which rescue of only a fraction of cells should be therapeutic (e.g. by getting rid of a mutant mRNA that leads to the death of the cell expressing it), but potentially also for the more challenging disease settings where RNAi action would probably have to occur in the majority of cells in order to be therapeutic.
 
Along these lines, after deciding on the best AAV variant, an important task will be to determine the more precise percentage of cells of each cell type that can be transduced to then match them up with potential indications.

Sticky self-delivering RNAi triggers penetrate deeply into the retina

In the field of synthetic RNAi Therapeutics, a peer-reviewed paper came out by RXi Pharmaceuticals (Byrne et al.) which confirmed earlier claims that self-delivering RNAi triggers (sd-rxRNAs as they call their own versions) were able to fully penetrate the retinal cell layers in both the mouse and rabbit following intravitreal injections.  The rabbit is an important model because their eye volume, believe it or not, is close to ours (~1.5ml vs ~5.0ml).  Formal proof of RNAi-mediated gene silencing was then confirmed in the mouse.

The self-delivering RNAi triggers had guide strands of ~19 nucleotides and passenger strands of less than 15 nucleotides.  An extended phosphorothioate (PS) single-stranded tail on the guide and additional hydrophobic modifications such as sterol groups were supposed to enhance tissue penetration and functional cell uptake.  The 6-8nt PS tail obviously has been borrowed from standard antisense chemistry.  Therefore, a battery of tests was performed to exclude visual abnormalities resulting from these extensive modifications.  No notable tox findings were made.
Despite the similarities in chemistry, sd-rxRNAs appear to be superior to ISIS-type PS-ASOs (RNaseH mechanism).  This is because in the Byrne et al. study, ~3 microgram RNAi trigger was required for 50% gene knockdown, whereas 50 micrograms phosphorotioate antisense oligos were required for a 50% knockdown of MALAT as presented by ISIS at OTS 2013 in Naples (report still available).  To wit­, MALAT as a nuclear RNA can be expected to be far more susceptible to RNaseH ASOs than your average mRNA, so the potency difference could be even bigger.  Also, it would be interesting to determine the safety implications of administering 3 micrograms versus 50 micrograms or whatever the equivalent dosages in humans.

The potency difference would have been much bigger still if RXi were not so married to their less than 15bp double-strandedness, a misguided decision driven by old IP considerations (when the Kreutzer-Limmers were still a concern).  I therefore expect other RNAi companies with more active R&D to thank RXi for the validation and come up with more optimal RNAi reagents for ocular applications.
Ocular RNAi Therapeutics- keep an eye on it in 2014 and beyond.

Tuesday, December 3, 2013

Delivery Advance Illustrates Influence of Cosmetics Skin RNAi Therapeutics

The skin has always been a target organ of considerable interest to the RNAi Therapeutics industry due to its apparent accessibility for delivery purposes plus the fact that there are various unmet needs ranging from the severe genetic disease (e.g. epidermolysis bullosa, pachyonycia congenita) to cosmetic desires.  Interestingly, it is the latter that in many ways is driving skin RNAi Therapeutics these days.

Motorized microneedle array with unprecedented silencing efficacy
    
In an important advance in the rate-limiting area of delivery, Hickerson and colleagues from TransDerm and various other collaborators recently published 80% gene silencing efficacy in a mouse model for epidermal gene expression using a motorized microneedle array borrowed from the cosmetics industry (in particular the Triple-Mby BomtechElectronics of cosmetics hot-spot South Korea).  This compares to 50% and 33% gene silencing in the same model using simple (static) microneedle arrays and intradermal needle injection, respectively, before.  Accordingly, this represents a 2.5 to 3.5-fold increase in gene silencing efficacy when considering how much of the undesired target protein you are left with!

I have to admit that I did not double-check that indeed the same siRNA sequences and self-delivering RNAi trigger modifications were used in the various studies which could have affected results.  However, since these results have all been reported by TransDerm and the goal of TransDerm was to compare delivery efficacies of various technologies, I am willing to accept the comparability claim by the authors. ­

The trick with the motorized microneedle array appears to be that following penetration of the stratum corneum barrier motion (oscillation) allows for a larger volume of drug to be deposited in the epidermis than with a static needle array.  Moreover, the depth of administration can be adjusted for optimal epidermal delivery and to make it pain free as well, unlike the original high-pressure hypodermic needle attempts by TransDerm.   With this, it should be possible to deposit low single-digit milligram of RNAi triggers to an area the size of a tip of a thumb- which is quite a bit.

A possible limitation of such microneedle arrays is that the administration itself causes microinjuries to the skin.  Therefore, you want to make sure that you do not end up making things worse, especially in applications where wound healing and restoration are the goal.  Since the technology is apparently used in the beauty industry already, it is unlikely that its application will leave insightly scars and the likes.

I look forward to seeing a technology like motorized microneedle arrays in conjunction with self-delivering RNAi trigger formats being used in the clinic.  Initially, the technology is most amenable to applications where the focus is on locally defined areas such a skin parts prone to blistering.  However, taking advantage of imaging technologies and 3-D printing, I envision a future in which the technology would also be possible to treat large areas of the skin, if not the entire body surface.  As TransDerm illustrates, combining the capabilities of existing technologies from disparate areas often enables the biggest advances.

RXI-109 for dermal anti-scarring now available under the ‘Specials’ provision in the EU

Anybody that has gone to a dermatologist knows how blurred the lines between medical and cosmetic applications have become when it comes to the skin (cosmeceutical concept).  Taking advantage of the regulatory grey zone, it is skin applications that are leading the charge in the commercialization of RNAi gene silencing in WoMan.  Following a claimed treatment for skin blemishes marketed as Britena Whitening & Anti-blotch Cream by Biomics (partnered with Benitec on HepB), it is now RXi Pharmaceuticals that has signed a distribution agreement for its dermal anti-scarring drug candidate RXI-109 with Ethicor. 

The goal of this arrangement is to drive early sales based on an exception of European drug legislation that allows for the use of experimental drugs prior to proper marketing authorization.  All it apparently takes is a judgment call by the treating physician.  I can see the point of this ‘Specials’ provision for severe, orphan diseases as a form of compassionate use when there is intriguing early clinical evidence of efficacy and safety, but for an anti-scarring treatment, mmh...you can easily see how consumers willing to take risks in the quest for beauty will make their physician give them an injection of the stuff.


But then again, when you see how much unproven, potentially harmful potions and lotions are being sold on the cosmetics market, it is hard to argue why you should make an exception with RNAi as long as care is being taken that somewhat riskier (depending on chemistry) systemic exposures remain low and yours truly does not have to pay for it via increased insurance premiums.  I guess my biggest problem with all this is that the company distributing RXI-109 calls itself ‘Ethicor’ just as I get nervous when somebody starts a sentence with ‘to be honest’ and what follows is more often than not a lie.

Friday, July 12, 2013

RXi Reports 43% CTGF Knockdown in Multi-Dose Dermal Anti-Scarring Trial

Today, RXi Pharmaceuticals announced the results from its multi-dose phase I study of RXI-109, the company’s self-delivering RNAi compound for dermal anti-scarring.  Importantly, in the two highest of the three dose cohorts a credible 43% (average) gene knockdown was observed three days after the last (=third) intradermal injection of RXI-109.  It is the first time that a knockdown was reported for the so-called ‘self-delivering’ class of RNAi triggers.

The results followed those from a single-dose study lastmonth where dose-dependent gene knockdowns were claimed three months after the single injection (note the difference in the time points).  Turns out that this was a slightly misleading conclusion as in my book a numerical 15% target reduction does not constitute a clinically meaningful knockdown for the vast majority of target genes and indications, and I'm not even discussing the precision of gene expression measurements.

Whether a 43% knockdown of CTGF is clinically meaningful also remains to be seen as no data were presented on the actual impact of RXI-109 on scar formation.   Pfizer, following its acquisition of dermal scarring antisense company Excaliard, would probably know best what type of knockdown was required.
   
In a broader sense, the 43% number also raises the question of whether self-delivering RNAi triggers by RXi Pharmaceuticals will be a class of gene silencing agents that will struggle to achieve 50% gene silencing, instead of 70, 80, 90% and more that might be required for most indications.


Overall, mediocre results and it stands to reason that the future of RXi Pharmaceuticals will be in ocular indications and not in dermal anti-scarring.

Comment on Alnylam's $3B market cap

I, like many of you, have watched with wide open eyes Alnylam reaching a $3B market cap today. In less than two weeks, this company added over $1B in valuation based on highlighting in their press releases the best single datapoints from individual patients (e.g. 'over 80% knockdown' for ALN-TTRsc), instead of average knockdowns, area under the curves, and dosages.

While that does not entirely surprise me as a veteran of reading between 'topline data', a more intriguing question is what the company will do with such a low cost of capital.  Remember, the situation was similar about 5 years ago when Alnylam failed to either raise capital and/or acquire Tekmira to avoid the litigation.  I expect the company to act this time on its share price, a view supported by constant analysts upgrade on any news piece the company throws in front of them (--> fees for investment banking business).

Thursday, June 6, 2013

RXi Reports Dose-Related Knockdown Three Months Following Single Injection

RXi Pharmaceuticals today reported top-line results from the first of two phase I studies with RXi-109 in dermal scarring.  Intriguingly, the company claims to observe target gene knockdown three months following a single intradermal injection of their self-deliverable RNAi trigger (p=0.02) in a manner that was apparently dose-related. 

Such a drug-dependent and dose-related knockdown would exceed my expectations from this trial as stated in a recent preview here.  The reason why I merely expected to see a correlation between CTGF levels and phenotypic effect on dermal scarring being reported today is that I did not have high confidence that the tissue residence time of RXI109 would be prolonged enough to observe a bona fide RNAi knockdown. 

To wit, the tissue biopsy on which this data rests was obtained during a tummy tuck three months after the intradermal injection of the RNAi.  To assess whether there was an RNAi knockdown in such a single-dose study, I would have thought that an early time-point such as two weeks after injection would have been more appropriate, also because it is likely that some of the CTGF-producing cells might be proliferating in this setting (RNAi duration inversely correlated to proliferation status).

The notion that a correlation between CTGF levels and wound healing would be observed was based on CTGF reflecting tissue inflammation.  So regardless of whether there was an RNAi effect or not, you might expect to see such a correlation.  It is difficult, however, to explain a drug-dependent and dose-related target gene knockdown with this notion, except for by a rare coincidence.

These results then bode well for the multi-dose phase I studies from which results will be reported in time for the Investor and Analyst Symposium on July 12.  While safety was the primary focus of the first study (no adverse event on the early wound healing process confirmed), the effect of RXi-109 on wound healing will be the focus of the second study.  It should be added though that given the small size of the trials and the patient population which is not predisposed to scarring, spotting the difference will be tough.

Disclosure: long RXII.

Friday, May 31, 2013

Can RXi Pharmaceuticals Spot the Difference?

The imminent announcement of phase I results for RXI109 will be a clinical highlight of RNAi Therapeutics in 2013.  RXI109 is the self-delivering RNAi trigger against dermal scarring and is developed by RXi Pharmaceuticals.  Needless to say, as the company is committing 90% of its resources to this trial and indication, the results should cause major volatility in the stock.

While the dermal anti-scarring landscape is complex, RXI109 for the present indication can safely be categorized as a cosmeceutical.  According to RXi Pharmaceuticals, already $100M are spent each year in the US on non-FDA approved ointments against dermal scarring.  The interest in RXI109 is thus for its commercial potential and the clinical results are a milestone in the development of so-called ‘self-delivering RNAi triggers’.

Self-delivering RNAi triggers are a concept coined first by Dharmacon (although one could argue that was largely a branding achievement as it essentially involved known cholesterol conjugation), but is getting more widely adopted these days.  Beyond its local indications for which they self-delivering RNAi triggers were initially developed, I expect the concept to also be applied to certain systemic delivery strategies.  I could imagine that in an effort to render GalNAc-siRNAs more potent, self-delivering chemistries will be useful.

Phase I studies

RXi has conducted two phase I studies.  In both studies, volunteers got multiple surgical incisions symmetrically on both sides of the abdomen.  For each pair of incisions, one side either received RXI109 or placebo by intradermal injection.  In the first study, RXI109 was given just once before incision, from 1mg to 10mg per 2cm incision (similar range as in the Excaliard antisense trials).  In the second study, RXI109 was given three times within two weeks from 2.5mg to 7.5mg per 2 cm incision.

In addition to safety and tolerability, the important endpoints will be a visual assessment of scarring and then, based on a biopsy obtained from a tummy tuck at Day 84, important biomarker data in the form of CTGF levels (the target gene) and a histological evaluation of the scar tissue.

Although this is a blinded study, the company has discussed blinded results in extenso.  On the safety front, there seems to be little cause for concern, and adverse events are consistent with what you would expect from an incision.  Management appears to be very bullish on the therapeutic outcomes since in many cases left and right sides look different.  So if they are different, the side that looks better should have been given RXI109, right? 

Unfortunately, you have to look very hard to spot the differences.  In one example shown, the ‘average differences’ in scar tissue area were 31%.  Since they will put their best foot forward with this example, the largest effect size that we can expect is 31%.  And this assumes that in each case, it is the drug-treated side that outperforms the placebo-treated side. 

It is thus difficult for me to be optimistic that this trial allows for a therapeutic effect to be demonstrated.  For this, the natural wound healing variability would have to be really small (I admittedly don't know what this is).  On the other hand, it is with this symmetrical, intra-patient control design that such small differences might be teased out.  Regardless, I expect enough data to be collected from the studies that it will make for a nice headline and narrative about how RXI109 had improved wound healing and the correlation with CTGF (I bet there will be a correlation, whether due to knockdown or not).

So while I think that RXI109 is a decent RNAi Therapeutics (not the best possible one given the short dsRNA length), it will be important to conduct future studies in patient populations more prone to scarring to increase signal to noise.  This could be for example in the scar-revision setting or in Asian populations.

   
Trading the event


As I expect major volatility and have some confidence in the science behind RXI109, I have taken a long position ahead of the event.  It is not clear whether the results from the two studies will be presented separately or together.  I suspect the latter given that the CEO of RXi in February/March guided the results from the first study to be forthcoming in April.  Since it is almost June already, it is likely that the company expects the biggest bang from presenting the results together.  This should happen before July.  Once again, given that there is so much potential for data-mining, I expect positive headlines- justified or not.

Tuesday, April 30, 2013

RNAi Therapeutics Companies Cashed Up and Ready to Strike


With the $36M fund-raising last night, Arrowhead Research has become the 4th publicly traded RNAi Therapeutics company in short succession to cash up for a real shot at drug development success.  The other companies are Tekmira, RXi Pharmaceuticals, and as it was made official this morning, Silence Therapeutics.

The money will be spent on promising drug candidates in the cancer field (TKM-PLK1, Atu027), chronic HBV (ARC520), and scarless wound healing (RXI-109) without having to take dangerous short-cuts or partner the crown jewels prematurely.  Moreover, it will help to advance critical delivery technologies such as DPC, SNALP, and self-delivering RNAi triggers which should provide for non-dilutive partnering opportunities without having to entertain low-ball offers.   

It is notable (and not surprising) that unlike Marina Biotech and Benitec which so far have failed to similarly escape the financing maelstro, Tekmira, Arrowhead and Silence all sport healthy in-house R&D operations.  RXi does not have such operations- yet.  However, they were critical for bringing RXI109 into the clinic on which the company’s ~$80-90M market cap rests.   

The cash infusions should also give the companies, which among them own most of the leading platform technologies, the opportunity to make up for the 20-30 fold gap in valuation to the likes of ISIS Pharmaceuticals (2.3B market cap in antisense), Alnylam (1.5B market cap in RNAi), and Sarepta (1B market cap for a phase II orphan indication).  If monoclonal antibodies are any guide, this will not play out as the winner-takes-all the public markets have it right now.

Below is a quick rundown of the newly cashed-up crop of RNAi Therapeutics companies for those new to the field.

Disclosure: I am long Tekmira and Arrowhead Research. 
Disclaimer: Investments in RNAi Therapeutics carry more risks than you want to know and think about.  The following can only be a very brief teaser for you to start your own due diligence.


Arrowhead Research: In the pursuit of a cure for chronic HBV

Market cap: ~60-70M (of which ~$35M in cash)

Unless Arrowhead Research comes up with a compelling orphan drug application of its technology when it will disclose its second development program in H1 2014, investment success will hinge on the fate of ARC520.  ARC520 is Arrowhead's unique attempt at a functional cure for chronic HBV that will enter clinical development shortly.  I interpret last night’s fund raising in that the IND-enabling tox studies were positive.  The results of these will be critical in determining whether ARC520 can be dosed high enough to safely achieve the type of 90% HBsAg reductions that will be required for that lofty goal.

With cash of around $35M, Arrowhead can now retain full rights to that program at least after value-inflecting phase I proof-of-concept knockdowns have been achieved.  To extend the cash runway beyond the predicted ~2 years, Arrowhead owns the exciting Dynamic PolyConjugate delivery technology, particularly the subcutaneous version and potential new developments for cancer applications.  DPC offers an obvious non-dilutive funding opportunity.

Having slept over the announcement of the PIPE financing which doubles the share count near multi-year lows, I believe it still was a good one in a difficult situation.  Potential partners would have liked to exploit the financial weakness of Arrowhead and the fast-money crowd (think Dawson and Rodman) would have liked to reap risk-free gains from trading around a public offering.  Instead, Arrowhead seems to have found one or more significant investors that share the vision with management.  It is comforting that besides the sweet entry price, no special gifts in the form of warrants and otherwise seemed to have been handed out.  No wonder Arrowhead closed up 13% the day after the financing.

Upcoming catalysts:

  - Determination of maximally tolerated dose in volunteer study with ARC520;
-          - DPC partnering (always on the table);
-          - Modest ALN-TTRsc results would emphasize value of DPC (mid-2013) and may get Alnylam into  play;  
-          - DPC data on cancer (probably H1 2013);
-          - Nominating new development candidate (Q2 2014);
-          - ARC520 viral knockdown results in the Hong Kong trial (H1 2014).


Tekmira Pharmaceuticals: Quality Technology, Quality Financial Management

Market cap: ~$70M (of which ~$40M in cash)

If you are looking for relative stability in RNAi Therapeutics, Tekmira could be attractive.  It was its SNALP technology that enabled the current revival (with well over $300M capital inflows in the industry in the first 4 months of this year) and remains one of the two leading systemic delivery technologies with the value possibly shifting towards oncology indications.  Its leading development candidate, TKM-PLK1 for solid cancers, is about to enter phase II studies and has yielded promising dose-related evidenceof efficacy in phase I. 

The company’s aerosolized LNPs could be an unanticipated windfall for investors, although I have yet to see the all-important safety data.  Its Ebola biodefense program is not valued much by the market, but has been an important stabilizing factor for the company in terms of funding and represents an attractive commercial opportunity in its own right.  

Upcoming catalysts:

-          - TKM-PLK1 data from the expansion cohort (H2 2013);
-          - Design and initiation of phase II studies for TKM-PLK1 (H2 2013);
-          - Follow-up candidate and potentially data for TKM-EBOLA (H2 2013);
-          - Nomination of new development candidate;
-          - $5M milestones each if ALN-TTR02 by Alnylam enters phase III development and Ascletis   initiates a trial in China with ALN-VSP02 for primary liver cancer (both H2 2013/H1 2014);
-          - Partnering of SNALP delivery technology, also for non-RNAi, non-therapeutic applications (always on the table);
       - Monetization of Talon royalties (uncertain timing if at all) 


Silence Therapeutics: A novel cancer approach and strong purchasing power

Market cap: ~150M (of which $30-35M in cash)

Following a remarkable financial turnaround and management reshuffle, Silence Therapeutics has become a force to be reckoned with once again.  Unlike in the early days, it is the product candidates, and not RNAi trigger IP, that is the focus of the New Silence.

First and foremost is Atu027, an endothelially targeted RNAi Therapeutics aimed at preventing cancer metastasis.  The company believes that Atu027 will be most useful in combination with small molecules that aim at killing primary tumor cells and consequently is about to initiate phase Ib/phase II combination trials.

According to the information in the latest financing (which was approved today), a significant investment will be made in building a broader pipeline.  This will take advantage of the company’s three lipid-based delivery technologies: Atuplex (broad endothelial cells), DACC (lung endothelial cells), and DBTC (cells in the liver).  In general, the market cap and cash infusion position the company well to pick up some distressed RNAi and other assets.

Upcoming catalysts:

-          - Initiation of pancreatic cancer combination trial with Atu027 (H2 2013);
-          - Nominating new development candidate(s) (H2 2013);
-          - Pre-clinical data on liver delivery technology (2013);
-          - Partnering, also for non-RNAi, non-therapeutic applications


RXi Pharmaceuticals: Just dermal anti-scarring no more  

Market cap: $80-90M (of which ~$20M in cash)

RXi Pharmaceuticals is the company that popularized the self-delivering RNAi trigger concept.  Unfortunately for the company, it made a critical IP mistake of staying clear of the most potent versions it could have created with its ideas (à dsRNA length).  Furthermore, it seemed that it never was able to get anything into the clinic.

This changed last year with phase I initiation for RXI-109, a potentially superior alternative to Pfizer’s antisense-based dermal anti-scarring candidate.  However, as part of a reorganization, it essentially got rid of its R&D to focus all resources on RXI-109.

As you know, getting rid of in-house R&D is a mortal mistake if you want to be a platform-based company.  With the recent $16.4M cash infusion by OpkoHealth it will be interesting to watch whether they can become a self-delivering RNAi trigger platform-based candidate again, or whether the claimed company growth will largely be around expanding the indications of RXI-109 to other anti-fibrotic indications, especially ocular ones.

Upcoming catalyst:

-          Presentation of phase I data from RXI-109 (any day).
By Dirk Haussecker. All rights reserved.

Disclaimer: This blog is not intended for distribution to or use by any person or entity who is a citizen or resident of, or located in any locality, state, country or other jurisdiction where such distribution, publication, availability or use would be contrary to law or regulation or which would subject the author or any of his collaborators and contributors to any registration or licensing requirement within such jurisdiction. This blog expresses only my opinions, they may be flawed and are for entertainment purposes only. Opinions expressed are a direct result of information which may or may not be accurate, and I do not assume any responsibility for material errors or to provide updates should circumstances change. Opinions expressed in this blog may have been disseminated before to others. This blog should not be taken as investment, legal or tax advice. The investments referred to herein may not be suitable for you. Investments particularly in the field of RNAi Therapeutics and biotechnology carry a high risk of total loss. You, the reader must make your own investment decisions in consultation with your professional advisors in light of your specific circumstances. I reserve the right to buy, sell, or short any security including those that may or may not be discussed on my blog.