WHITEFISH, MT / June 9th , 2014 / RNA therapeutics have been growing in popularity over the past couple
years with the FDA approval of ISIS Pharmaceuticals’ (NASDAQ: ISIS) and
Sanofi SA’s (NYSE: SNY) Kynamro(R) as the first antisense drug to reach
the market and Alnylam Pharmaceuticals’ (NASDAQ: ALNY) successes in
late-stage clinical trials utilizing RNA interference ("RNAi") in its
so-called 5×15 clinical pipeline.
Unfortunately, both of these approaches have drawbacks when it comes
to clinical efficacy. Traditional antisense compounds have favorable
tissue distribution and cellular uptake, but don’t have the
intracellular potency of RNAi compounds. On the other side, the
structure of traditional RNAi compounds result in poor tissue
distribution and cellular uptake relative to antisense technologies.
In this article, we’ll take a look at a company that has bridged the
divide between antisense and RNAi by taking the best of both worlds.
Best of Both Worlds
RXi Pharmaceuticals Corp. (NASDAQ: RXII) has developed a unique platform, known as sd-rxRNA,
that bridges the gap between antisense and RNAi. The technology has a
single-stranded phosphorothioate region, a short duplex region, and
contains a variety of nuclease-stabilizing and lipophilic chemical
modifiers. These features provide both efficiency cellular uptake and
long-lasting intracellular activity.
Figure 1 – Tissue Uptake & Distribution – Source: RXi Pharmaceuticals Corp.
The efficient cellular uptake is observed both in vitro and in vivo
in tissues including the skin, retina, lung, spinal cord, and liver
(Figure 1). Since tissue distribution is defined by the administration
route and pharmacokinetic properties, efficient uptake of sd-rxRNA could
be possible in any tissue as long as the administration route permits
local delivery of the compound.
With the ability to improve tissue distribution and cellular uptake
across multiple tissue types, the platform could address most if not all
RNA-targetable indications, ranging from rare genetic disorders to
cancers. The company has already built a sizeable pipeline in areas like
dermal scarring, PVR, macular degeneration, retinoblastoma, and other
conditions (see Figure 2).
Figure 2 – RXi Pharma Clinical Pipeline – Source: RXi Pharmaceuticals Corp.
RXi Pharmaceutical’s initial proof-of-concept is its RXI-109 compound
for the treatment of dermal scarring following planned surgeries. By
reducing the expression of CTGF, a regulator of biological pathways
involved with fibrosis and scar formation, RXI-109 is expected to
significantly reduce serious scarring following a variety of different
types of surgery.
RXi Pharmaceuticals President and CEO, Dr. Geert Cauwenbergh,
commented in a July 2013 press release discussing the company’s second
Phase 1 study (RXI-109-1202), results, "These results show that
multiple intradermal injections of RXI-109 are well tolerated … results
from this second study demonstrate the mRNA for CTGF in the incisions is
reduced in a dose-dependent manner by RXI-109 as compared to placebo."
In May 2014, the company also announced positive results from its
assessment of CTGF protein levels following an intravitreal injection of
RXI-109 in the eyes of cynomolgus monkeys. This dose-range finding
study, which is part of the initial steps to build the company’s growing
ophthalmology franchise, also demonstrates the ability of the sd-rxRNA
compounds to penetrate ocular tissues.
RXi Pharmaceuticals has announced that it received a Notice of
Allowance from the U.S. Patent & Trademark Office for sd-rxRNA in
late May 2014. Broadly covering both the composition and methods used by
the platform technology, the patent protects the company’s approach of
integrating drug-like properties in RNAi compounds until the patent
expires in 2029.
"This key patent is what differentiates RXi’s technology platform
from the competition," said Dr. Cauwenbergh. "It provides us with a
powerful advantage to deliver our RNAi compounds without delivery
vehicles, which are commonly used with other siRNA compounds in clinical
development. The use of our proprietary sd-rxRNA technology platform
may lead to improved tolerability and thereby potentially broadening of
the therapeutic window for these compounds."
The patent also adds to the company’s extensive patent portfolio that
provides multiple layers of intellectual property protection for the
rxRNA and sd-rxRNA platforms, as well as for innovations in RNA delivery
technologies. The complete portfolio includes RNAi compound designs,
oligonucleotide technologies, sequences for multiple therapeutic target
genes, and therapeutic methods in treating diseases.
RXi Pharmaceuticals’ stock has moved off of its highs from earlier
this year, but its underlying platform technology and clinical pipeline
remain robust. With key patents issued on its sd-rxRNA platform, the
company is well positioned to continue developing RXI-109 as a
proof-of-concept. The platform could become significantly more valuable
with a successful drug under its belt over the coming years.
In particular, the company’s sd-rxRNA platform could be licensed to
third party drug companies interested in joint ventures pursuing other
diseases and conditions. Shareholders could benefit from the wider scope
of conditions covered, diversified pipeline of opportunities, and
ultimately potential royalty revenue. These factors make the stock worth
a second look for biotechnology investors.
For more information, see the following resources:
- Company Website
- Recent SEC Filings
Learn More about RXi Pharmaceuticals Here:
Disclaimer: Except for the historical information presented herein,
matters discussed in this release contain forward-looking statements
that are subject to certain risks and uncertainties that could cause
actual results to differ materially from any future results, performance
or achievements expressed or implied by such statements. Emerging
Growth LLC is not registered with any financial or securities regulatory
authority, and does not provide nor claims to provide investment advice
or recommendations to readers of this release. For making specific
investment decisions, readers should seek their own advice. Emerging
Growth LLC may be compensated for its services in the form of cash-based
compensation or equity securities in the companies it writes about, or a
combination of the two. For full disclosure please visit: http://secfilings.com/Disclaimer.aspx
SOURCE: Emerging Growth LLC