Overview

We are a biotechnology company focused on discovering, developing and commercializing innovative therapies based on our proprietary, next-generation RNA interference (“ RNAi ”) platform. Therapeutics that use RNAi have great promise because of their ability to “silence,” or down-regulate, the expression of a specific gene that may be over-expressed in a disease condition. Prior to September 2011, our business was operated as an unincorporated division within our former parent company. We were incorporated in Delaware as a wholly owned subsidiary of our former parent company on September 8, 2011 in preparation for our planned spin-off, which was completed on April 27, 2012. Since that date, we have operated as an independent, publicly traded company.

By utilizing the expertise in RNAi and the comprehensive RNAi platform that we have established, we believe that we have discovered and will be able to discover and develop lead compounds and progress them into and through clinical development for potential commercialization. Our proprietary therapeutic platform is comprised of novel RNAi compounds, referred to as rxRNA ^® compounds, that are distinct from, and we believe convey significant advantages over, conventional siRNA (conventionally-designed “small interfering RNA” compounds), and offer many of the properties that we believe are important to the clinical development of RNAi-based drugs. We have developed a number of unique forms of rxRNA compounds, all of which have been shown to be highly potent both in vitro and in preclinical in vivo models. These RNAi compounds include rxRNAori ^® and sd-rxRNA ^® , or “self-delivering” RNA. Based on our research, we believe that these different, novel siRNA configurations have various potential advantages for therapeutic use. These potential advantages include high potency, increased resistance to nucleases and modifications to eliminate off-target effects, and, in the case of the sd-rxRNA compounds, access to cells and tissues with no additional formulation required, and, hence, reduced cell toxicity, which is known to be an issue with unmodified siRNAs.

Our Therapeutic Pipeline

The following is a summary of our therapeutic development programs.

RXI-109 Clinical Development Program

Our lead clinical product candidate is RXI-109, a self-delivering RNAi compound (sd-rxRNA) being developed for the reduction of dermal scarring. RXI-109 is designed to reduce the expression of connective tissue growth factor (“ CTGF ”), a critical regulator of several biological pathways involved in scarring and fibrotic diseases. RXI-109 is being developed to prevent or reduce dermal scarring following surgery or trauma, as well as for the management of hypertrophic scars and keloids.

        In June 2012, we initiated our first clinical trial of RXI-109, known as Study 1201. Study 1201 was designed to evaluate the safety and tolerability of several single-dose levels of RXI-109 in humans. Study 1201 enrolled fifteen subjects in a single-center, randomized, single-dose, double-blind, ascending dose, within-subject controlled study of RXI-109 for the treatment of incision scars, during which single, intradermal injections of escalating doses were administered. Subjects received an injection of RXI-109 in two separate areas on the abdomen and placebo injections in two other areas of the abdomen, followed by a small incision at each injection site. RXI-109 was well tolerated by intradermal injection. No serious local or systemic side effects were observed in the subjects at any of the doses administered, and maximum systemic exposure after intradermal administration was assessed at approximately 5% of the total dose administered. In this study, RXI-109 showed excellent safety and tolerability with ascending single doses and significantly reduced the expression of CTGF protein in the wounded area in a dose-dependent manner 84 days after a single dose, suggesting a potent and long lasting effect on this key biomarker for abnormal scarring.

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In December 2012, we initiated a second Phase 1 clinical trial with RXI-109, known as Study 1202. Study 1202 was designed to evaluate the safety and tolerability of multi-dose administration of RXI-109 in healthy volunteers, including an evaluation of surrogate end points of clinical efficacy. In total, Study 1202 enrolled fifteen subjects (5 cohorts of 3 subjects each) in a single-center, randomized, multi-dose, double-blind, ascending dose, within-subject controlled study of RXI-109 for the treatment of incision scars. Eight small skin incisions were made in their abdomen and subjects received treatment with RXI-109 at the four incision sites on one side of the abdomen and placebo treatment at the four incision sites on the other side of the abdomen. Treatments were given by three intradermal injections over a 2-week period. Subjects were monitored for safety and local and systemic effects over a total study period of 84 days. Multiple dermal injections were well tolerated at all dose levels. Treatment with RXI-109 demonstrated a trend for dose-dependent silencing of CTGF mRNA in the treated areas, resulting in 43-50% reduction of CTGF mRNA levels compared to the placebo when measured three days after the last dose. In one of two highest-dose cohorts, the dosing period was delayed by two weeks after the incisions were made. No additional benefit was seen on mRNA reduction.

Based on the safety profile shown in our two Phase 1 clinical trials, we initiated a Phase 2 clinical trial for RXI-109 in November 2013 known as Study 1301. In this study, patients with a long hypertrophic scar in the lower abdominal area are eligible to receive scar revision surgery and subsequent treatment with RXI-109 in one of two treatment regimens. Patients will receive RXI-109 and placebo on a blinded basis at the distal ends of their revised scar, leaving a central untreated section of the scar. Each patient’s revised scar area will provide the opportunity to compare the appearance of the revised areas after treatment with RXI-109 or placebo or when left untreated. This design allows for intra-subject comparison of the three revised scar segments, thereby increasing the power of the study.

In 2014, we expect to initiate two additional Phase 2 studies. The first additional Phase 2 study will evaluate the effect of RXI-109 on the recurrence of keloids after keloid revision surgery and the second additional Phase 2 study will evaluate the effect of RXI-109 on suppressing recurrence of hypertrophic scars after bilateral scar revision surgery in the breast area.

As there are currently no Food and Drug Administration (“ FDA ”)-approved drugs to prevent scar formation, a therapeutic of this type could have great benefit for trauma and surgical patients, as a treatment during the surgical revision of existing unsatisfactory scars, and in the treatment, removal and inhibition of keloids (scars that extend beyond the original skin injury).

Other Development Programs

While focusing our efforts on our RXI-109 development program, we also intend to continue to advance additional development programs both on our own and through collaborations with academic and corporate third parties. On March 1, 2013, we entered into an asset purchase agreement with OPKO Health, Inc. (“ OPKO ”) pursuant to which we acquired substantially all of OPKO’s RNAi-related assets, including patents, licenses, clinical and preclinical data and other related assets (the “ OPKO Asset Purchase ”).

Current programs in the discovery and preclinical stages include:

Future Applications of RXI-109

Overexpression of CTGF is implicated in dermal scarring and fibrotic disease, and because of this, we believe that RXI-109 or other CTGF-targeting RNAi compounds may be able to treat other fibrotic indications, including pulmonary fibrosis, liver fibrosis, acute spinal injury, ocular scarring, joint fibrosis and vascular restenosis. If the current clinical trials of RXI-109 produce successful results in dermal anti-scarring, we may explore opportunities in these additional indications, as well as other possible dermatology applications (e.g., cutaneous scleroderma).

Market Opportunity

There are currently no FDA-approved therapeutics in the United States for the treatment and prevention of scars in the skin. However, there are over 42 million procedures in the United States each year that could potentially benefit from a therapeutic treatment that could successfully reduce or prevent scarring; thus, the market potential is quite large. In addition to cosmetic and reconstructive surgeries, medical interventions which could incorporate an anti-scarring agent include scarring that results from trauma, surgery or burns (especially relating to raised or hypertrophic scarring or contracture scarring), surgical revision of existing unsatisfactory scars, and in the treatment, removal and inhibition of keloids (scars which extend beyond the original skin injury).

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In November 2013, we signed a distribution agreement with Ethicor Ltd. (“ Ethicor ”), a UK-based unlicensed medicinal products (“ Specials ”) pharmaceutical company. The agreement provides Ethicor with the distribution rights to RXI-109 in the European Union, with the possibility to negotiate in the future to extend such rights to other regions of the world, excluding the United States, Canada and Mexico. If approved for commercialization, Ethicor will pay us a double-digit percentage of any gross profits from its sales of RXI-109. Ethicor’s distribution rights continue until the agreement is terminated; provided, however, that should we obtain marketing authorization for RXI-109 in any of the countries covered by the agreement, we have the option to terminate the agreement with respect to each such country in which marketing authorization has been obtained. Under the European medicines legislation (Directive 2001/83/EC, Article 5(1)), we expect that Ethicor will be able to supply, prior to regulatory approval, RXI-109 as a “Special” drug. A “Special” drug may be requested by an authorized health-care professional to meet the special needs of an individual patient under their direct responsibility. The collaboration is important for health-care professionals and patients who can get safe controlled early access to a development drug and is a significant milestone for the Company, not only in possible early revenue, but as increased exposure to RXI-109 may be key in accelerating the development of our drug.

Reverse Stock Split

On July 23, 2013, we effected a 1-for-30 reverse stock split of our outstanding common stock in connection with a listing of our common stock on the NASDAQ Capital Market. Stockholders who would otherwise have been entitled to fractional shares as a result of the reverse stock split received a cash payment in lieu of receiving fractional shares. Shares of common stock underlying outstanding stock options and other equity instruments were proportionately reduced and the respective exercise prices, if applicable, were proportionately increased in accordance with the terms of the agreements governing such securities. Shares of common stock reserved for issuance upon the conversion of the Company’s Series A convertible preferred stock (“ Series A Preferred Stock ”) were proportionately reduced and the respective conversion prices were proportionately increased. All share and per share amounts in the financial statements have been retroactively adjusted for all periods presented to give effect to the reverse stock split, including reclassifying an amount equal to the reduction in par value to additional paid-in capital.

Recent Business Developments

During 2013 and in the first quarter of 2014, we announced several important developments that are outlined below.

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Financial Condition

We have generated significant losses to date, have not generated any product revenue to date and may not generate product revenue in the foreseeable future, if ever. We expect to incur significant operating losses as we advance our product candidates through the drug development and regulatory process. We will need to generate significant revenues to achieve profitability and might never do so. In the absence of product revenues, our potential sources of operational funding are expected to be the proceeds from the issuance of debt, sale of equity, funded research and development payments and payments received under partnership and collaborative agreements.

On March 6, 2013, we entered into a Securities Purchase Agreement (the “ SPA ”) pursuant to which we agreed to issue 3,765,230 shares of common stock at a price of $4.35 per share (the “ Offering ”). The gross proceeds from the Offering, which closed on March 12, 2013, were approximately $16.4 million, and the net proceeds, after payment of commissions and other costs, were approximately $15.7 million. We have used the proceeds from the Offering for general corporate purposes, including the advancement of our RXI-109 program, research and development and general and administrative expenses.

We believe that our existing cash, cash equivalents and short-term investments should be sufficient to fund our operations, including the planned Phase 2 programs for RXI-109, into the second quarter of fiscal 2015. In the future, we will be dependent on obtaining funding from third parties, such as proceeds from the issuance of debt, sale of equity, funded research and development programs and payments under partnership and collaborative research and business development agreements, in order to maintain our operations and meet our obligations to licensors. There is no guarantee that debt, additional equity or other funding will be available to us on acceptable terms, or at all. If we fail to obtain additional funding when needed, we would be forced to scale back, or terminate, our operations or to seek to merge with or to be acquired by another company.

Introduction to the Field of RNAi Therapeutics

RNAi is a naturally occurring phenomenon where short, double-stranded RNA molecules interfere with the expression of targeted genes. RNAi technology takes advantage of this phenomenon and potentially allows us to effectively interfere with particular genes within living cells by designing RNA-derived molecules targeting those genes.

RNAi offers a novel approach to the drug development process because, as described below under “The RNAi Mechanism,” RNAi compounds can potentially be designed to target any one of the thousands of human genes, many of which are “undruggable” by other modalities. The specificity of RNAi is achieved by an intrinsic, well-understood biological mechanism based on designing the sequence of an RNAi compound to match the sequence of the targeted gene. The sequence of the entire human genome is now known, and the mRNA coding sequence for many proteins is already available. Supported by numerous gene-silencing reports and our own research, we believe that this sequence information can be used to design RNAi compounds to interfere with the expression of almost any specific gene.

The RNAi Mechanism

The genome is made of double-stranded DNA (the double helix) with 20,000-25,000 protein coding genes that act as instruction manuals for the production of all human proteins. Proteins are important molecules that allow cells and organisms to live and function. With rare exceptions, each cell in the human body has the entire complement of genes. However, only a subset of these genes directs the production of proteins in any particular cell type. For example, a muscle cell produces muscle-specific protein, whereas a skin cell does not.

        In order for a gene to guide the production of a protein, it must first be copied into a single-stranded chemical messenger (messenger RNA or mRNA), which is then translated into protein. RNAi is a naturally occurring process by which a particular messenger RNA can be destroyed before it is translated into protein. The process of RNAi can be artificially induced by introducing a small, double-stranded fragment of RNA corresponding to a particular messenger RNA into a cell. A protein complex within the cell called RISC (RNA-Induced Silencing Complex) recognizes this double-stranded RNA fragment and binds to it. RISC then splits the double strands apart, retaining one strand in the RISC complex. The RISC then helps this guide strand of RNA bind to and destroy its corresponding cellular messenger RNA target. Thus, RNAi provides a method to potentially block the creation of the proteins that cause disease.

Since gene expression controls most cellular processes, the ability to inhibit gene expression provides a potentially powerful tool to treat human diseases. Furthermore, since the human genome has already been decoded, and based on numerous gene-silencing reports, we believe that RNAi compounds can readily be designed to interfere with the expression of any specific gene. Based on our internal research and our review of certain scientific literature, we also believe that our RNAi platform may allow us to develop therapeutics with significant potential advantages over therapeutics developed using traditional methods, including:

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RXi’s RNAi Therapeutic Platform

RNAi Compound Design

Synthetic RNAi compounds are made from a strand or strands of RNA that are manufactured by a nucleic acid synthesizer. The synthesizer is programmed to assemble a strand of RNA of a particular sequence using primarily four nucleotide units (Adenine (“ A ”), Uracil (“ U ”), Cytidine (“ C ”) and Guanosine (“ G ”)) that match a small segment of the targeted gene. The hallmark of an RNAi compound is that it has a double-stranded region. The compounds can be of various lengths of nucleotide units (nt) and can contain various modifications of the nucleotide units or linkages. The two strands can have overhangs or blunt ends. A single strand can form an RNAi compound by forming a structure referred to as a hairpin.

The length and shape of the compound can affect the activity and hence the potency of the RNAi in cells. The first design of RNAi compounds to be pursued for development as human therapeutics were short, double-stranded RNAs that included at least one overhanging single-stranded region and limited modifications, known as small-interfering RNA, or siRNA, which we also refer to as classic siRNA.

We believe that classic siRNAs have drawbacks that may limit the usefulness of those agents as human therapeutics, and that we may be able to utilize the technologies we have licensed and developed internally to optimize RNAi compounds for use as human therapeutic agents. It is the combination of the length, the nucleotide sequence and the configuration of chemical modifications that are important for effective RNAi therapeutics.

Our internal research leads us to believe that next generation rxRNA compounds offer significant advantages over classic siRNA used by other companies developing RNAi therapeutics, highlighted by the following characteristics:

Based on our own research, we have developed a variety of novel siRNA configurations with potential advantages for therapeutic use. The first of these has been termed rxRNAori. This configuration has some similarities to classic siRNA in that it is composed of two short RNA strands. We have found that by using a somewhat longer length (25-29 bp), removing the overhangs and using proprietary chemical modification patterns, we achieve a higher hit rate of very potent (picomolar potency) compounds in a given target sequence. These rxRNAori compounds are modified to increase resistance to nucleases and to prevent off-target effects including induction of an immune response. These novel RNAi compounds are distinct from the siRNA compounds used by many other companies developing RNAi therapeutics in that they are designed specifically for therapeutic use and offer many of the properties that we believe are important to the clinical development of RNAi-based drugs.

The second novel configuration has been called “sd-rxRNA” to indicate its novel “self-delivering” properties, which make additional delivery vehicles unnecessary for efficient cellular uptake and RISC-mediated silencing. A combination of at least three characteristics is required for activity: (1) specific, proprietary chemical modifications; (2) a precise number of chemical modifications; and (3) reduction in oligonucleotide content. Kinetic analyses of fluorescently-labeled compounds demonstrate that efficient cellular internalization is observed within minutes of exposure. These molecules are taken up efficiently and cause target gene silencing in diverse cell types (cell lines and primary cells). This novel class of RNAi compounds may afford a broad opportunity for therapeutic development.

        We believe that both chemical modification and formulation of RNAi compounds may be utilized to develop RNA drugs suitable for therapeutic use. The route by which an RNAi therapeutic is brought into contact with the body depends on the intended organ or tissue to be treated. Delivery routes can be simplified into two major categories: (1) local (when a drug is delivered directly to the tissue of interest); and (2) systemic (when a drug accesses the tissue of interest through the circulatory system). Local delivery may avoid some hurdles associated with systemic approaches such as circulation clearance and tissue extravasation (crossing the endothelial barrier from the blood stream). However, the local delivery approach can only be applied to a limited number of organs or tissues ( e.g. , skin, eye, lung and potentially the central nervous system).

The key to therapeutic success with RNAi lies in delivering intact RNAi compounds to the target tissue and the interior of the target cells. To accomplish this, we have developed a comprehensive platform that includes local and systemic delivery approaches. We work with chemically synthesized RNAi compounds that are optimized for stability and efficacy and combine delivery at the site of action and formulation with delivery agents to achieve optimal delivery to specific target tissues.

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Local Delivery

sd-rxRNA molecules have unique properties that improve tissue and cell uptake. Delivery of sd-rxRNA by a local route of administration may avoid hurdles associated with systemic approaches such as rapid clearance from the bloodstream and inefficient extravasation ( e.g. , crossing the endothelial barrier from the blood stream). We have studied sd-rxRNA molecules in a rat model of dermal delivery. Direct application of sd-rxRNA with no additional delivery vehicle to the skin (incision introduced) demonstrates that target gene silencing can be measured after local administration. The dose levels required for these direct-injection methods are small and suitable for clinical development, suggesting that local delivery indications will be very accessible with the sd-rxRNA technology platform. Target tissues that are potentially accessible for local delivery using sd-rxRNA compounds include the skin, the eye, the lung, the central nervous system, mucosal tissues, sites of inflammation and tumors (direct administration).

Systemic Delivery

Systemic delivery occurs when a drug accesses the targeted tissue through the circulatory system. In some cases, such as in targeting a treatment to the liver, the optimal route of delivery may be by a systemic route. We have developed a portfolio of systemic delivery solutions utilizing our RNAi therapeutic platforms. One novel approach involves the use of sd-rxRNA compounds. The self-delivering technology introduces properties required for in vivo efficacy such as cell and tissue penetration, reduced blood clearance and improved distribution properties. Systemic delivery of these sd-rxRNAs to mice has resulted in gene-specific inhibition in the liver with no additional delivery vehicle required, albeit at high concentrations. A proof-of-concept preclinical study using rxRNA ^® in conjunction with a standard lipid-based delivery vehicle has enabled us to demonstrate gene-specific inhibition in liver at much lower doses in a mouse model after intravenous, systemic delivery. While delivery of RNAi to the liver may be critical for the treatment of many diseases, additional target tissues that are potentially accessible using rxRNA ^® compounds by systemic delivery include kidney, fat, heart, lung, bone marrow, sites of inflammation, tumors and vascular endothelium.

Intellectual Property

We protect our proprietary information by means of United States and foreign patents, trademarks and copyrights. In addition, we rely upon trade secret protection and contractual arrangements to protect certain of our proprietary information and products. We have pending patent applications that relate to potential drug targets, compounds we are developing to modulate those targets (described throughout herein as rxRNA), methods of making or using those compounds and proprietary elements of our drug discovery platform.

Much of our technology and many of our processes depend upon the knowledge, experience and skills of key scientific and technical personnel. To protect our rights to our proprietary know-how and technology, we require all employees, as well as our consultants and advisors when feasible, to enter into confidentiality agreements that require disclosure and assignment to us of ideas, developments, discoveries and inventions made by these employees, consultants and advisors in the course of their service to us, and we vigorously defend that position with partners, as well as with employees who leave the Company.

We have also obtained rights to various patents and patent applications under licenses with third parties, which require us to pay royalties or milestone payments, or both. The degree of patent protection for biotechnology products and processes, including ours, remains uncertain, both in the United States and in other important markets, because the scope of protection depends on decisions of patent offices, courts and lawmakers in these countries. There is no certainty that our existing patents or others, if obtained, will afford us substantial protection or commercial benefit. Similarly, there is no assurance that our pending patent applications or patent applications licensed from third parties will ultimately be granted as patents or that those patents that have been issued or are issued in the future will stand if they are challenged in court. We assess our license agreements on an ongoing basis, and may from time to time terminate licenses to technology that we do not intend to employ in our immunotherapy or RNAi technology platforms, or in our product discovery or development activities.

RXi RNAi Platform Patent and Patent Applications

Our portfolio includes one issued patent, claiming CTGF-targeting sd-rxRNAs for the treatment of fibrotic disorders. This patent (U.S. Patent Number 8,664,189) is scheduled to expire in 2029. The patent applications encompass what we believe to be important new RNAi compounds and their use as therapeutics, chemical modifications of RNAi compounds that improve the compounds’ suitability for therapeutic uses (including delivery) and compounds directed to specific targets ( i.e. , that address specific disease states). Any patents that may issue from these pending patent applications will, if issued, be set to expire between 2028 and 2031, not including any patent term extensions that may be afforded under the Federal Food, Drug and Cosmetic Act (and the equivalent provisions in foreign jurisdictions) for any delays incurred during the regulatory approval process relating to human drug products (or processes for making or using human drug products).

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OPKO RNAi Platform Patents and Patent Applications

The OPKO RNAi patents and patent applications encompass 12 patent families and includes 41 issued patents. The patents and patent applications cover RNAi compounds and their use as therapeutics and compounds directed to specific targets ( i.e ., that address specific disease states). The patents and any patents that may issue from the pending applications will be set to expire between 2022 and 2030, not including any patent term extensions that may be afforded under the Federal Food, Drug and Cosmetic Act (and the equivalent provisions in foreign jurisdictions) for any delays incurred during the regulatory approval process relating to human drug products (or processes for making or using human drug products).

License Agreements

We have secured exclusive and non-exclusive rights to develop RNAi therapeutics by licensing key RNAi technologies and patent rights from third parties. These rights relate to chemistry and configuration of RNAi compounds, delivery technologies of RNAi compounds to cells and therapeutic targets. As we continue to develop our own proprietary compounds, we continue to evaluate both our in-licensed portfolio as well as the field for new technologies that could be in-licensed to further enhance our intellectual property portfolio and unique position in the RNAi space.

University of Massachusetts Medical School . We hold a non-exclusive license from the University of Massachusetts Medical School (“ UMMS ”). This license grants to us rights under certain UMMS patent applications to make, use and sell products related to applications of RNAi technologies in particular fields, including HCMV and retinitis, amyotrophic lateral sclerosis, known as “ALS” or “Lou Gehrig’s Disease,” diabetes and obesity. Throughout the term of the license, we must pay UMMS an annual maintenance fee of $15,000. We also will be required to pay to UMMS customary royalties of up to 10% of: (i) any future net sales of licensed products; (ii) income received from any sublicensees under this license; and (iii) net sales of commercial clinical laboratory services, subject to a minimum royalty of $50,000 beginning in 2016. We also agreed to pay expenses incurred by UMMS in prosecuting and maintaining the licensed patents.

The UMMS license was effective on April 15, 2003, and will remain in effect until the expiration of all issued patents within the “patent rights” (as defined), unless earlier terminated in accordance with the provisions of the license. In the event that either party commits a material breach of its obligations under the UMMS license and fails to cure that breach within 60 days after receiving written notice thereof, the other party may terminate the UMMS license immediately upon written notice to the party in breach.

The UMMS license may be amended, supplemented, or otherwise modified only by signed written agreement of the parties.

Advirna. We have entered into agreements with Advirna, LLC pursuant to which Advirna assigned to us its existing patent and technology rights related to sd-rxRNA ^® technology in exchange for our agreement to pay Advirna an annual maintenance fee of $100,000 and a one-time milestone payment of $350,000 upon the issuance of the first patent with valid claims covering the assigned technology, which occurred on March 4, 2014. Additionally, we will be required to pay a 1% royalty to Advirna on any licensing revenue received by us with respect to future licensing of the assigned Advirna patent and technology rights. We also granted back to Advirna a license under the assigned patent and technology rights for fields of use outside human therapeutics and diagnostics, and issued to Advirna, upon the completion of the spin-off transaction in 2012, 1,394,997 shares of common stock.

Our rights under the Advirna agreement will expire upon the later of: (i) the expiration of the last-to-expire of the “patent rights” (as defined) included in the Advirna agreement; or (ii) the abandonment of the last-to-be abandoned of such patents, unless earlier terminated in accordance with the provisions of the agreement.

We may terminate the Advirna agreement at any time upon 90 days’ written notice to Advirna, and Advirna may terminate the agreement upon 90 days’ prior written notice in the event that we cease using commercially reasonable efforts to research, develop, license or otherwise commercialize the patent rights or “royalty-bearing products” (as defined), provided that we may refute such claim within such 90-day period by showing budgeted expenditures for the research, development, licensing or other commercialization consistent with other technologies of similar stage of development and commercial potential as the patent rights or royalty-bearing products. Further, either party at any time may provide to the other party written notice of a material breach of the agreement. If the other party fails to cure the identified breach within 90 days after the date of the notice, the aggrieved party may terminate the agreement by written notice to the party in breach.

The Advirna agreement may only be altered or supplemented by written mutual agreement by the parties.

        OPKO . In March 2013, we acquired from OPKO substantially all of its RNAi-related assets, which included patents and patent applications, licenses, clinical and preclinical data and other related assets. In exchange for the assets that we purchased from OPKO, we issued to OPKO 1,666,666 shares of our common stock and agreed to pay, if applicable: (i) up to $50,000,000 in development and commercialization milestones for the successful development and commercialization of each “Qualified Drug” (as defined in the Asset Purchase Agreement with OPKO) (collectively, the “Milestone Payments”); and (ii) royalty payments equal to: (a) a mid-single-digit percentage of “Net Sales” (as defined in the Asset Purchase Agreement) with respect to each Qualified Drug sold for an ophthalmologic use during the applicable “Royalty Period” (as defined in the Asset Purchase Agreement); and (b) a low-single-digit percentage of Net Sales with respect to each Qualified Drug sold for a non-ophthalmologic use during the applicable Royalty Period (collectively, the “Royalty Payments”). The assets purchased from OPKO are at an early stage of development, and we have established a discovery program to identify potential sd-rxRNA lead compounds and targets from these acquired RNAi-related assets.

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Research and Development

To date, our research programs have focused on identifying product candidates and optimizing the delivery method and technology necessary to make RNAi compounds available by local or systemic administration, as appropriate, for diseases for which we intend to develop an RNAi therapeutic. Since we commenced operations, research and development has comprised a significant proportion of our total operating expenses and is expected to comprise the majority of our spending for the foreseeable future.

There are risks in any new field of drug discovery that preclude certainty regarding the successful development of a product. We cannot reasonably estimate or know the nature, timing and costs of the efforts necessary to complete the development of, or the period in which material net cash inflows are expected to commence from, any product candidate.

For more information on our research and development activity, see Item 7, “Management’s Discussion and Analysis of Financial Condition and Results of Operations—Research and Development” of this annual report on Form 10-K.

Competition

We believe numerous companies are investigating or plan to investigate a variety of proposed anti-scarring therapies in clinical trials. The companies include large and small pharmaceutical, chemical and biotechnology companies, as well as universities, government agencies and other private and public research organizations. Such companies include CoDa Therapeutics, Inc., Sirnaomics, Inc., FirstString Research, Inc., Merz Pharmaceuticals, LLC, Capstone Therapeutics, Halscion, Inc., Garnet Bio Therapeutics, Inc., AkPharma Inc., Promedior, Inc., Kissei Pharmaceutical Co., Ltd., Eyegene, Derma Sciences, Inc., Healthpoint Biotherapeutics, FibroGen, Inc. and Pharmaxon. In particular, Excaliard Pharmaceuticals, Inc., which has been acquired by Pfizer, Inc., has successfully advanced an anti-CTGF antisense oligonucleotide through several Phase 1 and Phase 2 trials and has demonstrated improved scar outcome over placebo.

We believe that other companies working in the RNAi area, generally, include Alnylam Pharmaceuticals, Inc., Marina Biotech, Inc., Tacere Therapeutics, Inc., Benitec Limited, Silence Therapeutics plc, Quark Pharmaceuticals, Inc., Rosetta Genomics Ltd., Lorus Therapeutics, Inc., Tekmira Pharmaceuticals Corporation, Arrowhead Research Corporation, Regulus Therapeutics Inc. and Santaris, as well as a number of large pharmaceutical companies. Many other companies are pursuing non-RNAi-based therapies for one or more fibrotic disease indications, including ocular scarring or other indications that we may seek to pursue. See Item 1A, “Risk Factors—Risks Relating to RXi’s Business and Industry”.

Government Regulation

The United States and other developed countries extensively regulate the preclinical and clinical testing, manufacturing, labeling, storage, record-keeping, advertising, promotion, export, marketing and distribution of drugs and biologic products. The FDA regulates pharmaceutical and biologic products under the Federal Food, Drug, and Cosmetic Act, the Public Health Service Act and other federal statutes and regulations.

To obtain approval of our future product candidates from the FDA, we must, among other requirements, submit data supporting safety and efficacy for the intended indication as well as detailed information on the manufacture and composition of the product candidate. In most cases, this will require extensive laboratory tests and preclinical and clinical trials. The collection of these data, as well as the preparation of applications for review by the FDA involve significant time and expense. The FDA also may require post-marketing testing to monitor the safety and efficacy of approved products or place conditions on any approvals that could restrict the therapeutic claims and commercial applications of these products. Regulatory authorities may withdraw product approvals if we fail to comply with regulatory standards or if we encounter problems at any time following initial marketing of our products.

The first stage of the FDA approval process for a new biologic or drug involves completion of preclinical studies and the submission of the results of these studies to the FDA. These data, together with proposed clinical protocols, manufacturing information, analytical data and other information submitted to the FDA, in an investigational new drug (“ IND ”) application, must become effective before human clinical trials may commence. Preclinical studies generally involve FDA regulated laboratory evaluation of product characteristics and animal studies to assess the efficacy and safety of the product candidate.

After the IND becomes effective, a company may commence human clinical trials. These are typically conducted in three sequential phases, but the phases may overlap. Phase 1 trials consist of testing the product candidate in a small number of patients or healthy volunteers, primarily for safety at one or more doses. Phase 2 trials, in addition to safety, evaluate the efficacy of the product candidate in a patient population somewhat larger than Phase 1 trials. Phase 3 trials typically involve additional testing for safety and clinical efficacy in an expanded population at multiple test sites. A company must submit to the FDA a clinical protocol, accompanied by the approval of the Institutional Review Boards (“ IRB ”) at the institutions participating in the trials, prior to commencement of each clinical trial.

To obtain FDA marketing authorization, a company must submit to the FDA the results of the preclinical and clinical testing, together with, among other things, detailed information on the manufacture and composition of the product candidate, in the form of a new drug application (an “ NDA ”), or, in the case of a biologic, a biologics license application (a “ BLA ”).

The amount of time taken by the FDA for approval of an NDA or BLA will depend upon a number of factors, including whether the product candidate has received priority review, the quality of the submission and studies presented, the potential contribution that the compound will make in improving the treatment of the disease in question and the workload at the FDA.

The FDA may, in some cases, confer upon an investigational product the status of a fast track product. A fast track product is defined as a new drug or biologic intended for the treatment of a serious or life threatening condition that demonstrates the potential to address unmet medical needs for this condition. The FDA can base approval of an NDA or BLA for a fast track product on an effect on a surrogate endpoint, or on another endpoint that is reasonably likely to predict clinical benefit. If a preliminary review of clinical data suggests that a fast track product may be effective, the FDA may initiate review of entire sections of a marketing application for a fast track product before the sponsor completes the application.

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We anticipate that our products will be manufactured by our strategic partners, licensees or other third parties. Before approving an NDA or BLA, the FDA will inspect the facilities at which the product is manufactured and will not approve the product unless the manufacturing facilities are in compliance with the FDA’s current good manufacturing practices (“ cGMP ”), which are regulations that govern the manufacture, holding and distribution of a product. Manufacturers of biologics also must comply with the FDA’s general biological product standards. Our manufacturers also will be subject to regulation under the Occupational Safety and Health Act, the Nuclear Energy and Radiation Control Act, the Toxic Substance Control Act and the Resource Conservation and Recovery Act and other applicable environmental statutes. Following approval, the FDA periodically inspects drug and biologic manufacturing facilities to ensure continued compliance with the good manufacturing practices regulations. Our manufacturers will have to continue to comply with those requirements. Failure to comply with these requirements subjects the manufacturer to possible legal or regulatory action, such as suspension of manufacturing or recall or seizure of product. Adverse patient experiences with the product must be reported to the FDA and could result in the imposition of marketing restrictions through labeling changes or market removal. Product approvals may be withdrawn if compliance with regulatory requirements is not maintained or if problems concerning safety or efficacy of the product occur following approval.

The labeling, advertising, promotion, marketing and distribution of a drug or biologic product also must be in compliance with FDA and Federal Trade Commission requirements which include, among others, standards and regulations for off-label promotion, industry sponsored scientific and educational activities, promotional activities involving the internet, and direct-to-consumer advertising. We also will be subject to a variety of federal, state and local regulations relating to the use, handling, storage and disposal of hazardous materials, including chemicals and radioactive and biological materials. In addition, we will be subject to various laws and regulations governing laboratory practices and the experimental use of animals. In each of these areas, as above, the FDA has broad regulatory and enforcement powers, including the ability to levy fines and civil penalties, suspend or delay issuance of product approvals, seize or recall products and deny or withdraw approvals.

We will also be subject to a variety of regulations governing clinical trials and sales of our products outside the United States. Whether or not FDA approval has been obtained, approval of a product candidate by the comparable regulatory authorities of foreign countries and regions must be obtained prior to the commencement of marketing the product in those countries. The approval process varies from one regulatory authority to another and the time may be longer or shorter than that required for FDA approval. In the European Union, Canada and Australia, regulatory requirements and approval processes are similar, in principle, to those in the United States.

Environmental Compliance

Our research and development activities involve the controlled use of potentially harmful biological materials as well as hazardous materials, chemicals and various radioactive compounds. We are subject to federal, state and local laws and regulations governing the use, storage, handling and disposal of these materials and specific waste products. We are also subject to numerous environmental, health and workplace safety laws and regulations, including those governing laboratory procedures, exposure to blood-borne pathogens and the handling of bio-hazardous materials. The cost of compliance with these laws and regulations could be significant and may adversely affect capital expenditures to the extent we are required to procure expensive capital equipment to meet regulatory requirements.

Human Resources

As of March 15, 2014, we had twelve full-time employees, eight of whom were engaged in research and development, and four of whom were engaged in management, administration and finance. None of our employees is represented by a labor union or covered by a collective bargaining agreement, nor have we experienced any work stoppages.