Prospectus Filed Pursuant to Rule 424(b)(3)

We have entered into a sales agreement with Cowen and Company, LLC, relating to shares of our common stock offered by this prospectus. In accordance with the terms of the sales agreement, we may offer and sell shares of our common stock having an aggregate offering price of up to $40,000,000 from time to time through Cowen and Company, LLC, acting as our agent.

Our common stock is listed on the NASDAQ Global Market under the symbol “SCYX.” The last reported sale price of our common stock on November 16, 2015, was $7.00 per share.

Upon our delivery of a placement notice and subject to the terms and conditions of the sales agreement, Cowen may sell our common stock by methods deemed to be an “at the market offering” as defined in Rule 415 promulgated under the Securities Act of 1933, as amended, or the Securities Act, including sales made directly on The NASDAQ Global Market, on any other existing trading market for our common stock or to or through a market maker. In addition, with our prior written approval, Cowen may also sell our common stock by any other method permitted by law, including in negotiated transactions. Cowen will act as sales agent using its commercially reasonable efforts consistent with its normal trading and sales practices and applicable state and federal laws, rules and regulations and the rules of The NASDAQ Stock Market.

We will pay Cowen a commission equal to 3% of the gross sales price per share sold through Cowen acting as agent pursuant to the sales agreement. In connection with the sale of our common stock on our behalf, Cowen will be deemed to be an “underwriter” within the meaning of the Securities Act and the compensation of Cowen will be deemed to be underwriting commissions or discounts. We have also agreed to provide indemnification and contribution to Cowen with respect to certain liabilities, including liabilities under the Securities Act or the Securities Exchange Act of 1934, as amended, or the Exchange Act. See “Plan of Distribution” on page 10 of this prospectus.

Investing in our common stock involves a high degree of risk. Before making an investment decision, please read the information under the heading “Risk Factors” beginning on page 4 of this prospectus and in the documents incorporated by reference into this prospectus.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

This prospectus is part of a registration statement that we have filed with the Securities and Exchange Commission, or SEC, utilizing a “shelf” registration process. Under the shelf registration statement we may offer shares of our common stock, preferred stock, debt securities and warrants, including common stock or preferred stock upon conversion of debt securities, common stock upon conversion of preferred stock, or common stock, preferred stock or debt securities upon the exercise of warrants, having an aggregate offering price of up to $150,000,000. Under this prospectus, we may offer shares of our common stock having an aggregate offering price of up to $40,000,000 from time to time at prices and on terms to be determined by market conditions at the time of offering.

We provide information to you about this offering of shares of our common stock in this prospectus, which describes the specific details regarding this offering. If information in this prospectus is inconsistent with documents incorporated by reference in this prospectus filed prior to the date of this prospectus, you should rely on this prospectus. However, if any statement in one of these documents is inconsistent with a statement in another document having a later date—for example, a document incorporated by reference in this prospectus—the statement in the document having the later date modifies or supersedes the earlier statement as our business, financial condition, results of operations and prospects may have changed since the earlier dates.

You should rely only on the information contained in, or incorporated by reference into, this prospectus and in any free writing prospectus that we may authorize for use in connection with this offering. We have not, and Cowen and Company, LLC, or Cowen, has not, authorized any other person to provide you with different information. If anyone provides you with different or inconsistent information, you should not rely on it. We and Cowen take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. We are not, and Cowen is not, making an offer to sell or soliciting an offer to buy our securities in any jurisdiction in which an offer or solicitation is not authorized or in which the person making that offer or solicitation is not qualified to do so or to anyone to whom it is unlawful to make an offer or solicitation. You should assume that the information appearing in this prospectus, the documents incorporated by reference into this prospectus, and in any free writing prospectus that we may authorize for use in connection with this offering, is accurate only as of the date of those respective documents. Our business, financial condition, results of operations and prospects may have changed since those dates. You should read this prospectus, the documents incorporated by reference into this prospectus, and any free writing prospectus that we may authorize for use in connection with this offering, in their entirety before making an investment decision. You should also read and consider the information in the documents to which we have referred you in the sections of this prospectus entitled “Where You Can Find More Information” and “Incorporation of Certain Information by Reference.”

We are offering to sell, and seeking offers to buy, shares of common stock only in jurisdictions where offers and sales are permitted. The distribution of this prospectus and the offering of our common stock in certain jurisdictions may be restricted by law. Persons outside the United States who come into possession of this prospectus must inform themselves about, and observe any restrictions relating to, the offering of our common stock and the distribution of this prospectus outside the United States. This prospectus does not constitute, and may not be used in connection with, an offer to sell, or a solicitation of an offer to buy, any securities offered by this prospectus by any person in any jurisdiction in which it is unlawful for such person to make such an offer or solicitation.

We obtained the industry and market data in this prospectus from our own research as well as from industry and general publications, surveys and studies conducted by third parties. These data involve a number of assumptions and limitations, and you are cautioned not to give undue weight to such estimates. In addition, projections, assumptions and estimates of our future performance and the future performance of the industry in which we operate is necessarily subject to a high degree of uncertainty and risk due to a variety of factors, including those described in “Risk Factors” and elsewhere in this prospectus. These and other factors could cause results to differ materially from those expressed in the estimates made by the independent parties and by us.

PROSPECTUS SUMMARY

This summary highlights selected information contained elsewhere in this prospectus or incorporated by reference in this prospectus, and does not contain all of the information that you need to consider in making your investment decision. You should carefully read the entire prospectus and any related free writing prospectus, including the risks of investing in our securities discussed under the heading “Risk Factors” contained in this prospectus and any related free writing prospectus, and under similar headings in the other documents that are incorporated by reference into this prospectus. You should also carefully read the information incorporated by reference into this prospectus, including our financial statements, and the exhibits to the registration statement of which this prospectus is a part.

References in this prospectus to “SCYNEXIS”, “the Company,” “we”, “us” and “our” refer to SCYNEXIS, Inc., a Delaware corporation, and its consolidated subsidiaries, if any, unless otherwise specified.

SCYNEXIS, Inc.

Overview

SCYNEXIS is a pharmaceutical company committed to the development and commercialization of novel anti-infectives to address significant unmet therapeutic needs. We are developing our lead product candidate, SCY-078, as a novel oral and intravenous (IV) drug for the treatment of serious and life-threatening invasive fungal infections in humans. SCY-078 has been shown to be effective in vitro and in vivo in animal studies against a broad range of Candida and Aspergillus species, including drug resistant strains. These important pathogens account for approximately 85% of invasive fungal infections in the United States and Europe. SCY-078 was shown to be sufficiently safe and well-tolerated in multiple Phase 1 studies to support progression to Phase 2 studies. We are currently conducting a multicenter Phase 2 study with primary endpoints of safety, tolerability, and pharmacokinetics of the oral formulation of SCY-078 as step-down treatment in patients initially treated with echinocandin therapy for invasive Candida infections. Enrollment into the study continues but has been slower than anticipated. New investigational sites have been opened in the US and we are opening additional investigational sites in Latin America and Europe. Investigational sites are currently operating under the latest protocol amendment, which was designed to facilitate enrollment, and we continue to consider whether further protocol amendments may be appropriate. These measures are expected to increase enrollment into the study. In addition, as we collect data on the enrolled patients, we will continue to assess the actual number of patients required to achieve the study objectives. We expect to complete the study and to report top line data in the first half of 2016. We also recently initiated enrollment in the first Phase 1 study of an IV formulation of SCY-078.

We are also planning to investigate the potential clinical utility of SCY-078 in other areas of unmet medical need such as genital infections in women caused by Candida spp. (vulvovaginal candidiasis, or VVC). VVC is a highly prevalent condition with limited therapeutic options for infections caused by azole-resistant Candida spp. We are planning to commence a Phase 2 study evaluating the safety and efficacy of orally administered SCY-078 in this indication during the fourth quarter of 2015. The data from this study is also expected to provide a confirmation of the potential therapeutic effect of orally administered SCY-078 in a clinical condition caused by Candida spp. and, along with the other clinical and nonclinical data from ongoing and planned activities, will contribute to the package of information that will support subsequent phases of development of SCY-078. Prior to our strategic focus on the development of SCY-078 for the treatment of invasive fungal infections, our drug discovery initiatives produced clinical and preclinical programs based on the use of cyclophilin inhibitors to treat viral diseases, which we have licensed to partners for continued development and commercialization. In addition to pursuing the development of SCY-078, we have additional compounds similar to SCY-078 and related expertise that we may use to expand our antifungal portfolio.

Company Information

We were originally incorporated in Delaware in November 1999 as ScyRex, Inc. We subsequently changed our name to SCYNEXIS Chemistry & Automation, Inc. in April 2000 and to SCYNEXIS, Inc. in June 2002. Our principal executive offices are located at 101 Hudson Street, Suite 3610, Jersey City, NJ 07302-6548, and our telephone number is (201) 884-5485. Our website address is www.scynexis.com. The information contained on our website is not incorporated by reference into this prospectus, and you should not consider any information contained on, or that can be accessed through, our website as part of this prospectus or in deciding whether to purchase our securities.

Risk Factors Associated with Our Business

Our business is subject to numerous risks, as more fully described in the section entitled “Risk Factors” immediately following this prospectus summary. You should read these risks, and the risks incorporated by reference into this prospectus, before you invest in our common stock. In particular, our risks include, but are not limited to, the following:

•

we have never been profitable, we have no products approved for commercial sale, and to date we have not generated any revenue from product sales; as a result, our ability to curtail our losses and reach profitability is unproven, and we may never achieve or sustain profitability;

•

we expect a number of factors to cause our operating results to fluctuate on a quarterly and annual basis, which may make it difficult to predict our future performance;

•

we may continue to require substantial additional capital, and if we are unable to raise capital when needed we would be forced to delay, reduce or eliminate our product development programs;

•

historically we have devoted a majority of our resources and efforts to providing research and development services to other companies and we have derived substantially all of our revenue from providing these services; however, in July 2015, we completed the divestment of our contract research and development services business and have shifted our focus to developing our own drug candidate SCY-078;

•

we expect the divestiture of our contract research and development services business to result in a decrease of our reported revenues in 2015 and in an increase in our net loss in 2015;

•

we cannot be certain that SCY-078 will receive regulatory approval, and without regulatory approval we will not be able to market SCY-078. Regulatory approval is a lengthy, expensive and uncertain process;

•

although the oral form of SCY-078 has been granted Qualified Infectious Disease Product, or QIDP, designation, this does not guarantee that the length of the U.S. Food and Drug Administration, or FDA, review process will be significantly shorter than otherwise, or that SCY-078 will ultimately be approved by the FDA;

•

delays in the enrollment, including delays in the implementation of any amendments to the Phase 2 study’s protocol enrollment criteria, or delays in the completion of or the termination of our Phase 2 clinical trial (or future clinical trials) could result in increased costs to us and could delay or limit our ability to obtain regulatory approval for SCY-078 or any future product candidates;

•

clinical failure can occur at any stage of clinical development. Because the results of earlier clinical trials are not necessarily predictive of future results, any product candidate we or our current or potential future partners advance through clinical trials may not have favorable results in later clinical trials or receive regulatory approval;

•

we have limited experience in conducting clinical trials and has never submitted an NDA before, and we may be unable to do so for SCY-078 or any future product candidate we may seek to develop;

•

if SCY-078 or any other future product candidates for which we receive regulatory approval do not achieve broad market acceptance, the revenue that is generated from their sales will be limited;

•

a significant use of antifungal drugs consists of treatment due to the presence of symptoms before diagnosis of the invasive fungal infections, and if recently approved diagnostic tools, or additional tools currently under development, for the quick diagnosis of invasive fungal infections are broadly used in the marketplace, the number of treatments using antifungal drugs may decrease significantly, decreasing the potential market for SCY-078; and

•

if resistance to SCY-078 develops quickly or cross resistance with echinocandins becomes more common, our business will be harmed.

The Offering


Common stock offered by us:		Shares of our common stock having an aggregate offering price of up to $40,000,000.

Common stock to be outstanding after this offering:		Up to 19,619,885 shares (as more fully described in the notes following this table), assuming sales of 5,714,286 shares of our common stock in this offering at an offering price of $7.00 per share, which was the last reported sale price of our common stock on the NASDAQ Global Market on November 16, 2015. The actual number of shares issued will vary depending on the sales price under this offering.

Manner of offering:		“At-the-market” offering that may be made from time to time through our sales agent, Cowen and Company, LLC. See “Plan of Distribution” on page 10.

Use of Proceeds:		We intend to use the net proceeds from this offering, if any, for working capital and general corporate purposes, including research and development expenses and capital expenditures. See “Use of Proceeds” on page 6.

Risk Factors:		You should read the “Risk Factors” section of this prospectus and in the documents incorporated by reference in this prospectus for a discussion of factors to consider before deciding to purchase shares of our common stock.

NASDAQ Global Market Symbol:		“SCYX”

The number of our shares of common stock outstanding is based on 13,905,599 shares of common stock outstanding as of September 30, 2015, and excludes the following:

•

1,207,697 shares issuable upon the exercise of outstanding stock options at a weighted average exercise price of $9.04 per share;

•

889,445 additional shares reserved for future issuance under our equity incentive plans;

•

50,283 additional shares reserved for future issuance under our employee stock purchase plan;

•

14,033 shares issuable upon the exercise of outstanding warrants at a weighted average exercise price of $ 45.61 per share.

You should consider carefully the risks described below and discussed under the section captioned “Risk Factors” contained in our annual report on Form 10-K for the year ended December 31, 2014, and in our subsequent quarterly reports on Form 10-Q as updated by our subsequent filings under the Securities Exchange Act of 1934, as amended, or the Exchange Act, each of which is incorporated by reference in this prospectus in their entirety, together with other information in this prospectus, and the information and documents incorporated by reference in this prospectus, and any free writing prospectus that we have authorized for use in connection with this offering before you make a decision to invest in our common stock. If any of the following events actually occur, our business, operating results, prospects or financial condition could be materially and adversely affected. This could cause the trading price of our common stock to decline and you may lose all or part of your investment. The risks below and incorporated by reference in this prospectus are not the only ones we face. Additional risks not currently known to us or that we currently deem immaterial may also affect our business operations. Please also read carefully the section below entitled “Special Note Regarding Forward-Looking Statements.”

Our business is subject to numerous risks. You should read these risks before you invest in our common stock. In particular, our risks include, but are not limited to, the following, which are more fully set forth in our Quarterly Report on Form 10-Q for the quarter ended September 30, 2015, filed with the SEC on November 13, 2015, which are incorporated by reference here:

Our management team may invest or spend the proceeds of this offering in ways with which you may not agree or in ways which may not yield a significant return.

Our management will have broad discretion over the use of proceeds from this offering. The net proceeds from this offering will be used for working capital and general corporate purposes, including research and development expenses and capital expenditures. Our management will have considerable discretion in the application of the net proceeds, and you will not have the opportunity, as part of your investment decision, to assess whether the proceeds are being used appropriately. The net proceeds may be used for corporate purposes that do not increase our operating results or enhance the value of our common stock.

You may experience future dilution as a result of future equity offerings.

To raise additional capital, we may in the future offer additional shares of our common stock or other securities convertible into or exchangeable for our common stock at prices that may not be the same as the price per share in this offering. We may sell shares or other securities in any other offering at a price per share that is less than the price per share paid by investors in this offering, and investors purchasing shares or other securities in the future could have rights superior to existing stockholders. The price per share at which we sell additional shares of our common stock, or securities convertible or exchangeable into common stock, in future transactions may be higher or lower than the price per share paid by investors in this offering.

This prospectus and the documents we have filed with the SEC that are incorporated by reference contain “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933, as amended, or the Securities Act, and Section 21E of the Securities Exchange Act of 1934, as amended, or the Exchange Act. These statements relate to future events or to our future operating or financial performance and involve known and unknown risks, uncertainties and other factors which may cause our actual results, performance or achievements to be materially different from any future results, performances or achievements expressed or implied by the forward-looking statements. Forward-looking statements include, but are not limited to, statements about:

In some cases, you can identify forward-looking statements by terms such as “may,” “will,” “should,” “could,” “would,” “expect,” “plan,” “anticipate,” “believe,” “estimate,” “project,” “predict,” “potential” and similar expressions intended to identify forward-looking statements. These statements reflect our current views with respect to future events and are based on assumptions and are subject to risks and uncertainties. Given these uncertainties, you should not place undue reliance on these forward-looking statements. We discuss in greater detail many of these risks under the heading “Risk Factors” contained in this prospectus, in any free writing prospectuses we may authorize for use in connection with a specific offering, and in our most recent annual report on Form 10-K and in our most recent quarterly report on Form 10-Q, as well as any amendments thereto reflected in subsequent filings with the SEC, which are incorporated by reference into this prospectus in their entirety. Also, these forward-looking statements represent our estimates and assumptions only as of the date of the document containing the applicable statement. Unless required by law, we undertake no obligation to update or revise any forward-looking statements to reflect new information or future events or developments. Thus, you should not assume that our silence over time means that actual events are bearing out as expressed or implied in such forward-looking statements. You should read this prospectus, together with the documents we have filed with the SEC that are incorporated by reference and any free writing prospectus that we may authorize for use in connection with this offering completely and with the understanding that our actual future results may be materially different from what we expect. We qualify all of the forward-looking statements in the foregoing documents by these cautionary statements.

The amount of proceeds from this offering will depend upon the number of shares of our common stock sold and the market price at which they are sold. There can be no assurance that we will be able to sell any shares under or fully utilize the sales agreement with Cowen as a source of financing. We intend to use the net proceeds, if any, from this offering for working capital and general corporate purposes, including research and development expenses and capital expenditures.

The amounts and timing of our actual expenditures will depend on numerous factors, including our development and commercialization efforts, as well as the amount of cash used in our operations. We therefore cannot estimate with certainty the amount of net proceeds to be used for the purposes described above. We may find it necessary or advisable to use the net proceeds for other purposes, and we will have broad discretion in the application of the net proceeds. Pending the uses described above, we plan to invest the net proceeds from this offering in short-term, investment-grade, interest-bearing securities.

If you invest in our common stock, your interest will be diluted immediately to the extent of the difference between the public offering price and the adjusted net tangible book value per share of our common stock after this offering.

Our net tangible book value on September 30, 2015, was approximately $50.0 million, or $3.59 per share. “Net tangible book value” is total assets minus the sum of liabilities and intangible assets. “Net tangible book value per share” is net tangible book value divided by the total number of shares outstanding.

After giving effect to the sale of $40,000,000 of common stock in this offering at an assumed offering price of $7.00 per share, which was the closing price of our common stock as reported on NASDAQ Global Market on November 16, 2015, and after deducting estimated offering commissions and expenses payable by us, our net tangible book value as of September 30, 2015, would have been approximately $88.3 million, or $4.51 per share of common stock. This represents an immediate increase in net tangible book value of $0.92 per share to our existing stockholders and an immediate dilution in net tangible book value of

$2.49 per share to investors participating in this offering. The following table illustrates this dilution per share to investors participating in this offering:

The above illustration of dilution per share to investors participating in this offering assumes no exercise of outstanding options to purchase our common stock or outstanding warrants to purchase shares of our common stock.

The number of our shares of common stock outstanding is based on 13,905,599 shares of common stock outstanding as of September 30, 2015, and excludes the following:

To the extent that outstanding options or warrants are exercised, new options or other equity grants are issued under our incentive compensation plans, shares of common stock are sold under our employee stock purchase plan or we otherwise issue additional shares of common stock in the future, there will be further dilution to investors participating in this offering.

The following description of our capital stock does not purport to be complete and is subject in all respects to applicable Delaware law and to the provisions of our amended and restated certificate of incorporation, and our amended and restated bylaws.

Our amended and restated certificate of incorporation provides for common stock and authorized shares of undesignated preferred stock, the rights, preferences and privileges of which may be designated from time to time by our board of directors. As of October 30, 2015, our authorized capital stock consists of 130,000,000 shares, all with a par value of $0.001 per share, of which 125,000,000 shares are designated as common stock and 5,000,000 shares are designated as preferred stock.

Each holder of our common stock is entitled to one vote for each share of common stock held on all matters submitted to a vote of stockholders, except as otherwise expressly provided in our amended and restated certificate of incorporation or required by applicable law. Cumulative voting for the election of directors is not provided for in our amended and restated certificate of incorporation, which means that the holders of a majority of our shares of common stock can elect all of the directors then standing for election.

Dividends and Distributions. Subject to preferences that may apply to any shares of preferred stock outstanding at the time, the holders of outstanding shares of our common stock are entitled to receive dividends out of funds legally available at the times and in the amounts that our board of directors may determine.

Liquidation Rights. Upon our liquidation, dissolution or winding-up, the assets legally available for distribution to our stockholders would be distributable ratably among the holders of our common stock and any participating preferred stock outstanding at that time after payment of liquidation preferences, if any, on any outstanding shares of preferred stock and payment of other claims of creditors. The rights, preferences, and privileges of holders of our common stock are subject to, and may be adversely affected by, the rights of holders of shares of any series of preferred stock that we may designate and issue in the future.

Preemptive or Similar Rights. Our common stock is not entitled to preemptive rights and is not subject to conversion, redemption or sinking fund provisions.

Our board of directors is authorized, subject to limitations prescribed by Delaware law, to issue up to 5,000,000 shares of preferred stock in one or more series, to establish from time to time the number of shares to be included in each series and to fix the designation, powers, preferences and rights of the shares of each series and any of its qualifications, limitations or restrictions. Our board of directors can also increase or decrease the number of shares of any series of preferred stock, but not below the number of shares of that series then outstanding, without any further vote or action by the our stockholders. Our board of directors may authorize the issuance of preferred stock with voting or conversion rights that could adversely affect the voting power or other rights of the holders of our common stock. The issuance of preferred stock, while providing flexibility in connection with possible acquisitions and other corporate purposes, could, among other things, have the effect of delaying, deferring, discouraging or preventing a change in control or other corporate action and may adversely affect the market price of our common stock and the voting and other rights of the holders of our common stock.

As of October 30, 2015, we had outstanding warrants to purchase an aggregate of 14,033 shares of our common stock with an exercise price of $45.61 per share. Each of these warrants has a net exercise provision under which the holder, in lieu of payment of the exercise price in cash, can surrender the warrant and receive a net number of shares of common stock based on the fair market value of such stock at the time of exercise of the warrant after deduction of the aggregate exercise price. Unless earlier exercised, these warrants will expire on the five year anniversary of our initial public offering.

We are party to an investor rights agreement which provides certain holders of shares of our common stock with certain registration rights, as set forth below. The registration of shares of our common stock pursuant to the exercise of registration rights described below would enable the holders to sell these shares without restriction under the Securities Act of 1933, as amended, or the Securities Act, when the applicable registration statement is declared effective. We will pay the registration expenses, other than underwriting discounts and commissions, of the shares registered pursuant to the demand, piggyback and Form S-3 registrations described below.

Generally, in an underwritten offering, the underwriter has the right, subject to specified conditions, to limit the number of shares such holders may include. The demand, piggyback and Form S-3 registration rights described below will expire the later of (1) three years after the effective date of the registration statement in connection with our initial public offering, or (2) with respect to each stockholder, at such time as the (A) our capital stock is publicly traded and (B) such stockholder holds less than one percent (1%) of the our common stock outstanding and is entitled to sell all of its shares pursuant to Rule 144 of the Securities Act during any 90 day period.

Certain holders of shares of our common stock are entitled to certain demand registration rights. At any time before the expiration of the registration rights, the holders of forty percent (40%) of these shares may request that we file a registration statement having an aggregate offering price to the public of not less than $5.0 million to register all or a portion of their shares.

In the event that we propose in the future to register any of our securities under the Securities Act either for our own account or for the account of other security holders, certain holders of our common stock will be entitled to certain “piggyback” registration rights allowing them to include their shares in the registration, subject to certain marketing and other limitations. As a result, whenever we propose to file a registration statement under the Securities Act including a registration statement on Form S-3 as discussed below, other than with respect to a demand registration or a registration statement on Forms S-4 or S-8, the holders of these shares are entitled to notice of the registration and have the right, subject to limitations that the underwriters may impose on the number of shares included in the registration, to include their shares in the registration.

Certain holders of shares of our common stock are entitled to certain Form S-3 registration rights. These holders may make a request that we register their shares on Form S-3 if we are qualified to file a registration statement on Form S-3. The request for registration on Form S-3 must cover securities the aggregate offering price of which, before payment of underwriting discounts and commissions, is at least $1,000,000.

Because our stockholders do not have cumulative voting rights, our stockholders holding a majority of the voting power of our shares of common stock outstanding will be able to elect all of our directors. Our amended and restated certificate of incorporation and amended and restated bylaws provide that all stockholder actions must be effected at a duly called meeting of stockholders and not by consent in writing. A special meeting of stockholders may be called only by a majority of our whole board of directors, the chair of our board of directors, or our chief executive officer.

Our amended and restated certificate of incorporation further provides that the affirmative vote of holders of at least sixty-six and two-thirds percent (66-2/3%) of the voting power of all of the then outstanding shares of voting stock, voting as a single class, are required to amend certain provisions of our certificate of incorporation, including provisions relating to the size of the board, removal of directors, special meetings, actions by written consent and cumulative voting. The affirmative vote of holders of at least sixty-six and two-thirds percent (66-2/3%) of the voting power of all of the then outstanding shares of voting stock, voting as a single class, is required to amend or repeal our bylaws, although our bylaws may be amended by a simple majority vote of our board of directors.

The foregoing provisions will make it more difficult for our existing stockholders to replace our board of directors as well as for another party to obtain control of our company by replacing our board of directors. Since our board of directors has the power to retain and discharge our officers, these provisions could also make it more difficult for existing stockholders or another party to effect a change in management. In addition, the authorization of undesignated preferred stock makes it possible for our board of directors to issue preferred stock with voting or other rights or preferences that could impede the success of any attempt to change the control of our company.

These provisions are intended to enhance the likelihood of continued stability in the composition of our board of directors and its policies and to discourage certain types of transactions that may involve an actual or threatened acquisition of our company. These provisions are also designed to reduce our vulnerability to an unsolicited acquisition proposal and to discourage certain tactics that may be used in proxy rights. However, these provisions could have the effect of discouraging others from making tender offers for our shares and may have the effect of deterring hostile takeovers or delaying changes in control of our company or our management. As a consequence, these provisions also may inhibit fluctuations in the market price of our stock that could result from actual or rumored takeover attempts.

We are subject to Section 203 of the Delaware General Corporation Law, which prohibits a Delaware corporation from engaging in any business combination with any interested stockholder for a period of three years after the date that such stockholder became an interested stockholder, with the following exceptions:

In general, Section 203 defines an “interested stockholder” as an entity or person who, together with the person’s affiliates and associates, beneficially owns, or within three years prior to the time of determination of interested stockholder status did own, 15% or more of the outstanding voting stock of the corporation.

Reference is made to the information regarding our limitations on liability and indemnification under the heading “Executive Compensation—Limitation on Liability and Indemnification Matters” in Part III, Item 11 of our Form 10-K as filed with the SEC on March 30, 2015, which information is hereby incorporated by reference.

Our common stock is listed on The NASDAQ Global Market under the trading symbol “SCYX.” The applicable prospectus supplement will contain information, where applicable, as to any other listing, if any, on The NASDAQ Global Market or any securities market or other exchange of the other securities covered by such prospectus supplement.

Our transfer agent and registrar for our common stock is American Stock Transfer & Trust Company, LLC. The transfer agent’s address is 6201 15^th Avenue, Brooklyn, New York 11219.

We have entered into a sales agreement with Cowen and Company, LLC, or Cowen, under which we may issue and sell from time to time up to $40,000,000 of our common stock through Cowen as our sales agent. Sales of our common stock, if any, will be made at market prices by any method that is deemed to be an “at the market offering” as defined in Rule 415 under the Securities Act, including sales made directly on The NASDAQ Global Market and any other trading market for our common stock, and sales to or through a market maker other than on an exchange. In addition, with our prior written consent, Cowen may also sell our common stock in negotiated transactions.

Cowen will offer our common stock subject to the terms and conditions of the sales agreement on a daily basis or as otherwise agreed upon by us and Cowen. We will designate the maximum amount of common stock to be sold through Cowen on a daily basis or otherwise determine such maximum amount together with Cowen. Subject to the terms and conditions of the sales agreement, Cowen will use its commercially reasonable efforts to sell on our behalf all of the shares of common stock requested to be sold by us. We may instruct Cowen not to sell common stock if the sales cannot be effected at or above the price designated by us in any such instruction. We or Cowen may suspend the offering of our common stock being made through Cowen under the sales agreement upon proper notice to the other party. We and Cowen each have the right, by giving written notice as specified in the sales agreement, to terminate the sales agreement in each party’s sole discretion at any time.

The aggregate compensation payable to Cowen as sales agent will be 3% of the gross sales price of the shares sold through it pursuant to the sales agreement.

The remaining sales proceeds, after deducting any expenses payable by us and any transaction fees imposed by any governmental, regulatory, or self-regulatory organization in connection with the sales, will equal our net proceeds for the sale of such common stock.

Cowen will provide written confirmation to us following the close of trading on The NASDAQ Global Market each day in which common stock is sold through it as sales agent under the sales agreement. Each confirmation will include the number of shares of common stock sold through it as sales agent on that day, the gross sales price per share, the net proceeds to us and the compensation payable by us to Cowen.

We will report at least quarterly the number of shares of common stock sold through Cowen under the sales agreement, the net proceeds to us and the compensation paid by us to Cowen in connection with the sales of common stock.

Settlement for sales of common stock will occur, unless the parties agree otherwise, on the third business day that is also a trading day following the date on which any sales were made in return for payment of the net proceeds to us. There is no arrangement for funds to be received in an escrow, trust or similar arrangement.

In connection with the sale of common stock on our behalf, Cowen will be deemed to be an “underwriter” within the meaning of the Securities Act and the compensation of Cowen will be deemed to be underwriting commissions or discounts. We have agreed in the sales agreement to provide indemnification and contribution to Cowen against certain liabilities, including liabilities under the Securities Act. In addition, we have agreed, under certain circumstances, to reimburse a portion of the expenses of Cowen in connection with this offering in an amount not to exceed $50,000.

As sales agent, Cowen will not engage in any transactions that stabilize our common stock. To the extent required by Regulation M, Cowen will not engage in any market making activities involving our common stock while the offering is ongoing under this prospectus.

We estimate that the total expenses of the offering payable by us, excluding commissions payable to Cowen under the sales agreement, will be approximately $480,000.

This summary of the material provisions of the sales agreement does not purport to be a complete statement of its terms and conditions. A copy of the sales agreement is filed with the SEC and is incorporated by reference into the registration statement of which this prospectus is a part. See “Where You Can Find More Information” below.

Cooley LLP, Palo Alto, California, has passed upon the validity of the shares of our common stock offered hereby. Cowen and Company, LLC is being represented by DLA Piper LLP (US), East Palo Alto, California, in connection with this offering.

The financial statements incorporated in this prospectus by reference from our Current Report on Form 8-K filed on October 30, 2015, have been audited by Deloitte & Touche LLP, an independent registered public accounting firm, as stated in their report, which is incorporated herein by reference. Such financial statements have been so incorporated in reliance upon the report of such firm given upon their authority as experts in accounting and auditing.

This prospectus is part of the registration statement on Form S-3 we filed with the SEC under the Securities Act and does not contain all the information set forth in the registration statement. Whenever a reference is made in this prospectus to any of our contracts, agreements or other documents, the reference may not be complete and you should refer to the exhibits that are a part of the registration statement or the exhibits to the reports or other documents incorporated by reference into this prospectus for a copy of such contract, agreement or other document. Because we are subject to the information and reporting requirements of the Exchange Act, we file annual, quarterly and current reports, proxy statements and other information with the SEC. Our SEC filings are available to the public over the Internet at the SEC’s website at http://www.sec.gov. You may also read and copy any document we file at the SEC’s Public Reference Room at 100 F Street, N.E., Washington, D.C. 20549. Please call the SEC at 1-800-SEC-0330 for further information on the operation of the Public Reference Room.

The SEC allows us to “incorporate by reference” information from other documents that we file with it, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is considered to be part of this prospectus. Information in this prospectus supersedes information incorporated by reference that we filed with the SEC prior to the date of this prospectus, while information that we file later with the SEC will automatically update and supersede the information in this prospectus. We incorporate by reference into this prospectus and the registration statement of which this prospectus is a part the information or documents listed below that we have filed with the SEC (Commission File No. 001-36365):

We also incorporate by reference any future filings (other than current reports furnished under Item 2.02 or Item 7.01 of Form 8-K and exhibits filed on such form that are related to such items unless such Form 8-K expressly provides to the contrary) made with the SEC pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act, until we file a post-effective amendment that indicates the termination of the offering of the securities made by this prospectus and will become a part of this prospectus from the date that such documents are filed with the SEC. Information in such future filings updates and supplements the information provided in this prospectus. Any statements in any such future filings will automatically be deemed to modify and supersede any information in any document we previously filed with the SEC that is incorporated or deemed to be incorporated herein by reference to the extent that statements in the later filed document modify or replace such earlier statements.

You can request a copy of these filings, at no cost, by writing or telephoning us at the following address or telephone number:


ABOUT THIS PROSPECTUS			i
PROSPECTUS SUMMARY			1
RISK FACTORS			4
SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS			5
USE OF PROCEEDS			6
DILUTION			6
DESCRIPTION OF CAPITAL STOCK			7
PLAN OF DISTRIBUTION			10
LEGAL MATTERS			11
EXPERTS			11
WHERE YOU CAN FIND MORE INFORMATION			12
INCORPORATION BY CERTAIN INFORMATION BY REFERENCE			12


Assumed offering price per share			$	7.00
Net tangible book value per share as of September 30, 2015	$	3.59
Increase in net tangible book value per share attributable to new investors in offering	$	0.92
Pro forma net tangible book value per share after giving effect to the offering	$	4.51
Dilution per share to new investors			$	2.49