Sierra Oncology (SRRA) S-3 Shelf registration

As filed with the Securities and Exchange Commission on August 1, 2016

Registration No. 333-            

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM S-3

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

PRONAI THERAPEUTICS, INC.

(Exact name of registrant as specified in its charter)

Delaware	2834	20-0138994
(State or other jurisdiction of incorporation or organization)	(Primary Standard Industrial Classification Code Number)	(I.R.S. Employer Identification Number)

2150-885 West Georgia Street

Vancouver, British Columbia, Canada V6C 3E8

(604) 558-6536

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

Nick Glover

Chief Executive Officer

2150 – 885 West Georgia Street

Vancouver, British Columbia, Canada V6C 3E8

(604) 558-6536

(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copies to:

Stephen M. Graham, Esq. Robert A. Freedman, Esq. James D. Evans, Esq. Fenwick & West LLP 1191 Second Avenue, 10th Floor Seattle, Washington 98101 (206) 389-4510 Sukhi Jagpal Chief Financial Officer 2150 – 885 West Georgia Street Vancouver, British Columbia Canada V6C 3E8

Approximate date of commencement of proposed sale to the public:

From time to time after the effective date of this Registration Statement.

If the only securities being registered on this form are being offered pursuant to dividend or interest reinvestment plans, please check the following box.  ¨

If any of the securities being registered on this form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box.  x

If this form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ¨

If this form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ¨

If this form is a registration statement filed pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box.  ¨

If this form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box.  ¨

Indicate by check mark whether the Registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer or a smaller reporting company. See definitions of “large accelerated filer,” “accelerated filer,” and “smaller reporting company” in Rule 12b-2 of the Exchange Act (Check one):

Large accelerated filer	¨	Accelerated filer	¨
Non-accelerated filer	x  (Do not check if a smaller reporting company)	Smaller reporting company	¨

CALCULATION OF REGISTRATION FEE

Title of each class of securities to be registered(1)	Amount to be registered(1)(2)	Proposed maximum offering price per security(3)	Proposed maximum aggregate offering price(3)	Amount of registration fee(4)
Common stock, $0.001 par value per share
Preferred stock, $0.001 par value per share
Debt securities
Warrants
Subscription rights
Units
Total			$150,000,000	$15,105

(1) There is being registered hereunder an indeterminate number of shares of (a) common stock, (b) preferred stock, (c) debt securities, (d) warrants to purchase common stock, preferred stock or debt securities of the Registrant, (e) subscription rights to purchase common stock, preferred stock or debt securities of the Registrant, and (f) units, consisting of some or all of these securities in any combination, as may be sold from time to time by the Registrant. Any securities registered hereunder may be sold separately or as units with other securities registered hereunder. There are also being registered hereunder an indeterminate number of shares of common stock, preferred stock and debt securities as shall be issuable upon conversion, exchange or exercise of any securities that provide for such issuance. In no event will the aggregate offering price of all types of securities issued by the Registrant pursuant to this Registration Statement exceed $150,000,000.

(2) Pursuant to Rule 416(a), this registration statement also covers any additional securities that may be offered or issued in connection with any stock split, stock dividend or similar transaction.

(3) The proposed maximum offering price per security and proposed maximum aggregate offering price per class of securities will be determined from time to time by the Registrant in connection with the issuance by the Registrant of the securities registered under this registration statement and is not specified as to each class of security pursuant to General Instruction II.D to Form S-3 under the Securities Act of 1933, as amended.

(4) Calculated pursuant to Rule 457(o) under the Securities Act of 1933, as amended.

The Registrant hereby amends this Registration Statement on such date or dates as may be necessary to delay its effective date until the Registrant shall file a further amendment which specifically states that this Registration Statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933, as amended, or until the Registration Statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to said Section 8(a), may determine.

The information in this prospectus is not complete and may be changed. We may not sell these securities until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus is not an offer to sell these securities and it is not soliciting an offer to buy these securities in any state where the offer or sale is not permitted.

SUBJECT TO COMPLETION, DATED AUGUST 1, 2016

PROSPECTUS

$150,000,000

Common Stock, Preferred Stock,

Debt Securities, Warrants, Subscription Rights and Units

From time to time, we or selling security holders may offer our common stock or preferred stock, debt securities, warrants to purchase our common stock, preferred stock or debt securities, subscription rights to purchase our common stock, preferred stock or debt securities and/or units consisting of some or all of these securities, in any combination, together or separately, in one or more offerings, in amounts, at prices and on the terms that we will determine at the time of the offering and which will be set forth in a prospectus supplement and any related free writing prospectus. The applicable prospectus supplement and any related free writing prospectus may also add, update or change information contained in this prospectus. The total amount of these securities will have an initial aggregate offering price of up to $150,000,000.

You should read this prospectus, the information incorporated, or deemed to be incorporated, by reference in this prospectus, and any applicable prospectus supplement and related free writing prospectus carefully before you invest.

Our common stock is listed on The NASDAQ Global Market under the symbol “DNAI.” The last reported sale price of our common stock on The NASDAQ Global Market on July 29, 2016 was $1.97 per share. None of the other securities we may offer are currently traded on any securities exchange. The applicable prospectus supplement and any related free writing prospectus will contain information, where applicable, as to any other listing on The NASDAQ Global Market or any securities market or exchange of the securities covered by the applicable prospectus supplement and any related free writing prospectus.

Investing in our securities involves a high degree of risk. You should review carefully the risks and uncertainties described under the heading “Risk Factors” beginning on page 4 of this prospectus and in the applicable prospectus supplement and any related free writing prospectus, and under similar headings in the documents incorporated by reference into this prospectus.

The securities may be sold by us or selling security holders to or through underwriters or dealers, directly to purchasers or through agents designated from time to time, on a continuous or delayed basis. For additional information on the methods of sale, you should refer to the discussion under the heading “Plan of Distribution” in this prospectus. If any underwriters, dealers or agents are involved in the sale of any securities with respect to which this prospectus is being delivered, the names of such underwriters or agents and any applicable fees, discounts or commissions, details regarding over-allotment options, if any, and the net proceeds to us will be set forth in a prospectus supplement. The price to the public of such securities and the net proceeds we expect to receive from such sale will also be set forth in a prospectus supplement.

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.

The date of this prospectus is                     , 2016.

TABLE OF CONTENTS

Prospectus

	Page
About this Prospectus		1
Summary		2
Risk Factors		4
Special Note Regarding Forward-Looking Statements		4
Use of Proceeds		5
Plan of Distribution		6
Description of Capital Stock		8
Description of Debt Securities		13
Description of Warrants		20
Description of Subscription Rights		23
Description of Units		23
Canadian Securities Exemption		24
Legal Matters		25
Experts		25
Where You Can Find Additional Information		25
Incorporation of Certain Information by Reference		25

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ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement that we filed with the Securities and Exchange Commission, or the SEC, using a “shelf” registration process. Under this shelf registration process, from time to time, we may sell any combination of the securities described in this prospectus in one or more offerings, up to an aggregate dollar amount of $150,000,000. We have provided to you in this prospectus a general description of the securities we may offer. Each time we sell securities under this shelf registration process, we will provide a prospectus supplement that will contain specific information about the terms of the offering. We may also add, update or change in the applicable prospectus supplement any of the information contained in this prospectus. To the extent there is a conflict between the information contained in this prospectus and the applicable prospectus supplement, you should rely on the information in the applicable prospectus supplement; provided that, 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 or any applicable prospectus supplement), the statement in the document having the later date modifies or supersedes the earlier statement. You should read both this prospectus and any applicable prospectus supplement together with additional information described under the heading “Where You Can Find Additional Information.”

You should rely only on the information contained in or incorporated by reference into this prospectus or any applicable prospectus supplement. No dealer, salesperson or any other person is authorized to give any information or to make any representation other than the information and representations contained in or incorporated by reference into this prospectus or any applicable prospectus supplement. If different information is given or different representations are made, you may not rely on that information or those representations as having been authorized by us. You may not imply from the delivery of this prospectus and any applicable prospectus supplement, nor from a sale made under this prospectus and any applicable prospectus supplement, that our affairs are unchanged since the date of this prospectus and any applicable prospectus supplement or that the information contained in any document incorporated by reference is accurate as of any date other than the date of the document incorporated by reference, regardless of the time of delivery of this prospectus and any applicable prospectus supplement or any sale of a security. This prospectus and any applicable prospectus supplement may only be used where it is legal to sell the securities.

THIS PROSPECTUS MAY NOT BE USED TO OFFER AND SELL SECURITIES UNLESS IT IS ACCOMPANIED BY A PROSPECTUS SUPPLEMENT.

Unless the context indicates otherwise, as used in this prospectus, the terms “Company,” “ProNAi,” “Registrant,” “we,” “us,” and “our” refer to ProNAi Therapeutics, Inc., a Delaware corporation, and its subsidiaries taken as a whole, unless otherwise noted.

“ProNAi” is our registered trademark. The “ProNAi” logo and all product names are our common law trademarks. This prospectus and the information incorporated herein by reference may include additional trade names, trademarks and service marks of other companies, which are the property of their respective owners. We do not intend our use or display of other companies’ trade names, trademarks or service marks to imply a relationship with, or endorsement or sponsorship of us by, these other companies.

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SUMMARY

This summary highlights information contained in other parts of this prospectus or incorporated by reference in this prospectus from our Annual Report on Form 10-K for the year ended December 31, 2015, and our other filings with the Securities and Exchange Commission listed in the section of the prospectus entitled “Incorporation of Certain Information by Reference.” This summary does not contain all of the information you should consider in making your investment decision. Before deciding to invest in our securities, you should read the entire prospectus, the applicable prospectus supplement and any related free writing prospectus, and the information incorporated by reference herein in their entirety. You should carefully consider, among other things, the matters discussed in the section entitled “Risk Factors” contained in the applicable prospectus supplement and any related free writing prospectus, and under similar headings in the other documents that are incorporated by reference into this prospectus. Some of the statements in this prospectus constitute forward-looking statements that involve risks and uncertainties. See “Special Note Regarding Forward-Looking Statements.”

Our Company

ProNAi Therapeutics, Inc. is a drug development company focused on advancing targeted therapeutics for the treatment of patients with cancer. We are managed by a world-class team with a proven track record of success in oncology drug development. We intend to build and advance a broad and diverse pipeline of promising oncology assets against emerging targets on the leading edge of cancer biology.

Our portfolio includes PNT141, a potent, selective and orally bioavailable small molecule inhibitor of the Cdc7 kinase that we recently licensed from Carna Biosciences, Inc. This kinase is a key regulator of both DNA replication and DNA damage response, making it a compelling emerging target for the potential treatment of a broad range of tumor types.

The Securities We May Offer

With this prospectus, we may offer common stock, preferred stock, debt securities, warrants to purchase our common stock, preferred stock or debt securities, subscription rights to purchase our common stock, preferred stock or debt securities, and/or units consisting of some or all of these securities in any combination. The aggregate offering price of securities that we offer with this prospectus will not exceed $150,000,000. Each time we offer securities with this prospectus, we will provide offerees with a prospectus supplement that will contain the specific terms of the securities being offered. The following is a summary of the securities we may offer with this prospectus.

Common Stock

We may offer shares of our common stock, par value $0.001 per share.

Preferred Stock

We may offer shares of our preferred stock, par value $0.001 per share, in one or more series. Our board of directors or a committee designated by our board of directors will determine the rights, preferences and privileges of the series of shares of preferred stock being offered. The rights, preferences and privileges of each series of preferred stock will be more fully described in the applicable prospectus supplement.

Debt Securities

We may offer general obligations, which may be secured or unsecured, senior or subordinated and convertible into shares of our common stock or preferred stock. In this prospectus, we refer to the all debt securities together as the “debt securities.” Our board of directors or a committee designated by our board of directors will determine the terms of each series of debt securities being offered.

We will issue the debt securities under an indenture between us and a trustee. In this document, we have summarized general features of the debt securities from the indenture. We encourage you to read the indenture, which is an exhibit to the registration statement of which this prospectus is a part.

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Warrants

We may offer warrants to purchase our common stock, preferred stock or debt securities. We may issue warrants independently or together with other securities. Our board of directors or a committee designated by our board of directors will determine the terms of the warrants.

Subscription Rights

We may offer subscription rights to purchase our common stock, preferred stock or debt securities. We may issue subscription rights independently or together with other securities. Our board of directors or a committee designated by our board of directors will determine the terms of the subscription rights.

Units

We may offer units consisting of some or all of the securities described above, in any combination, including common stock, preferred stock, warrants and/or debt securities. The terms of these units will be set forth in a prospectus supplement. The description of the terms of these units in the related prospectus supplement will not necessarily be complete. You should refer to the applicable form of unit and unit agreement for complete information with respect to these units.

Ratio of Earnings to Fixed Charges and Combined Fixed Charges and Preferred Stock Dividends

The financial information provided in the table below should be read in conjunction with our financial statements and the related notes incorporated by reference into this prospectus. The following table shows our ratio of earnings to fixed charges and the ratio of our earnings to combined fixed charges and preferred stock dividends for the periods indicated. Our net losses were inadequate to cover the fixed charges and combined fixed charges and preferred stock dividends for each of the periods presented. Because of these deficiencies, the ratio information is not applicable for the periods presented. For purposes of calculating these deficiencies, earnings consist of loss from continuing operations before income taxes and fixed charges. Fixed charges consist of interest expense and the portion of rent expense which we believe is representative of the interest component of rental expense. This table is qualified by the more detailed information appearing in the computation table set forth in Exhibit 12.1 to the registration statement of which this prospectus is a part.

	Year Ended December 31,									Three Months Ended March 31,
	2013			2014			2015			2016
(in thousands)
Ratio of earnings to fixed charges		N/A			N/A			N/A			N/A
Ratio of earnings to combined fixed charges and preferred stock dividends		N/A			N/A			N/A			N/A
Deficiency of earnings to fixed charges	$	(6,832	)	$	(23,871	)	$	(53,205	)	$	(10,530	)
Deficiency of earnings to fixed charges and preferred stock dividends(1)	$	(6,832	)	$	(23,871	)	$	(79,114	)		N/A

(1) Represents deficiency of earnings to fixed charges and preferred stock dividends during the periods in which our redeemable convertible preferred stock with dividend rights was outstanding. In connection with our initial public offering in July 2015, we paid $5.5 million to the holders of our Series B and B-1 redeemable convertible preferred stock in settlement of the cumulative dividends and issued 750,946 shares of common stock with an aggregate fair value of $20.4 million to the holders of our Series C and D redeemable convertible preferred stock in settlement of the cumulative dividends. All shares of redeemable convertible preferred stock were converted to common stock upon the closing of our initial public offering and are no longer outstanding. As of March 31, 2016, we had no shares of preferred stock outstanding, and we are not required to pay dividends on any shares of our outstanding capital stock.

Corporate Information

We were incorporated in the State of Delaware in May 2003 as Phenome Systems, Inc. and changed our name to ProNAi Therapeutics, Inc. in April 2004. Shortly thereafter, we merged with SenseGene Therapeutics Inc., a Michigan corporation, with ProNAi Therapeutics, Inc. being the surviving corporation. Our principal executive offices are located at 2150 – 885 West Georgia Street, Vancouver, British Columbia, Canada V6C 3E8, and our telephone number is (604) 558-6536. Our website address is www.pronai.com. Information contained on, or that can be accessed through, our website is not a part of this prospectus, and you should not rely on any such information in deciding whether to purchase our securities.

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RISK FACTORS

An investment in our securities involves a high degree of risk. The prospectus supplement applicable to each offering of securities will contain a discussion of the risks applicable to an investment in our securities. Prior to making a decision about investing in our securities, you should carefully consider the specific factors discussed under the heading “Risk Factors” in the applicable prospectus supplement and any free writing prospectus, together with all of the other information contained or incorporated by reference in the applicable prospectus supplement or appearing or incorporated by reference in this prospectus. You should also consider the risks, uncertainties and assumptions discussed under Part I, Item 1A, “Risk Factors,” in our Annual Report on Form 10-K for the year ended December 31, 2015, which is incorporated herein by reference, and may be amended, supplemented or superseded from time to time by other reports we file with the Securities and Exchange Commission, or SEC, in the future. The risks and uncertainties we have described are not the only ones we face. Additional risks and uncertainties not presently known to us or that we currently deem immaterial may also affect our operations.

SPECIAL NOTE REGARDINGFORWARD-LOOKING STATEMENTS

This prospectus and the documents incorporated by reference herein containforward-looking statements. All statements contained in this prospectus and the documents incorporated by reference herein other than statements of historical fact, including statements regarding our future consolidated results of operations and financial position, our business strategy and plans, market growth, and our objectives for future operations, areforward-looking statements. The words “believe,” “may,” “will,” “estimate,” “potentially,” “continue,” “anticipate,” “intend,” “expect,” “could,” “would,” “project,” “plan” and similar expressions that convey uncertainty of future events or outcomes are intended to identifyforward-looking statements. We have based theseforward-looking statements largely on our current expectations and projections about future events and trends that we believe may affect our consolidated financial condition, consolidated results of operations, business strategy,short-term andlong-term business operations and objectives and financial needs. Theseforward-looking statements are subject to a number of risks, uncertainties and assumptions, including those described under the heading “Risk Factors” in our Annual Report on Form 10-K for the year ended December 31, 2015, as well as those discussed in this prospectus, the documents incorporated by reference in this prospectus, the applicable prospectus supplement and any free writing prospectus. All subsequent written or oral forward-looking statements attributable to us or any person acting on our behalf are expressly qualified in their entirety by the cautionary statements contained or referred to in this section.

Moreover, we operate in a very competitive and rapidly changing environment. New risks emerge from time to time. It is not possible for our management to predict all risks, nor can we assess the impact of all factors on our business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in anyforward-looking statements we may make. In light of these risks, uncertainties and assumptions, the forward-looking events, circumstances and trends discussed in this prospectus and the documents incorporated by reference herein may not occur and actual results could differ materially and adversely from those anticipated or implied in theforward-looking statements.

You should not rely uponforward-looking statements as predictions of future events. The events and circumstances reflected in theforward-looking statements may not be achieved or occur. Although we believe that the expectations reflected in theforward-looking statements are reasonable, we cannot guarantee that the future results, levels of activity, performance or events and circumstances discussed in this prospectus and the documents incorporated by reference herein will be achieved or occur. We undertake no obligation to update any of theseforward-looking statements for any reason after the date of this prospectus, or in the case of documents referred to or incorporated by reference, the date of those documents, or to conform such statements to actual results or revised expectations. If we do update one or more forward-looking statements, no inference should be drawn that we will make additional updates with respect to those or other forward-looking statements.

You should read this prospectus, the documents incorporated by reference herein, the applicable prospectus supplement and any free writing prospectus, and the documents that we have filed with the SEC as exhibits to the registration statement of which this prospectus is a part with the understanding that our actual future results, levels of activity, performance and events and circumstances may be materially different from what we expect.

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USE OF PROCEEDS

We will have broad discretion over the use of the net proceeds to us from the sale of our securities under this prospectus and investors will be relying on the judgment of our management regarding the application of the proceeds. Unless otherwise provided in the applicable prospectus supplement, we intend to use the net proceeds from the sale of securities under this prospectus to fund research and development of our current and future product candidates, working capital, capital expenditures and other general corporate purposes. Additionally, we may use a portion of the net proceeds to us from the sale of our securities under this prospectus to expand our business by in-licensing or acquiring, as the case may be, commercial products, product candidates, technologies, compounds, other assets or complementary businesses. We will set forth in the applicable prospectus supplement our intended uses for the net proceeds received from the sale of any securities. Pending these uses, we intend to invest the net proceeds in investment-grade, interest-bearing securities such as money market funds, certificates of deposit, commercial paper, repurchase agreements, corporate debt and guaranteed obligations of the U.S. government.

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PLAN OF DISTRIBUTION

We may sell the securities covered by this prospectus to one or more underwriters for public offering and sale by them, and may also sell the securities to investors directly or through agents. We will name any underwriter or agent involved in the offer and sale of securities in the applicable prospectus supplement. We have reserved the right to sell or exchange securities directly to investors on our own behalf in jurisdictions where we are authorized to do so. We may distribute the securities from time to time in one or more transactions at:

• a fixed price or prices, which may be changed from time to time;

• market prices prevailing at the time of sale;

• prices related to such prevailing market prices; or

• negotiated prices.

We may directly solicit offers to purchase the securities being offered by this prospectus. We may also designate agents to solicit offers to purchase the securities from time to time. We will name in any prospectus supplement any agent involved in the offer or sale of our securities. Unless otherwise indicated in a prospectus supplement, an agent will be acting on a best efforts basis, and a dealer will purchase securities as a principal for resale at varying prices to be determined by the dealer.

If we utilize an underwriter in the sale of the securities being offered by this prospectus, we will execute an underwriting agreement with the underwriter at the time of sale and we will provide the name of any underwriter in the applicable prospectus supplement that the underwriter will use to make resales of the securities to the public. In connection with the sale of the securities, we, or the purchasers of securities for whom the underwriter may act as agent, may compensate the underwriter in the form of underwriting discounts or commissions. The underwriter may sell the securities to or through dealers, and those dealers may receive compensation in the form of discounts, concessions or commissions from the underwriters or commissions from the purchasers for whom they may act as agent.

We will provide in the applicable prospectus supplement any compensation we pay to underwriters, dealers or agents in connection with the offering of the securities, and any discounts, concessions or commissions allowed by underwriters to participating dealers. Underwriters, dealers and agents participating in the distribution of the securities may be deemed to be underwriters within the meaning of the Securities Act of 1933, as amended, or the Securities Act, and any discounts and commissions received by them and any profit realized by them on resale of the securities may be deemed to be underwriting discounts and commissions. We may enter into agreements to indemnify underwriters, dealers and agents against civil liabilities, including liabilities under the Securities Act, and to reimburse them for certain expenses. We may grant underwriters who participate in the distribution of our securities under this prospectus an option to purchase additional securities to cover any over-allotments in connection with the distribution.

The securities we offer under this prospectus may or may not be listed through The NASDAQ Global Market or any other securities exchange. To facilitate the offering of securities, certain persons participating in the offering may engage in transactions that stabilize, maintain or otherwise affect the price of the securities. This may include short sales of the securities, which involves the sale by persons participating in the offering of more securities than we sold to them. In these circumstances, these persons would cover such short positions by making purchases in the open market or by exercising their option to purchase additional securities. In addition, these persons may stabilize or maintain the price of the securities by bidding for or purchasing securities in the open market or by imposing penalty bids, whereby selling concessions allowed to dealers participating in the offering may be reclaimed if securities sold by them are repurchased in connection with stabilization transactions. The effect of these transactions may be to stabilize or maintain the market price of the securities at a level above that which might otherwise prevail in the open market. These transactions may be discontinued at any time.

We may engage in “at-the-market” offerings into an existing trading market in accordance with Rule 415(a)(4) under the Securities Act. In addition, we may enter into derivative transactions with third parties, or sell securities not covered by this prospectus to third parties in privately negotiated transactions. If the applicable prospectus supplement indicates, in connection with those derivatives, the third parties may sell securities covered by this prospectus and the applicable prospectus supplement, including short sale transactions. If so, the third party may use securities pledged by us or borrowed from us or others to settle those sales or to close out any related open borrowings of stock, and they may use securities received from us in settlement of those derivatives to close out any related open borrowings of stock. The third party in these sale transactions will be an underwriter and will be identified in the applicable prospectus supplement. In addition, we may otherwise loan or pledge

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securities to a financial institution or other third party that in turn may sell the securities short using this prospectus. The financial institution or other third party may transfer its economic short position to investors in our securities or in connection with a concurrent offering of other securities.

We will file a prospectus supplement to describe the terms of any offering of our securities covered by this prospectus. The applicable prospectus supplement will disclose:

• the terms of the offer;

• the name or names of any underwriters, including any managing underwriters, as well as any dealers or agents, and the amounts of securities underwritten or purchased by each of them;

• the purchase price of the securities from us;

• the net proceeds to us from the sale of the securities;

• any delayed delivery arrangements;

• the nature of the underwriters’ obligations to take the securities;

• any over-allotment or other options under which underwriters, if any, may purchase additional securities from us;

• any underwriting discounts, commissions or other items constituting underwriters’ compensation, and any commissions paid to agents;

• in a subscription rights offering, whether we have engaged dealer-managers to facilitate the offering or subscription, including their name or names and compensation;

• any securities exchanges or markets on which such securities may be listed;

• any public offering price; and

• other facts material to the transaction.

We will bear all or substantially all of the costs, expenses and fees in connection with the registration of our securities under this prospectus. The underwriters, dealers and agents may engage in transactions with us, or perform services for us, in the ordinary course of business.

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DESCRIPTION OF CAPITAL STOCK

General

Our authorized capital stock consists of 500,000,000 shares of common stock, $0.001 par value per share, and 10,000,000 shares of undesignated preferred stock, $0.001 par value per share. The following description summarizes the most important terms of our capital stock. Because it is only a summary, it does not contain all the information that may be important to you. For a complete description, you should refer to our restated certificate of incorporation and restated bylaws, which are included as exhibits to the registration statement of which this prospectus is a part, and to the applicable provisions of Delaware law.

As of March 31, 2016, there were 30,174,778 shares of our common stock outstanding, and no shares of preferred stock outstanding.

Common Stock

Dividend Rights

Subject to preferences that may apply to any shares of preferred stock outstanding at the time, the holders of our common stock are entitled to receive dividends out of funds legally available if our board of directors, in its discretion, determines to issue dividends and then only at the times and in the amounts that our board of directors may determine. For more information about our dividend policy, see “Dividend Policy” in our Annual Report on Form 10-K for the year ended December 31, 2015, which is incorporated by reference in this prospectus.

Voting Rights

Holders of our common stock are entitled to one vote for each share held on all matters submitted to a vote of stockholders. We have not provided for cumulative voting for the election of directors in our restated certificate of incorporation. Accordingly, holders of a majority of the shares of our common stock are able to elect all of our directors. Our restated certificate of incorporation establishes a classified board of directors, divided into three classes with staggeredthree-year terms. Only one class of directors will be elected at each annual meeting of our stockholders, with the other classes continuing for the remainder of their respectivethree-year terms.

No Preemptive or Similar Rights

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

Right to Receive Liquidation Distributions

Upon our liquidation, dissolution orwinding-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, subject to prior satisfaction of all outstanding debt and liabilities and the preferential rights of and the payment of liquidation preferences, if any, on any outstanding shares of preferred stock.

Preferred Stock

Our board of directors is authorized, subject to limitations prescribed by Delaware law, to issue 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 their qualifications, limitations or restrictions, in each case without further vote or action by our stockholders. 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 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 or preventing a change in control of our company and might adversely affect the market price of our common stock and the voting and other rights of the holders of our common stock.

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We will incorporate by reference into the registration statement of which this prospectus is a part of, the form of any certificate of designation that describes the terms of the series of preferred stock we are offering before the issuance of the related series of preferred stock. This description of the preferred stock in the certificate of designation, any applicable prospectus supplement and any related free writing prospectus will describe, among other things, the following terms of the preferred stock:

• the number of shares in any series;

• the designation for any series by number, letter or title that shall distinguish the series from any other series of preferred stock;

• the dividend rate and whether dividends on that series of preferred stock will be cumulative, noncumulative or partially cumulative;

• the voting rights of that series of preferred stock, if any;

• the conversion provisions applicable to that series of preferred stock, if any;

• the redemption or sinking fund provisions applicable to that series of preferred stock, if any;

• the liquidation preference per share of that series of preferred stock, if any;

• the rank of that series of preferred stock relative to other series of preferred stock; and

• the terms of any other preferences or rights, if any, applicable to that series of preferred stock.

The description of preferred stock set forth above and in any description of the terms of a particular series of preferred stock in the related prospectus supplement and any related free writing prospectus will not be complete. You should refer to the applicable certificate of designation for such series of preferred stock for complete information with respect to such preferred stock. The prospectus supplement will also contain a description of material U.S. federal income tax considerations relating to that series of preferred stock.

Registration Rights

Certain of our common stock holders are entitled to certain registration rights with respect to the sale of such shares under the Securities Act. We refer to these shares as registrable securities. These rights are provided under the terms of an amended and restated investors’ rights agreement between us and the holders of these shares, which was entered into in connection with our preferred stock financings, and include demand registration rights, short-form registration rights and piggyback registration rights. In any registration made pursuant to such amended and restated investors’ rights agreement, all fees, costs and expenses of underwritten registrations, including fees and disbursements of one special counsel to the selling stockholders not to exceed $30,000, will be borne by us and all selling expenses, including estimated underwriting discounts and selling commissions, will be borne by the holders of the shares being registered.

The registration rights terminate on July 21, 2020 or, with respect to any particular stockholder, at such time as such stockholder can sell all of its shares in a single transaction pursuant to Rule 144 promulgated under the Securities Act.

Demand Registration Rights

Under the terms of the amended and restated investor rights agreement, if we receive a written request from the holders of at least 25% of the registrable securities then outstanding that we file a registration statement under the Securities Act with an anticipated aggregate price to the public of at least $5.0 million, we will be obligated to notify all holders of registrable securities of the written request and use commercially reasonable efforts to effect the registration of all registrable securities that holders request to be registered. We are required to effect no more than two registration statements that are declared or ordered effective, subject to certain exceptions. We may postpone the filing of a registration statement for up to 90 days once in a 12-month period if in the good-faith judgment of our board of directors such registration would be detrimental to us.

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Piggyback Registration Rights

If we register any of our securities for public sale in an offering pursuant to this prospectus, we are required to afford each holder of registrable securities an opportunity to include all or part of the holder’s registrable securities in such registration. Each holder desiring to include all or any part of the registrable securities held by it in any such registration statement is required to notify us within 10 business days of being notified by us in writing of the registration. This right does not apply to registration statements relating to demand registrations, for Form S-3 registrations, employee benefit plans, a corporate reorganization or other transaction under Rule 145 of the Securities Act, or stock issued upon conversion of debt securities. The underwriter of any underwritten offering will have the right to limit, due to marketing factors, the number of shares registered by these holders to 30% of the total shares covered by the registration statement. In no event will shares of any other selling stockholder be included in such registration that would reduce the number of shares which may be included by these holders without the consent of the holders of at least two-thirds (66 2/3%) of the registrable securities proposed to be sold in the offering.

Form S-3 Registration Rights

The holders of registrable securities can request that we register all or a portion of their shares on Form S-3 if we are eligible to file a registration statement on Form S-3 and the aggregate price to the public of the shares offered is at least $5.0 million. The holders of registrable securities may require us to effect at most two registration statements onForm S-3 in any12-month period. We may postpone the filing of a registration statement for up to 90 days once in a 12-month period if in the good-faith judgment of our board of directors such registration would be detrimental to us or if we notify holders within 30 days of making the Form S-3 registration request that we intend to make a public offering within 90 days.

Anti-Takeover Provisions

The provisions of Delaware law, our restated certificate of incorporation and our restated bylaws could have the effect of delaying, deferring or discouraging another person from acquiring control of our company. These provisions, which are summarized below, may have the effect of discouraging takeover bids. They are also designed, in part, to encourage persons seeking to acquire control of us to negotiate first with our board of directors. We believe that the benefits of increased protection of our potential ability to negotiate with an unfriendly or unsolicited acquirer outweigh the disadvantages of discouraging a proposal to acquire us because negotiation of these proposals could result in an improvement of their terms.

Delaware Law

We are subject to the provisions of Section 203 of the Delaware General Corporation Law, or DGCL, regulating corporate takeovers. In general, DGCL Section 203 prohibits apublicly-held Delaware corporation from engaging in a business combination with an interested stockholder for a period of three years following the date on which the person became an interested stockholder unless:

• prior to the date of the transaction, the board of directors of the corporation approved either the business combination or the transaction which resulted in the stockholder becoming an interested stockholder;

• the interested stockholder owned at least 85% of the voting stock of the corporation outstanding at the time the transaction commenced, excluding for purposes of determining the voting stock outstanding, but not the outstanding voting stock owned by the interested stockholder, (1) shares owned by persons who are directors and also officers and (2) shares owned by employee stock plans in which employee participants do not have the right to determine confidentially whether shares held subject to the plan will be tendered in a tender or exchange offer; or

• at or subsequent to the date of the transaction, the business combination is approved by the board of directors of the corporation and authorized at an annual or special meeting of stockholders, and not by written consent, by the affirmative vote of at least 66 2/3% of the outstanding voting stock that is not owned by the interested stockholder.

Generally, a business combination includes a merger, asset or stock sale, or other transaction or series of transactions together resulting in a financial benefit to the interested stockholder. An interested stockholder is a person who, together with affiliates and associates, owns or, within three years prior to the determination of interested stockholder status, did own 15% or more of a corporation’s outstanding voting stock. We expect the existence of this provision to have an

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anti-takeover effect with respect to transactions our board of directors does not approve in advance. We also anticipate that DGCL Section 203 may also discourage attempts that might result in a premium over the market price for the shares of common stock held by stockholders.

Restated Certificate of Incorporation and Restated Bylaws Provisions

Our restated certificate of incorporation and our restated bylaws include a number of provisions that could deter hostile takeovers or delay or prevent changes in control of our company, including the following:

• Board of Directors Vacancies.Our restated certificate of incorporation and restated bylaws authorize only our board of directors to fill vacant directorships, including newly created seats. In addition, the number of directors constituting our board of directors is permitted to be set only by a resolution adopted by a majority vote of our entire board of directors. These provisions would prevent a stockholder from increasing the size of our board of directors and then gaining control of our board of directors by filling the resulting vacancies with its own nominees. This makes it more difficult to change the composition of our board of directors but promotes continuity of management.

• Classified Board.Our restated certificate of incorporation and restated bylaws provide that our board of directors is classified into three classes of directors, each with staggeredthree-year terms. A third party may be discouraged from making a tender offer or otherwise attempting to obtain control of us as it is more difficult and time consuming for stockholders to replace a majority of the directors on a classified board of directors.

• Stockholder Action; Special Meetings of Stockholders.Our restated certificate of incorporation provides that our stockholders may not take action by written consent, but may only take action at annual or special meetings of our stockholders. As a result, a holder controlling a majority of our capital stock would not be able to amend our restated bylaws or remove directors without holding a meeting of our stockholders called in accordance with our restated bylaws. Further, our restated bylaws and restated certificate of incorporation provide that special meetings of our stockholders may be called only by a majority of our board of directors, the chairman of our board of directors, our Chief Executive Officer or our President, thus prohibiting a stockholder from calling a special meeting. These provisions might delay the ability of our stockholders to force consideration of a proposal or for stockholders controlling a majority of our capital stock to take any action, including the removal of directors.

• Advance Notice Requirements for Stockholder Proposals and Director Nominations.Our restated bylaws provide advance notice procedures for stockholders seeking to bring business before our annual meeting of stockholders or to nominate candidates for election as directors at our annual meeting of stockholders. Our restated bylaws also specify certain requirements regarding the form and content of a stockholder’s notice. These provisions might preclude our stockholders from bringing matters before our annual meeting of stockholders or from making nominations for directors at our annual meeting of stockholders if the proper procedures are not followed. We expect that these provisions might also discourage or deter a potential acquirer from conducting a solicitation of proxies to elect the acquirer’s own slate of directors or otherwise attempting to obtain control of our company.

• No Cumulative Voting.The DGCL provides that stockholders are not entitled to the right to cumulate votes in the election of directors unless a corporation’s certificate of incorporation provides otherwise. Our restated certificate of incorporation and restated bylaws do not provide for cumulative voting.

• Directors Removed Only for Cause.Our restated certificate of incorporation provides that stockholders may remove directors only for cause and only by the affirmative vote of the holders of at least two-thirds of our outstanding common stock .

• Amendment of Charter Provisions.Any amendment of the above provisions in our restated certificate of incorporation requires approval by holders of at leasttwo-thirds of our outstanding common stock.

• Issuance of Undesignated Preferred Stock.Our board of directors has the authority, without further action by the stockholders, to issue up to 10,000,000 shares of undesignated preferred stock with rights and preferences, including voting rights, designated from time to time by our board of directors. The existence of authorized but unissued shares of preferred stock would enable our board of directors to render more difficult or to discourage an attempt to obtain control of us by means of a merger, tender offer, proxy contest or other means.

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• Choice of Forum.Our restated certificate of incorporation provides that the Court of Chancery of the State of Delaware will be the exclusive forum for: any derivative action or proceeding brought on our behalf; any action asserting a breach of fiduciary duty, any action asserting a claim against us arising pursuant to the DGCL, restated certificate of incorporation or our restated bylaws; any action to interpret, apply, enforce or determine the validity of our restated certificate of incorporation or our restated bylaws; or any action asserting a claim against us that is governed by the internal affairs doctrine. The enforceability of similar choice of forum provisions in other companies’ certificates of incorporation has been challenged in legal proceedings, and it is possible that a court could find these types of provisions to be inapplicable or unenforceable.

Exchange Listing

Our common stock is listed on The NASDAQ Global Market under the symbol “DNAI.”

Transfer Agent and Registrar

The transfer agent and registrar for our common stock is American Stock Transfer and Trust Company, LLC. The transfer agent’s address is 6201 15th Avenue, Brooklyn, New York 11219, and its telephone number is(800) 937-5449.

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DESCRIPTION OF DEBT SECURITIES

General

We will issue the debt securities offered by this prospectus and any accompanying prospectus supplement under an indenture to be entered into between us and the trustee identified in the applicable prospectus supplement. The terms of the debt securities will include those stated in the indenture and those made part of the indenture by reference to the Trust Indenture Act of 1939, as in effect on the date of the indenture. We have filed a copy of the form of indenture as an exhibit to the registration statement, of which this prospectus is a part. The indenture will be subject to and governed by the terms of the Trust Indenture Act of 1939.

We may offer under this prospectus up to an aggregate principal amount of $150,000,000 in debt securities, or if debt securities are issued at a discount, or in a foreign currency, foreign currency units or composite currency, the principal amount as may be sold for an aggregate public offering price of up to $150,000,000. Unless otherwise specified in the applicable prospectus supplement, the debt securities will represent our direct, unsecured obligations and will rank equally with all of our other unsecured indebtedness.

We may issue the debt securities in one or more series with the same or various maturities, at par, at a premium, or at a discount. We will describe the particular terms of each series of debt securities in a prospectus supplement relating to that series, which we will file with the SEC. The applicable prospectus supplement relating to the particular series of debt securities being offered will specify the particular amounts, prices and terms of those debt securities. These terms may include:

• the title of the series;

• the aggregate principal amount, and, if a series, the total amount authorized and the total amount outstanding;

• the issue price or prices, expressed as a percentage of the aggregate principal amount of the debt securities;

• any limit on the aggregate principal amount;

• the date or dates on which principal is payable or the method for determining that date or dates;

• the interest rate or rates (which may be fixed or variable) or, if applicable, the method used to determine such rate or rates;

• the date or dates from which interest, if any, will be payable and any regular record date for the interest payable;

• the place or places where principal and, if applicable, premium and interest, is payable;

• the terms and conditions upon which we may, or the holders may require us to, redeem or repurchase the debt securities;

• the denominations in which such debt securities may be issuable, if other than denominations of $1,000 or any integral multiple of that number;

• whether the debt securities are to be issuable in the form of certificated securities (as described below) or global securities (as described below);

• the portion of principal amount that will be payable upon declaration of acceleration of the maturity date if other than the principal amount of the debt securities;

• the currency of denomination;

• the designation of the currency, currencies or currency units in which payment of principal and, if applicable, premium and interest, will be made;

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• if payments of principal and, if applicable, premium or interest, on the debt securities are to be made in one or more currencies or currency units other than the currency of denomination, the manner in which the exchange rate with respect to such payments will be determined;

• if amounts of principal and, if applicable, premium and interest may be determined by reference to an index based on a currency or currencies or by reference to a commodity, commodity index, stock exchange index or financial index, then the manner in which such amounts will be determined;

• the provisions, if any, relating to any collateral provided for such debt securities;

• any addition to or change in the covenants and/or the acceleration provisions described in this prospectus or in the indenture;

• any events of default, if not otherwise described below under “Events of Default”;

• the terms and conditions, if any, for conversion into or exchange for shares of our common stock or preferred stock;

• any depositaries, interest rate calculation agents, exchange rate calculation agents or other agents;

• the terms and conditions, if any, upon which the debt securities shall be subordinated in right of payment to our other indebtedness;

• the applicable CUSIP number; and

• any other terms specific to the debt securities.

We may issue discount debt securities that provide for an amount less than the stated principal amount to be due and payable upon acceleration of the maturity of such debt securities in accordance with the terms of the indenture. We may also issue debt securities in bearer form, with or without coupons. If we issue discount debt securities or debt securities in bearer form, we will describe material U.S. federal income tax considerations and other material special considerations which apply to these debt securities in the applicable prospectus supplement.

We may issue debt securities denominated in or payable in a foreign currency or currencies or a foreign currency unit or units. If we do, we will describe the restrictions, elections, and general tax considerations relating to the debt securities and the foreign currency or currencies or foreign currency unit or units in the applicable prospectus supplement.

Debt securities offered under this prospectus and any prospectus supplement will be subordinated in right of payment to our senior indebtedness. In addition, we will seek the consent of the holders of any such senior indebtedness prior to issuing any debt securities under this prospectus to the extent required by the agreements evidencing such senior indebtedness.

Registrar and Paying Agent

The debt securities may be presented for registration of transfer or for exchange at the corporate trust office of the security registrar or at any other office or agency that we maintain for those purposes. In addition, the debt securities may be presented for payment of principal, interest and any premium at the office of the paying agent or at any office or agency that we maintain for those purposes.

Conversion or Exchange Rights

Debt securities may be convertible into or exchangeable for shares of our common stock or preferred stock. The terms and conditions of conversion or exchange will be stated in the applicable prospectus supplement. The terms will include, among others, the following:

• the conversion or exchange price;

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• the conversion or exchange period;

• provisions regarding the convertibility or exchangeability of the debt securities, including who may convert or exchange;

• events requiring adjustment to the conversion or exchange price;

• provisions affecting conversion or exchange in the event of our redemption of the debt securities; and

• any anti-dilution provisions, if applicable.

Registered Global Securities

If we decide to issue debt securities in the form of one or more global securities, then we will register the global securities in the name of the depositary for the global securities or the nominee of the depositary, and the global securities will be delivered by the trustee to the depositary for credit to the accounts of the holders of beneficial interests in the debt securities.

The applicable prospectus supplement will describe the specific terms of the depositary arrangement for debt securities of a series that are issued in global form. None of us, the trustee, any payment agent or the security registrar will have any responsibility or liability for any aspect of the records relating to or payments made on account of beneficial ownership interests in a global debt security or for maintaining, supervising or reviewing any records relating to these beneficial ownership interests.

No Protection in the Event of Change of Control

The indenture does not have any covenants or other provisions providing for a put or increased interest or otherwise that would afford holders of our debt securities additional protection in the event of a recapitalization transaction, a change of control or a highly leveraged transaction. If we offer any covenants or provisions of this type with respect to any debt securities covered by this prospectus, we will describe them in the applicable prospectus supplement.

Covenants

Unless otherwise indicated in this prospectus or the applicable prospectus supplement, our debt securities will not have the benefit of any covenants that limit or restrict our business or operations, the pledging of our assets or the incurrence by us of indebtedness. We will describe in the applicable prospectus supplement any material covenants in respect of a series of debt securities.

Merger, Consolidation or Sale of Assets

The form of indenture provides that we will not consolidate with or merge into any other person or convey, transfer, sell or lease our properties and assets substantially as an entirety to any person, unless:

• we are the surviving person of such merger or consolidation, or if we are not the surviving person, the person formed by the consolidation or into or with which we are merged or the person to which our properties and assets are conveyed, transferred, sold or leased, is a corporation organized and existing under the laws of the United States, any state or the District of Columbia or a corporation or comparable legal entity organized under the laws of a foreign jurisdiction and has expressly assumed all of our obligations, including the payment of the principal of and, premium, if any, and interest on the debt securities and the performance of the other covenants under the indenture; and

• immediately before and immediately after giving effect to the transaction on a pro forma basis, no event of default, and no event which, after notice or lapse of time or both, would become an event of default, has occurred and is continuing under the indenture.

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Events of Default

Unless otherwise specified in the applicable prospectus supplement, the following events will be events of default under the indenture with respect to debt securities of any series:

• we fail to pay any principal or premium, if any, when it becomes due;

• we fail to pay any interest within 30 days after it becomes due; however, if we extend an interest payment under the terms of the debt securities, the extension will not be a failure to pay interest;

• we fail to observe or perform any other covenant in the debt securities or the indenture for 60 days after written notice specifying the failure from the trustee or the holders of not less than 25% in aggregate principal amount of the outstanding debt securities of that series;

• certain events involving bankruptcy, insolvency or reorganization of us or any of our significant subsidiaries; and

• any other event of default provided in the applicable resolution of our board of directors or the supplemental indenture under which we issue debt securities.

The trustee may withhold notice to the holders of the debt securities of any series of any default, except in payment of principal or premium, if any, or interest on the debt securities of a series, if the trustee considers it to be in the best interest of the holders of the debt securities of that series to do so.

If an event of default (other than an event of default resulting from certain events of bankruptcy, insolvency or reorganization) occurs, and is continuing, then the trustee or the holders of not less than 25% in aggregate principal amount of the outstanding debt securities of any series may accelerate the maturity of the debt securities. If this happens, the entire principal amount, plus the premium, if any, of all the outstanding debt securities of the affected series plus accrued interest to the date of acceleration will be immediately due and payable. At any time after the acceleration, but before a judgment or decree based on such acceleration is obtained by the trustee, the holders of a majority in aggregate principal amount of outstanding debt securities of such series may rescind and annul such acceleration if:

• all events of default (other than nonpayment of accelerated principal, premium or interest) have been cured or waived;

• all lawful interest on overdue interest and overdue principal has been paid; and

• the rescission would not conflict with any judgment or decree.

In addition, if the acceleration occurs at any time when we have outstanding indebtedness that is senior to the debt securities, the payment of the principal amount of outstanding debt securities may be subordinated in right of payment to the prior payment of any amounts due under the senior indebtedness, in which case the holders of debt securities will be entitled to payment under the terms prescribed in the instruments evidencing the senior indebtedness and the indenture.

If an event of default resulting from certain events of bankruptcy, insolvency or reorganization occurs, the principal, premium and interest amount with respect to all of the debt securities of any series will be due and payable immediately without any declaration or other act on the part of the trustee or the holders of the debt securities of that series.

The holders of a majority in principal amount of the outstanding debt securities of a series will have the right to waive any existing default or compliance with any provision of the indenture or the debt securities of that series and to direct the time, method and place of conducting any proceeding for any remedy available to the trustee, subject to certain limitations specified in the indenture.

No holder of any debt security of a series will have any right to institute any proceeding with respect to the indenture or for any remedy under the indenture, unless:

• the holder gives to the trustee written notice of a continuing event of default;

• the holders of at least 25% in aggregate principal amount of the outstanding debt securities of the affected series make a written request and offer reasonable indemnity to the trustee to institute a proceeding as trustee;

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• the trustee fails to institute a proceeding within 60 days after such request; and

• the holders of a majority in aggregate principal amount of the outstanding debt securities of the affected series do not give the trustee a direction inconsistent with such request during such 60-day period.

These limitations do not, however, apply to a suit instituted for payment on debt securities of any series on or after the due dates expressed in the debt securities.

We will periodically deliver certificates to the trustee regarding our compliance with our obligations under the indenture.

Modification and Waiver

From time to time, we and the trustee may, without the consent of holders of the debt securities of one or more series, amend the indenture or the debt securities of one or more series, or supplement the indenture, for certain specified purposes, including:

• to provide that the surviving entity following a change of control permitted under the indenture will assume all of our obligations under the indenture and debt securities;

• to provide for certificated debt securities in addition to uncertificated debt securities;

• to comply with any requirements of the SEC under the Trust Indenture Act of 1939;

• to provide for the issuance of and establish the form and terms and conditions of debt securities of any series as permitted by the indenture;

• to cure any ambiguity, defect or inconsistency, or make any other change that does not materially and adversely affect the rights of any holder; and

• to appoint a successor trustee under the indenture with respect to one or more series.

From time to time we and the trustee may, with the consent of holders of at least a majority in principal amount of an outstanding series of debt securities, amend or supplement the indenture or the debt securities series, or waive compliance in a particular instance by us with any provision of the indenture or the debt securities. We may not, however, without the consent of each holder affected by such action, modify or supplement the indenture or the debt securities or waive compliance with any provision of the indenture or the debt securities in order to:

• reduce the amount of debt securities whose holders must consent to an amendment, supplement, or waiver to the indenture or such debt security;

• reduce the rate of or change the time for payment of interest on any debt securities;

• reduce the principal of or change the stated maturity of any debt securities, or reduce the amount of or postpone the date for payment of sinking fund or analogous obligations;

• make any debt security payable in money other than that stated in the debt security;

• change the amount or time of any payment required or reduce the premium payable upon any redemption, or change the time before which no such redemption may be made;

• waive a default in the payment of the principal of, premium, if any, or interest on the debt securities or a redemption payment;

• waive a redemption payment with respect to any debt securities or change any provision with respect to redemption of debt securities;

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• make changes to the restrictions on a holder’s right to institute proceedings, except to increase the amount of debt securities whose holders must consent to any such matter; and

• take any other action otherwise prohibited by the indenture to be taken without the consent of each holder affected by the action.

Defeasance of Debt Securities and Certain Covenants in Certain Circumstances

The indenture permits us, at any time, to elect to discharge our obligations with respect to one or more series of debt securities by following certain procedures described in the indenture. These procedures will allow us either:

• to defease and be discharged from any and all of our obligations with respect to any debt securities except for the following obligations (which discharge is referred to as “legal defeasance”):

1. to register the transfer or exchange of such debt securities;

2. to replace temporary or mutilated, destroyed, lost or stolen debt securities;

3. to compensate and indemnify the trustee;

4. to maintain an office or agency in respect of the debt securities and to hold monies for payment in trust; or

• to be released from our obligations with respect to the debt securities under certain covenants contained in the indenture, as well as any additional covenants which may be contained in the applicable supplemental indenture (which release is referred to as “covenant defeasance”).

In order to exercise either defeasance option, we must irrevocably deposit with the trustee or other qualifying trustee, in trust for that purpose:

• money;

• U.S. Government Obligations (as described below) or Foreign Government Obligations (as described below) that through the scheduled payment of principal and interest in accordance with their terms will provide money; or

• a combination of money and/or U.S. Government Obligations and/or Foreign Government Obligations sufficient in the written opinion of a nationally-recognized firm of independent accountants to provide money;

that, in each case specified above, provides a sufficient amount to pay the principal of, premium, if any, and interest, if any, on the debt securities of the series, on the scheduled due dates or on a selected date of redemption in accordance with the terms of the indenture.

In addition, defeasance may be effected only if, among other things:

• in the case of either legal or covenant defeasance, we deliver to the trustee an opinion of counsel, as specified in the indenture, stating that as a result of the defeasance neither the trust nor the trustee will be required to register as an investment company under the Investment Company Act of 1940;

• in the case of legal defeasance, we deliver to the trustee an opinion of counsel stating that we have received from, or there has been published by, the Internal Revenue Service a ruling to the effect that, or there has been a change in any applicable federal income tax law with the effect that (and the opinion shall confirm that), the holders of outstanding debt securities will not recognize income, gain or loss for U.S. federal income tax purposes solely as a result of such legal defeasance and will be subject to U.S. federal income tax on the same amounts, in the same manner, including as a result of prepayment, and at the same times as would have been the case if legal defeasance had not occurred;

• in the case of covenant defeasance, we deliver to the trustee an opinion of counsel to the effect that the holders of the outstanding debt securities will not recognize income, gain or loss for U.S. federal income tax purposes as a result of covenant defeasance and will be subject to U.S. federal income tax on the same amounts, in the same manner and at the same times as would have been the case if covenant defeasance had not occurred; and

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• certain other conditions described in the indenture are satisfied.

If we fail to comply with our remaining obligations under the indenture and applicable supplemental indenture after a covenant defeasance of the indenture and applicable supplemental indenture, and the debt securities are declared due and payable because of the occurrence of any undefeased event of default, the amount of money and/or U.S. Government Obligations and/or Foreign Government Obligations on deposit with the trustee could be insufficient to pay amounts due under the debt securities of the affected series at the time of acceleration. We will, however, remain liable in respect of these payments.

The term “U.S. Government Obligations” as used in the above discussion means securities that are direct obligations of or non-callable obligations guaranteed by the United States of America for the payment of which obligation or guarantee the full faith and credit of the United States of America is pledged.

The term “Foreign Government Obligations” as used in the above discussion means, with respect to debt securities of any series that are denominated in a currency other than U.S. dollars, (1) direct obligations of the government that issued or caused to be issued such currency for the payment of which obligations its full faith and credit is pledged or (2) obligations of a person controlled or supervised by or acting as an agent or instrumentality of such government the timely payment of which is unconditionally guaranteed as a full faith and credit obligation by that government, which in either case under clauses (1) or (2), are not callable or redeemable at the option of the issuer.

Regarding the Trustee

We will identify the trustee with respect to any series of debt securities in the applicable prospectus supplement relating to the applicable debt securities. You should note that if the trustee becomes a creditor of ours, the indenture and the Trust Indenture Act of 1939 limit the rights of the trustee to obtain payment of claims in certain cases, or to realize on certain property received in respect of any such claim, as security or otherwise. The trustee and its affiliates may engage in, and will be permitted to continue to engage in, other transactions with us and our affiliates. If, however, the trustee acquires any “conflicting interest” within the meaning of the Trust Indenture Act of 1939, it must eliminate such conflict or resign.

The holders of a majority in principal amount of the then outstanding debt securities of any series may direct the time, method and place of conducting any proceeding for exercising any remedy available to the trustee. If an event of default occurs and is continuing, the trustee, in the exercise of its rights and powers, must use the degree of care and skill of a prudent person in the conduct of his or her own affairs. Subject to that provision, the trustee will be under no obligation to exercise any of its rights or powers under the indenture at the request of any of the holders of the debt securities, unless they have offered to the trustee reasonable indemnity or security.

No Individual Liability of Incorporators, Stockholders, Officers or Directors

Each indenture provides that no incorporator and no past, present or future stockholder, officer or director of our company or any successor corporation in those capacities will have any individual liability for any of our obligations, covenants or agreements under the debt securities or such indenture.

Governing Law

The indentures and the debt securities will be governed by, and construed in accordance with, the laws of the State of New York.

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DESCRIPTION OF WARRANTS

General

We may issue warrants for the purchase of our common stock, preferred stock, debt securities or any combination thereof. Warrants may be issued independently or together with our debt securities, preferred stock or common stock and may be attached to or separate from any offered securities. Each series of warrants will be issued under a separate warrant agreement to be entered into between us and a bank or trust company, as warrant agent. The warrant agent will act solely as our agent in connection with the warrants. The warrant agent will not have any obligation or relationship of agency or trust for or with any holders or beneficial owners of warrants. This summary of certain provisions of the warrants is not complete. For the terms of a particular series of warrants, you should refer to the applicable prospectus supplement for that series of warrants and the warrant agreement for that particular series.

Debt Warrants

The applicable prospectus supplement relating to a particular issue of warrants to purchase debt securities will describe the terms of the debt warrants, including the following:

• the title of the debt warrants;

• the offering price for the debt warrants, if any;

• the aggregate number of the debt warrants;

• the designation and terms of the debt securities, including any conversion rights, purchasable upon exercise of the debt warrants;

• if applicable, the date from and after which the debt warrants and any debt securities issued with them will be separately transferable;

• the principal amount of debt securities that may be purchased upon exercise of a debt warrant and the exercise price for the warrants, which may be payable in cash, securities or other property;

• the dates on which the right to exercise the debt warrants will commence and expire;

• if applicable, the minimum or maximum amount of the debt warrants that may be exercised at any one time;

• whether the debt warrants represented by the debt warrant certificates or debt securities that may be issued upon exercise of the debt warrants will be issued in registered or bearer form;

• information with respect to book-entry procedures, if any;

• the currency or currency units in which the offering price, if any, and the exercise price are payable;

• if applicable, a discussion of material U.S. federal income tax considerations;

• the antidilution provisions of the debt warrants, if any;

• the redemption or call provisions, if any, applicable to the debt warrants;

• any provisions with respect to the holder’s right to require us to repurchase the debt warrants upon a change in control or similar event; and

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• any additional terms of the debt warrants, including procedures and limitations relating to the exchange, exercise and settlement of the debt warrants.

Debt warrant certificates will be exchangeable for new debt warrant certificates of different denominations. Debt warrants may be exercised at the corporate trust office of the warrant agent or any other office indicated in the applicable prospectus supplement. Prior to the exercise of their debt warrants, holders of debt warrants will not have any of the rights of holders of the debt securities purchasable upon exercise and will not be entitled to payment of principal or any premium, if any, or interest on the debt securities purchasable upon exercise.

Equity Warrants

The applicable prospectus supplement relating to a particular series of warrants to purchase our common stock or preferred stock will describe the terms of the warrants, including the following:

• the title of the warrants;

• the offering price for the warrants, if any;

• the aggregate number of warrants;

• the designation and terms of the common stock or preferred stock that may be purchased upon exercise of the warrants;

• if applicable, the designation and terms of the securities with which the warrants are issued and the number of warrants issued with each security;

• if applicable, the date from and after which the warrants and any securities issued with the warrants will be separately transferable;

• the number of shares of common stock or preferred stock that may be purchased upon exercise of a warrant and the exercise price for the warrants;

• the dates on which the right to exercise the warrants shall commence and expire;

• if applicable, the minimum or maximum amount of the warrants that may be exercised at any one time;

• the currency or currency units in which the offering price, if any, and the exercise price are payable;

• if applicable, a discussion of material U.S. federal income tax considerations;

• the antidilution provisions of the warrants, if any;

• the redemption or call provisions, if any, applicable to the warrants;

• any provisions with respect to a holder’s right to require us to repurchase the warrants upon a change in control or similar event; and

• any additional terms of the warrants, including procedures and limitations relating to the exchange, exercise and settlement of the warrants.

Holders of equity warrants will not be entitled:

• to vote, consent or receive dividends;

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• receive notice as stockholders with respect to any meeting of stockholders for the election of our directors or any other matter; or

• exercise any rights as stockholders.

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DESCRIPTION OF SUBSCRIPTION RIGHTS

We may issue subscription rights to purchase our common stock, preferred stock or debt securities. These subscription rights may be offered independently or together with any other security offered hereby and may or may not be transferable by the stockholder receiving the subscription rights in such offering. In connection with any offering of subscription rights, we may enter into a standby arrangement with one or more underwriters or other purchasers pursuant to which the underwriters or other purchasers may be required to purchase any securities remaining unsubscribed for after such offering.

The applicable prospectus supplement relating to any subscription rights we offer, if any, will, to the extent applicable, include specific terms relating to the offering, including some or all of the following:

• the price, if any, for the subscription rights;

• the exercise price payable for our common stock, preferred stock or debt securities upon the exercise of the subscription rights;

• the number of subscription rights to be issued to each stockholder;

• the number and terms of our common stock, preferred stock or debt securities which may be purchased per each subscription right;

• the extent to which the subscription rights are transferable;

• any other terms of the subscription rights, including the terms, procedures and limitations relating to the exchange and exercise of the subscription rights;

• the date on which the right to exercise the subscription rights shall commence, and the date on which the subscription rights shall expire;

• the extent to which the subscription rights may include an over-subscription privilege with respect to unsubscribed securities or an over-allotment privilege to the extent the securities are fully subscribed; and

• if applicable, the material terms of any standby underwriting or purchase arrangement which may be entered into by us in connection with the offering of subscription rights.

The description in the applicable prospectus supplement of any subscription rights we offer will not necessarily be complete and will be qualified in its entirety by reference to the applicable subscription rights certificate, which will be filed with the SEC if we offer subscription rights. We urge you to read the applicable subscription rights certificate and any applicable prospectus supplement in their entirety.

DESCRIPTION OF UNITS

We may issue units consisting of some or all of the securities described above, in any combination, including common stock, preferred stock, warrants and/or debt securities. The terms of these units will be set forth in a prospectus supplement. The description of the terms of these units in the related prospectus supplement will not necessarily be complete. You should refer to the applicable form of unit and unit agreement for complete information with respect to these units.

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CANADIAN SECURITIES EXEMPTION

Pursuant to an exemption order of the British Columbia Securities Commission (BCSC) dated June 9, 2016, the BCSC has ordered that the distribution of stock by us under U.S. public offerings from time to time is exempt from the prospectus requirement of British Columbia securities laws, provided that:

(i) the distribution is not made to any resident of British Columbia, except under exemptions from the prospectus requirement available under theSecurities Act (British Columbia);

(ii) the distribution complies with U.S. securities laws and the requirements of The NASDAQ Stock Exchange;

(iii) at the distribution date:

(a) the majority of our executive officers and the majority of our directors are not residents of Canada;

(b) our principal research facilities are not located in Canada; and

(c) our securities are listed on The NASDAQ Stock Exchange and we are subject to the reporting obligations of the Securities and Exchange Commission;

(iv) at the distribution date, after giving effect to the distribution and any other distribution of securities of the same class or series that were issued at the same time as or as part of the same distribution, residents of Canada

(a) do not own, directly or indirectly, more than 10% of the outstanding securities of the class or series; and

(b) do not represent in number more than 10% of the total number of owners directly or indirectly of securities of the class or series; and

(v) in the 12 months preceding the distribution date, we have not taken any actions for the purpose of, or that could reasonably be expected to have the effect of, preparing the market or creating a demand for our shares in Canada.

If the exemption order cannot be relied upon to issue stock in U.S. public offerings, we would be required to file a prospectus with the British Columbia Securities Commission to distribute the stock in U.S. public offerings.

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LEGAL MATTERS

The validity of the securities offered by this prospectus will be passed upon for us by Fenwick & West LLP, Seattle, Washington. Additional legal matters may be passed upon for us or any underwriters, dealers or agents by counsel that we will name in the applicable prospectus supplement.

EXPERTS

The financial statements incorporated in this Prospectus by reference from the Company’s Annual Report on Form 10-K 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.

WHERE YOU CAN FIND ADDITIONAL INFORMATION

We are subject to the informational requirements of the Securities Exchange Act of 1934, as amended, or the Exchange Act, and are required to file annual, quarterly and other reports, proxy statements and other information with the SEC. You may inspect and copy these reports, proxy statements and other information at the public reference facilities maintained by the SEC in Washington, DC, 100 F Street N.E., Washington, DC 20549, and copies of all or any part of the registration statement may be obtained from that office. Please call the SEC at 1-800-SEC-0330 for further information about the public reference room. The SEC also maintains a website that contains reports, proxy and information statements and other information regarding registrants that file electronically with the SEC. The address of the website is www.sec.gov. You may also inspect the documents described herein at our principal executive offices, 2150-885 West Georgia Street, Vancouver, British Columbia, Canada V6C 3E8, during normal business hours.

Information about us is also available at our website at www.pronai.com. However, the information on our website is not a part of this prospectus and is not incorporated by reference into this prospectus.

INCORPORATION OF CERTAIN INFORMATION BY REFERENCE

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.

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 FileNo. 001-37490) or may file with the SEC under Section 13(a), 13(c), 14 or 15(d) of the Exchange Act prior to the termination of any offering of securities made by this prospectus:

• our Annual Report onForm 10-K for the year ended December 31, 2015, filed with the SEC on March 3, 2016;

• our Quarterly Report onForm 10-Q for the quarter ended March 31, 2016, filed with the SEC on May 10, 2016;

• the information specifically incorporated by reference into our Annual Report onForm 10-K for the year ended December 31, 2015 from our Definitive Proxy Statement on Schedule 14A, filed with the SEC on April 27, 2016;

• our Current Reports onForm 8-K, filed with the SEC on January 13, 2016, January 29, 2016, March 9, 2016, May 2, 2016, May 27, 2016, June 6, 2016 and June 21, 2016;

• the description of our common stock contained in our registration statement on Form 8-A filed with the SEC on July 8, 2015 under Section 12(b) of the Exchange Act, including any amendment or report filed for the purpose of updating such description; and

• filings we make with the SEC pursuant to the Exchange Act after the date of the initial registration statement, of which this prospectus is a part, and prior to the effectiveness of the registration statement.

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We will furnish without charge to you, on written or oral request, a copy of any or all of the documents incorporated by reference, including exhibits to these documents. You should direct any requests for documents to ProNAi Therapeutics, Inc., 2150-885 West Georgia Street, Vancouver, British Columbia, Canada V6C 3E8. Copies of the above reports may also be accessed from our website at pronai.investorroom.com. We do not incorporate the information from our website into this prospectus or any supplement to this prospectus and you should not consider any information on, or that can be accessed through, our website as part of this prospectus or any supplement to this prospectus (other than those filings with the SEC that we specifically incorporate by reference into this prospectus or any supplement to this prospectus). See the section of this prospectus entitled “Where You Can Find Additional Information” for information concerning how to read and obtain copies of materials that we file with the SEC at the SEC’s public offices.

Any statement contained in a document incorporated or deemed to be incorporated by reference in this prospectus, will be deemed modified, superseded or replaced for purposes of this prospectus to the extent that a statement contained in this prospectus modifies, supersedes or replaces such statement.

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$150,000,000

Common Stock

Preferred Stock

Debt Securities

Warrants

Subscription Rights

Units

PROSPECTUS

PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

Item 14. Other Expenses of Issuance and Distribution

The following table sets forth estimated expenses in connection with the issuance and distribution of the securities being registered. All amounts shown are estimates except for the SEC registration fee.

SEC registration fee	$	15,105
NASDAQ listing fee		*
Printing and engraving		*
Legal fees and expenses		*
Accounting fees and expenses		*
Transfer agent and registrar fees and expenses		*
Trustee fees and expenses		*
Miscellaneous expenses		*
Total	$	*

* These fees are calculated based on the type of securities offered and the number of issuances and accordingly, cannot be estimated at this time. An estimate of the aggregate expenses in connection with the sale and distribution of securities being offered will be included in the applicable prospectus supplement.

Item 15. Indemnification of Officers and Directors

Section 145 of the Delaware General Corporation Law authorizes a court to award, or a corporation’s board of directors to grant, indemnity to directors and officers under certain circumstances and subject to certain limitations. The terms of Section 145 of the Delaware General Corporation Law are sufficiently broad to permit indemnification under certain circumstances for liabilities, including reimbursement of expenses incurred, arising under the Securities Act of 1933, as amended.

As permitted by the Delaware General Corporation Law, the Registrant’s restated certificate of incorporation contains provisions that eliminate the personal liability of its directors for monetary damages for any breach of fiduciary duties as a director, except liability for the following:

• any breach of the director’s duty of loyalty to the Registrant or its stockholders;

• acts or omissions not in good faith or that involve intentional misconduct or a knowing violation of law;

• under Section 174 of the Delaware General Corporation Law (regarding unlawful dividends and stock purchases); or

• any transaction from which the director derived an improper personal benefit.

As permitted by the Delaware General Corporation Law, the Registrant’s restated bylaws provide that:

• the Registrant is required to indemnify its directors and executive officers to the fullest extent permitted by the Delaware General Corporation Law, subject to very limited exceptions;

• the Registrant may indemnify its other employees and agents as set forth in the Delaware General Corporation Law;

• the Registrant is required to advance expenses, as incurred, to its directors and executive officers in connection with a legal proceeding to the fullest extent permitted by the Delaware General Corporation Law, subject to very limited exceptions; and

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• the rights conferred in the restated bylaws are not exclusive.

The Registrant has entered into indemnification agreements with each of its current directors and executive officers to provide these directors and executive officers additional contractual assurances regarding the scope of the indemnification set forth in the Registrant’s restated certificate of incorporation and restated bylaws and to provide additional procedural protections. There is no pending litigation or proceeding involving a director or executive officer of the Registrant for which indemnification is sought. The indemnification provisions in the Registrant’s restated certificate of incorporation, restated bylaws and the indemnification agreements entered into between the Registrant and each of its directors and executive officers may be sufficiently broad to permit indemnification of the Registrant’s directors and executive officers for liabilities arising under the Securities Act.

The Registrant currently carries liability insurance for its directors and officers.

Item 16. Exhibits

The exhibits listed in the accompanying Exhibit Index are incorporated by reference herein and are filed (except where otherwise indicated) as part of this registration statement.

Item 17. Undertakings.

(a) The undersigned Registrant hereby undertakes:

(1) To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:

(i) To include any prospectus required by Section 10(a)(3) of the Securities Act of 1933;

(ii) To reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the SEC pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than 20 percent change in the maximum aggregate offering price set forth in the “Calculation of Registration Fee” table in the effective registration statement;

(iii) To include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration statement;

Provided, however, that paragraphs (a)(1)(i), (a)(1)(ii) and (a)(1)(iii) of this section do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the SEC by the Registrant pursuant to Section 13 or Section 15(d) of the Securities Exchange Act of 1934 that are incorporated by reference in the registration statement or is contained in a form of prospectus filed pursuant to Rule 424(b) that is part of the registration statement.

(2) That, for the purpose of determining any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(3) To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

(5) That, for the purpose of determining liability under the Securities Act of 1933 to any purchaser:

(i) Each prospectus filed by the Registrant pursuant to Rule 424(b)(3) shall be deemed to be part of the registration statement as of the date the filed prospectus was deemed part of and included in the registration statement; and

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(ii) Each prospectus required to be filed pursuant to Rule 424(b)(2), (b)(5), or (b)(7) as part of a registration statement in reliance on Rule 430B relating to an offering made pursuant to Rule 415(a)(1)(i), (vii), or (x) for the purpose of providing the information required by Section 10(a) of the Securities Act of 1933 shall be deemed to be part of and included in the registration statement as of the earlier of the date such form of prospectus is first used after effectiveness or the date of the first contract of sale of securities in the offering described in the prospectus. As provided in Rule 430B, for liability purposes of the issuer and any person that is at that date an underwriter, such date shall be deemed to be a new effective date of the registration statement relating to the securities in the registration statement to which that prospectus relates, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof. Provided, however, that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such effective date, supersede or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such effective date.

(6) That, for the purpose of determining liability of the Registrant under the Securities Act of 1933 to any purchaser in the initial distribution of the securities: The undersigned Registrant undertakes that in a primary offering of securities of the undersigned Registrant pursuant to this registration statement, regardless of the underwriting method used to sell the securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the following communications, the undersigned Registrant will be a seller to the purchaser and will be considered to offer or sell such securities to such purchaser:

(i) Any preliminary prospectus or prospectus of the undersigned Registrant relating to the offering required to be filed pursuant to Rule 424;

(ii) Any free writing prospectus relating to the offering prepared by or on behalf of the undersigned Registrant or used or referred to by the undersigned registrant;

(iii) The portion of any other free writing prospectus relating to the offering containing material information about the undersigned Registrant or its securities provided by or on behalf of the undersigned registrant; and

(iv) Any other communication that is an offer in the offering made by the undersigned Registrant to the purchaser.

(b) The undersigned Registrant hereby undertakes that, for purposes of determining any liability under the Securities Act of 1933, each filing of the registrant’s annual report pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing of an employee benefit plan’s annual report pursuant to Section 15(d) of the Securities Exchange Act of 1934) that is incorporated by reference in the registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(e) The undersigned registrant hereby undertakes to deliver or cause to be delivered with the prospectus, to each person to whom the prospectus is sent or given, the latest annual report, to security holders that is incorporated by reference in the prospectus and furnished pursuant to and meeting the requirements of Rule 14a-3 or Rule 14c-3 under the Securities Exchange Act of 1934; and, where interim financial information required to be presented by Article 3 of Regulation S-X is not set forth in the prospectus, to deliver, or cause to be delivered to each person to whom the prospectus is sent or given, the latest quarterly report that is specifically incorporated by reference in the prospectus to provide such interim financial information.

(h) Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the Registrant pursuant to the foregoing provisions, or otherwise, the Registrant has been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the Registrant of expenses incurred or paid by a director, officer or controlling person of the Registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the Registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act and will be governed by the final adjudication of such issue.

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(j) If and when applicable, the Registrant hereby undertakes to file an application for the purpose of determining the eligibility of the trustee to act under subsection (a) of section 310 of the Trust Indenture Act in accordance with the rules and regulations prescribed by the Securities and Exchange Commission under section 305(b)(2) of the Act.

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SIGNATURES

Pursuant to the requirements of the Securities Act, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this Registration Statement on Form S-3 to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Vancouver, Province of British Columbia, on this 1st day of August 2016.

	PRONAI THERAPEUTICS, INC.
By:	/s/ Nick Glover
	Dr. Nick Glover President and Chief Executive Officer

KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below hereby constitutes and appoints Dr. Nick Glover and Sukhi Jagpal, and each of them, as his or her true and lawful attorneys-in-fact, proxies and agents, each with full power of substitution, for him or her in any and all capacities, to sign any and all amendments to this registration statement (including post-effective amendments or any abbreviated registration statement and any amendments thereto filed pursuant to Rule 462(b) increasing the number of securities for which registration is sought), and to file the same, with all exhibits thereto and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact, proxies and agents full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith, as fully for all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact, proxies and agents, or their or his or her substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Act of 1933, this Registration Statement on Form S-3 has been signed by the following persons in the capacities and on the dates indicated.

Signature	Title	Date
/s/ Nick Glover Dr. Nick Glover	President, Chief Executive Officer and Director (Principal Executive Officer)	August 1, 2016
/s/ Sukhi Jagpal Sukhi Jagpal	Chief Financial Officer (Principal Financial Officer and Principal Accounting Officer)	August 1, 2016
/s/ Donald Parfet Donald Parfet	Chairman of the Board	August 1, 2016
/s/ Jeffrey H. Cooper Jeffrey H. Cooper	Director	August 1, 2016
/s/ Tran Nguyen Tran Nguyen	Director	August 1, 2016
/s/ Nicole Onetto Nicole Onetto	Director	August 1, 2016
/s/ Robert Pelzer Robert Pelzer	Director	August 1, 2016
/s/ James Topper James Topper	Director	August 1, 2016

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EXHIBIT INDEX

		Incorporated by Reference
Exhibit Number	Description of Document	Form		File No.		Exhibit		Filing Date		Filed Herewith
1.1*	Form of Underwriting Agreement.
3.1	Restated Certificate of Incorporation.		S-1		333-204921		3.2		6/12/2015
3.2	Restated Bylaws.		S-1		333-204921		3.4		6/12/2015
4.1	Form of Common Stock Certificate.		S-1		333-204921		4.1		7/6/2015
4.2	Third Amended and Restated Investors’ Rights Agreement, dated April 17, 2014, by and among the Registrant and certain of its stockholders.		S-1		333-204921		4.2		6/12/2015
4.3*	Form of Preferred Stock Certificate.
4.4	Form of Debt Security.										X
4.5	Form of Indenture.										X
4.6*	Form of Warrant.
4.7*	Form of Warrant Agreement.
4.8*	Form of Subscription Rights Certificate
4.9*	Form of Unit.
4.10*	Form of Unit Agreement.
5.1	Opinion of Fenwick & West LLP.										X
12.1	Statement of Computation of Ratio of Earnings to Fixed Charges and Ratio of Combined Fixed Charges and Preferred Stock Dividends.										X
23.1	Consent of independent registered public accounting firm.										X
23.2	Consent of Fenwick & West LLP (included in Exhibit 5.1).										X
24.1	Power of Attorney (reference is made to signature page hereto).										X
25.1**	Form T-1 Statement of Eligibility of Trustee for Senior Indenture under The Trust Indenture Act of 1939.
25.2**	Form T-1 Statement of Eligibility of Trustee for Subordinated Indenture under The Trust Indenture Act of 1939.

* To be filed by amendment or as an exhibit to a report pursuant to Section 13(a) or 15(d) of the Exchange Act, and incorporated herein by reference.

** To be filed in accordance with the requirements of Section 305(b)(2) of the Trust Indenture Act of 1939 and Rule 5b-3 thereunder.