As filed with the Securities and Exchange Commission on March 25, 2024

Registration
No. 333-   

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM S-3

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

Lexicon Pharmaceuticals, Inc.

(Exact name of Registrant as specified in its charter)

As filed with the Securities and Exchange Commission on August 6, 2021Delaware76-0474169
Registration No. 333-
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
____________________
FORM S-3
REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933

Lexicon Pharmaceuticals, Inc.
(Exact name of registrant as specified in its charter)
Delaware

(State or other jurisdiction of

incorporation or organization)

76-0474169
(I.R.S. Employer
Identification No.)
____________________

2445 Technology Forest Blvd., 11th Floor
The Woodlands, Texas 77381-1160
(281) 863-3000
(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

Number)
____________________
Lonnel Coats
President and Chief Executive Officer

2445 Technology Forest Blvd., 11th Floor

The Woodlands, Texas 77381-1160

(281) 863-3000

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

Lonnel Coats

Chief Executive Officer

2445 Technology Forest Blvd., 11th Floor

The Woodlands, Texas 77381

(281) 863-3000

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

____________________
copies

Copies to:

David P. Oelman

Jackson A. O’Maley
Vinson & Elkins L.L.P.
1001 Fannin,845 Texas Avenue, Suite 2500
4700

Houston, Texas 77002-6760
77002

(713) 758-2222

Brian T. Crum
Senior Vice President and General Counsel
Lexicon Pharmaceuticals, Inc.
2445 Technology Forest Blvd., 11th Floor
The Woodlands, Texas 77381
(281) 863-3000
____________________

Approximate date of commencement of proposed sale to the public:

From time to time after the effective date of this registration statement becomes effective, subject to market conditions and other factors.

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. o

☐

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. þ

☒

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

☐

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. o

☐

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

☐

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. o



☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.  Large accelerated filer o   Accelerated filer  þNon-accelerated filer o   Smaller reporting company  þ Emerging growth company o

Large accelerated filer☐Accelerated filer☐
Non-accelerated filer☒Smaller reporting company☒
Emerging growth company☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a)7(a)(2)(B) of the ExchangeSecurities Act. o


____________________


CALCULATION OF REGISTRATION FEE

Title of Each Class of
Securities to be Registered (1)

Amount to be Registered (2) (4)		Proposed Maximum
Aggregate Offering
Price Per Unit (3) (4)		Proposed Maximum
Aggregate
Offering Price (4)		Amount of
Registration Fee (5)
Common Stock, par value $0.001N/A
Preferred Stock, par value $0.01N/A
Debt SecuritiesN/A
WarrantsN/A
RightsN/A
UnitsN/A
   Total$200,000,000$200,000,000$21,820
(1)    Securities registered hereunder may be sold separately, together or as units with other securities registered hereunder.
(2)    There are being registered hereunder such indeterminate (i) number of shares of common stock and preferred stock, (ii) principal amount of debt securities, (iii) number of warrants to purchase common stock, preferred stock or debt securities, (iv) number of rights to purchase common stock, preferred stock, debt securities or other securities and (v) number of units comprised of one or more shares of common stock, preferred stock, debt securities or warrants in any combination, as shall have an aggregate initial offering price not to exceed $200,000,000. If any debt securities are issued at an original issued discount, then the offering price of such debt securities shall be in such greater principal amount as shall result in an aggregate initial offering price not to exceed $200,000,000, less the aggregate dollar amount of all securities previously issued hereunder. Any securities registered hereunder may be sold separately or as units with other securities registered hereunder. The securities registered also include such indeterminate numbers of shares of common stock and preferred stock and amount of debt securities as may be issued upon conversion of or exchange for preferred stock or debt securities that provide for conversion or exchange, upon exercise of warrants or rights or pursuant to the antidilution provisions of any such securities. The securities registered also include, pursuant to Rule 416 under the Securities Act, such additional number of shares of common stock that may become issuable as a result of any stock split, stock dividends or similar event.
(3)    The proposed maximum initial offering price per security or unit will be determined, from time to time, by the registrant in connection with the issuance by the registrant of the securities registered hereunder.
(4)    The amount to be registered, proposed maximum aggregate offering price per unit and proposed maximum aggregate offering price are not specified as to each class of security pursuant to General Instruction II.D. of Form S-3 under the Securities Act.
(5)    Calculated pursuant to Rule 457(o) under the Securities Act.

☐

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 Commission, acting pursuant to said Section 8(a), may determine.







The information in this prospectus is not complete and may be changed. WeThese securities may not sell these securitiesbe sold until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus is not an offer to sell these securities andnor does it is not solicitingseek an offer to buy these securities in any statejurisdiction where the offer or sale is not permitted.


Subject to Completion, Dated March 25, 2024


SUBJECT TO COMPLETION, DATED AUGUST 6, 2021




$200,000,000
lexiconuniversalshelf_imag.jpg
Lexicon Pharmaceuticals, Inc.

PROSPECTUS

LOGO

57,661,250 Shares of Common Stock

This prospectus relates to the proposed offer and resale by selling stockholders of shares of our common stock to be issued by us directly to the selling stockholders identified in this prospectus under “Selling Stockholders,” of up to 57,661,250 shares of our common stock, $0.001 par value per share, issuable upon conversion of outstanding shares of our Series A Convertible Preferred Stock,

Debt Securities
Warrants
Rights
Units

__________________

$0.01 par value per share.

We will not receive any proceeds from the sale of the shares offered by the selling stockholders.

The selling stockholders may offer common stock, preferred stock, debt securities, warrants and/or rights, either individually or in units,and sell the shares from time to time in onethrough public or more offerings in amounts,private transactions at prevailing market prices, at prices and on termsrelated to be determined in light ofprevailing market conditionsprices or at the time of sale. We may also offer common stock or preferred stock upon conversion of debt securities, common stock upon conversion of preferred stock or common stock, preferred stock or debt securities upon the exercise of warrants or rights.


Each time we sell these securities, we will provide a supplement to this prospectus that contains specific information about the offering. The supplement may also add, update or change information contained in this prospectus. You should carefully read this prospectus and any supplement before you invest.

privately negotiated prices.

Our common stock is listed on The Nasdaq Global Select Market under the symbol “LXRX”. The prospectus supplement will contain information, where applicable, regarding any other listing on The Nasdaq Global Select Market or any securities exchange of the securities covered by the prospectus supplement. The last reported sale price ofon March 22, 2024 was $2.26 per share.

Investing in our common stock on August 4, 2021 was $3.41 per share.


Investing in our securities involves risks. See “Risk Factors”“Risk Factors” beginning on page 6.
5.

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      , 2021.2024.






TABLE OF CONTENTS

About This Prospectus

1

Lexicon Pharmaceuticals, Inc.

2

Risk Factors

5

Special Note Regarding Forward-Looking Statements

6

Use of Proceeds

7

Selling Stockholders

8

Description of Capital Stock

12

Plan of Distribution

17

Legal Matters

21

Experts

21

Where You Can Find More Information

22

Documents Incorporated by Reference

23

You should rely only on the information contained in this prospectus and documents incorporated into this prospectus by reference. We have not authorized anyone to provide you with information different from that contained in this prospectus or the documents incorporated by reference herein. This prospectus may only be used where it is legal to sell these securities. The information contained in this prospectus, the documents incorporated by reference herein and any supplements to this prospectus are accurate only as of the dates of their respective covers or earlier dates as specified therein, regardless of the time of delivery of this prospectus or any supplement to this prospectus or of any sale of these securities.

In this prospectus, “Lexicon,” “Lexicon Pharmaceuticals,” “we,” “us” and “our” refer to Lexicon Pharmaceuticals, Inc. and its subsidiaries. We own or have rights to trademarks or trade names that we use in connection with the operation of our business. The Lexicon name and logo and INPEFA® are registered trademarks and INPEFA Together™ is a trademark of Lexicon Pharmaceuticals, Inc.

i

PagePage
About This Prospectus3Special Note Regarding Forward Looking
Lexicon Pharmaceuticals, Inc.4   Statements24
Risk Factors6Use of Proceeds25
Description of Capital Stock7Plan of Distribution26
Description of Debt Securities11Legal Matters28
Description of Warrants16Experts28
Description of Rights18Where You Can Find More Information28
Description of Units20Documents Incorporated by Reference28
Legal Ownership of Securities21





ABOUT THIS PROSPECTUS

This prospectus is part of a “shelf” registration statement that we filed with the Securities and Exchange Commission, or the SEC. Under this shelf registration process, we may sell, from time to time, an indeterminate amount of any combination of the securities describedselling stockholders identified in this prospectus in one or more offerings. Thismay use this prospectus provides you with a general descriptionto sell up to an aggregate 57,661,250 shares of the securities we may offer, which is not meantour common stock, referred to be a complete descriptionherein as our “common stock,” issuable upon conversion of each security.outstanding shares of our Series A Convertible Preferred Stock, $0.01 par value per share, referred to herein as our “Series A preferred stock.” Each time that wethe selling stockholders offer and sell securities,shares of our common stock, a prospectus supplement containing specific information about the terms of that offering will be provided, including the specific amounts, prices and terms of the securitiescommon stock offered and the manner in which they will be offered. The prospectus supplement and any other offering material may also add to, update or change information contained in this prospectus or in documents we have incorporated by reference into this prospectus. We urge you to read both this prospectus and any prospectus supplement and any other offering material (including any free writing prospectus) prepared by or on behalf of us for a specific offering of securities,the shares covered hereby, together with the additional information described under the heading “Where You Can Find More Information” on page 28 of this prospectus.

In this prospectus, “Lexicon,” “Lexicon Pharmaceuticals,” “we,” “us” and “our” refer to Lexicon Pharmaceuticals, Inc. and its subsidiaries. We own or have rights to trademarks or trade names that we use in connection with the operation of our business. The Lexicon name and logo are registered trademarks of Lexicon Pharmaceuticals, Inc.

You should rely only on the information contained in this prospectus, any prospectus supplement or any free writing prospectus prepared by or on behalf of us and any documents incorporated into this prospectus by reference. We and the selling stockholders have not authorized anyone to provide you with information different from that contained in this prospectus or the documents incorporated by reference herein. We and the selling stockholders take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. WeThe selling stockholders are not making an offer to sell or soliciting an offer to purchase these securitiesthe shares covered hereby in any jurisdiction where the offer or sale is not permitted. This prospectus may only be used where it is legal to sell these securities.the shares covered hereby. The information contained in this prospectus, the documents incorporated by reference herein and any supplements to this prospectus are accurate only as of the dates of their respective covers or earlier dates as specified therein, regardless of the time of delivery of this prospectus or any supplement to this prospectus or of any sale of these securities.the shares covered hereby.

1

3

LEXICON PHARMACEUTICALS, INC.

We are

Lexicon Pharmaceuticals is a biopharmaceutical company with a mission of pioneering medicines that transform patients’ lives. We are devoting most of our resources to the commercialization of our approved drug, INPEFA® (sotagliflozin), for heart failure and the research and development of our most advanced drug candidates:

We are commercializing INPEFA, an orally-delivered small molecule drug, in the United States to reduce the risk of cardiovascular death, hospitalization for heart failure, and urgent heart failure visit in adults with heart failure or type 2 diabetes mellitus, chronic kidney disease, or CKD, and other cardiovascular risk factors.

We are separately pursuing regulatory approval of sotagliflozin as a treatment for type 1 diabetes. The U.S. Food and Drug Administration, or FDA, issued a complete response letter regarding our New Drug Application, or NDA, for sotagliflozin in type 1 diabetes in March 2019, which we appealed. Following recent discussions with the FDA, we are now preparing to resubmit our NDA for patients with type 1 diabetes and CKD. We have reported positive results from three Phase 3 clinical trials of sotagliflozin in type 1 diabetes.

We are also developing sotagliflozin as a treatment for hypertrophic cardiomyopathy, or HCM, and are preparing to initiate a Phase 3 clinical trial of sotagliflozin in HCM.

•

We are developing LX9211, an orally-delivered small molecule drug candidate, as a treatment for neuropathic pain. We have reported results from two Phase 1 clinical trials of LX9211 and are now conducting a Phase 22b clinical trial of LX9211 in diabetic peripheral neuropathic pain, or DPNP, and a second Phase 2 clinical trial of LX9211 in post-herpetic neuralgia. LX9211 hashave received Fast Track designation from the FDA for development of LX9211 in diabetic peripheral neuropathic pain.that indication. We have reported positive results from a Phase 2 clinical trial of LX9211 in DPNP and top-line results from a separate Phase 2 clinical trial of LX9211 in post-herpetic neuralgia which also demonstrated evidence of effect.

•

We are developing sotagliflozin,conducting preclinical development of LX9851, an orally-delivered small molecule drug candidate, as a treatment for heart failureobesity and type 1 diabetes. We have reported positive results from two Phase 3 clinical trials evaluating the effect of sotagliflozin on long-term outcomes related to cardiovascular death and heart failure in approximately 10,500 and 1,200 patients, respectively. We are now preparing an applicationtool for regulatory approval to market sotagliflozin for heart failure in the United States and, if approved, for the commercial launch of sotagliflozin in the United States.weight management.

We have reported positive results from three Phase 3 clinical trials evaluating the effect of sotagliflozin on type 1 diabetes in approximately 800, 800 and 1,400 patients, respectively. The FDA issued a complete response letter regarding our application for regulatory approval to market sotagliflozin for type 1 diabetes in the United States and, at our request, has issued a public Notice of Opportunity for Hearing on whether there are grounds for denying approval of our application. Sotagliflozin has been approved in the European Union for use as an adjunct to insulin therapy in the treatment of type 1 diabetes, but has not yet been commercially launched.

•

We are conducting preclinical research and development and preparing to conduct clinical development of compounds from a number of additional drug programs originating from our internal drug discovery efforts.

LX9211 originated from our collaborative neuroscience drug discovery efforts with Bristol-Myers Squibb, and sotagliflozin

INPEFA, LX9851 and compounds from a number of additional drug programs originated from our own internal drug discovery efforts. Thoseefforts, and LX9211 originated from our collaborative neuroscience drug discovery efforts with Bristol-Myers Squibb. Our efforts were driven by a systematic, target biology-driven approach in which we used gene knockout technologies and an integrated platform of advanced medical technologies to systematically study the physiological and behavioral functions of almost 5,000 genes in mice and assessed the utility of the proteins encoded by the corresponding human genes as potential drug targets. We have identified and validated in living animals, or in vivo, more than 100 targets with promising profiles for drug discovery.


We are workinghave worked both independently and through collaborations and strategic alliances with third parties to capitalize on our drug target discoveries and drug discoveryresearch and development programs. We seek to retain exclusive or co-exclusive rights to the benefits of certain drug discoveryresearch and development programs by developing and commercializing drug candidates from those programs internally, particularly in the United States for indications treated by specialist physicians. We seek to collaborate with other pharmaceutical and biotechnology companies with respect to drug discovery or the research, development and commercialization of certain of our drug candidates, particularly with respect to commercialization in territories outside the United States or commercialization in the United States for indications treated by primary care physicians, or when the collaboration may otherwise provide us with access to expertise and resources that we do not possess internally or are complementary to our own. Our collaborations and strategic alliances include arrangements with TerSera Therapeutics LLC, under which we are eligible to receive milestone and royalty payments relating to telotristat ethyl in biliary tract cancer, and with Genentech, Inc., under which we are eligible to receive milestone and royalty payments relating to its UTTR1147a (IL-22 Fc) biotherapeutic drug candidate.


Lexicon Pharmaceuticals was incorporated in Delaware in July 1995 and commenced operations in September 1995. Our corporate headquarters are located at 2445 Technology Forest Blvd., 11th Floor, The

2

Woodlands, Texas 77381, and our telephone number is (281) 863-3000. Our common stock is listed on The Nasdaq Global Select Market under the symbol “LXRX.”

4

Our annual report on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, and amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934 as amended, or the Exchange Act, are made available free of charge on our corporate website located at www.lexpharma.com as soon as reasonably practicable after the filing of those reports with the Securities and Exchange Commission. Information found on or through our website is not incorporated herein by reference and should not be considered part of this prospectus or any prospectus supplement.prospectus.

3

THE OFFERING

Common Stock Offered by the Selling Stockholders

Up to 57,661,250 shares of our common stock issuable upon conversion of outstanding shares of our Series A preferred stock.

Terms of this Offering

The selling stockholders may sell the shares of our common stock offered by this prospectus from time to time on terms to be determined at the time of sale through ordinary brokerage transactions or through any other means described in this prospectus. Such shares may be sold at fixed prices, at market prices prevailing at the time of sale, at prices related to prevailing market price or at negotiated prices. See “Plan of Distribution” beginning on page 15.

Common stock and Series A preferred Stock outstanding prior to and immediately after the conversion of the Series A preferred stock

We currently have 246,236,753 shares of common stock outstanding and 2,304,147 shares of Series A preferred stock outstanding. Following the conversion of the Series A preferred stock, we will have 361,444,103 shares of common stock outstanding and no shares of Series A preferred stock outstanding.

Use of Proceeds

We are not selling any securities under this prospectus, and we will not receive any proceeds from the sale of shares of our common stock by the selling stockholders under this prospectus. All proceeds from the sale of shares of our common stock offered by this prospectus will be for the account of the selling stockholders.

Registration Rights

We have filed the registration statement on Form S-3, of which this prospectus forms a part, to satisfy registration rights we granted to the selling stockholders in the Private Placement.

Nasdaq Capital Market Symbol

LXRX

Risk Factors

Investing in our securities involves a high degree of risk and purchasers of our common stock may lose their entire investment. See the information contained in or incorporated by reference under “Risk Factors” beginning on page 5 of this prospectus, and in the documents incorporated by reference into this prospectus, before deciding to invest in our securities.

4

5

RISK FACTORS

An investment in our securitiescommon stock involves a significant degree of risk. Before you invest in our securities, youYou should carefully consider thosethe risk factors described under, but not limited to, the heading “Riskset forth in “Item 1A. Risk Factors” inof our most recent annual reportAnnual Report on Form 10-K anyand our subsequently filed quarterly reportsQuarterly Reports on Form 10-Q, and any subsequently filed current reports on Form 8-K (excluding any information furnished pursuant to Item 2.02 or Item 7.01 on any current report on Form 8-K), which are incorporated herein by reference, and those risk factors that may be included in any applicable prospectus supplement, together with all of the other information included in, or incorporated by reference into, this prospectus any prospectus supplement and the documents we incorporate by reference, inwhen evaluating an investment in our securities.common stock. If any of these risks were actually to occur, our business, financial condition or results of operations could be materially adversely affected. AdditionalIn that case, the trading price of our common stock could decline and you could lose all or part of your investment.

The conversion of the Series A preferred stock to common stock is subject to certain conditions.

According to the terms and subject to the conditions set forth in the Certificate of Designations relating to the Series A preferred stock, each share of Series A preferred stock will automatically convert into 50 shares (subject to adjustments) of Common Stock immediately following the satisfaction of all of the following conditions: (i) the approval of the Sixth Amended and Restated Certificate of Incorporation of the Corporation (the “New Charter”) by our stockholders (the “Stockholder Approval”), which shall increase the total authorized shares of common stock to 450,000,000, (ii) the adoption of the New Charter by our board of directors and (iii) the filing and acceptance of the New Charter with and by the Secretary of State of the State of Delaware, which shall be filed the same day as the date of Stockholder Approval.

The number of shares being registered for offer and resale is significant in relation to the number of our outstanding shares of common stock.

We have filed a registration statement of which this prospectus is a part to register the offer and resale of the shares offered hereunder for sale into the public market by the selling stockholders. Following the conversion of the Series A preferred stock to common stock, the shares being offered hereunder will represent approximately 16% of our common stock, and if sold in the market all at once or at about the same time, could affect the market price of our common stock during the period the registration statement remains effective and could also affect our ability to raise equity capital.

5

SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus and the documents incorporated by reference into this prospectus contain certain information regarding our financial projections, plans and strategies that are forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 and 21E of the Securities Exchange Act of 1934. We have attempted to identify forward-looking statements by terminology including “anticipate,” “believe,” “can,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “plan,” “potential,” “predict,” “should” or “will” or the negative of these terms or other comparable terminology. These statements, which are only predictions and involve known and unknown risks, uncertainties and other important factors may include, among other things, statements which address our strategy and operating performance, events or developments that we expect or anticipate will occur in the future, such as projections of our future results of operations or of our financial condition, the status of any collaborative agreements or clinical trials, the expected timing of the completion of our ongoing and future clinical trials and the results of such trials, including top-line data, expected timing of initiation of our planned clinical trials, expected enrollment in our ongoing and future clinical trials, and our research and development efforts and anticipated trends in our business.

We have based these forward-looking statements on our current expectations and projections about future events. However, there may be events in the future that we are not presently knownable to predict accurately or which we do not fully control that could cause actual results to differ materially from those expressed or implied in our forward-looking statements. Many important factors could cause actual results to differ materially from those expressed or implied by these forward-looking statements, including those discussed under “Risk Factors” in this prospectus and any prospectus supplement and other sections of the documents incorporated by reference into this prospectus. Except as required by applicable law, we undertake no obligation to publicly release any revisions to the forward-looking statements or reflect events or circumstances after the date of this prospectus.

6

USE OF PROCEEDS

All of the shares offered by this prospectus are being offered and sold by the selling stockholders. We will not receive any proceeds from the sale of the shares of common stock offered by the selling stockholders.

We will pay all expenses for the registration of the selling stockholders’ offer and sale of the shares of common stock covered by this prospectus, including registration fees, the costs and expenses of our counsel and independent public accountants. The selling stockholders will pay any underwriting discounts and commissions which they incur in selling shares of our common stock.

7

SELLING STOCKHOLDERS

On March 11, 2024, we entered into a Preferred Stock Purchase Agreement with certain accredited investors, including the selling stockholders listed below (the “Purchase Agreement”), pursuant to which we agreed to sell 2,304,147 shares of Series A preferred stock of the Company, par value $0.01 per share, at a price of $108.50 per share in a private placement (the “Private Placement”). Each share of Series A preferred stock is convertible into 50 shares of our common stock, par value $0.001 per share. We are registering the offering and resale by the selling stockholders of the shares of common stock covered by this prospectus pursuant to the registration rights provisions of the Purchase Agreement.

The selling stockholders may offer and sell the shares of common stock covered by this prospectus from time to time. Our registration of the selling stockholders’ offer and sale of such shares does not necessarily mean that the selling stockholders will sell any or all of their shares. We do not know when or in what amounts the selling stockholders may offer shares for sale. Because the selling stockholders may offer and sell all or some of the shares pursuant to this offering, and because there are currently no agreements, arrangements or understandings with respect to the sale of any of the shares, we cannot estimate the number of the shares that will be held by the selling stockholders after completion of the offering.

The below table sets forth certain information with respect to each selling stockholder, including (a) the shares of our common stock beneficially owned by such selling stockholder prior to this offering, (b) the number of shares of our common stock that may be offered by such selling stockholder pursuant to this prospectus and (c) such selling stockholder’s beneficial ownership of our common stock after completion of this offering, assuming that all of the shares of common stock covered by this prospectus (but none of the other shares, if any, held by the selling stockholders) are sold to third parties in this offering.

The table below sets forth the beneficial ownership of all common stock held by each selling stockholder as of March 22, 2024 and the number of shares of common stock offered by this prospectus. Percentage of ownership is based on 361,444,103 shares of common stock, which includes (i) 246,236,753 shares of common stock outstanding on March 22, 2024 and (ii) 115,207,350 shares of common stock issuable upon conversion of the Series A preferred stock.

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We prepared this table based on information supplied to us or thatby the selling stockholders, and we currently believe are immaterial may also significantly impair our business operations and financial condition.have not sought to independently verify such information.

Name of Selling Stockholders

  Beneficially Owned Before
Offering		  Shares of
Common
Stock That
May Be
Offered
Under this
Prospectus		   Beneficially Owned After
Offering(1)		 
  Number   Percentage   Number   Percentage 

Point72 Associates, LLC(2)

   9,701,240    2.7%   9,216,600    484,640    * 

Fidelity Growth Company Commingled Pool (3)

   14,123,437    3.9%   8,760,800    5,362,637    1.5% 

Braidwell Partners Master Fund LP(4)

   8,294,950    2.3%   8,294,950    —     —  

Fidelity Mt. Vernon Street Trust: Fidelity Growth Company Fund (3)

   10,072,650    2.8%   6,020,850    4,051,800    1.1% 

Fidelity Select Portfolios: Biotechnology Portfolio(3)

   6,751,610    1.9%   4,608,300    2,143,310    * 

Entities affiliated with Great Point Partners (5)

   4,608,250    1.3%   4,608,250    —     —  

Entities affiliated with OrbiMed(6)

   5,846,100    1.6%   2,304,100    3,542,000    * 

Fidelity Mt. Vernon Street Trust: Fidelity Growth Company K6 Fund (3)

   3,365,151    *   2,108,250    1,256,901    * 

Citadel CEMF Investments LTD. (7)

   2,073,750    *   2,073,750    —     —  

CVI Investments, Inc. (8)

   1,670,500    *   1,670,500    —     —  

Fidelity Mt. Vernon Street Trust: Fidelity Series Growth Company Fund (3)

   2,617,450    *   1,543,250    1,074,200    * 

Altium Growth Fund, LP (9)

   1,382,500    *   1,382,500    —     —  

Woodline Master Fund LP (10)

   1,382,500    *   1,382,500    —     —  

Schonfeld Global Master Fund L.P. (11)

   1,882,500    *   1,382,500    500,000    * 

BLACKWELL PARTNERS LLC – SERIES A (12)

   1,138,350    *   1,138,350    —     —  

Pinehurst Partners, L.P. (13)

   460,850    *   460,850    —     —  

NANTAHALA CAPITAL PARTNERS LIMITED PARTNERSHIP (13)

   381,000    *   381,000    —     —  

NCP RFM LP (13)

   323,950    *   323,950    —     —  

*

Represents less than one percent of outstanding shares of common stock.

(1)

Assumes that all of the shares of common stock being registered for offer and resale by this prospectus are resold by the selling stockholders to third parties.

(2)

Point72 Asset Management, L.P. maintains investment and voting power with respect to the securities held by certain investment funds it manages, including Point72 Associates, LLC. Point72 Capital Advisors, Inc. is the general partner of Point72 Asset Management, L.P. Mr. Steven A. Cohen controls each of Point72 Asset Management, L.P. and Point72 Capital Advisors, Inc.

(3)

These funds and accounts are managed by direct or indirect subsidiaries of FMR LLC. Abigail P. Johnson is a Director, the Chairman and the Chief Executive Officer of FMR LLC. Members of the Johnson family, including Abigail P. Johnson, are the predominant owners, directly or through trusts, of Series B voting common shares of FMR LLC, representing 49% of the voting power of FMR LLC. The Johnson family group and all other Series B shareholders have entered into a shareholders’ voting agreement under which all Series B voting common shares will be voted in accordance with the majority vote of Series B voting common shares. Accordingly, through their ownership of voting common shares and the execution of the shareholders’ voting agreement, members of the Johnson family may be deemed, under the Investment Company Act of 1940, to form a controlling group with respect to FMR LLC. The address of these funds and accounts is 245 Summer Street, Boston, MA 02210.

(4)

Represents shares of common stock issuable upon the conversion of Series A preferred stock held directly by Braidwell Partners Master Fund LP (“Master Fund”). The general partner of Master Fund is Braidwell

9

For more information about our SEC filings, please see “Where You Can Find More Information” and “Documents Incorporated By Reference” on page 28 of this prospectus. See also “Special Note Regarding Forward-Looking Statements” on page 24 of this prospectus.
GP LLC (the “Master Fund GP”), and the investment manager of Master Fund is Braidwell LP. The general partner of each of Braidwell LP and the Master Fund GP is Braidwell Management LLC (“Braidwell Management”). Alex Karnal and Brian Kreiter are the managing members of Braidwell Management and may be deemed to share voting and investment power with respect to the shares held directly by Master Fund. Mr. Karnal and Mr. Kreiter disclaim beneficial ownership of the shares held by Master Fund except to the extent of their pecuniary interests in such shares, if any. The address of each of these entities and individuals is c/o Braidwell GP LLC, One Harbor Point, 2200 Atlantic Street, Stamford, CT 06902.
(5)

Consists of (i) 2,543,750 shares of Common Stock issuable upon the conversion of Series A preferred stock held by Biomedical Value Fund, L.P. (“BVF”), (ii) 1,751,150 shares of Common Stock issuable upon the conversion of Series A Preferred Stock held by Biomedical Offshore Value Fund, LTD. (“BOVF”) and (iii) 313,350 shares of Common Stock issuable upon the conversion of Series A Preferred Stock held by Cheyne Select Master Fund ICAV – Cheyne Global Equity Fund (“CGEF” and, together with BVF and BOVF, the “GPP Entities”). Great Point Partners, LLC (“GPP LLC”) is the investment manager of BVF and BOVF and the sub-advisor to CGEF, and by virtue of such status may be deemed to be the beneficial owner of the shares held by the GPP Entities. Each of Dr. Jeffrey R. Jay, M.D., as Senior Managing Member of GPP LLC, and Mr. Ortav Yehudai, as Managing Director of GPP LLC, has voting and investment power with respect to shares held by the GPP Entities, and therefore may be deemed to be the beneficial owner of the shares held by the GPP Entities. Notwithstanding the above, GPP LLC, Dr. Jay and Mr. Yehudai disclaim beneficial ownership of the shares held by the GPP Entities except to the extent of their respective pecuniary interests. The principal business address of the GPP Entities is 165 Mason Street, 3rd Floor, Greenwich, CT 06830.

(6)

Consists of (i) 951,000 shares of Common Stock held by The Biotech Growth Trust PLC (“BIOG”), (ii) 1,050,000 shares of Common Stock held by OrbiMed Genesis Master Fund, L.P. (“Genesis Master Fund”), (iii) 1,541,000 shares of Common Stock held by OrbiMed Partners Master Fund Limited (“OPM”), (iv) 1,152,050 shares of Common Stock issuable upon the conversion of Series A preferred stock held by BIOG, and (v) 1,152,050 shares of Common Stock issuable upon the conversion of Series A preferred stock held by Genesis Master Fund. OrbiMed Capital LLC (“OrbiMed Capital”) is the portfolio manager to BIOG. OrbiMed Capital is the investment advisor to OPM. OrbiMed Genesis GP LLC (“Genesis GP”) is the general partner of Genesis Master Fund. OrbiMed Advisors LLC (“OrbiMed Advisors”) is the managing member of Genesis GP. OrbiMed Capital is a relying advisor of OrbiMed Advisors. OrbiMed Advisors and OrbiMed Capital exercise voting and investment power through a management committee comprised of Carl L. Gordon, Sven H. Borho, and W. Carter Neild, each of whom disclaims beneficial ownership of the shares held by BIOG, Genesis Master Fund, and OPM. The business address of the OrbiMed entities is c/o OrbiMed Advisors LLC, 601 Lexington Avenue, 54th Floor, New York, NY 10022.

(7)

The shares reported under “Beneficially Owned before Offering” represent 2,073,750 shares of Common Stock issuable upon conversion of the 41,475 shares of Series A preferred stock, par value $0.01 per share purchased in the Private Placement. Citadel Advisors LLC is the portfolio manager of Citadel CEMF Investments Ltd. Citadel Advisors Holdings LP is the sole member of Citadel Advisors LLC. Citadel GP LLC is the General Partner of Citadel Advisors Holdings LP. Kenneth Griffin owns a controlling interest in Citadel GP LLC. Mr. Griffin, as the owner of a controlling interest in Citadel GP LLC, may be deemed to have shared power to vote and/or shared power to dispose of the securities held by Citadel CEMF Investments Ltd. This disclosure shall not be construed as an admission that Mr. Griffin or any of the Citadel related entities listed above is the beneficial owner of any securities of the Company other than the securities actually owned by such person (if any). The address of Citadel CEMF Investments Ltd. is c/o Citadel Enterprise Americas LLC, Southeast Financial Center, 200 S. Biscayne Blvd., Suite 3300, Miami, FL 33131.

(8)

Heights Capital Management, Inc., the authorized agent of CVI Investments, Inc. (“CVI”), has discretionary authority to vote and dispose of the shares held by CVI and may be deemed to be the beneficial owner of these shares. Martin Kobinger, in his capacity as Investment Manager of Heights Capital Management, Inc., may also be deemed to have investment discretion and voting power over the shares held by CVI. Mr. Kobinger disclaims any such beneficial ownership of the shares. CVI Investments, Inc.is affiliated with

10

one or more FINRA member, none of whom are currently expected to participate in the sale pursuant to the prospectus contained in the Registration Statement of Shares purchased by the Investor in this Offering.
(9)

Consists of 1,382,500 Shares directly held by Altium Growth Fund, LP. Altium Capital Management, LP, the investment manager of Altium Growth Fund, LP, has voting and investment power over these securities. Jacob Gottlieb is the managing member of Altium Capital Growth GP, LLC, which is the general partner of Altium Growth Fund, LP. Each of Altium Growth Fund, LP and Jacob Gottlieb disclaims beneficial ownership over these shares. The principal address of Altium Capital Management, LP is 152 West 57th Street, 20th Floor, New York, NY 10019.

(10)

Woodline Partners LP serves as the investment manager of Woodline Master Fund LP and may be deemed to be the beneficial owner of the shares. Woodline Partners LP disclaims any beneficial ownership of these shares. The address of the Fund is 4 Embarcadero Center, Suite 3450, San Francisco, CA 94111.

(11)

These securities are directly held by Schonfeld Global Master Fund LP (“Schonfeld Master”). Schonfeld Strategic Advisors LLC is a Registered Investment Adviser and has been delegated the legal power to voteand/or direct the disposition of such securities on behalf of Schonfeld Master as a general partner or investment manager and would be considered the beneficial owner of such securities. The above shall not be deemed to be an admission by the record owners or Schonfeld Master that they are themselves beneficial owners of these securities for purposes of Section 13(d) of the Securities Exchange Act of 1934, as amended, or any other purpose. The address of Schonfeld Master is 590 Madison Ave, Floor 23, New York, NY 10022.

(12)

Nantahala Capital Management, LLC is a Registered Investment Adviser and has been delegated the legal power to vote and/or direct the disposition of such securities on behalf of these selling stockholders as a General Partner, Investment Manager, or Sub-Advisor and would be considered the beneficial owner of such securities. The above shall not be deemed to be an admission by the record owners or the selling stockholder that they are themselves beneficial owners of these securities for purposes of Section 13(d) of the Securities Exchange Act of 1934, as amended, or the Exchange Act, or any other purpose. Wilmot Harkey and Daniel Mack are managing members of Nantahala Capital Management, LLC and may be deemed to have voting and dispositive power over the shares held by the selling stockholder.

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6

DESCRIPTION OF CAPITAL STOCK

Our authorized capital stock consists of 230300 million shares of common stock, $0.001 par value, and five million shares of preferred stock, $0.01 par value. As of August 4, 2021,March 22, 2024, there were 144,474,452246,236,753 shares of our common stock issued and outstanding, 1,164,9981,528,008 shares of our common stock issued and held in treasury and no2,304,147 shares of Series A preferred stock outstanding.

The following summary description of our capital stock is based on the provisions of our secondfifth amended and restated certificate of incorporation, our second amended and restated bylaws and the applicable provisions of the Delaware General Corporation Law. This information may not be complete in all respects and is qualified entirely by reference to the provisions of our secondfifth amended and restated certificate of incorporation, second amended and restated bylaws and the Delaware General Corporation Law. For information on how to obtain copies of our secondfifth amended and restated certificate of incorporation and second amended and restated bylaws, see “Where You Can Find More Information” on page 2822 of this prospectus.

Common Stock

The holders of common stock are entitled to one vote for each share held of record on all matters submitted to a vote of the stockholders and do not have cumulative voting rights. Accordingly, holders of a majority of the shares of common stock entitled to vote in any election of directors may elect all of the directors standing for election. Subject to preferences that may be applicable to any outstanding shares of preferred stock, the holders of common stock are entitled to receive ratably such dividends as may be declared by the board of directors out of funds legally available therefor. Upon the liquidation, dissolution or winding up of Lexicon, holders of our common stock are entitled to share ratably in all assets remaining after payment of liabilities and the liquidation preferences of any outstanding shares of preferred stock. Holders of 20% or more of our issued and outstanding common stock have (a) customary preemptive rights related to the issuance of certain of our securities and (b) consent rights prior us taking any of the following actions: (i) creating or issuing any new class or series of shares of capital stock (or securities convertible into or exercisable for shares of capital stock) having rights, preferences or privileges senior to or on parity with the common stock, (ii) subject to certain exceptions, repurchasing, retiring, redeeming or otherwise acquiring any of our equity securities (or securities convertible into or exchangeable for equity securities) or any subsidiary and (iii) adopting, or proposing to adopt, or maintaining any shareholders’ rights plan, “poison pill” or other similar plan or agreement, unless such stockholder is exempt from such plan or agreement. There are no redemption or sinking fund provisions applicable to our common stock. All outstanding shares of our common stock are, and all shares of common stock that may be issued under this prospectus will be, fully paid and non-assessable.

Preferred Stock

Pursuant to our secondfifth amended and restated certificate of incorporation, our board of directors has the authority, without further action by the stockholders, to issue up to five million shares of preferred stock, in one or more series. Our board of directors is authorized to fix or alter from time to time the designation, powers, preferences and rights of the shares of each series of preferred stock, including dividend rights, conversion rights, voting rights, terms of redemption, liquidation preferences and sinking fund terms. Our board of directors may also establish from time to time the number of shares constituting any series of preferred stock, and to increase or decrease the number of shares of any series subsequent to the issuance of shares of that series, but not below the number of shares of any series then outstanding.

We will fix the rights, preferences, privileges and restrictions of the preferred stock of each series in the certificate of designation relating to that series. We will incorporate by reference as an exhibit to the registration statement that includes this prospectus or as an exhibit to a report filed under the Exchange Act, the form of any

12

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 will include:

•    

the title and stated value;

•    

the number of shares we are offering;

•    

the liquidation preference per share;

•    

the purchase price;

7

•    

the dividend rate, period and payment date and method of calculation for dividends;

•    

whether dividends will be cumulative or non-cumulative and, if cumulative, the date from which dividends will accumulate;

•    

the provisions for a sinking fund, if any;

•    

the provisions for redemption or repurchase, if applicable, and any restrictions on our ability to exercise those redemption and repurchase rights;

•    

whether the preferred stock will be convertible into our common stock, and, if applicable, the conversion price, or how it will be calculated, and the conversion period;

•    

whether the preferred stock will be exchangeable into debt securities, and, if applicable, the exchange price, or how it will be calculated, and the exchange period;

•    

voting rights, if any, of the preferred stock;

•    

preemption rights, if any;

•    

restrictions on transfer, sale or other assignment, if any;

•    

the relative ranking and preferences of the preferred stock as to dividend rights and rights if we liquidate, dissolve or wind up our affairs;

•    

any limitations on issuance of any class or series of preferred stock ranking senior to or on a parity with the series of preferred stock as to dividend rights and rights if we liquidate, dissolve or wind up our affairs; and

•    

any other specific terms, preferences, rights or limitations of, or restrictions on, the preferred stock.

If we issue shares of preferred stock under this prospectus, the shares will be fully paid and non-assessable and will not have, or be subject to, any preemptive or similar rights.

The Delaware General Corporation Law provides that the holders of preferred stock will have the right to vote separately as a class on any proposal involving fundamental changes in the rights of holders of that preferred stock. This right is in addition to any voting rights that may be provided for in the applicable certificate of designation.

The issuance of preferred stock could adversely affect the voting power, conversion or other rights of holders of common stock. Preferred stock could be issued quickly with terms designed to delay or prevent a change in control of our company or make removal of management more difficult. Additionally, the issuance of preferred stock may have the effect of decreasing the market price of our common stock.

Series A Convertible Preferred Stock

On March 12, 2024, we filed with the Secretary of State of the State of Delaware to be effective upon filing a Certificate of Designations of Series A Convertible Preferred Stock (the “Certificate of Designations”), in the form approved and adopted by our board of directors, which sets forth the terms of the Series A preferred stock.

13

According to the terms and subject to the conditions set forth in the Certificate of Designations, each share of Series A preferred stock will automatically convert into 50 shares (subject to adjustments) of our common stock, immediately following the satisfaction of all of the following conditions: (i) the approval of the New Charter, which would increase the total authorized shares of common stock under the New Charter from 300,000,000 to 450,000,000, by our stockholders at the upcoming 2024 annual meeting of our stockholders, (ii) the adoption of the New Charter by our board of directors and (iii) the filing and acceptance of the New Charter with and by the Secretary of State of the State of Delaware. The holders of the Series A preferred stock are entitled to vote on an as-converted basis on all matters and not as a separate class vote, except as required by Delaware law.

Arrangements with Invus

In June 2007, we entered into a securities purchase agreement with Invus, L.P., under which Invus, L.P. made an initial investment in our common stock in August 2007. Invus, L.P. and its affiliates, which we collectively refer to as Invus, have subsequently made additional investments in our common stock and currently own approximately 52.3%50.0% of our outstanding common stock.

Board of Directors. Concurrently with the execution of the securities purchase agreement, we entered into a stockholders’ agreement with Invus, L.P. under which Invus has the right to designate a number of directors equal to the percentage of all the outstanding shares of our common stock owned by Invus, rounded up to the nearest whole number of directors. Invus has designated three of the nine current members of our board of directors. While Invus has not presently exercised its director designation rights in full, it may exercise them at any time in the future in its sole discretion. To facilitate the exercise of such rights, we have agreed, upon written request from Invus, to take all necessary actions in accordance with our obligations under the stockholders’ agreement to (a) increase the number of directors to the number specified by Invus (which number shall be no greater than reasonably necessary for the exercise of Invus’ director designation rights under the stockholders’ agreement) and (b) cause the appointment to the newly created directorships of directors so designated by Invus pursuant to its rights under the stockholders’ agreement.

8

Invus also has the right to require proportionate representation of Invus-appointed directors on the audit, compensation and corporate governance committees of our board of directors, subject to certain restrictions. Invus-designated directors currently serve as one of the three members of each of the compensation committee and the corporate governance committee of our board of directors. No Invus-designated directors currently serve on the audit committee of our board of directors.

The provisions of the stockholders’ agreement relating to Invus’ rights to designate members of our board of directors and its audit, compensation and corporate governance committees will terminate if the percentage of all the outstanding shares of our common stock owned by Invus and its affiliates falls below 10%. Invus also has the right to terminate these provisions at any time in its discretion.

Registration Rights. Concurrently with the execution of the securities purchase agreement, we also entered into a registration rights agreement with Invus, L.P., pursuant to which Invus has certain demand and piggyback registration rights with respect to shares of our common stock held by them. Invus has waived these registration rights with respect to any offerings of our securities pursuant to this prospectus.

Preemptive and Consent Rights.Rights. Our second amendedFifth Amended and restated certificateRestated Certificate of incorporationIncorporation grants holders of 20% or more of our issued and outstanding common stock (a) customary preemptive rights related to the issuance of certain of our securities and (b) consent rights prior us taking any of the following actions: (i) creating or issuing any new class or series of shares of capital stock (or securities convertible into or exercisable for shares of capital stock) having rights, preferences or privileges senior to or on parity with the common stock, (ii) subject to certain exceptions, repurchasing, retiring, redeeming or otherwise acquiring any of our equity securities (or securities convertible into or exchangeable for equity securities) or any subsidiary and (iii) adopting, or proposing to adopt, or maintaining any shareholders’ rights plan, “poison pill” or other similar

14

plan or agreement, unless such stockholder is exempt from such plan or agreement. BasedInvus possesses such preemptive and consent rights based on Invus’its current ownership interest in our common stock.

2023 Purchase Agreement. In May 2023, we entered into a purchase agreement with Invus pursuant to which, among other things, we issued to Invus shares of our common stock at a price and on the terms as offered to the public in a concurrent underwritten offering. The purchase agreement contains customary representations and warranties and covenants through incorporation by reference to those made in the underwriting agreement relating to the concurrent underwritten offering. The purchase agreement also contains customary obligations of the parties and termination provisions and served to waive certain preemptive rights held by Invus possesseswith respect to the concurrent underwritten offering. Following the transactions contemplated by the purchase agreement and the underwriting agreement relating to the concurrent underwritten offering, Invus held approximately the same percentage of our common stock following such preemptivetransactions as it did before such transactions.

2024 Purchase Agreement. In March 2024, we entered into the Purchase Agreement described herein with certain purchasers, including Invus. Following the conversion of the Series A preferred stock issued in the Private Placement, Invus will hold approximately the same percentage of our common stock as it did before the Private Placement.

Invus Letter Agreements. In connection with the Private Placement, we entered into letter agreements with Invus whereby Invus agreed, among other things, to vote all of the voting securities of our company then held by Invus and consent rights.

entitled to vote thereon in favor of the approval of the New Charter.

Anti-Takeover Effects of Provisions of Delaware Law and Our Charter Documents

Delaware Takeover Statute. We are subject to the provisions of Section 203 of the Delaware General Corporation Law. In general, the statute prohibits a publicly-held Delaware corporation such as Lexicon from engaging in a business combination with an interested stockholder for a period of three years after the date of the transaction in which the person became an interested stockholder, unless the business combination is approved in a prescribed manner. For purposes of Section 203, a business combination includes a merger, asset sale or other transaction 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, did own) 15% or more of our voting stock.

Charter Documents. Our secondfifth amended and restated certificate of incorporation requires that any action required or permitted to be taken by our stockholders must be effected at a duly called annual or special meeting of stockholders and may not be effected by a consent in writing. Additionally, our secondfifth amended and restated certificate of incorporation:

•    

does not provide for the use of cumulative voting in the election of directors;

•    

provides for a board of directors, classified into three classes of directors;

•    

provides that the authorized number of directors may be changed only by resolution of our board of directors; and

•    

provides for the authority of our board of directors to issue up to five million shares of “blank check” preferred stock and to determine the price, powers, preferences and rights of these shares, without stockholder approval.

Our second amended and restated bylaws provide that candidates for director may be nominated only by our board of directors or by a stockholder who gives written notice to us not less than 120 days nor more than 150 days in advance of the first anniversary of the date of our proxy statement relating to the previous year’s annual meeting of stockholders. The authorized number of directors is fixed in accordance with our secondfifth amended and restated certificate of incorporation. Our board of directors currently consists of nineeight members, divided into

15

three classes. As a result, a portion of the board of directors will be elected each year. The board of directors may appoint new

9

directors to fill vacancies or newly created directorships. Our second amended and restated bylaws also limit who may call a special meeting of stockholders.

Delaware law and these charter provisions may have the effect of deterring hostile takeovers or delaying changes in control of our management, which could depress the market price of our common stock.

Transfer Agent and Registrar

The transfer agent and registrar for our common stock is Computershare Inc. The transfer agent for any series of preferred stock will be named and described in the prospectus supplement for that series.

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10

DESCRIPTION

PLAN OF DEBT SECURITIES

The following description, togetherDISTRIBUTION

We are registering the resale of the shares of common stock covered by this prospectus on behalf of the selling stockholders. All costs, expenses and fees connected with the additional information we may include in any applicable prospectus supplements, summarizesregistration of such shares of common stock will be borne by us. Any brokerage commissions and similar expenses connected with selling such shares of common stock will be borne by the material terms and provisions of the debt securities that weselling stockholders. The selling stockholders may offer under this prospectus and the related indenture. While the terms summarized below will apply generallysell such shares of common stock from time to any debt securities we may offer under this prospectus, we will describe the particular terms of any debt securities that we may offer in more detail in the applicable prospectus supplement. If we so indicate in the prospectus supplement, the terms of any debt securities offered under that prospectus supplement may differ from the terms described below. However, no prospectus supplement shall fundamentally change the terms that are set forth in this prospectus or offer a security that is not registered and described in this prospectus at the time of its effectiveness.

We may offer debt securities in the form of either senior debt securities or subordinated debt securities. Unless otherwise specified in a supplement to this prospectus, the debt securities will be our direct, unsecured obligations and will rank equally with all of our other unsecured and unsubordinated indebtedness.
The debt securities will be issued under an indenture between us and a trustee. The following summary of the general features of the debt securities to be governed by the indenture is subject to, and qualified in its entirety by reference to, the provisions of the indenture applicable to a particular series of debt securities. We have filed a form of indenture as an exhibit to the registration statement which includes this prospectus. Capitalized terms used in the summary have the meanings specified in the indenture.
General
The terms of each series of debt securities will be established by or pursuant to a resolution of our board of directors, or a committee thereof, and set forth or determined in the manner provided in an officer’s certificate or by a supplemental indenture. The particular terms of each series of debt securities will be described in a prospectus supplement relating to such series, including any pricing supplement.
We can issue an unlimited amount of debt securities under the indenture that may be in one or more series with the same or various maturities, at par, at a premium or at a discount. We will set forth in a prospectus supplement, including any pricing supplement, relating to any series of debt securities being offered, the aggregate principal amount and the following terms of the debt securities:
•    the title of the debt securities;
•    the price or prices (expressed as a percentage of the principal amount) at which we will sell the debt securities;
•    any limit on the aggregate principal amount of the debt securities;
•    the date or dates on which we will pay the principal on the debt securities;
•    the rate or rates (which may be fixed or variable) per annum or the methodtransactions. As used to determine the rate or rates (including any commodity, commodity index, stock exchange index or financial index) at which the debt securities will bear interest, the date or dates from which interest will accrue, the date or dates on which interest will commence and be payable and any regular record date for the interest payable on any interest payment date;
•    the place or places where principal of, and interest, if any, on, the debt securities will be payable;
•    the terms and conditions upon which we may redeem the debt securities;
•    any obligation we have to redeem or purchase the debt securities pursuant to any sinking fund or analogous provisions or at the option of a holder of debt securities;
•    the dates on which and the price or prices at which we will repurchase debt securities at the option of the holders of debt securities and other detailed terms and provisions of these repurchase obligations;
•    the denominations in which the debt securities will be issued, if other than denominations of $1,000 and any integral multiple thereof;
11

•    whether the debt securities will be issued in the form of certificated debt securities or global debt securities;
•    the portion of principal amount of the debt securities payable upon declaration of acceleration of the maturity date, if other than the principal amount;
•    the currency of denomination of the debt securities;
•    the designation of the currency, currencies or currency units in which payment of principal of, and premium and interest on, the debt securities will be made;
•    if payments of principal of, or premium or interest on, the debt securities will be made in one or more currencies or currency units other than that or those in which the debt securities are denominated, the manner in which the exchange rate with respect to these payments will be determined;
•    the manner in which the amounts of payment of principal of, or premium or interest on, the debt securities will be determined, if these amounts may be determined by reference to an index based on a currency or currencies other than that in which the debt securities are denominated or designated to be payable or by reference to a commodity, commodity index, stock exchange index or financial index;
•    any provisions relating to any security provided for the debt securities;
•    any addition to or change in the events of default described in this prospectus, the term “selling stockholders” includes pledgees, donees, transferees and other successors-in-interest who may acquire such shares of common stock through a pledge, gift, partnership distribution or other non-sale related transfer from the selling stockholders. The selling stockholders will act independently of the Company in the indenturemaking decisions with respect to the debt securitiestiming, manner and any change size of each sale. These transactions include:

in “at the acceleration provisions described in this prospectus or inmarket offerings” within the indenture with respect tomeaning of Rule 415(a)(4) under the debt securities;

•    any additionSecurities Act, to or changethrough a market maker or into an existing trading market, on an exchange or otherwise;

directly to a limited number of purchasers or to a single purchaser;

through agents;

by delayed delivery contracts or by remarketing firms;

ordinary brokerage transactions and transactions in which the covenants described in this prospectus or inbroker solicits purchasers;

purchases by a broker-dealer as principal and resale by the indenture with respect to the debt securities;

•    any conversion provisions, including the conversion price, the conversion period, provisions as to whether conversion will be mandatory, at the option of the holder or at our option, the events requiring an adjustment of the conversion price and provisions affecting conversion if such series of debt securities are redeemed;
•    whether the debt securities will be senior debt securities or subordinated debt securities and, if applicable, a description of the subordination terms thereof;
•    any depositaries, interest rate calculation agents, exchange rate calculation agents or other agents with respect to the debt securities; and
•    any other terms of the debt securities, which may modify, delete, supplement or add to any provision of the indenture as it applies to that series.
We may issue debt securities that providebroker-dealer for an amount less than their stated principal amount to be due and payable upon declaration of acceleration of their maturityits own account pursuant to the terms of the indenture. We will provide you with information on the federal income tax considerations and other special considerations applicable to any of these debt securities in the applicable prospectus supplement.this prospectus;

If we denominate the purchase price of any of the debt securities in a foreign currency

exchange or currencies or a foreign currency unit or units, or if the principal of, and premium and interest on, any series of debt securities is payable in a foreign currency or currencies or a foreign currency unit or units, we will provide you with information on the restrictions, elections, general tax considerations, specific terms and other information with respect to that issue of debt securities and such foreign currency or currencies or foreign currency unit or units in the applicable prospectus supplement.

Transfer and Exchange
Each debt security will be represented by either one or more global securities registered in the name of The Depository Trust Company, as Depositary, or a nominee (we will refer to any debt security represented by a global debt security as a “book-entry debt security”), or a certificate issued in definitive registered form (we will refer to any debt security represented by a certificated security as a “certificated debt security”) as set forth in the applicable
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over-the-counter
prospectus supplement. Except as set forth under the heading “Legal Ownership of Securities” below, book-entry securities will not be issuable in certificated form.
You may transfer or exchange certificated debt securities at any office we maintain for this purpose distributions in accordance with the termsrules of the indenture. No service charge will be made for any transfer or exchange of certificated debt securities, but we may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection with a transfer or exchange.market;

You may effect the transfer

settlement of certificated debt securities and the right to receive the principal of, and any premium and interest on, certificated debt securities only by surrendering the certificate representing those certificated debt securities and either reissuance by us or the trustee of the certificate to the new holder or the issuance by us or the trustee of a new certificate to the new holder.

No Protection in the Event of a Change of Control
Unless we state otherwise in the applicable prospectus supplement, the debt securities will not contain any provisions which may afford holders of the debt securities protection in the event we have a change in control or in the event of a highly leveraged transaction (whether or not such transaction results in a change in control) which could adversely affect holders of debt securities.
Covenants
We will set forth in the applicable prospectus supplement any restrictive covenants applicable to any issue of debt securities.
Consolidation, Merger and Sale of Assets
We may not consolidate with or merge with orshort sales entered into or convey, transfer or lease all or substantially all of our properties and assets to, any person, which we refer to as a successor person, unless:
•    we are the surviving corporation or the successor person (if other than Lexicon) is organized and validly existing under the laws of any U.S. domestic jurisdiction and expressly assumes our obligations on the debt securities and under the indenture;
•    immediately after giving effect to the transaction, no event of default, and no event which, after notice or lapse of time, or both, would become an event of default, shall have occurred and be continuing under the indenture; and
•    certain other conditions are met.
Events of Default
Event of default means, with respect to any series of debt securities, any of the following:
•    default in the payment of any interest upon any debt security of that series when it becomes due and payable, and continuance of that default for a period of 30 days (unless the entire amount of the payment is deposited by us with the trustee or with a paying agent prior to the expiration of the 30-day period);
•    default in the payment of principal of or premium on any debt security of that series when due and payable;
•    default in the deposit of any sinking fund payment, when and as due in respect of any debt security of that series;
•    default in the performance or breach of any other covenant or warranty by us in the indenture (other than a covenant or warranty that has been included in the indenture solely for the benefit of a series of debt securities other than that series), which default continues uncured for a period of 90 days after we receive written notice from the trustee or we and the trustee receive written notice from the holders of not less than a majority in principal amount of the outstanding debt securities of that series as provided in the indenture;
•    certain events of bankruptcy, insolvency or reorganization of our company; and
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•    any other event of default provided with respect to debt securities of that series that is described in the applicable prospectus supplement accompanying this prospectus.
No event of default with respect to a particular series of debt securities (except as to certain events of bankruptcy, insolvency or reorganization) necessarily constitutes an event of default with respect to any other series of debt securities. The occurrence of an event of default may constitute an event of default under our bank credit agreements in existence from time to time. In addition, the occurrence of certain events of default or an acceleration under the indenture may constitute an event of default under certain of our other indebtedness outstanding from time to time.
If an event of default with respect to debt securities of any series at the time outstanding occurs and is continuing, then the trustee or the holders of not less than a majority in principal amount of the outstanding debt securities of that series may, by a notice in writing to us (and to the trustee if given by the holders), declare to be due and payable immediately the principal (or, if the debt securities of that series are discount securities, that portion of the principal amount as may be specified in the terms of that series) of, and accrued and unpaid interest, if any, on all debt securities of that series. In the case of an event of default resulting from certain events of bankruptcy, insolvency or reorganization, the principal (or such specified amount) of and accrued and unpaid interest, if any, on all outstanding debt securities will become and be immediately due and payable without any declaration or other act on the part of the trustee or any holder of outstanding debt securities. At any time after a declaration of acceleration with respect to debt securities of any series has been made, but before a judgment or decree for payment of the money due has been obtained by the trustee, the holders of a majority in principal amount of the outstanding debt securities of that series may rescind and annul the acceleration if all events of default, other than the non-payment of accelerated principal and interest, if any, with respect to debt securities of that series, have been cured or waived as provided in the indenture. We refer you to the prospectus supplement relating to any series of debt securities that are discount securities for the particular provisions relating to acceleration of a portion of the principal amount of such discount securities upon the occurrence of an event of default.
The indenture provides that the trustee will be under no obligation to exercise any of its rights or powers under the indenture at the request of any holder of outstanding debt securities, unless the trustee receives indemnity satisfactory to it against any loss, liability or expense. Subject to certain rights of the trustee, the holders of a majority in principal amount of the outstanding debt securities of any series will have the right to direct the time, method and place of conducting any proceeding for any remedy available to the trustee or exercising any trust or power conferred on the trustee with respect to the debt securities of that series.
No holder of any debt security of any series will have any right to institute any proceeding, judicial or otherwise, with respect to the indenture or for the appointment of a receiver or trustee, or for any remedy under the indenture, unless:
•    that holder has previously given to the trustee written notice of a continuing event of default with respect to debt securities of that series; and
•    the holders of at least a majority in principal amount of the outstanding debt securities of that series have made written request, and offered reasonable indemnity, to the trustee to institute the proceeding as trustee, and the trustee has not received from the holders of a majority in principal amount of the outstanding debt securities of that series a direction inconsistent with that request and has failed to institute the proceeding within 60 days.
Notwithstanding the foregoing, the holder of any debt security will have an absolute and unconditional right to receive payment of the principal of, and any premium and interest on, that debt security on or after the due dates expressed in that debt security and to institute suit for the enforcementeffective date of payment.
If any securities are outstanding under the indenture, the indenture requires us, within 120 days after the end of our fiscal year, to furnish to the trustee a statement as to compliance with the indenture. The indenture provides that the trustee may withhold notice to the holders of debt securities of any series of any default or event of default (except in payment on any debt securities of that series) with respect to debt securities of that series if it in good faith determines that withholding notice is in the interest of the holders of those debt securities.
Modification and Waiver
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We may modify and amend the indenture with the consent of the holders of at least a majority in principal amount of the outstanding debt securities of each series affected by the modifications or amendments. We may not make any modification or amendment without the consent of the holders of each affected debt security then outstanding if that amendment will:
•    reduce the amount of debt securities whose holders must consent to an amendment or waiver;
•    reduce the rate of or extend the time for payment of interest (including default interest) on any debt security;
•    reduce the principal of or premium on or change the fixed maturity of any debt security or reduce the amount of, or postpone the date fixed for, the payment of any sinking fund or analogous obligation with respect to any series of debt securities;
•    reduce the principal amount of discount securities payable upon acceleration of maturity;
•    waive a default in the payment of the principal of, or premium or interest on, any debt security (except a rescission of acceleration of the debt securities of any series by the holders of at least a majority in aggregate principal amount of the then outstanding debt securities of that series and a waiver of the payment default that resulted from such acceleration);
•    make the principal of, or premium or interest on, any debt security payable in currency other than that stated in the debt security;
•    make any change to certain provisions of the indenture relating to, among other things, the right of holders of debt securities to receive payment of the principal of, and premium and interest on, those debt securities and to institute suit for the enforcement of any such payment and to waivers or amendments; or
•    waive a redemption payment with respect to any debt security.
Except for certain specified provisions, the holders of at least a majority in principal amount of the outstanding debt securities of any series may on behalf of the holders of all debt securities of that series waive our compliance with provisions of the indenture. The holders of a majority in principal amount of the outstanding debt securities of any series may on behalf of the holders of all the debt securities of such series waive any past default under the indenture with respect to that series and its consequences, except a default in the payment of the principal of, or any premium or interest on, any debt security of that series or in respect of a covenant or provision, which cannot be modified or amended without the consent of the holder of each outstanding debt security of the series affected; provided, however, that the holders of a majority in principal amount of the outstanding debt securities of any series may rescind an acceleration and its consequences, including any related payment default that resulted from the acceleration.
Discharge of Indenture
The indenture provides that, unless otherwise provided by the terms of the applicable series of debt securities, we may be discharged from any and all obligations in respect of the debt securities of any series (except for certain obligations to register the transfer or exchange of debt securities of such series, to replace stolen, lost or mutilated debt securities of such series, and to maintain paying agencies and certain provisions relating to the treatment of funds held by paying agents). We will be so discharged upon satisfying the requirements in the indenture, including the deposit with the trustee, in trust, of money and/or U.S. government obligations or, in the case of debt securities denominated in a single currency other than U.S. dollars, foreign government obligations, that, through the payment of interest and principal in accordance with their terms, will provide money in an amount sufficient in the opinion of a nationally recognized firm of independent public accountants to pay and discharge each installment of principal of, premium and interest on and any mandatory sinking fund payments in respect of the debt securities of that series on the stated maturity of those payments in accordance with the terms of the indenture and those debt securities.
Governing Law
The indenture 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
The following description, together with the additional information we may include in any applicable prospectus supplements, summarizes the material terms and provisions of the warrants that we may offer under this prospectus and the related warrant agreements and warrant certificates. While the terms summarized below will apply generally to any warrants that we may offer under this prospectus, we will describe the particular terms of any series of warrants that we may offer in more detail in the applicable prospectus supplement. If we indicate in the prospectus supplement, the terms of any warrants offered under that prospectus supplement may differ from the terms described below. However, no prospectus supplement shall fundamentally change the terms that are set forth in this prospectus or offer a security that is not registered and described in this prospectus at the time of its effectiveness. Specific warrant agreements will contain additional important terms and provisions and will be incorporated by reference as an exhibit to the registration statement that includes this prospectus or as an exhibit to a report filed under the Exchange Act.
General
We will describe in the applicable prospectus supplement the terms of the series of warrants, including:
•    the offering price and aggregate number of warrants offered;
•    the currency for which the warrants may be purchased;
•    if applicable, the designation and terms of the securities with which the warrants are issued and the number of warrants issued with each such security or each principal amount of such security;
•    if applicable, the date on and after which the warrants and the related securities will be separately transferable;
•    in the case of warrants to purchase common stock or preferred stock, the number of shares of common stock or preferred stock, as the case may be, purchasable upon the exercise of one warrant and the price at which these shares may be purchased upon such exercise;
•    in the case of warrants to purchase debt securities, the principal amount of debt securities purchasable upon exercise of one warrant and the price at, and currency in which, this principal amount of debt securities may be purchased upon such exercise;
•    the effect of any merger, consolidation, sale or other disposition of our business on the warrant agreements and the warrants;
•    the terms of any rights to redeem or call the warrants;
•    any provisions for changes to or adjustments in the exercise price or number of securities issuable upon exercise of the warrants;
•    the dates on which the right to exercise the warrants will commence and expire;
•    the manner in which the warrant agreements and warrants may be modified;
•    federal income tax consequences of holding or exercising the warrants;
•    the terms of the securities issuable upon exercise of the warrants; and
•    any other specific terms, preferences, rights or limitations of or restrictions on the warrants.
Before exercising their warrants, holders of warrants will not have any of the rights of holders of the securities purchasable upon such exercise, including:
•    in the case of warrants to purchase common stock or preferred stock, the right to receive dividends, if any, or, payments upon our liquidation, dissolution or winding up or to exercise voting rights, if any; or
•    in the case of warrants to purchase debt securities, the right to receive payments of principal of, or premium, if any, or interest on, the debt securities purchasable upon exercise or to enforce covenants in the applicable indenture.
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Exercise of Warrants
Each warrant will entitle the holder to purchase the securities that we specify in the applicable prospectus supplement at the exercise price that we describe in the applicable prospectus supplement. Unless we otherwise specify in the applicable prospectus supplement, holders of the warrants may exercise the warrants at any time up to the specified time on the expiration date that we set forth in the applicable prospectus supplement. After the close of business on the expiration date, unexercised warrants will become void.
Holders of the warrants may exercise the warrants by delivering the warrant certificate representing the warrants to be exercised together with specified information, and paying the required amount to the warrant agent in immediately available funds, as provided in the applicable prospectus supplement. We will set forth on the reverse side of the warrant certificate and in the applicable prospectus supplement the information that the holder of the warrant will be required to deliver to the warrant agent.
Upon receipt of the required payment and the warrant certificate properly completed and duly executed at the corporate trust office of the warrant agent or any other office indicated in the applicable prospectus supplement, we will issue and deliver the securities purchasable upon such exercise. If fewer than all of the warrants represented by the warrant certificate are exercised, then we will issue a new warrant certificate for the remaining amount of warrants. If we so indicate in the applicable prospectus supplement, holders of the warrants may surrender securities as all or part of the exercise price for warrants.
Governing Law
The warrants and warrant agreements will be governed by and construed in accordance with the laws of the State of New York.
Enforceability of Rights by Holders of Warrants
Each warrant agent will act solely as our agent under the applicable warrant agreement and will not assume any obligation or relationship of agency or trust with any holder of any warrant. A single bank or trust company may act as warrant agent for more than one issue of warrants. A warrant agent will have no duty or responsibility in case of any default by us under the applicable warrant agreement or warrant, including any duty or responsibility to initiate any proceedings at law or otherwise, or to make any demand upon us. Any holder of a warrant may, without the consent of the related warrant agent or the holder of any other warrant, enforce by appropriate legal action its right to exercise, and receive the securities purchasable upon exercise of, its warrants.
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DESCRIPTION OF RIGHTS
The following description, together with the additional information we may include in any applicable prospectus supplements, summarizes the material terms and provisions of the rights that we may offer under this prospectus and the related rights agreements. While the terms summarized below will apply generally to any rights that we may offer under this prospectus, we will describe the particular terms of any series of rights that we may offer in more detail in the applicable prospectus supplement. If we indicate in the prospectus supplement, the terms of any rights offered under that prospectus supplement may differ from the terms described below. However, no prospectus supplement shall fundamentally change the terms that are set forth in this prospectus or offer a security that is not registered and described in this prospectus at the time of its effectiveness. Specific rights agreements will contain additional important terms and provisions and will be incorporated by reference as an exhibit to the registration statement that includes this prospectus or as an exhibit to a report filed under the Exchange Act.
General
We may issue rights to purchase common stock, preferred stock, debt securities or other securities. These rights may be issued independently or together with any other security offered hereby and may or may not be transferable by the stockholder receiving the rights in such offering. In connection with any offering of such 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.
Each series of rights will be issued under a separate rights agreement which we will enter into with a bank or trust company, as rights agent, all as set forth in the applicable prospectus supplement. The rights agent will act solely as our agent in connection with the certificates relating to the rights and will not assume any obligation or relationship of agency or trust with any holders of rights certificates or beneficial owners of rights. We will file the rights agreement and the rights certificates relating to each series of rights with the SEC, and incorporate them by reference as an exhibit to the registration statement of which this prospectus is a part on or beforepart;

block trades in which the time we issue a series of rights.

We will describe inbroker-dealer attempts to sell the applicable prospectus supplement the terms of the series of rights, including:
•    the date of determining the stockholders entitled to the rights distribution;
•    the number of rights issued or to be issued to each stockholder;
•    the exercise price payable for each shareshares of common stock preferred stock, debt securitiescovered by this prospectus as agent but may position and resell a portion of the block as principal to facilitate the transaction, or in crosses, in which the same broker acts as agent on both sides of the trade;

transactions in options, swaps or other securities upon the exercisederivatives that may or may not be listed on an exchange;

through distributions by a selling stockholder or its successors in interest to its members, general or limited partners or stockholders (or their respective members, general or limited partners or stockholders);

a combination of the rights;any such method of sale; or

•    the number and terms

any other method permitted pursuant to applicable law.

In connection with distributions of the shares of common stock preferred stock, debt securitiescovered by this prospectus or other securities which may be purchased per each right;

•otherwise, the extent to which the rights are transferable, if at all;
selling stockholders may:

•    the date on which the holder’s ability to exercise the rights shall commence, and the date on which the rights shall expire;
•    the extent to which the rights may include an over-subscription privilege with respect to unsubscribed securities;
•    if applicable, the material terms of any standby underwriting or purchase arrangement entered into by us in connection with the offering of

sell such rights; and

•    any other terms of the rights, including the terms, procedures, conditions and limitations relating to the exchange and exercise of the rights.
The description in the applicable prospectus supplement of any rights that we may offer will not necessarily be complete and will be qualified in its entirety by reference to the applicable rights certificate, which will be filed with the SEC.
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Exercise of Rights
Each right will entitle the holder of the right to purchase for cash such amount of shares of common stock, preferred stock, debt securities or other securities at such exercise price as shall in each case be set forth in, or be determinable as set forth in, the prospectus supplement relating to the rights offered thereby. Rights may be exercised at any time up to the close of business on the expiration date for such rights set forth in the prospectus supplement. After the close of business on the expiration date, all unexercised rights will become void.stock:

Rights may be exercised as set forth in the prospectus supplement relating to the rights offered thereby. Upon receipt of payment and the rights certificate properly completed and duly executed at the corporate trust office of the rights agent or any other office indicated in the prospectus supplement, we will forward, as soon as practicable, the shares of common stock, preferred stock, debt securities or other securities purchasable upon such exercise. We may determine to offer any unsubscribed offered securities directly to persons other than stockholders, to or through agents, underwriters or dealers or through a combination of such methods, including pursuant to standby underwriting arrangements, as set forth in the applicable prospectus supplement.
Governing Law
The rights and rights agreements will be governed by and construed in accordance with the laws of the State of New York.
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DESCRIPTION OF UNITS
The following description, together with the additional information we may include in any applicable prospectus supplements, summarizes the material terms and provisions of the units that we may offer under this prospectus and the related unit agreements. While the terms summarized below will apply generally to any units that we may offer under this prospectus, we will describe the particular terms of any series of units that we may offer in more detail in the applicable prospectus supplement. If we indicate in the prospectus supplement, the terms of any units offered under that prospectus supplement may differ from the terms described below. However, no prospectus supplement shall fundamentally change the terms that are set forth in this prospectus or offer a security that is not registered and described in this prospectus at the time of its effectiveness. Specific unit agreements will contain additional important terms and provisions and will be incorporated by reference as an exhibit to the registration statement that includes this prospectus or as an exhibit to a report filed under the Exchange Act.
General
We may issue units comprised of one or more shares of common stock, shares of preferred stock, debt securities and warrants in any combination. Each unit will be issued so that the holder of the unit is also the holder of each security included in the unit. Thus, the holder of a unit will have the rights and obligations of a holder of each included security. The unit agreement under which a unit is issued may provide that the securities included in the unit may not be held or transferred separately, at any time or at any time before a specified date.
We will describe in the applicable prospectus supplement the terms of the series of units, including:
•    the designation and terms of the units and of the securities comprising the units, including whether and under what circumstances those securities may be held or transferred separately;
•    any provisions of the governing unit agreement that differ from those described below; and
•    any provisions for the issuance, payment, settlement, transfer or exchange of the units or of the securities comprising the units.
The provisions described in this section, as well as those described under “Description of Capital Stock,” “Description of Debt Securities” and “Description of Warrants” will apply to each unit and to any common stock, preferred stock, debt security or warrant included in each unit, respectively.
Issuance in Series
We may issue units in such amounts and in numerous distinct series as we determine.
Enforceability of Rights by Holders of Units
Each unit agent will act solely as our agent under the applicable unit agreement and will not assume any obligation or relationship of agency or trust with any holder of any unit. A single bank or trust company may act as unit agent for more than one series of units. A unit agent will have no duty or responsibility in case of any default by us under the applicable unit agreement or unit, including any duty or responsibility to initiate any proceedings at law or otherwise, or to make any demand upon us. Any holder of a unit may, without the consent of the related unit agent or the holder of any other unit, enforce by appropriate legal action its rights as holder under any security included in the unit.
Title
Lexicon, the unit agents and any of their agents may treat the registered holder of any unit certificate as an absolute owner of the units evidenced by that certificate for any purpose and as the person entitled to exercise the rights attaching to the units so requested, despite any notice to the contrary. See “Legal Ownership of Securities.”
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LEGAL OWNERSHIP OF SECURITIES
We can issue securities in registered form or in the form of one or more global securities. We describe global securities in greater detail below. We refer to those persons who have securities registered in their own names on the books that we or any applicable trustee maintain for this purpose as the “holders” of those securities. These persons are the legal holders of the securities. We refer to those persons who, indirectly through others, own beneficial interests in securities that are not registered in their own names, as “indirect holders” of those securities. As we discuss below, indirect holders are not legal holders, and investors in securities issued in book-entry form or in street name will be indirect holders.
Book-Entry Holders
We may issue securities in book-entry form only, as we will specify in the applicable prospectus supplement. This means securities may be represented by one or more global securities registered in the name of a financial institution that holds them as depositary on behalf of other financial institutions that participate in the depositary’s book-entry system. These participating institutions, which are referred to as participants, in turn, hold beneficial interests in the securities on behalf of themselves or their customers.
Only the person in whose name a security is registered is recognized as the holder of that security. Securities issued in global form will be registered in the name of the depositary or its nominee. Consequently, for securities issued in global form, we will recognize only the depositary as the holder of the securities, and we will make all payments on the securities to the depositary. The depositary passes along the payments it receives to its participants, which in turn pass the payments along to their customers who are the beneficial owners. The depositary and its participants do so under agreements they have made with one another or with their customers; they are not obligated to do so under the terms of the securities.
As a result, investors in a book-entry security will not own securities directly. Instead, they will own beneficial interests in a global security, through a bank, broker or other financial institution that participates in the depositary’s book-entry system or holds an interest through a participant. As long as the securities are issued in global form, investors will be indirect holders, and not holders, of the securities.
Street Name Holders
We may terminate a global security or issue securities in non-global form. In these cases, investors may choose to hold their securities in their own names or in “street name.” Securities held by an investor in street name would be registered in the name of a bank, broker or other financial institution that the investor chooses, and the investor would hold only a beneficial interest in those securities through an account he or she maintains at that institution.
For securities held in street name, we will recognize only the intermediary banks, brokers and other financial institutions in whose names the securities are registered as the holders of those securities, and we will make all payments on those securities to them. These institutions pass along the payments they receive to their customers who are the beneficial owners, but only because they agree to do so in their customer agreements or because they are legally required to do so. Investors who hold securities in street name will be indirect holders, not holders, of those securities.
Legal Holders
Our obligations, as well as the obligations of any applicable trustee and of any third parties employed by us or a trustee, run only to the legal holders of the securities. We do not have obligations to investors who hold beneficial interests in global securities, in street name or by any other indirect means. This will be the case whether an investor chooses to be an indirect holder of a security or has no choice because we are issuing the securities only in global form.
For example, once we make a payment or give a notice to the holder, we have no further responsibility for the payment or notice even if that holder is required, under agreements with depositary participants or customers or by law, to pass it along to the indirect holders but does not do so. Similarly, we may want to obtain the approval of the holders to amend an indenture, to relieve us of the consequences of a default or of our obligation to comply with a particular provision of the indenture or for other purposes. In such an event, we would seek approval only from the
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holders, and not the indirect holders, of the securities. Whether and how the holders contact the indirect holders is up to the holders.
Special Considerations for Indirect Holders
If you hold securities through a bank, broker or other financial institution, either in book-entry form or in street name, you should check with your own institution to find out:
•    how it handles securities payments and notices;
•    whether it imposes fees or charges;
•    how it would handle a request for the holders’ consent, if ever required;
•    whether and how you can instruct it to send you securities registered in your own name so you can be a holder, if that is permitted in the future;
•    how it would exercise rights under the securities if there were a default or other event triggering the need for holders to act to protect their interests; and
•    if the securities are in book-entry form, how the depositary’s rules and procedures will affect these matters.
Global Securities
A global security is a security that represents one or any other number of individual securities held by a depositary. Generally, all securities represented by the same global securities will have the same terms.
Each security issued in book-entry form will be represented by a global security that we deposit with and register in the name of a financial institution or its nominee that we select. The financial institution that we select for this purpose is called the depositary. Unless we specify otherwise in the applicable prospectus supplement, The Depository Trust Company, New York, New York, known as DTC, will be the depositary for all securities issued in book-entry form.
A global security may not be transferred to or registered in the name of anyone other than the depositary, its nominee or a successor depositary, unless special termination situations arise. We describe those situations below under “Special Situations When a Global Security Will Be Terminated.” As a result of these arrangements, the depositary, or its nominee, will be the sole registered owner and holder of all securities represented by a global security, and investors will be permitted to own only beneficial interests in a global security. Beneficial interests must be held by means of an account with a broker, bank or other financial institution that in turn has an account with the depositary or with another institution that does. Thus, an investor whose security is represented by a global security will not be a holder of the security, but only an indirect holder of a beneficial interest in the global security.
If the prospectus supplement for a particular security indicates that the security will be issued in global form only, then the security will be represented by a global security at all times unless and until the global security is terminated. If termination occurs, we may issue the securities through another book-entry clearing system or decide that the securities may no longer be held through any book-entry clearing system.
Special Considerations for Global Securities
As an indirect holder, an investor’s rights relating to a global security will be governed by the account rules of the investor’s financial institution and of the depositary, as well as general laws relating to securities transfers. We do not recognize an indirect holder as a holder of securities and instead deal only with the depositary that holds the global security.
If securities are issued only in the form of a global security, an investor should be aware of the following:
•    An investor cannot cause the securities to be registered in his or her name, and cannot obtain non-global certificates for his or her interest in the securities, except in the special situations we describe below;
•    An investor will be an indirect holder and must look to his or her own bank or broker for payments on the securities and protection of his or her legal rights relating to the securities, as we describe above;
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•    An investor may not be able to sell interests in the securities to some insurance companies and to other institutions that are required by law to own their securities in non-book-entry form;
•    An investor may not be able to pledge his or her interest in a global security in circumstances where certificates representing the securities must be delivered to the lender or other beneficiary of the pledge in order for the pledge to be effective;
•    The depositary’s policies, which may change from time to time, will govern payments, transfers, exchanges and other matters relating to an investor’s interest in a global security. We and any applicable trustee have no responsibility for any aspect of the depositary’s actions or for its records of ownership interests in a global security. We and the trustee also do not supervise the depositary in any way;
•    The depositary may, and we understand that DTC will, require that those who purchase and sell interests in a global security within its book-entry system use immediately available funds, and your broker or bank may require you to do so as well; and
•    Financial institutions that participate in the depositary’s book-entry system, and through which an investor holds its interest in a global security, may also have their own policies affecting payments, notices and other matters relating to the securities. There may be more than one financial intermediary in the chain of ownership for an investor. We do not monitor and are not responsible for the actions of any of those intermediaries.
Special Situations When a Global Security Will Be Terminated
In a few special situations described below, the global security will terminate and interests in it will be exchanged for physical certificates representing those interests. After that exchange, the choice of whether to hold securities directly or in street name will be up to the investor. Investors must consult their own banks or brokers to find out how to have their interests in securities transferred to their own name, so that they will be direct holders. We have described the rights of holders and street name investors above.
The global security will terminate when the following special situations occur:
•    if the depositary notifies us that it is unwilling, unable or no longer qualified to continue as depositary for that global security and we do not appoint another institution to act as depositary within 90 days;
•    if we notify any applicable trustee that we wish to terminate that global security; or
•    if an event of default has occurred with regard to securities represented by that global security and has not been cured or waived.
The prospectus supplement may also list additional situations for terminating a global security that would apply only to the particular series of securities covered by the prospectus supplement. When a global security terminates, the depositary, and not we or any applicable trustee, is responsible for deciding the names of the institutions that will be the initial direct holders.
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SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS
This prospectus and the documents incorporated by reference into this prospectus contain certain information regarding our financial projections, plans and strategies that are forward-looking statements. We have attempted to identify forward-looking statements by terminology including “anticipate,” “believe,” “can,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “plan,” “potential,” “predict,” “should” or “will” or the negative of these terms or other comparable terminology. These statements, which are only predictions and involve known and unknown risks, uncertainties and other important factors may include, among other things, statements which address our strategy and operating performance, events or developments that we expect or anticipate will occur in the future, such as projections of our future results of operations or of our financial condition, the regulatory status and therapeutic and commercial potential of our drug programs, the status of any collaborative agreements or clinical trials, the expected timing of the completion of our ongoing and future clinical trials and the results of such trials, including top-line data, expected timing of initiation of our planned clinical trials, expected enrollment in our ongoing and future clinical trials, and our research and development efforts and anticipated trends in our business.
We have based these forward-looking statements on our current expectations and projections about future events. However, there may be events in the future that we are not able to predict accurately or which we do not fully control that could cause actual results to differ materially from those expressed or implied in our forward-looking statements. Many important factors could cause actual results to differ materially from those expressed or implied by these forward-looking statements, including those discussed under “Risk Factors” in this prospectus and any prospectus supplement and other sections of the documents incorporated by reference into this prospectus. As a result, you should not rely on such statements in making your investment decision. Except as required by applicable law, we undertake no obligation to publicly release any revisions to the forward-looking statements or reflect events or circumstances after the date of this prospectus.
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USE OF PROCEEDS
Except as otherwise described in the prospectus supplement relating to an offering, we intend to use the net proceeds from the sale(s) of securities offered pursuant to this prospectus and any prospectus supplement for research, development and commercialization activities and other general corporate purposes, including capital expenditures and working capital needs. We may also use some or all of the net proceeds to acquire or invest in businesses, products and technologies that are complementary to our own.
The amounts that we actually expend for working capital purposes, investments or acquisitions will vary significantly depending on a number of factors, including our future revenues, the amount of cash we generate from operations and the progress of our research, development and commercialization efforts. Accordingly, our management will retain broad discretion in the allocation of the net proceeds from the sale(s) of the offered securities. If we elect at the time of the issuance of the securities to make different or more specific use of proceeds other than as described in this prospectus, the change in use of proceeds will be described in the applicable prospectus supplement.
25

PLAN OF DISTRIBUTION
We may sell securities under this prospectus from time to time in any one or more of the following ways:
•    to or through underwriters;
•    through brokers or dealers;
•    directly to other purchasers; or
•    through agents.
We may sell securities under this prospectus from time to time

in one or more transactions:

•transactions at a fixed price or prices, which may be changed;
•    at varying prices determined at thechanged from time of sale;to time;

•    

at market prices prevailing at the timetimes of sale;

•    

at prices related to such prevailing market prices; or

•    

at negotiated prices.prices;

The prospectus supplement relating

sell such shares of common stock:

on a national securities exchange;

17

in the over-the-counter market; or

in transactions otherwise than on an exchange or in the over-the-counter market, or in combination;

enter into option or other transactions with broker-dealers or other financial institutions which require the delivery to the securities will set forth the termsthem of the offeringshares of such securities, includingcommon stock covered by this prospectus, which they may in turn resell; and

pledge the nameshares of common stock covered by this prospectus to broker-dealers or names of any underwriters, brokers, dealersother financial institutions, which, upon a default, they may in turn resell.

The selling stockholders may also resell all or agents, the name or names of any managing underwriter or underwriters, the purchase pricea portion of the securities andshares of common stock covered by this prospectus in open market transactions in reliance upon Rule 144 under the net proceeds to usSecurities Act, as permitted by that rule, Section 4(a)(1) under the Securities Act, if available, or any other exemption from such sale, any delayed delivery arrangements, any underwriting discounts and commissions and other items constituting underwriters’ compensation, any public offering price, any discounts or concessions allowed or reallowed or paid to dealers, any commissions paid to agents and any securities exchange or market on which the securities may be listed.

registration requirements that become available, rather than under this prospectus.

If we use underwriters are used in the sale of securities,any shares of common stock covered by this prospectus, such shares of common stock will be acquired by the underwriters will acquire the securities for their own account. The underwritersaccount and may resell the securitiesbe resold from time to time in one or more transactions including negotiated transactions, at a fixed public offering price or at varying prices determined at the timedescribed above. Shares of sale. Underwriterscommon stock covered by this prospectus may offer securitiesbe either offered to the public either through underwriting syndicates represented by one or more managing underwriters or directly by one or more firms acting as underwriters. UnlessWe may use underwriters with whom we inform you otherwisehave a material relationship. As applicable, we will describe in theeach accompanying prospectus supplement the obligationsname of the underwriters to purchase the securities will be subject to certain conditions,underwriter(s) and the underwriters will be obligated to purchase allnature of the offered securities if they purchase any such relationship(s).

The shares of them. The underwriters may change from time to time any public offering price and any discounts or concessions allowed or reallowed or paid to dealers.

In connection with the sale of our securities, underwriters, brokers, dealers or agents may receive compensation from us or purchasers of securities for whom they may act as agents, in the form of discounts, concessions or commissions. Underwriters, dealers and agents that participate in the distribution of our securitiescommon stock covered by this prospectus may be deemed to be underwriters, and any discounts or commissions received by them from us and any profit on the resale of securities by them may be deemed to be underwriting discounts and commissions under the Securities Act of 1933, or the Securities Act. Any person who may be deemed to be an underwriter will be identified, and the compensation received from us will be described, in the prospectus supplement.
During and after an offering through underwriters, the underwriters may purchase and sell the securities in the open market. These transactions may include over-allotment and stabilizing transactions and purchases to cover syndicate short positions created in connection with the offering. The underwriters may also impose a penalty bid, whereby selling concessions allowed to syndicate members or other broker-dealers for the securities sold for their account may be reclaimed by the syndicate if those securities are repurchased by the syndicate in stabilizing or covering transactions. These activities may stabilize, maintain or otherwise affect the market price of the securities, which may be higher than the price that might otherwise prevail in the open market, and, if commenced, may be discontinued at any time.
If dealers or brokers acting as dealers are used in the sale of the securities, we will sell the securities to such dealers or brokers as principals. The dealers or brokers acting as dealers may then resell such securities to the public
26

at varying prices to be determined by such dealers or brokers at the time of resale. The names of dealers or brokers acting as dealers and the terms of the transaction will be set forth in the prospectus supplement relating to such securities. We may sell the securities directly or through agents designated by us from time to time. AnyWe will name any agent involved in the offer oroffering and sale of the securitiessuch shares and we will be named, anddescribe any commissions that we paypaid to suchthe agent will be set forth, in the prospectus supplement relating to such securities.supplement. Unless otherwise indicated in the prospectus supplement any suchstates otherwise, the agent will be actingact on a best effortsbest-efforts basis for the period of its appointment.
We may sell securities directly, in which case no underwriters or agents would be involved. We may sell securities directly to institutional investors or others who

Agents may be deemedentitled to be underwriters within the meaning of the Securities Act with respect to any sale of those securities.

We may offer securities through agents in connection with a distribution to our stockholders of rights to purchase such securities. The terms of any such sales will be described in the prospectus supplement relating thereto. Pursuant to any standby underwriting agreement entered into in connection with a rights offering to our stockholders, persons acting as standby underwriters may receive a commitment fee for all securities underlying the rights that the underwriter commits to purchase on a standby basis. Additionally, prior to the expiration date with respect to any rights, any standby underwriters in a rights offering to our stockholders may offer such securities on a when-issued basis, including securities to be acquired through the purchase and exercise of rights, at prices set from time to timeindemnification by the standby underwriters. After the expiration date with respect to such rights, the underwriters may offer securities of the type underlying the rights, whether acquired pursuant to a standby underwriting agreement, the exercise of the rights or the purchase of such securities in the market, to the public at a price or prices to be determined by the underwriters. The standby underwriters may thus realize profits or losses independent of the underwriting discounts or commissions paid by us. If we do not enter into a standby underwriting agreement in connection with a rights offering to our stockholders, we may elect to retain a dealer-manager to manage such a rights offering for us. We also may enter into a standby arrangement with other purchasers pursuant to which such purchasers may be required to purchase any securities remaining unsubscribed for after such offering. Any such dealer-manager may offer securities of the type underlying the rights acquired or to be acquired pursuant to the purchase and exercise of rights and may thus realize profits or losses independent of any dealer-manager fee paid by us.
All securities we offer, other than common stock and other securities issued upon a reopening of a previous series, will be new issues of securities with no established trading market. Any underwriters may make a market in these securities, but will not be obligated to do so and may discontinue any market making at any time without notice. We cannot guarantee the liquidity of the trading markets for any securities.
If so indicated in the prospectus supplement, we will authorize agents, underwriters, brokers or dealers to solicit offers fromus against certain types of institutions to purchase securities at the public offering price set forth in the prospectus supplement pursuant to delayed delivery contracts providing for payment and delivery on a specified date in the future. Such contracts will be subject only to those conditions set forth in the prospectus supplement, and the prospectus supplement will set forth also the commission payable for solicitation of such contracts.
We may have agreements with the underwriters, dealers and agents to indemnify them against specific civil liabilities, including liabilities under the Securities Act, or to contributecontribution with respect to payments whichmade by the underwriters, dealersagents, under agreements between us and the agents.

Agents may receive compensation in the form of discounts, concessions or commissions from us or our purchasers, as their agents in connection with the sale of securities. These agents may be requiredconsidered to be underwriters under the Securities Act. As a result, discounts, commissions or profits on resale received by the agents may be treated as underwriting discounts and commissions. Each accompanying prospectus supplement will identify any such agent and describe any compensation received by them from us.

In connection with sales of shares of common stock covered by this prospectus, the selling stockholders may enter into hedging transactions with broker-dealers or other financial institutions, which may in turn engage in short sales of such shares of common stock in the course of hedging in positions they assume. The selling stockholders may also sell the shares of common stock covered by this prospectus short and the selling stockholders may deliver shares of common stock to close out short positions and to return borrowed shares of common stock in connection with such short sales. The selling stockholders may also loan or pledge shares of common stock covered by this prospectus to broker-dealers that in turn may sell such shares of common stock, to the extent permitted by applicable law. The selling stockholders may also enter into option or other transactions with broker-dealers or other financial institutions or the creation of one or more derivative securities which require the delivery to such broker-dealer or other financial institution of shares of common stock covered by this prospectus, which shares of common stock such broker-dealer or other financial institution may resell pursuant to this prospectus (as supplemented or amended to reflect such transaction).

The selling stockholders may, from time to time, pledge or grant a security interest in some or all of the shares of common stock covered by this prospectus owned by them and, if they default in the performance of their secured

18

obligations, the pledgees or secured parties may offer and sell such shares of common stock from time to time pursuant to this prospectus or any amendment to this prospectus under Rule 424(b)(3) or other applicable provision of the Securities Act, amending, if necessary, the list of selling stockholders to include the pledgee, transferee or other successors in interest as selling stockholders under this prospectus. The selling stockholders may also transfer and donate shares of common stock covered by this prospectus in other circumstances in which case the transferees, donees, pledgees or other successors in interest will be the selling beneficial owners for purposes of this prospectus.

A selling stockholder that is an entity may elect to make asan in-kind distribution of shares of common stock covered by this prospectus to its members, general or limited partners or stockholders pursuant to the registration statement on Form S-3, of which this prospectus forms a resultpart, by delivering a prospectus. To the extent that such members, general or limited partners or stockholders are not affiliates of those specific civil liabilities.

Underwritersours, such members, partners or stockholders would thereby receive freely tradable shares of common stock pursuant to the distribution through a registration statement. Additionally, to the extent that entities, members, partners or stockholders are affiliates of ours received shares in any such distribution, such affiliates will also be selling stockholders and agents and their affiliateswill be entitled to sell such shares pursuant to this prospectus.

Agents who may be customersbecome involved in the sale of shares of common stock covered by this prospectus may engage in transactions with, orand perform other services for, us or our subsidiaries in the ordinary course of their businesses.business for which they receive compensation.

In effecting sales, the selling stockholders may engage broker-dealers or agents, who may in turn arrange for other broker-dealers to participate. Broker-dealers or agents may receive commissions, discounts or concessions from the selling stockholders and/or from the purchasers of shares of common stock covered by this prospectus for whom the broker-dealers may act as agents or to whom they sell as principal, or both. The compensation to a particular broker-dealer may be in excess of customary commissions. To our knowledge, there is currently no plan, arrangement or understanding between any selling stockholders and any broker-dealer or agent regarding the sale of any shares of common stock by the selling stockholders.

The selling stockholders, any broker-dealers or agents and any participating broker-dealers that act in connection with the sale of the shares of common stock covered by this prospectus may be “underwriters” under the Securities Act with respect to those shares of common stock and, in such a case, will be subject to the prospectus delivery requirements of the Securities Act (it being understood that the selling stockholders shall not be deemed to be underwriters solely as a result of their participation in this offering). Any profit that the selling stockholders realize, and any compensation that any broker-dealer or agent may receive in connection with any sale, including any profit realized on resale of such shares of common stock acquired as principal, may constitute underwriting discounts and commissions. If the selling stockholders are deemed to be underwriters, the selling stockholders may be subject to certain liabilities under statutes including, but not limited to, Section 11, 12 and 17 of the Securities Act and Section 10(b) and Rule 10b-5 under the Exchange Act.

The securities laws of some states may require the selling stockholders to sell the shares of common stock covered by this prospectus in those states only through registered or licensed brokers or dealers. These laws may also require that we register or qualify such shares of common stock for sale in those states unless an exemption from registration and qualification is available and the selling stockholders and we comply with that exemption. In addition, the anti-manipulation rules of Regulation M under the Exchange Act may apply to sales of shares of common stock in the market and to the activities of the selling stockholders and their affiliates. Regulation M may restrict the ability of any person engaged in the distribution of shares of common stock to engage in market-making activities with respect to such shares of common stock. All of the foregoing may affect the marketability of the shares of common stock covered by this prospectus and the ability of any person to engage in market-making activities with respect to such shares.

If any selling stockholder notifies us that he has entered into any material arrangement with a broker-dealer for the sale of shares of common stock covered by this prospectus through a block trade, special offering, exchange

19

distribution, over-the-counter distribution or secondary distribution, or a purchase by a broker or dealer, we will file any necessary supplement to this prospectus to disclose:

the number of shares of common stock involved in the arrangement;

27

the terms of the arrangement, including the names of any underwriters, dealers or agents who purchase such shares of common stock, as required;

the proposed selling price to the public;

any discount, commission or other underwriting compensation;

the place and time of delivery for the shares of common stock being sold;

any discount, commission or concession allowed, reallowed or paid to any dealers; and

any other material terms of the distribution of the shares of common stock.

In addition, if the selling stockholder notifies us that a donee, pledgee, transferee or other successor-in-interest of the selling stockholder intends to sell any shares of common stock covered by this prospectus, we will file an amendment to the registration statement on Form S-3, of which this prospectus forms a part, or a supplement to this prospectus, if required.

20


LEGAL MATTERS

The validity of the issuance of the securities offered by this prospectus has been passed upon for us by Vinson & Elkins L.L.P., Houston, Texas.

EXPERTS

Ernst & Young LLP, independent registered public accounting firm, has audited our consolidated financial statements included in our annual report on Form 10-K for the year ended December 31, 2020, and the effectiveness of our internal control over financial reporting as of December 31, 2020,2023, as set forth in their reports,report, which areis incorporated by reference in this prospectus and elsewhere in the registration statement. Our financial statements are incorporated by reference in reliance on Ernst & Young LLP’s reports,report, given on their authority as experts in accounting and auditing.

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WHERE YOU CAN FIND MORE INFORMATION

We file annual, quarterly and current reports, proxy statements and other information with the SEC. You may read and copy the reports, proxy statements and other information that we file with the SEC at 100 F Street, NE, Washington, D.C. 20549. Please call the SEC at 1-800-SEC-0330 for information and for its prescribed rates to obtain copies of such material. The SEC also maintains a website that contains reports, proxy and information statements and other information regarding registrants, like us, that file electronically with the SEC. The address of the SEC’s Internet site is www.sec.gov.

Our annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K and other filings with the SEC are available, free of charge, through our website, as soon as reasonably practicable after those reports or filings are electronically filed with or furnished to the SEC. Information on our website or any other website is not incorporated by reference into this prospectus or any prospectus supplement and does not constitute a part of this prospectus or any prospectus supplement.

This prospectus is part of a registration statement we filed with the SEC relating to the securities we may offer. As permitted by SEC rules, this prospectus does not contain all of the information we have included in the registration statement and the accompanying exhibits and schedules we filed with the SEC. You should refer to the registration statement, exhibits and schedules for more information about us and the securities. The registration statements, exhibits and schedules are available at the SEC or through its website.

22

DOCUMENTS INCORPORATED BY REFERENCE

The SEC allows us to “incorporate by reference” the information we have filed with it, which means that we can disclose important information to you by referring you to those documents. The information we incorporate by reference is an important part of this prospectus, and later information that we file with the SEC will automatically update and supersede this information. We incorporate by reference the documents listed below that we have previously filed with the SEC and any future documents filed with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act (i) after the date on which the registration statement, of which this prospectus forms a part, was initially filed with the SEC and prior to the effectiveness of the registration statement and (ii) subsequent to the date of this prospectus and prior to the termination of the offering of the securities covered by this prospectus:

•    our annual report on Form 10-K for the year ended December 31, 2020;
•    our quarterly reports on Form 10-Q for the quarterly periods ended March 31 and June 30, 2021;
•    our current reports on Form 8-K dated January 14, February 8, March 29, April 29 and July 28, 2021; and
•    the description of our common stock contained in our registration statement on Form 8‑A filed with the SEC on March 27, 2000 pursuant to Section 12 of the Exchange Act, including any amendments and reports filed for the purpose of updating such description.

•

our Annual Report on Form 10-K for the year ended December 31, 2023, filed with the SEC on March 25, 2024;

•

our Current Reports on Form 8-K as filed with the SEC on March 11 and March 12, 2024; and

•

the description of our common stock contained in our registration statement on Form 8-A filed with the SEC on March 27, 2000 pursuant to Section 12 of the Exchange Act, including any amendments and reports filed for the purpose of updating such description.

Any statement contained in a document incorporated or deemed to be incorporated by reference in this prospectus will be deemed to be modified or superseded for purposes of this prospectus to the extent that a statement contained in this prospectus or in any other subsequently filed document which also is or is deemed to be incorporated by reference in this prospectus modifies or supersedes that statement. Any statement that is modified

28

or superseded will not constitute a part of this prospectus, except as so modified or superseded. You may rely on any statement contained in this prospectus or in documents incorporated or deemed to be incorporated in this prospectus, unless that statement has been subsequently modified or superseded as described above prior to the time you make your investment decision.

Upon your written or oral request, we will provide you at no cost a copy of any or all of the documents incorporated by reference in this prospectus, other than the exhibits to those documents, unless the exhibits are specifically incorporated by reference into this prospectus. You may request a copy of these documents by contacting:

Investor Relations

Lexicon Pharmaceuticals, Inc.
2445

8800 Technology Forest Blvd., 11th Floor
Place

The Woodlands, Texas 77381-1160

Telephone: (281) 863-3000

23



29

PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

Item 14.     Other Expenses of Issuance and Distribution.

Item 14.

Other Expenses of Issuance and Distribution

The estimated expenses payable by the Registrant in connection with the issuance and distribution of the securities being registered (other than underwriting discounts and commissions) are as follows:

SEC Registration Fee

  $20,085.49 

Accounting Fees and Expenses

   * 

Legal Fees and Expenses

   * 

Transfer Agent and Registrar Fees

   —  

Miscellaneous Expenses

   * 
  

 

 

 

Total

  $* 
  

 

 

 

SEC Registration Fee$21,820
Printing Expenses   *
Accounting Fees and Expenses   *
Legal Fees and Expenses   *
Transfer Agent and Registrar Fees   *
Miscellaneous Expenses   *
          Total$ *
*

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


The selling stockholders will pay any underwriting discounts and commissions, which discounts and commissions are not included in the foregoing table.

Item 15.     Indemnification of Directors and Officers.

Item 15.

Indemnification of Directors and Officers

Section 145 of the Delaware General Corporation Law (“DGCL”) provides that a corporation may indemnify any person who was or is a party or is threatened to be made a party to any threatened, pending or completed action, suit or proceeding whether civil, criminal, administrative or investigative (other than an action by or in the right of the corporation) by reason of the fact that he is or was a director, officer, employee or agent of the corporation, or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise, against expenses (including attorneys’ fees), judgments, fines and amounts paid in settlement actually and reasonably incurred by him in connection with such action, suit or proceeding if he acted in good faith and in a manner he reasonably believed to be in or not opposed to the best interests of the corporation, and, with respect to any criminal action or proceeding, had no reasonable cause to believe his conduct was unlawful. Section 145 further provides that a corporation similarly may indemnify any such person serving in any such capacity who was or is a party or is threatened to be made a party to any threatened, pending or completed action or suit by or in the right of the corporation to procure a judgment in its favor by reason of the fact that he is or was a director, officer, employee or agent of the corporation or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise, against expenses (including attorneys’ fees) actually and reasonably incurred in connection with the defense or settlement of such action or suit if he acted in good faith and in a manner he reasonably believed to be in or not opposed to the best interests of the corporation and except that no indemnification shall be made in respect of any claim, issue or matter as to which such person shall have been adjudged to be liable to the corporation unless and only to the extent that the Delaware Court of Chancery or such other court in which such action or suit was brought shall determine upon application that, despite the adjudication of liability but in view of all of the circumstances of the case, such person is fairly and reasonably entitled to indemnity for such expenses which the Delaware Court of Chancery or such other court shall deem proper.

Lexicon’s second

The Company’s fifth amended and restated certificate of incorporation and second amended and restated bylaws provide that indemnification shall be to the fullest extent permitted by the DGCL for all current or former directors or officers. As permitted by the DGCL, the secondfifth amended and restated certificate of incorporation provides that directors of Lexicon shall have no personal liability to Lexicon or its stockholders for monetary damages for breach of fiduciary duty as a director, except (a) for any breach of the director’s duty of loyalty to

II-1

Lexicon or its stockholders, (b) for acts or omissions not in good faith or which involve intentional misconduct or knowing violation of law, (c) under Section 174 of the DGCL or (d) for any transaction from which a director derived an improper personal benefit.

II-1

Lexicon

The Company has entered into indemnification agreements with each of its officers and directors. These agreements, among other things, require Lexicon to indemnify each officer and director for all expenses, including attorneys’ fees, liabilities, judgments, fines, penalties, excise taxes and settlement amounts incurred by any such person in any claim, action, suit or proceeding, including any action by or in the right of Lexicon, arising out of the person’s services as a director, officer, employee, agent or fiduciary to Lexicon, any subsidiary of Lexicon or to any other company or enterprise for which the person provides services at Lexicon’s request.

Other than the purported securities class action complaint captioned Daniel Manopla v. Lexicon Pharmaceuticals, Inc., Lonnel Coats, Jeffrey L. Wade and Pablo Lapuerta, M.D., as filed in the U.S. District Court for the Southern District of Texas, Houston Division and subsequently appealed by the lead plaintiffs to the U.S. Court of Appeals for the Fifth Circuit, there is no pending litigation or proceeding involving a director or officer of Lexicon as to which indemnification is being sought nor is Lexicon aware of any threatened litigation that may result in claims for indemnification by any officer or director.

II-2

Item 16.        Exhibits.

Item 16.

Exhibits

(a) Exhibits

Exhibit
Number

Exhibit No.

Description

  3.1*1.1—Form of Underwriting Agreement.
4.1—
Fifth Amended and Restated Certificate of Incorporation (filed(filed as Exhibit 3.1 to the Company’s Current Report on Form 8-K8–K dated April 26, 2012May 20, 2022 and incorporated by reference herein).
4.2
  3.2Certificate of Designations, dated March 12, 2024 (filed as Exhibit 3.1 to the Company’s Current Report on Form  8–K dated March 12, 2024 and incorporated by reference herein).
—  3.3
Second Amended and Restated Bylaws (filed as Exhibit 3.2 to the Company’s Current Report on Form  8-K8–K dated April 26, 2012 and incorporated by reference herein).
4.3
  5.1*Opinion of Vinson & Elkins L.L.P.
— 10.1
SecuritiesPreferred Stock Purchase Agreement,, dated June 17, 2007, with Invus, L.P.as of March  11, 2024, among Lexicon Pharmaceuticals, Inc. and the purchasers party thereto (filed as Exhibit 10.1 to the Company’s Current Report on Form 8-K8–K dated June 17, 2007March 11, 2024 and incorporated by reference herein).
4.4—
Amendment, dated October 7, 2009, to Securities Purchase Agreement, dated June 17, 2007, with Invus, L.P. (filed as Exhibit 10.1 to the Company’s Current Report on Form 8-K dated October 7, 2009 and incorporated by reference herein).
 23.1*4.5—
Registration Rights Agreement, dated June 17, 2007, with Invus, L.P. (filed as Exhibit 10.3 to the Company’s Current Report on Form 8-K dated June 17, 2007 and incorporated by reference herein).
4.6—
Stockholders’ Agreement, dated June 17, 2007, with Invus, L.P. (filed as Exhibit 10.4 to the Company’s Current Report on Form 8-K dated June 17, 2007 and incorporated by reference herein).
4.7—
Supplement to Transaction Agreements, dated March 15, 2010, with Invus, L.P. and Invus C.V. (filed as Exhibit 10.1 to the Company’s Current Report on Form 8-K dated March 15, 2010 and incorporated by reference herein).
4.8—
Supplement No. 2 to Transaction Agreements, dated February 23, 2012, with Invus, L.P. and Invus C.V. (filed as Exhibit 10.1 to the Company’s Current Report on Form 8-K dated February 23, 2012 and incorporated by reference herein).
4.9—
Supplement No. 3 to the Transaction Agreements, dated December 16, 2020, with Invus, L.P. and Invus C.V. (filed as Exhibit 10.1 to the Company’s Current Report on Form 8-K dated December 16, 2020 and incorporated by reference herein).
4.10—
Indenture related to the 5.25% Convertible Senior Notes due 2021, dated as of November 26, 2014, with Wells Fargo Bank, N.A. (filed as Exhibit 4.1 to the Company’s Current Report on Form 8-K dated November 26, 2014 and incorporated by reference herein).
4.11—
Form of 5.25% Convertible Senior Notes due 2021 (filed as Exhibit 4.2 to the Company’s Current Report on Form 8-K dated November 26, 2014 and incorporated by reference herein).
4.12—
*4.13—Form of Certificate of Designation of Preferred Stock.
4.14—
*4.15—Form of Note.
*4.16—Form of Common Stock Warrant Agreement and Warrant Certificate.
*4.17—Form of Preferred Stock Warrant Agreement and Warrant Certificate.
*4.18—Form of Debt Securities Warrant Agreement and Warrant Certificate.
*4.19—Form of Rights Agreement and Rights Certificate.
*4.20—Form of Unit Agreement.
5.1—
23.1—
23.2
 23.2*—Consent of Vinson & Elkins L.L.P. (contained(included in Exhibit 5.1).
24.1
 24.1*—Power of Attorney (contained in signature page).
*25.1
107*—Statement of Eligibility of Trustee under the Indenture.Filing Fee Table
        *    To be filed by amendment, as an exhibit to a report filed under the Securities Exchange Act of 1934, as amended, or as otherwise required by regulation of the Securities and Exchange Commission, and incorporated by reference herein.
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Item 17.     Undertakings.

*

Filed herewith.

Item 17.

Undertakings

The undersigned Registrant hereby undertakes:

(a) 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, as amended (the “Securities Act”);


(ii) to reflect in the prospectus any facts or events arising after the effective date of this 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 this registration statement. Notwithstanding the foregoing, any increase or decrease in the 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 Commission pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than a 20 percent change in the maximum aggregate offering price set forth in the “Calculation of Registration Fee” table in the effective registration statement; and


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

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

(b) That, for the purpose of determining any liability under the Securities Act, 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.


(c) 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.


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

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

(ii)    Each prospectus required to be filed pursuant to Rule 424(b)(2), (b)(5), or (b)(7) as part of this 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 shall be deemed to be part of and included in this 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 this registration statement relating to the securities in this 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 this registration statement or prospectus that is part
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of this registration statement or made in a document incorporated or deemed incorporated by reference into this registration statement or prospectus that is part of this 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 this registration statement or prospectus that was part of this registration statement or made in any such document immediately prior to such effective date.

(e)    That, for the purpose of determining liability of the Registrant under the Securities Act to any purchaser in the initial distribution of the securities, the

The undersigned Registrant hereby 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.

(f)    That, for purposes of determining any liability under the Securities Act, each filing of the Registrant’s annual report pursuant to Section 13(a) or 15(d) of the Exchange Act (and, where applicable, each filing of an employee benefit plan’s annual report pursuant to Section 15(d) of the Exchange Act) that is incorporated by reference in this registration statement shall be deemed to be a new registration statement relating to the securities offered therein and the offering of such securities at the time shall be deemed to be the initial bona fide offering thereof.
(g)    To supplement the prospectus, after the expiration of any warrant or right subscription period, to set forth the results of any warrant or right subscription offer, the transactions by the underwriters during the subscription period, the amount of unsubscribed securities to be purchased by the underwriters, and the terms of any subsequent reoffering thereof. If any public offering by the underwriters is to be made on terms differing from those set forth on the cover page of the prospectus, a post-effective amendment will be filed to set forth the terms of such offering.
(h)    That for purposes of determining any liability under the Securities Act, (i) the information omitted from the form of prospectus filed as part of this registration statement in reliance upon Rule 430A and contained in the form of prospectus filed by the Registrant pursuant to Rule 424(b)(l) or (4) or 497(h) under the Securities Act shall be deemed to be a part of this registration statement as of the time it was declared effective; and (ii) each post-effective amendment that contains a form of prospectus shall be deemed to be a new registration statement relating to the securities offered therein, and the offing of such securities at that time shall be deemed to be the initial bona fide offering thereof.
(i)    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 (the “Act”) in accordance with the rules and regulations prescribed by the Commission under Section 305(b)(2) of the Act.

Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers and controlling persons of the Registrant pursuant to the foregoing provisions described in Item 15, 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 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

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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 Act and will be governed by the final adjudication of such issue.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, as amended, the Registrantregistrant 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 Statementregistration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of The Woodlands, in the State of Texas, on August 6, 2021.

March 25, 2024.

Lexicon Pharmaceuticals, Inc.LEXICON PHARMACEUTICALS, INC.
By:

/s/ Lonnel Coats

Lonnel Coats
President and Chief Executive Officer


POWER OF ATTORNEY

Power of Attorney

Each person whose signature appears below appoints Lonnel Coats and Jeffrey L. Wade, and each of them, any of whom may act without the joinder of the other, as his or her true and lawful attorneys-in-fact and agents with full power of substitution and resubstitution, for him or her and in his or her name, place and stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) to this Registration Statement and any Registration Statement (including any amendment thereto) for this offering that is to be effective upon filing pursuant to Rule 462(b) under the Securities Act of 1933, as amended, and to file the same, with all exhibits thereto, and all other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents full power and authority to do and perform each and every act and thing requisite and necessary to be done, as fully to all intents and purposes as he might or would do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents or any of them or their or his substitute and substitutes, may lawfully do or cause to be done by virtue hereof.

PURSUANT TO THE REQUIREMENTS OF THE SECURITIES ACT OF

Pursuant to the requirements of the Securities Act of 1933, AS AMENDED, THIS REGISTRATION STATEMENT HAS BEEN SIGNED BELOW BY THE FOLLOWING PERSONS IN THE CAPACITIES AND ON THE DATES INDICATED BELOW.


as amended, this registration statement has been signed below by the following persons on behalf of the registrant in the capacities and on the dates indicated.

Signature

Title

Title

Date

/s/ Lonnel Coats

Lonnel Coats

President,

Chief Executive Officer and Director

(Principal Executive Officer)

August 6, 2021
Lonnel CoatsMarch 25, 2024

/s/ Jeffrey L. Wade

Jeffrey L. Wade

Executive Vice

President Corporate and Administrative Affairs and Chief Financial Officer (Principal

(Principal Financial Officer)

August 6, 2021
Jeffrey L. WadeMarch 25, 2024

/s/ James F. TessmerKristen L. Alexander

Kristen L. Alexander

Vice President, Finance and Accounting

(Principal Accounting Officer)

August 6, 2021
James F. TessmerMarch 25, 2024

/s/ Raymond Debbane

Raymond Debbane

Chairman of the Board of DirectorsAugust 6, 2021
Raymond DebbaneMarch 25, 2024

/s/ Philippe J. Amouval

Philippe J. Amouyal

DirectorAugust 6, 2021March 25, 2024
Philippe

/s/ Samuel L. Barker, Ph.D.

Samuel L. Barker, Ph.D.

DirectorMarch 25, 2024

/s/ Robert J. AmouyalLefkowitz, M.D.

Robert J. Lefkowitz, M.D.

DirectorMarch 25, 2024

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Signature

Title

Date

/s/ Samuel L. BarkerChristopher J. Sobecki

Christopher J. Sobecki

DirectorAugust 6, 2021
Samuel L. Barker, Ph.D.March 25, 2024

/s/ Robert J. LefkowitzDiane E. Sullivan

Diane E. Sullivan

DirectorAugust 6, 2021
Robert J. Lefkowitz, M.D.March 25, 2024
/s/ Alan S. NiesDirectorAugust 6, 2021
Alan S. Nies, M.D.
/s/ Frank P. PalantoniDirectorAugust 6, 2021
Frank P. Palantoni
/s/ Christopher J. SobeckiDirectorAugust 6, 2021
Christopher J. Sobecki

/s/ Judith L. Swain,

DirectorAugust 6, 2021
M.D.

Judith L. Swain, M.D.

DirectorMarch 25, 2024

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