Exhibit 10.1

                            STOCK PURCHASE AGREEMENT

BioCryst Pharmaceuticals, Inc.
2190 Parkway Lake Drive
Birmingham, AL  35244

The undersigned investors (each an "Investor" and collectively the "Investors"),
hereby confirm their agreement with you as follows:

1. This Stock Purchase Agreement (the "Agreement") is made as of the date set
forth below between BioCryst Pharmaceuticals, Inc., a Delaware corporation (the
"Company"), and the Investors listed on Exhibit A

2. The Company has authorized the sale and issuance of up to 3,571,667 shares
(the "Shares") of common stock of the Company, $0.01 par value per share (the
"Common Stock"), subject to adjustment by the Company's Board of Directors, to
certain investors in a registered direct offering (the "Offering").

3. The Company and the Investors, severally and not jointly, agree that the
Investors will purchase from the Company and the Company will issue and sell to
the Investors an aggregate of 1,666,667.00 shares, for a purchase price of $6.00
per share, or an aggregate purchase price of $10,000,002.00, pursuant to the
Terms and Conditions for Purchase of Shares attached hereto as Annex I and
incorporated herein by this reference as if fully set forth herein. Unless
otherwise requested by the Investors, certificates representing the Shares
purchased by the Investors will be registered in each Investor's name and
address as set forth below.

4. Each Investor represents that, except as set forth below, (a) it has had no
position, office or other material relationship within the past three years with
the Company or its affiliates, (b) neither it, nor any group of which it is a
member or to which it is related, beneficially owns (including the right to
acquire or vote) any securities of the Company and (c) it has no direct or
indirect affiliation or association with any NASD member. Exceptions:

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(If no exceptions, write "none." If left blank, response will be deemed to be
"none.")


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Please confirm that the foregoing correctly sets forth the agreement between us
by signing in the space provided below for that purpose.

                              Dated as of: February 17, 2004 (the "Execution
                              Date")

CADUCEUS PRIVATE INVESTMENTS
II, LP, by its General Partner OrbiMed Capital II LLC

By:      /s/ Eric A. Bittelman
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Name:    Eric A. Bittelman
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Title:
         --------------------------------------------
Address:
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CADUCEUS PRIVATE INVESTMENTS II (QP), LP,
by its General Partner OrbiMed Capital II LLC

By:      /s/ Eric A. Bittelman
         --------------------------------------------
Name:    Eric A. Bittelman
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Title:
         --------------------------------------------
Address:
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UBS Juniper Crossover Fund, L.L.C.,
by its Managing Member OrbiMed Advisors LLC

By:      /s/ Eric A. Bittelman
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Name:    Eric A. Bittelman
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Title:
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Address:
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AGREED AND ACCEPTED:
BIOCRYST PHARMACEUTICALS, INC.

By:      /s/ Michael A. Darwin
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Title:   Chief Financial Officer
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                                     ANNEX I

                   TERMS AND CONDITIONS FOR PURCHASE OF SHARES

      1. Authorization and Sale of the Shares; Registration. Subject to the
terms and conditions of this Agreement, the Company has authorized the sale of
the Shares. The Shares have been registered on a Form S-3, File No. 333-111226
(the "Registration Statement"), which registration statement has been declared
effective by the Securities and Exchange Commission (the "Commission") on
January 5, 2004, has remained effective since such date and is effective on the
date hereof.

      2. Agreement to Sell and Purchase the Shares; Subscription Date;
Additional Agreements.

            2.1 At the Closing (as defined in Section 3), the Company will sell
to the Investors, and the Investors, severally and not jointly, will purchase
from the Company, upon the terms and conditions hereinafter set forth, the
respective number of Shares set forth opposite each Investor's name on Exhibit A
hereto ("Exhibit A") at the purchase price set forth on such Exhibit A.

            2.2 The Company may enter into this same or a similar form of Stock
Purchase Agreement with certain other investors (the "Other Investors") and may
complete sales of Shares to them. (The Investors and the Other Investors are
hereinafter sometimes collectively referred to as the "Investors," and this
Agreement and the Stock Purchase Agreements executed by the Other Investors are
hereinafter sometimes collectively referred to as the "Agreements.")

            2.3 The Investors acknowledge that: (a) the Company has retained
Leerink Swann & Company as placement agent (in its capacity as placement agent
of the Shares, the "Placement Agent"); (b) the Company intends to pay the
Placement Agent a fee in respect of the sale of Shares to the Investors; and (c)
the offering of the Shares is not a firm commitment underwriting.

            2.4 (a) The Investors will have the right to appoint a member to the
Company's Board of Directors as of the Closing Date ("Investor Director"). So
long as the Investors in the aggregate continue to own not less than 830,000
shares of Common Stock (appropriately adjusted for stock splits, reverse stock
splits, stock dividends and the like), the Investor Director shall have a right
to serve on the Board of Directors for a period of eighteen (18) months from the
Closing Date and may resign from the Board of Directors at any time without
notice. The Investor Director may not be removed from the Board of Directors by
the Company without "Cause" as defined in subsection (b) below.

                  (b) For purposes of this Section 2.4, the following shall
constitute "Cause": (i) any action by the Investor Director constituting fraud
or embezzlement in the course of his tenure on the Board of Directors, (ii) any
conviction of the Investor Director of a felony which would materially and
adversely interfere with the Investor Director's ability to perform his or her
duties as a member of the Board of Directors; (iii) continued gross neglect or
willful refusal by the Investor Director to perform his or her duties hereunder
for a period of ten (10) days following notice to the Investor Director of such
inaction; or (iv) a material breach by the Investor Director of any other
material obligations under this Agreement or the Company's By-laws if such
breach is not curable or, if curable, is not cured within thirty (30) days after
written notice thereof by the Company to the Investor Director.


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            2.5 Prior to Closing, the Company shall provide the Investors with
an Opinion of Company's legal counsel, reasonably satisfactory to the Investors,
which states that (i) the transaction contemplated by this Agreement has been
duly authorized by the Company, and (ii) the issuance and sale of the Shares to
the Investors under this Agreement has been duly registered under the Securities
Act of 1933, as amended.

      3. Delivery of the Shares at Closing. The completion of the purchase and
sale of the Shares (the "Closing") shall occur at the offices of Holme Roberts &
Owen LLP, 1700 Lincoln Street, Suite 4100, Denver, Colorado 80203, at 10:00
o'clock A.M. E.S.T. on February 17, 2004 (the "Closing Date"), but in no event
earlier than such date and time as the escrow agent (as identified on Exhibit C)
shall have received all of the executed Stock Purchase Agreements. The executed
Stock Purchase Agreements and the purchase price transferred by the Investors
(jointly the "Escrowed Property") will be held by the Escrow Agent until the
Closing is confirmed by the Company and Placement Agent. If the Closing does not
occur, the funds will be returned to the Investors. All wires should be sent to
Mintz Levin Cohn Ferris Glovsky and Popeo PC, as Escrow Agent, Fleet Bank of
Massachusetts, N.A., Malden MA 02148, ABA#011000138, Account Name: Mintz Levin
Cohn Ferris Glovsky and Popeo PC IOLTA Account, Account Number 534-66888,
Reference: Leerink Swann: 22437-045. At the Closing, upon written instruction of
the Company and the Placement Agent, the escrow agent shall release the Escrowed
Property (as defined on Exhibit C) to the Company and the Company shall arrange
delivery to the Investors one or more stock certificates representing the number
of Shares set forth on Exhibit A hereto, each such certificate to be registered
in the name of the Investors or, if so indicated on the Stock Certificate
Questionnaire attached hereto as Exhibit C, in the name of a nominee designated
by the Investors. Such stock certificates shall be unlegended and free of any
resale restrictions.

      The Company's obligation to issue the Shares to the Investors shall be
subject to the following conditions, any one or more of which may be waived by
the Company: (a) receipt by the Company of the purchase price for the Shares
being purchased hereunder as set forth on Exhibit A hereto; and (b) the accuracy
of the representations and warranties made by the Investors and the fulfillment
of those undertakings of the Investors to be fulfilled prior to the Closing.

      Each Investor's obligation to purchase the Shares shall be subject to the
following conditions, any one or more of which may be waived by the Investor:
(a) trading in the Common Stock shall not have been suspended by the Commission
(except for any suspension of trading of limited duration agreed to by the
Company, which suspension shall be terminated prior to the Closing Date); (b) no
stop order suspending the effectively of the Registration Statement shall have
been issued and no proceedings for that purpose shall have been initiated or
threatened by the Commission; and (c) receipt of a satisfactory legal opinion
from the Company's legal counsel pursuant to Section 2.5 of this Agreement. The
Investor's obligations are expressly not conditioned on the purchase by any or
all of the other Investors, if any, of the Shares that they have agreed to
purchase from the Company.

      4. Representations, Warranties and Covenants of the Company. Except as
otherwise described in the Company's filings with the Commission since December
31, 2002, including, without limitation, the Registration Statement (the
"Commission Documents"), in the Company's press releases since December 31,
2002, and in the certain operational, managerial and other information regarding
the Company (the "Proprietary Information") disclosed by the Company to the
Investors in contemplation of this offering, including the documents
incorporated by reference therein (the Commission Documents, press releases and
the Proprietary Information are collectively referred to herein as the


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"Company Information"), which qualify the following representations and
warranties in their entirety, the Company hereby represents and warrants to, and
covenants with, the Investors, as follows:

            4.1 Organization, Good Standing and Qualification. The Company is a
corporation duly organized, validly existing and in good standing under the laws
of the State of Delaware and has full corporate power and lawful authority to
conduct its business as described in its Company Information. The Company is
duly qualified to do business as a foreign corporation and is in good standing
in each jurisdiction in which the nature of the business conducted or as
proposed to be conducted in its Company Information, by it or the properties
owned, leased or operated by it, makes such qualification or licensing necessary
and where the failure to be so qualified or licensed would have a material
adverse effect upon the business, properties or financial condition of the
Company ("Material Adverse Effect").

            4.2 Capitalization and Voting Rights. The authorized, issued and
outstanding capital stock of the Company is as set forth in its Commission
Documents as of the date thereof; all issued and outstanding shares of capital
stock of the Company are validly issued, fully paid and nonassessable. Except as
set forth in the Company Information and except for shares reserved for issuance
pursuant to employee and consultant benefit and option plans within the limits
specified therein, there are no outstanding options, warrants, agreements,
commitments, convertible securities, preemptive rights or other rights to
subscribe for or to purchase any shares of capital stock of the Company nor are
there any agreements, promises or commitments to issue any of the foregoing.
Except as set forth in the Company's SEC filings, in this Agreement and as
otherwise required by law, there are no restrictions upon the voting or transfer
of the Shares pursuant to the Company's Certificate of Incorporation, as
amended, (the "Certificate of Incorporation"), By-laws or other governing
documents or any agreement or other instruments to which the Company is a party
or by which the Company is bound.

            4.3 Authorization; Enforceability. The Company has all corporate
right, power and authority to enter into this Agreement and to consummate the
transactions contemplated hereby. All corporate action on the part of the
Company, its directors and stockholders necessary for the authorization,
execution, delivery and performance of this Agreement by the Company, the
authorization, sale, issuance and delivery of the Shares and the performance of
the Company's obligations hereunder has been taken. This Agreement has been duly
executed and delivered by the Company and constitutes a legal, valid and binding
obligation of the Company, enforceable against the Company in accordance with
its terms, subject to laws of general application relating to bankruptcy,
insolvency and the relief of debtors and rules of law governing specific
performance, injunctive relief or other equitable remedies, and to limitations
of public policy. The Shares have been duly and validly authorized and, upon the
issuance and delivery thereof and payment therefor as contemplated by this
Agreement, will be free and clear of liens other than liens caused by the
Investors, duly and validly authorized and issued, fully paid and nonassessable.
The issuance and sale of the Shares contemplated hereby will not give rise to
any preemptive rights or rights of first refusal on behalf of any person.

            4.4 No Conflict; Governmental Consents.

                  (a) The execution and delivery by the Company of this
Agreement, the consummation of the transactions contemplated hereby and the
offer and sale of the Shares will not result in the violation of any material
law, statute, rule, regulation, order, writ, injunction, judgment or decree of
any court or governmental authority to or by which the


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Company is bound, or of any provision of the Certificate of Incorporation or
By-laws of the Company, and will not conflict with, or result in a breach or
violation of, any of the terms or provisions of, or constitute (with due notice
or lapse of time or both) a default under, any lease, loan agreement, mortgage,
security agreement, trust indenture or other agreement or instrument to which
the Company is a party or by which it is bound or to which any of its properties
or assets is subject, where such conflict, breach or default is likely to result
in a Material Adverse Effect, nor result in the creation or imposition of any
lien upon any of the material properties or assets of the Company.

                  (b) No consent, waiver, approval, authorization or other order
of any governmental authority is required to be obtained by the Company in
connection with the authorization, execution and delivery of this Agreement or
with the authorization, issuance and sale of the Shares, except such filings as
may be required to be made, and which shall have been made at or prior to the
required time, with the SEC, the NASD and The Nasdaq Stock Market, Inc.
("Nasdaq"), and with any state or foreign blue sky or securities regulatory
authority.

            4.5 Licenses. The Company has all licenses, permits and other
governmental authorizations currently required for the conduct of its business
or ownership of properties and is in all material respects complying therewith,
except for any licenses, permits or other governmental authorizations, the lack
of which would not likely result in a Material Adverse Effect.

            4.6 Litigation. The Company knows of no pending or threatened legal
or governmental proceedings against the Company which would likely result in a
Material Adverse Effect.

            4.7 Accuracy of Reports. All reports required to be filed by the
Company within the three years prior to the date of this Agreement under the
Securities Exchange Act of 1934, as amended, (the "Exchange Act"), have been
duly and timely filed with the SEC, complied at the time of filing in all
material respects with the requirements of their respective forms and, were
complete and correct in all material respects as of the dates at which the
information was furnished, and contained (as of such dates) no untrue statement
of a material fact or omitted to state a material fact necessary in order to
make the statements contained therein, in light of the circumstances under which
they were made, not misleading.

            4.8 Investment Company. The Company is not an "investment company"
within the meaning of such term under the Investment Company Act of 1940, as
amended, and the rules and regulations of the SEC thereunder.

            4.9 Listing. The Company has filed a Notification Form: Listing of
Additional Shares with the Nasdaq Stock Market and hereby represents and
warrants to the Placement Agent and the Investors that it will take any other
necessary action in accordance with the rules of the Nasdaq Stock Market to
enable the Shares to trade on the Nasdaq Stock Market.

            4.10 No Material Adverse Change. Except as disclosed in the Company
Information, since the filing of the Company's most recent Quarterly Report on
Form 10-Q, (i) there has not been any Material Adverse Effect, and (ii) there
has been no event or condition of any character that would likely result in a
Material Adverse Effect.

            4.11 Financial Statements. The financial statements included in the
Company's most recent Annual Report on Form 10-K, for the fiscal year ended
December


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31, 2002, and all other reports filed by the Company pursuant to the Exchange
Act since the filing of such Annual Report on Form 10-K and prior to the date
hereof (collectively, the "SEC Filings") present fairly and accurately in all
material respects the financial position of the Company as of the dates shown
and its results of operations and cash flows for the periods shown, and such
financial statements have been prepared in conformity with generally accepted
accounting principles applied on a consistent basis. Except as set forth in the
financial statements of the Company included in the SEC Filings filed prior to
the date hereof, to the best of the Company's knowledge, the Company has no
liabilities, contingent or otherwise, except those which individually or in the
aggregate are not material to the financial condition or operating results of
the Company.

            4.12 Compliance with Laws. The Company is in compliance with all
applicable Nasdaq continued listing requirements. There are no proceedings
pending or to the Company's knowledge threatened against the Company relating to
the continued listing of the Company's Common Stock on the Nasdaq Stock Market
and the Company has not received any notice of, nor to the knowledge of the
Company is there any basis for, the delisting of the Common Stock from the
Nasdaq Stock Market.

            4.13 Sarbanes-Oxley Act. The Company is in substantial compliance
with the applicable provisions of the Sarbanes-Oxley Act of 2002 (the
"Sarbanes-Oxley Act"), and the rules and regulations promulgated thereunder,
that are effective and intends to comply substantially with other applicable
provisions of the Sarbanes-Oxley Act, and the rules and regulations promulgated
thereunder, upon the effectiveness of such provisions.

            4.14 Disclosure. To the best of the Company's knowledge, neither
this Agreement nor any other documents, certificates or instruments furnished to
the Investors by or on behalf of the Company or any Subsidiary in connection
with the transactions contemplated by this Agreement, taken as a whole together
with the Company Information, contain any untrue statement of a material fact or
omit to state a material fact necessary in order to make the statements made
herein or therein, in the light of the circumstances under which they were made
herein or therein, not misleading.

            4.15 Registration Statement; Effectiveness. The sale and issuance by
the Company of the Shares have been validly registered pursuant to the
Registration Statement and such Shares of Common Stock will be issued without a
restrictive legend.

      5. Representations, Warranties and Covenants of the Investors.

            5.1 Each Investor individually represents and warrants to, and
covenants with, the Company that: (i) the Investor is knowledgeable,
sophisticated and experienced in making, and is qualified to make decisions with
respect to, investments in shares presenting an investment decision like that
involved in the purchase of the Shares, including investments in Shares issued
by the Company and investments in comparable companies, and has requested,
received, reviewed and considered all information it deemed relevant in making
an informed decision to purchase the Shares; (ii) the Investor is acquiring the
number of Shares set forth on Exhibit A hereto in the ordinary course of its
business and for its own account for investment only and with no present
intention of distributing any of such Shares or any arrangement or understanding
with any other persons regarding the distribution of such Shares (this
representation and warranty not limiting such Investor's right to sell the
Shares pursuant to the Registration Statement or otherwise in compliance with
applicable federal and state securities laws); (iii) the Investor will not,
directly or indirectly, offer, sell, pledge, transfer or otherwise dispose of
(or solicit any offers to buy, purchase or otherwise acquire or take a pledge
of) any of the Shares except in compliance with the Securities Act, applicable


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state securities laws and the respective rules and regulations promulgated
thereunder; and (iv) the Investor, after giving effect to the transactions
contemplated hereby, will not, either individually or with a group (as defined
in Section 13(d)(3) of the Exchange Act), be the beneficial owner of 15% or more
of the Company's outstanding Common Stock. For purposes of this Section 5.1,
beneficial ownership shall be determined pursuant to Rule 13d-3 under the
Exchange Act.

            5.2 Each Investor individually acknowledges, represents and agrees
that no action has been or will be taken in any jurisdiction outside the United
States by the Company or the Placement Agent that would permit an offering of
the Shares, or possession or distribution of offering materials in connection
with the issue of the Shares, in any jurisdiction outside the United States
where action for that purpose is required. Each Investor outside the United
States will comply with all applicable laws and regulations in each foreign
jurisdiction in which it purchases, offers, sells or delivers Shares or has in
its possession or distributes any offering material, in all cases at its own
expense. The Placement Agent is not authorized to make any representation or use
any information in connection with the issue, placement, purchase and sale of
the Shares.

            5.3 Each Investor hereby covenants with the Company not to make any
sale of the Shares without effectively causing the prospectus delivery
requirement under the Securities Act to be satisfied. Each Investor acknowledges
that there may occasionally be times when the Company, based on the advice of
its counsel, determines that it must suspend the use of the Prospectus forming a
part of the Registration Statement until such time as an amendment to the
Registration Statement has been filed by the Company and declared effective by
the Commission or until the Company has amended or supplemented such Prospectus.

            5.4 Each Investor further represents and warrants to, and covenants
with, the Company that (i) the Investor has full right, power, authority and
capacity to enter into this Agreement and to consummate the transactions
contemplated hereby and has taken all necessary action to authorize the
execution, delivery and performance of this Agreement, and (ii) this Agreement
constitutes a valid and binding obligation of the Investor enforceable against
the Investor in accordance with its terms, except as enforceability may be
limited by applicable bankruptcy, insolvency, reorganization, moratorium or
similar laws affecting creditors' and contracting parties' rights generally and
except as enforceability may be subject to general principles of equity
(regardless of whether such enforceability is considered in a proceeding in
equity or at law) and except as the indemnification agreements of the Investors
herein may be legally unenforceable.

            5.5 Each Investor understands that nothing in this Agreement or any
other materials presented to the Investor in connection with the purchase and
sale of the Shares constitutes legal, tax or investment advice. Each Investor
has consulted such legal, tax and investment advisors as it, in its sole
discretion, has deemed necessary or appropriate in connection with its purchase
of Shares.

      6. Survival of Representations, Warranties and Agreements. Notwithstanding
any investigation made by any party to this Agreement or by the Placement Agent,
all covenants, agreements, representations and warranties made by the Company
and each of the Investors herein shall survive the execution of this Agreement,
the delivery to the Investor of the Shares being purchased and the payment
therefor.

      7. Notices. All notices, requests, consents and other communications
hereunder shall be in writing, shall be mailed (A) if within domestic United
States by first-class


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registered or certified airmail, or nationally recognized overnight express
courier, postage prepaid, or by facsimile, or (B) if delivered from outside the
United States, by International Federal Express or facsimile, and shall be
deemed given (i) if delivered by first-class registered or certified mail
domestic, three business days after so mailed, (ii) if delivered by nationally
recognized overnight carrier, one (1) business day after so mailed, (iii) if
delivered by International Federal Express, two (2) business days after so
mailed, (iv) if delivered by facsimile, upon electric confirmation of receipt
and shall be delivered as addressed as follows:

                  (a) if to the Company, to:

                      BioCryst Pharmaceuticals, Inc.
                      2190 Parkway Lake Drive
                      Birmingham, AL  35244

                      Attn:  Chief Executive Officer
                      Phone:  (205) 444-4600
                      Telecopy:  (205) 444-4640

                  (b) with a copy mailed to:

                      Holme Roberts & Owen LLP
                      1700 Lincoln Street, Suite 4100
                      Denver, CO  80203

                      Attn:  Richard R. Plumridge, Esq.
                      Phone:  (303) 861-7000
                      Telecopy:  (303) 866-0200

                  (c) if to the Investors, at their addresses on the Signature
Page hereto, or at such other address or addresses as may have been furnished to
the Company in writing.

      8. Changes. This Agreement may not be modified or amended except pursuant
to an instrument in writing signed by the Company and the Investors.

      9. Headings. The headings of the various sections of this Agreement have
been inserted for convenience of reference only and shall not be deemed to be
part of this Agreement.

      10. Severability. In case any provision contained in this Agreement should
be invalid, illegal or unenforceable in any respect, the validity, legality and
enforceability of the remaining provisions contained herein shall not in any way
be affected or impaired thereby.

      11. Governing Law. This Agreement shall be governed by, and construed in
accordance with, the internal laws of the State of New York, without giving
effect to the principles of conflicts of law.

      12. Counterparts. This Agreement may be executed in two or more
counterparts, each of which shall constitute an original, but all of which, when
taken together, shall constitute but one instrument, and shall become effective
when one or more counterparts have been signed by each party hereto and
delivered to the other parties.


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      13. Confidential Disclosure Agreement. Notwithstanding any provision of
this Agreement to the contrary, any confidential disclosure agreement previously
executed by the Company and the Investors in connection with the transactions
contemplated by this Agreement shall remain in full force and effect in
accordance with its terms following the execution of this Agreement and the
consummation of the transactions contemplated hereby.

      14. Third Party Beneficiary. Except as provided on Exhibit C, nothing in
this Agreement shall create or be deemed to create any rights in any person or
entity not a party to this Agreement.

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