EXHIBIT 3.4

                              AMENDED AND RESTATED
                          CERTIFICATE OF INCORPORATION
                                       OF
                                 MEGABIOS CORP.


                                       I.

     The name of the Corporation is:

                                 MEGABIOS Corp.

                                      II.

     The address of the registered office of the Corporation in the State of
Delaware is 1013 Centre Road, City of Wilmington, County of New Castle, and the
name of the registered agent of the Corporation in the State of Delaware at such
address is Corporation Service Company.

                                      III.

     The purpose of the Corporation is to engage in any lawful act or activity
for which a corporation may be organized under the General Corporation Law of
the State of Delaware.

                                      IV.

     The Corporation is authorized to issue two classes of stock to be
designated, respectively, "Common Stock" and "Preferred Stock."  The total
number of shares which the corporation is authorized to issue is Forty Million
(40,000,000) shares.  Thirty Million (30,000,000) shares shall be Common Stock,
each having a par value of one tenth of one cent ($.001).  Ten Million
(10,000,000) shares shall be Preferred Stock, each having a par value of one
tenth of one cent ($.001).

     The Board of Directors is authorized to provide by resolution or
resolutions for the issuance of shares of stock of any class or of any series of
any class at any time and from time to time and, by filing a Certificate of
Designation in the manner prescribed under the laws of the State of Delaware, to
fix and amend the voting powers, full or limited, or no voting powers, and the
designations, preferences and relative, participating, optional or other special
rights, if any, and qualifications, limitations or restrictions thereof.  Unless
otherwise provided in any such resolution or resolutions, the number of shares
of stock of any such series to which such resolution or resolutions apply may be
increased (but not above the total number of authorized shares of the class) or
decreased (but not below the number of shares thereof then outstanding) by
filing a Certificate of Designation in the manner prescribed under the laws of
the State of Delaware.  In case the number of shares of any series shall be
decreased in accordance with the

 
foregoing sentence, the shares constituting such decrease shall resume the
status that they had prior to the adoption of the resolution originally fixing
the number of shares of such series.

     Shares of Common Stock and Preferred Stock may be issued from time to time
as the Board of Directors of the corporation shall determine and on such terms
and for such consideration as shall be fixed by the Board of Directors.

     No holder of any shares of stock of the Corporation of any class shall be
entitled as such, as a matter of right, to subscribe for or purchase any shares
of stock of the Corporation of any class, whether now or hereafter authorized or
whether issued for cash, property or services or as a dividend or otherwise, or
to subscribe for or purchase any obligations, bonds, notes, debentures, other
securities or stock convertible into shares of stock of the Corporation of any
class or carrying or evidencing any right to purchase shares of stock of any
class.

     Except as may be required by law, each holder of Common Stock shall have
one vote in respect of each share of Common Stock held by such person on all
matters voted upon by the stockholders.

                                       V.

     A.  For the management of the business and for the conduct of the affairs
of the Corporation, and in further definition, limitation and regulation of the
powers of the Corporation, of its directors and of its stockholders or any class
thereof, as the case may be, it is further provided that:

     (1) The management of the business and the conduct of the affairs of the
Corporation shall be vested in its Board of Directors.  The number of directors
which shall constitute the whole Board of Directors shall be fixed exclusively
by one or more resolutions adopted by the Board of Directors.

     (2) A majority of the whole Board of Directors shall constitute a quorum
for the transaction of business, and, except as otherwise provided in this
Restated Certificate of Incorporation or the Bylaws, the vote of a majority of
the directors present at a meeting at which a quorum is then present shall be
the act of the Board.  As used in this Restated Certificate of Incorporation,
the terms "whole Board" and "whole Board of Directors" are hereby exclusively
defined and limited to mean the total number of directors which the Corporation
would have if the Board had no vacancies.

     (3) Subject to the rights of the holders of any series of Preferred Stock
to elect additional directors under specified circumstances, following the
closing of the initial public offering pursuant to an effective registration
statement under the Securities Act of 1933, as amended, covering the offer and
sale of Common Stock to the public (the "Initial Public Offering"), the
directors shall be divided into three classes (to be designated as Class I,
Class II and Class III, respectively), as nearly equal in number as the then
total number of Directors constituting the whole Board of Directors permits,
with the terms of office of one class expiring each year.  Benjamin F. McGraw,
III and Frank J. Caufield are hereby named as Class I

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Directors to hold office for a term expiring at the annual meeting of
stockholders in 1998 and until their respective successors are duly elected and
qualified or until their respective earlier resignation or removal; A. Grant
Heidrich and Edward L. Erickson are hereby named as Class II Directors to hold
office for a term expiring at the annual meeting of stockholders in 1999 and
until their respective successors are duly elected and qualified or until their
earlier resignation or removal; Raju Kucherlapati and Russell C. Hirsch are
hereby named as Class III Directors to hold office for a term expiring at the
annual meeting of stockholders in 2000 and until their respective successors are
duly elected and qualified or until their respective earlier resignation or
removal.  Notwithstanding the foregoing, and except as otherwise required by
law, whenever the holders of any one or more series of Preferred Stock shall
have the right, voting separately as a class, to elect one or more Directors of
the Corporation, the terms of the Director or Directors elected by such holders
shall expire at the next succeeding annual meeting of stockholders.  Subject to
the foregoing, at each annual meeting of stockholders the successors to the
class of directors whose term shall then expire shall be elected to hold office
for a term expiring at the third succeeding annual meeting.  Notwithstanding the
foregoing, each director shall serve until his successor shall have been duly
elected and qualified, unless he or she shall resign, become disqualified,
disabled or shall otherwise be removed.  No decrease in the number of directors
constituting the Board of Directors shall shorten the term of any incumbent
director.

     (4) Subject to the rights of the holders of any series of Preferred Stock,
and notwithstanding the fact that some lesser percentage may be specified by
law, this Restated Certificate of Incorporation or the Bylaws, the Board of
Directors or any individual director may be removed from office at any time (i)
with cause by the affirmative vote of the holders of a majority of the voting
power of all the then-outstanding shares of voting stock of the Corporation,
entitled to vote at an election of directors (the "Voting Stock") or (ii)
without cause by the affirmative vote of the holders of at least sixty-six and
two-thirds percent (66 2/3%) of the voting power of all the then-outstanding
shares of the Voting Stock.  As used in this Restated Certificate of
Incorporation, the term "with cause" is hereby exclusively defined and limited
to mean commission of a felony or a finding by a court of competent jurisdiction
of liability for negligence, or misconduct, in the performance of the director's
duty to the Corporation in a matter of substantial importance to the
Corporation, where such adjudication is no longer subject to direct appeal.

     (5) Subject to the rights of the holders of any series of Preferred Stock,
any vacancies on the Board of Directors resulting from death, resignation,
disqualification, removal or other causes and any newly created directorships
resulting from any increase in the number of directors, shall, unless the Board
of Directors determines by resolution that any such vacancies or newly created
directorships shall be filled by the stockholders, except as otherwise provided
by law, be filled only by the affirmative vote of a majority of the directors
then in office, even though less than a quorum of the Board of Directors, and
not by the stockholders.  Any director elected in accordance with the preceding
sentence shall hold office for the remainder of the full term of the director
for which the vacancy was created or occurred and until such director's
successor shall have been elected and qualified.

     B.  (1)  Subject to paragraph (h) of Section 43 of the Bylaws, and
notwithstanding the fact that some lesser percentage may be specified law, the
Bylaws may be altered or

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amended or new Bylaws adopted by the affirmative vote of at least sixty-six and
two-thirds percent (66-2/3%) of the voting power of all of the then-outstanding
shares of the Voting Stock.  The Board of Directors shall also have the power to
adopt, amend, or repeal Bylaws.

     (2) The directors of the Corporation need not be elected by written ballot
unless the Bylaws so provide.

     (3) No action shall be taken by the stockholders of the Corporation except
at an annual or special meeting of stockholders called in accordance with the
Bylaws and following the closing of the Initial Public Offering no action shall
be taken by the stockholders by written consent.

     (4) Advance notice of stockholder nominations for the election of directors
and of business to be brought by stockholders before any meeting of the
stockholders of the Corporation shall be given in the manner provided in the
Bylaws of the Corporation.

     (5) Special meetings of the stockholders of the Corporation may be called,
for any purpose or purposes, by (i) the Chairman of the Board of Directors, (ii)
the President, (iii) the Board of Directors pursuant to a resolution adopted by
a majority of the total number of authorized directors (whether or not there
exist any vacancies in previously authorized directorships at the time any such
resolution is presented to the Board of Directors for adoption) or (iv) by the
holders of the shares entitled to cast not less that ten percent (10%) of the
votes at the meeting, and shall be held at such place, on such date, and at such
time as the Board of Directors shall fix.

                                      VI.

     A.  The Corporation may agree to the terms and conditions upon which any
director, officer, employee or agent accepts his office or position and in its
Bylaws, by contract or in any other manner may agree to indemnify and protect
any director, officer, employee or agent of the Corporation, or any person who
serves at the request of the Corporation as a director, officer, employee or
agent of another corporation, partnership, joint ventures, trust, employee
benefit plan or other enterprise, to the fullest extent permitted by the laws
(including, without limitation, the statutes, case law and principles of equity)
of the State of Delaware.  If the laws (including, without limitation, the
statutes, case law or principles of equity, as the case may be) of the State of
Delaware are amended or changed to permit or authorize broader rights of
indemnification to any of the persons referred to in the immediately preceding
sentence, then the Corporation shall be automatically authorized to agree to
indemnify such respective persons to the fullest extent permitted or authorized
by such law, as so amended or changed, without the need for amendment or
modification of this Article VI and without further action by the directors or
stockholders of the Corporation.

     B.   A director of the Corporation shall not be personally liable to the
Corporation or its stockholders for monetary damages for any breach of fiduciary
duty as a director, except for liability (i) for any breach of the director's
duty of loyalty to the Corporation or its stockholders, (ii) for acts or
omissions not in good faith or which involve intentional misconduct or a knowing

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violation of law, (iii) under Section 174 of the Delaware General Corporation
Law, or (iv) for any transaction from which the director derived an improper
personal benefit.  If the Delaware General Corporation Law is amended after
approval by the stockholders of this Article to authorize corporate action
further eliminating or limiting the personal liability of directors, then the
liability of a director shall be eliminated or limited to the fullest extent
permitted by the Delaware General Corporation Law, as so amended.

     C.  Any repeal or modification of this Article VI shall be prospective and
shall not affect the rights under this Article VI in effect at the time of the
alleged occurrence of any act or omission to act giving rise to liability or
indemnification.

                                      VII.

     Whenever a compromise or arrangement is proposed between this Corporation
and its creditors or any class of them and/or between this Corporation and its
stockholders or any class of them, any court of equitable jurisdiction within
the State of Delaware may, on the application in a summary way of this
Corporation or of any creditor or stockholder thereof or on the application of
any receivers appointed for this Corporation under the provisions of Section 291
of Title 8 of the Delaware Code or on the application of trustees in dissolution
or of nay receiver or receivers appointed for this Corporation under the
provisions of Section 279 of Title 8 of the Delaware Code order a meeting of the
creditors or class of creditors, and/or the stockholders or class of
stockholders of this Corporation, as the case may be, to be summoned in such
manner as the said court directs.  If a majority in number representing three-
fourths in value of the creditors or class of creditors, and/or of the
stockholders or class of stockholders of this Corporation, as the case may be,
agree to any compromise or arrangement and to any reorganization of this
Corporation as consequence of such compromise or arrangement, the said
compromise or arrangement and the said reorganization shall, if sanctioned by
the court to which the said application has been made, be binding on all the
creditors or class of creditors, or on all the stockholders or class of
stockholders, of this Corporation, as the case may be, and also on this
Corporation.

                                     VIII.

     A.  The Corporation reserves the right to amend, alter, change or repeal
any provision contained in this Restated Certificate of Incorporation, in the
manner now or hereafter prescribed by statute, except as provided in paragraph
B. of this Article VIII, and all rights conferred upon the stockholders herein
are granted subject to this reservation.

     B.  Notwithstanding any other provisions of this Restated Certificate of
Incorporation or any provision of law which might otherwise permit a lesser vote
or no vote, but in addition to any affirmative vote of the holders of any
particular class or series of the Voting Stock required by law, this Restated
Certificate of Incorporation or any Preferred Stock Designation, the affirmative
vote of the holders of at least sixty-six and two-thirds percent (66-2/3%) of
the voting power of all of the then-outstanding shares of the Voting Stock,
voting together as a single class, shall be required to alter, amend or repeal
Articles V, VI, and VIII.

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