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                                                                       EXHIBIT 3


                AMENDED AND RESTATED CERTIFICATE OF INCORPORATION
                         OF EPOCH PHARMACEUTICALS, INC.,
                             a Delaware corporation


               The undersigned, Sanford S. Zweifach, hereby certifies that:

               ONE: He is the President and Secretary of Epoch Pharmaceuticals,
Inc., a Delaware corporation (the "Corporation").

               TWO: The Certificate of Incorporation of the Corporation was
originally filed with the Secretary of State of Delaware on August 14, 1985
under its original name, "Microprobe Corporation."

               THREE: The Certificate of Incorporation of the Corporation shall
be amended and restated to read in full as follows:


                                "ARTICLE 1. NAME

        The name of this Corporation is Epoch Pharmaceuticals, Inc.


                     ARTICLE 2. REGISTERED OFFICE AND AGENT

        The address of the registered office of the Corporation is Corporation
Trust Center, 1209 Orange Street, Wilmington, County of New Castle, State of
Delaware 19801, and the name of its registered agent at such address is The
Corporation Trust Company.


                               ARTICLE 3. PURPOSES

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


                                ARTICLE 4. SHARES

        The total number of shares of stock which the Corporation shall have the
authority to issue is sixty million (60,000,000) shares, consisting of a class
of ten million (10,000,000) shares of Preferred Stock, par value $.01 per share,
and a class of fifty million (50,000,000) shares of Common Stock, par value $.01
per share (the Preferred Stock, par value $.01 per share, being herein referred
to as 'Preferred Stock'; and the Common Stock, par value $.01 per share, being
herein referred to as 'Common Stock'). The Board of Directors is expressly
authorized to provide for the issuance of the shares of Preferred Stock in one
or more series and, by filing a Certificate pursuant to the applicable law of
the State of Delaware, to establish from time to time the number of shares to be
included in each series, and to fix the designations, powers, preferences and
relative, participation, optional or other special rights, if any, of the shares
of each such series and the qualifications, limitations and restrictions
thereof, if any, with respect to each such series of Preferred Stock.

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                               ARTICLE 5. BY-LAWS

        The Board of Directors shall have the power to adopt, amend or repeal
the By-laws of the Corporation, subject to the power of the stockholders to
amend or repeal such By-laws. The stockholders shall also have the power to
adopt, amend or repeal the By-laws of the Corporation.


                        ARTICLE 6. ELECTION OF DIRECTORS


        Written ballots are not required in the election of Directors.


                          ARTICLE 7. PREEMPTIVE RIGHTS


        No preemptive rights shall exist with respect to shares of stock or
securities convertible into shares of stock of the Corporation


                          ARTICLE 8. CUMULATIVE VOTING

        The right to cumulate votes in the election of Directors shall not exist
with respect to shares of stock of the Corporation.


                    ARTICLE 9. AMENDMENTS TO CERTIFICATE OF INCORPORATION

        The Corporation reserves the right to amend or repeal, by the
affirmative vote of the holders of a majority of the shares entitled to vote
thereon, any of the provisions contained in this Certificate of Incorporation,
and the rights of the stockholders of the Corporation are granted subject to the
reservation.


                  ARTICLE 10. LIMITATION OF DIRECTOR LIABILITY

        To the full extent that the Delaware General Corporation Law, as it
exists on the date hereof or may hereafter be amended, permits the limitation or
elimination of the liability of directors, a Director of the Corporation shall
not be liable to the Corporation or its stockholders for monetary damages. Any
amendment to or repeal of this Article 10 shall not adversely affect any right
or protection of a Director of the Corporation for or with respect to any acts
or omissions of such Director occurring prior to such amendment or repeal.

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                                ARTICLE 11. SECTION 203

        The Corporation expressly elects to be governed by Section 203 of the
General Corporation Law of the State of Delaware."

               FOUR: The foregoing Amended and Restated Certificate of
Incorporation has been duly adopted by the Corporation's Board of Directors and
stockholders in accordance with the applicable provisions of Sections 242 and
245 of the General Corporation Law of the State of Delaware.

               IN WITNESS WHEREOF, the undersigned has executed this certificate
on June __, 1998.

                                            EPOCH PHARMACEUTICALS, INC.


                                            By:
                                                  ------------------------------
                                                  Sanford S. Zweifach
                                                  President and Secretary