EXHIBIT 3.4


                      WARRANT TO PURCHASE COMMON STOCK
                           OF APOLLO GENETICS, INC.



For valuable consideration, the receipt and sufficiency of which is hereby 
acknowledged, APOLLO GENETICS, INC. (the "Company") hereby grants unto 
NEUROSCIENCE PARTNERS LIMITED PARTNERSHIP (the "holder"), subject to the 
terms and conditions set forth herein, warrants (the "Warrants") to subscribe 
for and to have issued to it, subject to adjustment as provided for herein, 
150,000 shares of $.02 par value common stock ("Common Shares") in the 
capital of the Company, as the same may be reorganized or reclassified 
pursuant to any of the events set out herein, as fully paid and 
non-assessable, for an exercise price of $131,250 or $.875 per Common Share, 
(the "Exercise Price"). The Warrants may be exercised at any time in whole or 
from time to time in part, in accordance with and subject to the provisions 
hereof up to 5:00 p.m. (Boston time) on December 17, 2003 (the "Time of 
Expiry").  If any of the Warrants have not been exercised by the Time of 
Expiry all rights under any unexercised Warrants shall wholly cease and 
terminate and such Warrants shall be void and of no value or effect.

The Warrants are being granted pursuant to a Royalty Purchase Agreement 
between the Company and the holder dated the date hereof (the "Purchase 
Agreement"). In the event of any conflict or inconsistency between the 
provisions of the Warrants and the provisions of the Purchase Agreement, the 
Purchase Agreement shall govern.


1.    EXERCISE OF WARRANTS

      (a)   EXERCISE  The Warrants may be exercised by the holder in 
            accordance with the provisions hereof by surrendering to the Company
            at its principal office, in the City of Cambridge, Massachusetts,
            or at such other address in the United States as the holder may be
            notified in writing by the Company, at any time after the date 
            hereof up to the Time of Expiry this certificate, together with a
            Subscription Form, substantially in the form attached hereto as
            Schedule 1, duly completed and executed, and cash or a certified
            cheque, money order or bank draft payable to or to the order of 
            the Company for the amount equal to the Exercise Price per Common
            Share multiplied by the number of Common Shares subscribed for.

       (b)  PARTIAL EXERCISE  The holder may subscribe for and have issued to 
            it a number of Common Shares less than the total number the 
            holder is entitled to pursuant to this warrant certificate. In the
            event of any such subscription prior to the Expiry Time, the 
            holder shall be entitled to receive, without charge, a new warrant
            certificate (containing the same terms and conditions as this
            certificate) in respect of the balance of the Common Shares for
            which holder was entitled to subscribe pursuant to this warrant
            certificate and which were then not subscribed for.





       (c)  NET EXERCISE  Provided that the Common Shares are: (i) listed and
            posted for trading on a national securities exchange; or (ii)
            qualified for unlisted trading privileges on a trade reporting and
            quotation system for over-the-counter trading, the holder shall 
            have the right to require the Company to exchange the Warrants 
            (the "Exchange Option"), in whole or in part at any time or from
            time to time prior to the Expiry Time, for Common Shares as
            provided for in this Section.  Upon exercise of the Exchange
            Option, the Company shall deliver to the holder (without payment
            by the holder of any kind) the number of Common Shares calculated
            as follows:


                       Y(A-B)
                  X = --------
                          A

            where:        X = the number of Common Shares to be issued to the
                              holder upon the exercise of the Exchange Option.

                          Y = the maximum number of Common Shares issuable
                              pursuant to the Warrants immediately prior to 
                              the exercise of the Exchange Option, provided 
                              that if the holder requests exchange with 
                              respect only to part of the Warrants, this 
                              number shall be that number of Warrants for
                              which exchange has been requested.
 
                          A = the Current Market Price on the day immediately
                              preceding the receipt of the Warrant Certificate
                              and Subscription Form specifying that the holder
                              is exercising the Exchange Option.
 
                          B = the Exercise Price in effect immediately prior 
                              to the exercise of the Exchange Option.

     For the purposes of the Exchange Option, "Current Market Price" at any
     date, means the weighted average of the closing prices per Common Share
     for the 30 trading days immediately prior to such date at which the
     Common Shares have traded on: (i) the principal national securities
     exchange on which the Common Shares are listed and posted for trading;
     or (ii) if the Common Shares are not listed and posted for trading on a
     national securities exchange, on the trade reporting and quotation
     system for over-the-counter trading on which the Common Shares 
     are qualified for unlisted trading privileges.

     The Exchange Option may be exercised by the holder, in whole or in
     part at any time or from time to time, by surrending or delivering
     to the Company prior to the Expiry Time at the address specified in
     Section 1(a) hereof with the Subscription Form, duly completed and
     executed, specifying that the holder is exercising the Exchange Option
     to acquire the number of Common Shares then issuable upon such
     exchange pursuant to this Section.

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(d)   SHARE CERTIFICATES Within 15 days after the date on which the Company 
      receives a duly completed and executed Subscription Form (the "Exercise 
      Date"), the Company shall (without payment by the holder of any kind,
      other than as provided in Section 1(a) above) issue and deliver to the
      address specified by the holder, registered in such name or names as
      the holder may direct or if no such direction has been given, in the
      name of the holder, a certificate or certificates for the number of 
      Common Shares issuable hereunder as a result of the delivery of the 
      Subscription Form. Such exercise shall be deemed to have been effected 
      as of the close of business on the Exercise Date and at such time the 
      rights of the holder with respect to the Warrants which have been 
      exercised as such shall cease, and the person or persons in whose name
      or names any certificate or certificates for Common Shares shall then 
      be issuable upon such exercise or deemed exercise shall be deemed to 
      have become the holder or holders of record of the Common Shares 
      represented thereby.

(e)   FRACTIONAL SHARES No fractional shares shall be issued upon exercise of 
      the Warrants.

(f)   CORPORATE CHANGES If the Company shall be a party to any reorganization,
      merger, amalgamation, dissolution or sale of all or substantially all
      of its assets (an "Event"), whether or not the Company is the surviving
      entity, the number of Warrants shall be adjusted so as to apply to the
      number of securities to which the holder of that number of Common Shares 
      subject to the unexercised Warrants immediately prior
      to the Event would have been entitled by reason of such Event. If the
      number of securities to which the holder is entitled following an Event
      is greater than the number of unexercised Warrants immediately prior to
      the Event, then the Exercise Price per share in effect immediately prior
      to such Event shall be reduced by the reciprocal of the multiple required
      to be used to arrive at the new number of securities. If the number of
      securities to which the holder is entitled following an Event is
      less than the number of unexercied Warrants immediately prior to the
      Event, then the Exercise Price per share in effect immediately prior to
      such Event shall be increased by the reciprocal of the fraction required
      to be used to arrive at the new number of securities.

(g)   SUBDIVISION OR CONSOLIDATION OF SHARES In the event the Company shall 
      subdivide its outstanding Common Shares into a greater number of Common 
      Shares, the number of Common Shares that the holder shall thereafter be 
      entitled to subscribe for and have issued to it hereunder shall be 
      proportionately increased and the Exercise Price per share in effect 
      immediately prior to such subdivision shall be reduced by the reciprocal
      of the multiple used to arrive at the new number of Common Shares.
      Conversely, in the event the Company shall consolidate its outstanding
      Common Shares into a lesser number of Common Shares, the number of Common
      Shares that the holder shall thereafter be entitled to subscribe for and
      have issued to it hereunder shall be 

                                       3



      proportionately decreased and the Exercise Price per share in effect 
      immediately prior to such consolidation shall be increased by the 
      reciprocal of the fraction used to arrive at the new number of Common
      Shares.

(h)  STOCK DIVIDENDS OR DISTRIBUTIONS In the event the Company: (i) issues 
     Common Shares or securities exchangeable for or convertible into Common 
     Shares to all or substantially all the holders of the Common Shares as a 
     stock dividend; or (ii) makes a distribution on its outstanding Common
     Shares payable in Common Shares or securities exchangeable for or
     convertible into Common Shares, the number of Common Shares that the holder
     shall thereafter be entitled to subscribe for and have issued to it
     hereunder shall be increased in proportion to the increase in the number of
     outstanding Common Shares (on a fully diluted basis) as a result of the
     stock dividend or distribution and the Exercise Price per share in effect
     immediately prior to such stock dividend or distribution shall be reduced
     by the reciprocal of the multiple used to arrive at the new number of
     Common Shares.

(i)   OTHER DISTRIBUTIONS  In the event the Company makes a distribution (a 
      "Distribution") on its outstanding Common Shares payable in: (i) shares 
      of the Company of any class other than Common Shares; (ii) rights, 
      options or warrants to acquire shares or securities exchangeable for or 
      convertible into shares or property or other assets of the Company; 
      (iii) evidence of indebtedness; or (iv) any property or other assets of 
      the Company, the Exercise Price per share in effect immediately prior 
      to such Distribution shall be reduced by a fraction that is equal to 
      the ratio of the aggregate fair market value of the Company immediately 
      following the Distribution to the fair market value immediately prior 
      to the Distribution.

(j)   CHANGE OR RECLASSIFICATION OF SHARES  In the event the Company shall 
      change or reclassify its outstanding Common Shares into a different 
      class of securities, the Warrants shall be adjusted so as to apply to 
      the number of the successor class of securities to which the holder of 
      that number of Common Shares subject to the unexercised Warrants 
      immediately prior to the change or reclassification would have been 
      entitled to by reason of such change or reclassification. If the number 
      of securities to which the holder is entitled to subscribe for and have 
      issued to it hereunder following a change or reclassification is 
      greater than the number of unexercised Warrants immediately prior to 
      the change or reclassification, then the Exercise Price per share in 
      effect immediately prior to such change or reclassification shall be 
      reduced by the reciprocal of the multiple required to be used to arrive 
      at the new number of securities. If the number of securities to which 
      the holder is entitled to subscribe for and have issued to it hereunder 
      following a change or reclassification is less than the number of 
      unexercised Warrants immediately prior to the change or 
      reclassification, then the Exercise Price per share in effect 
      immediately prior to such change or reclassification shall be increased 
      by the reciprocal of the fraction required to be used to arrive at the 
      new number of securities.

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(k)   ADDITIONAL SUBSCRIPTIONS  If at any time the Company grants to its 
      shareholders the right to subscribe for and purchase pro rata 
      additional securities of the Company or of any other corporation or 
      entity, the Company shall grant to the holder the right to subscribe 
      for and purchase the same securities on the same terms and conditions 
      as being granted to its shareholders pro rata as if the holder was the 
      shareholder of that number of Common Shares subject to the unexercised 
      Warrants.

(l)   NOTICE OF ADJUSTMENT  Upon any adjustment of the number of Common 
      Shares and the Exercise Price per share subject to these Warrants then 
      and in each case the Company shall give written notice thereof to the 
      holder, which notice shall state the number of Common Shares or other 
      securities subject to the unexercised Warrants and the Exercise Price 
      per share resulting from such adjustment, and shall upon receipt of the 
      written request of the holder set forth in reasonable detail the method 
      of calculation and the facts upon which such calculation is based.

(m)   ADJUSTMENTS CUMULATIVE  The adjustments provided for herein are 
      cumulative and will: (i) in the case of adjustments to the Exercise 
      Price, be computed to the nearest one-tenth of one percent; (ii) in the 
      case of adjustments to the number of Common Shares which may be 
      subscribed for and purchased hereunder, be computed to two decimal 
      places and rounded up or down, as appropriate, to the nearest whole 
      number; and (iii) be made successively whenever an event referred to 
      herein occurs. For certainty, no adjustment in the Exercise Price is 
      required to be made unless such adjustment would result in a change of 
      at least one percent (1%) in the prevailing Exercise Price; provided, 
      however, that any adjustments which, except for the provisions of this 
      Subsection, would otherwise have been required to be made, will be carried
      forward and taken into account in any subsequent adjustments.

(n)   SHARES TO BE RESERVED  The Company will at all times keep available, 
      and reserve out of its authorized Common Shares, solely for the purpose 
      of issue upon the exercise of the Warrants, such number of Common 
      Shares as shall then be issuable upon the exercise or deemed exercise 
      of the Warrants. The Company covenants and agrees that all Common 
      Shares which shall be so issuable will, upon issuance, be duly authorized
      and issued as fully paid and non-assessable. The Company will take all 
      such actions as may be possible to ensure that all such Common Shares 
      may be so issued without violation of any applicable requirements of 
      any stock exchange upon which the Common Shares may be listed or in 
      respect of which the Common Shares are qualified for unlisted trading 
      privileges and without violation of any applicable law. The Company 
      acknowledges that the Common Shares issuable upon due exercise of the 
      warrants are subject to the Registration Rights Agreement between the 
      parties of even date herewith.

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2.   REPLACEMENT

Upon receipt of evidence satisfactory to the Company of the loss, theft, 
destruction or mutilation of this warrant certificate, the Company will issue 
to the holder a replacement certificate (containing the same terms and 
conditions as this certificate).

3.   EXPIRY DATE

The Warrants shall expire and all rights to subscribe for Common Shares 
hereunder shall cease and become null and void at the Time of Expiry.

4.   SATURDAYS, SUNDAYS AND HOLIDAYS

If any action is required to be taken pursuant hereto on or by a specified 
date which is a Saturday, Sunday or a civic or statutory holiday in Boston, 
Massachusetts or Toronto, Ontario, then such action shall be valid if taken 
on or by the next succeeding day that is not a Saturday, Sunday or a civic or 
statutory holiday in Boston, Massachusetts or Toronto, Ontario.

5.   GOVERNING LAW

This Agreement shall be governed by, and interpreted and enforced in 
accordance with, the laws in force in the Commonwealth of Massachusetts. The 
Parties irrevocably submit to the non-exclusive jurisdiction of the courts of 
the Commonwealth of Massachusetts with respect to any matter arising 
hereunder or related hereto.

6.   AMENDMENT

These Warrants and the terms hereof may be amended or supplemented only by a 
written agreement signed by the Company and the holder.

7.   SUCCESSORS

Subject to the terms hereof, these Warrants and the terms hereof shall enure 
to the benefit of and be binding upon the holder and the Company and their 
respective successors and assigns.

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IN WITNESS WHEREOF the Company has caused this certificate to be signed by 
its duly authorized officers.

DATED December 18, 1996.

                                   APOLLO GENETICS, INC.

                                   /s/ Katherine Gordon
                                   ---------------------------------------
                                   Name:  Katherine Gordon
                                   Title: President


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                                   SCHEDULE 1

                                Subscription Form

TO:  APOLLO GENETICS, INC. (the "Company")

RE:  Warrants to purchase 150,000 shares of $.02 par value common stock in the 
     capital of the Company dated December 17, 1996 (the "Warrants").

The undersigned holder hereby irrevocably elects to exercise ____ of the 
Warrants and hereby subscribes for ____ shares (or other property or 
securities contemplated in the Warrants) and herewith:

X / /  encloses cash or a certified cheque, money order or bank draft payable 
       to the order of the Company in payment of the Exercise Price therefor on
       the terms and conditions set out in the certificate representing the 
       Warrants (the "Warrant Certificate"); or

X / /  elects, pursuant to Section 1(c) of the Warrant Certificate, to exchange
       the Warrants for the Common Shares and, subject to the issuance to the 
       holder of a certificate for the warrants not being exchanged pursuant 
       hereto, surrenders the Warrant Certificate to the Company and all right,
       title and interest to the Warrants being exchanged hereby.

If any Warrants represented by this certificate are not being exercised or 
exchanged, a new warrant certificate is to be issued and delivered to the 
holder.

Terms not otherwise defined herein shall have the meanings assigned thereto 
in the Warrant Certificate.

DATED this ____ day of _______________, _____.

                                       [THE HOLDER]

                                       By: ____________________________________
                                       Name:
                                       Title:
DIRECTION AS TO REGISTRATION

Name of Registered Holder:      _______________________________________________

Address of Registered Holder:   _______________________________________________

                                _______________________________________________

DIRECTIONS AS TO DELIVERY

Address of Delivery             _______________________________________________

                                _______________________________________________

Attention:                      _______________________________________________