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                                                                     Exhibit 3.2



                   CERTIFICATE OF DESIGNATION, PREFERENCES AND
             RIGHTS OF SERIES A JUNIOR PARTICIPATING PREFERRED STOCK

                                       of

                               CELL PATHWAYS, INC.

             Pursuant to Section 151 of the General Corporation Law
                            of the State of Delaware


         We, Robert J. Towarnicki, Chief Executive Officer, and Richard H. Troy,
Secretary, of Cell Pathways, Inc., a corporation organized and existing under
the General Corporation Law of the State of Delaware, in accordance with the
provisions of Section 103 thereof, DO HEREBY CERTIFY:

         That pursuant to the authority conferred upon the Board of Directors by
the Certificate of Incorporation of the said Corporation, the said Board of
Directors on December 3, 1998, adopted the following resolution creating a
series of 600,000 shares of Preferred Stock designated as Series A Junior
Participating Preferred Stock:

         RESOLVED, that pursuant to the authority vested in the Board of
         Directors of this Corporation in accordance with the provisions of its
         Certificate of Incorporation, a series of Preferred Stock of the
         Corporation be and it hereby is created, and that the designation and
         amount thereof and the voting powers, preferences and relative,
         participating, optional and other special rights of the shares of such
         series, and the qualifications, limitations or restrictions thereof are
         as follows:

         Section 1. Designation and Amount. The shares of such series shall be
designated as "Series A Junior Participating Preferred Stock" and the number of
shares constituting such series shall be 600,000.

         Section 2. Dividends and Distributions.

         (A) Subject to the prior and superior rights of the holders of any
shares of any series of Preferred Stock ranking prior and superior to the shares
of Series A Junior Participating Preferred Stock with respect to dividends, the
holders of shares of Series A Junior Participating Preferred Stock shall be
entitled to receive, when, as and if declared by the Board of Directors out of
funds legally available for the purpose, quarterly dividends payable in cash on
the first day of March, June, September and December in each year (each such
date being referred to herein as a "Quarterly Dividend Payment Date"),
commencing on the first Quarterly Dividend Payment Date after the first issuance
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of a share or fraction of a share of Series A Junior Participating Preferred
Stock, in an amount per share (rounded to the nearest cent) equal to the greater
of (a) $1.00 or (b) subject to the provision for adjustment hereinafter set
forth, 100 times the aggregate per share amount of all cash dividends, and 100
times the aggregate per share amount (payable in kind) of all non-cash dividends
or other distributions other than a dividend payable in shares of Common Stock
or a subdivision of the outstanding shares of Common Stock (by reclassification
or otherwise), declared on the Common Stock, par value $.01 per share, of the
Corporation (the "Common Stock") since the immediately preceding Quarterly
Dividend Payment Date, or, with respect to the first Quarterly Dividend Payment
Date, since the first issuance of any share or fraction of a share of Series A
Junior Participating Preferred Stock. In the event the Corporation shall at any
time after December 3, 1998 (the "Rights Declaration Date") (i) declare any
dividend on Common Stock payable in shares of Common Stock, (ii) subdivide the
outstanding Common Stock, or (iii) combine the outstanding Common Stock into a
smaller number of shares, then in each such case the amount to which holders of
shares of Series A Junior Participating Preferred Stock were entitled
immediately prior to such event under clause (b) of the preceding sentence shall
be adjusted by multiplying such amount by a fraction the numerator of which is
the number of shares of Common Stock outstanding immediately after such event
and the denominator of which is the number of shares of Common Stock that were
outstanding immediately prior to such event.

         (B) The Corporation shall declare a dividend or distribution on the
Series A Junior Participating Preferred Stock as provided in Paragraph (A) above
immediately after it declares a dividend or distribution on the Common Stock
(other than a dividend payable in shares of Common Stock); provided that, in the
event no dividend or distribution shall have been declared on the Common Stock
during the period between any Quarterly Dividend Payment Date and the next
subsequent Quarterly Dividend Payment Date, a dividend of $1.00 per share on the
Series A Junior Participating Preferred Stock shall nevertheless be payable on
such subsequent Quarterly Dividend Payment Date.

         (C) Dividends shall begin to accrue and be cumulative on outstanding
shares of Series A Junior Participating Preferred Stock from the Quarterly
Dividend Payment Date next preceding the date of issue of such shares of Series
A Junior Participating Preferred Stock, unless the date of issue of such shares
is prior to the record date for the first Quarterly Dividend Payment Date, in
which case dividends on such shares shall begin to accrue from the date of issue
of such shares, or unless the date of issue is a Quarterly Dividend Payment Date
or is a date after the record date for the determination of holders of shares of
Series A Junior Participating Preferred Stock entitled to receive a quarterly
dividend and before such Quarterly Dividend Payment Date, in either of which
events such dividends shall begin to accrue and be cumulative from such
Quarterly Dividend Payment Date. Accrued but unpaid dividends shall not bear
interest. Dividends paid on the shares of Series A Junior Participating
Preferred Stock in an amount less than the total amount of such dividends at the
time accrued and payable on such shares shall be allocated pro rata on a
share-by-share basis among all such shares at the time outstanding. 
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The Board of Directors may fix a record date for the determination of holders of
shares of Series A Junior Participating Preferred Stock entitled to receive
payment of a dividend or distribution declared thereon, which record date shall
be no more than 30 days prior to the date fixed for the payment thereof.

         Section 3. Voting Rights. The holders of shares of Series A Junior
Participating Preferred Stock shall have the following voting rights:

         (A) Subject to the provision for adjustment hereinafter set forth, each
share of Series A Junior Participating Preferred Stock shall entitle the holder
thereof to 100 votes on all matters submitted to a vote of the stockholders of
the Corporation. In the event the Corporation shall at any time after the Rights
Declaration Date (i) declare any dividend on Common Stock payable in shares of
Common Stock, (ii) subdivide the outstanding Common Stock, or (iii) combine the
outstanding Common Stock into a smaller number of shares, then in each such case
the number of votes per share to which holders of shares of Series A Junior
Participating Preferred Stock were entitled immediately prior to such event
shall be adjusted by multiplying such number by a fraction the numerator of
which is the number of shares of Common Stock outstanding immediately after such
event and the denominator of which is the number of shares of Common Stock that
were outstanding immediately prior to such event.

         (B) Except as otherwise provided herein or by law, the holders of
shares of Series A Junior Participating Preferred Stock and the holders of
shares of Common Stock shall vote together as one class on all matters submitted
to a vote of stockholders of the Corporation.

         (C)  (i)   If at any time dividends on any Series A Junior
         Participating Preferred Stock shall be in arrears in an amount equal to
         six (6) quarterly dividends thereon, the occurrence of such contingency
         shall mark the beginning of a period (herein called a "default period")
         which shall extend until such time when all accrued and unpaid
         dividends for all previous quarterly dividend periods and for the
         current quarterly dividend period on all shares of Series A Junior
         Participating Preferred Stock then outstanding shall have been declared
         and paid or set apart for payment. During each default period, all
         holders of Preferred Stock (including holders of the Series A Junior
         Participating Preferred Stock) with dividends in arrears in an amount
         equal to six (6) quarterly dividends thereon, voting as a class,
         irrespective of series, shall have the right to elect two (2)
         directors.

              (ii)  During any default period, such voting right of the holders
         of Series A Junior Participating Preferred Stock may be exercised
         initially at a special meeting called pursuant to subparagraph (iii) of
         this Section 3(C) or at any annual meeting of stockholders, and
         thereafter at annual meetings of stockholders, provided that neither
         such voting right nor the right of the holders of any other series of
         Preferred Stock, if any, to increase, in certain cases, the authorized
         number of directors shall be exercised unless the holders of ten
         percent (10%) in number of shares of Preferred Stock outstanding shall
         be present in person or by 
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         proxy. The absence of a quorum of the holders of Common Stock shall not
         affect the exercise by the holders of Preferred Stock of such voting
         right. At any meeting at which the holders of Preferred Stock shall
         exercise such voting right initially during an existing default period,
         they shall have the right, voting as a class, to elect directors to
         fill such vacancies, if any, in the Board of Directors as may then
         exist up to two (2) directors or, if such right is exercised at an
         annual meeting, to elect two (2) directors. If the number which may be
         so elected at any special meeting does not amount to the required
         number, the holders of the Preferred Stock shall have the right to make
         such increase in the number of directors as shall be necessary to
         permit the election by them of the required number. After the holders
         of the Preferred Stock shall have exercised their right to elect
         directors in any default period and during the continuance of such
         period, the number of directors shall not be increased or decreased
         except by vote of the holders of Preferred Stock as herein provided or
         pursuant to the rights of any equity securities ranking senior to or
         pari passu with the Series A Junior Participating Preferred Stock.

              (iii) Unless the holders of Preferred Stock shall, during an
         existing default period, have previously exercised their right to elect
         directors, the Board of Directors may order, or any stockholder or
         stockholders owning in the aggregate not less than ten percent (10%) of
         the total number of shares of Preferred Stock outstanding, irrespective
         of series, may request, the calling of a special meeting of the holders
         of Preferred Stock, which meeting shall thereupon be called by the
         President, a Vice-President or the Secretary of the Corporation. Notice
         of such meeting and of any annual meeting at which holders of Preferred
         Stock are entitled to vote pursuant to this Paragraph (C)(iii) shall be
         given to each holder of record of Preferred Stock by mailing a copy of
         such notice to him at his last address as the same appears on the books
         of the Corporation. Such meeting shall be called for a time not earlier
         than 20 days and not later than 60 days after such order or request or
         in default of the calling of such meeting within 60 days after such
         order or request, such meeting may be called on similar notice by any
         stockholder or stockholders owning in the aggregate not less than ten
         percent (10%) of the total number of shares of Preferred Stock
         outstanding. Notwithstanding the provisions of this Paragraph (C)(iii),
         no such special meeting shall be called during the period within 60
         days immediately preceding the date fixed for the next annual meeting
         of the stockholders.

              (iv)  In any default period, the holders of Common Stock, and
         other classes of stock of the Corporation if applicable, shall continue
         to be entitled to elect the whole number of directors until the holders
         of Preferred Stock shall have exercised their right to elect two (2)
         directors voting as a class, after the exercise of which right (x) the
         directors so elected by the holders of Preferred Stock shall continue
         in office until their successors shall have been elected by such
         holders or until the expiration of the default period, and (y) any
         vacancy in the Board of Directors may (except as provided in Paragraph
         (C)(ii) of this Section 3) be filled by vote of a majority of the
         remaining directors theretofore elected by the 
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         holders of the class of stock which elected the director whose office
         shall have become vacant. References in this Paragraph (C) to directors
         elected by the holders of a particular class of stock shall include
         directors elected by such directors to fill vacancies as provided in
         clause (y) of the foregoing sentence.

              (v)   Immediately upon the expiration of a default period, (x) the
         right of the holders of Preferred Stock as a class to elect directors
         shall cease, (y) the term of any directors elected by the holders of
         Preferred Stock as a class shall terminate, and (z) the number of
         directors shall be such number as may be provided for in the
         certificate of incorporation or by-laws irrespective of any increase
         made pursuant to the provisions of Paragraph (C)(ii) of this Section 3
         (such number being subject, however, to change thereafter in any manner
         provided by law or in the certificate of incorporation or by-laws). Any
         vacancies in the Board of Directors effected by the provisions of
         clauses (y) and (z) in the preceding sentence may be filled by a
         majority of the remaining directors.

         (D) Except as set forth herein, holders of Series A Junior
Participating Preferred Stock shall have no special voting rights and their
consent shall not be required (except to the extent they are entitled to vote
with holders of Common Stock as set forth herein) for taking any corporate
action.

         Section 4. Certain Restrictions.

         (A) Whenever quarterly dividends or other dividends or distributions
payable on the Series A Junior Participating Preferred Stock as provided in
Section 2 are in arrears, thereafter and until all accrued and unpaid dividends
and distributions, whether or not declared, on shares of Series A Junior
Participating Preferred Stock outstanding shall have been paid in full, the
Corporation shall not

              (i)   declare or pay dividends on, make any other distributions
         on, or redeem or purchase or otherwise acquire for consideration any
         shares of stock ranking junior (either as to dividends or upon
         liquidation, dissolution or winding up) to the Series A Junior
         Participating Preferred Stock;

              (ii)  declare or pay dividends on or make any other distributions
         on any shares of stock ranking on a parity (either as to dividends or
         upon liquidation, dissolution or winding up) with the Series A Junior
         Participating Preferred Stock, except dividends paid ratably on the
         Series A Junior Participating Preferred Stock and all such parity stock
         on which dividends are payable or in arrears in proportion to the total
         amounts to which the holders of all such shares are then entitled;

              (iii) redeem or purchase or otherwise acquire for consideration
         shares of any stock ranking on a parity (either as to dividends or upon
         liquidation, dissolution or winding up) with the Series A Junior
         Participating Preferred Stock, provided that the Corporation may at any
         time redeem, purchase or otherwise acquire shares of any such parity
         stock in exchange for shares of any stock of the Corporation 
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         ranking junior (either as to dividends or upon dissolution, liquidation
         or winding up) to the Series A Junior Participating Preferred Stock; or

              (iv)  purchase or otherwise acquire for consideration any shares
         of Series A Junior Participating Preferred Stock, or any shares of
         stock ranking on a parity with the Series A Junior Participating
         Preferred Stock, except in accordance with a purchase offer made in
         writing or by publication (as determined by the Board of Directors) to
         all holders of such shares upon such terms as the Board of Directors,
         after consideration of the respective annual dividend rates and other
         relative rights and preferences of the respective series and classes,
         shall determine in good faith will result in fair and equitable
         treatment among the respective series or classes.

         (B) The Corporation shall not permit any subsidiary of the Corporation
to purchase or otherwise acquire for consideration any shares of stock of the
Corporation unless the Corporation could, under Paragraph (A) of this Section 4,
purchase or otherwise acquire such shares at such time and in such manner.

         Section 5. Reacquired Shares. Any shares of Series A Junior
Participating Preferred Stock purchased or otherwise acquired by the Corporation
in any manner whatsoever shall be retired and cancelled promptly after the
acquisition thereof. All such shares shall upon their cancellation become
authorized but unissued shares of Preferred Stock and may be reissued as part of
a new series of Preferred Stock to be created by resolution or resolutions of
the Board of Directors, subject to the conditions and restrictions on issuance
set forth herein.

         Section 6. Liquidation, Dissolution or Winding Up. (A) Upon any
liquidation (voluntary or otherwise), dissolution or winding up of the
Corporation, no distribution shall be made to the holders of shares of stock
ranking junior (either as to dividends or upon liquidation, dissolution or
winding up) to the Series A Junior Participating Preferred Stock unless, prior
thereto, the holders of shares of Series A Junior Participating Preferred Stock
shall have received an amount equal to $100 per share of Series A Junior
Participating Preferred Stock, plus an amount equal to accrued and unpaid
dividends and distributions thereon, whether or not declared, to the date of
such payment (the "Series A Liquidation Preference"). Following the payment of
the full amount of the Series A Liquidation Preference, no additional
distributions shall be made to the holders of shares of Series A Junior
Participating Preferred Stock unless, prior thereto, the holders of shares of
Common Stock shall have received an amount per share (the "Common Adjustment")
equal to the quotient obtained by dividing (i) the Series A Liquidation
Preference by (ii) 100 (as appropriately adjusted as set forth in subparagraph
(C) below to reflect such events as stock splits, stock dividends and
recapitalizations with respect to the Common Stock) (such number in clause (ii),
the "Adjustment Number"). Following the payment of the full amount of the Series
A Liquidation Preference and the Common Adjustment in respect of all outstanding
shares of Series A Junior Participating Preferred Stock and Common Stock,
respectively, holders of Series A Junior Participating Preferred Stock and
holders of shares of Common Stock shall receive their ratable and proportionate
share of the remaining assets to be distributed in the ratio of the Adjustment
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Number to 1 with respect to such Preferred Stock and Common Stock, on a per
share basis, respectively.

         (B) In the event, however, that there are not sufficient assets
available to permit payment in full of the Series A Liquidation Preference and
the liquidation preferences of all other series of preferred stock, if any,
which rank on a parity with the Series A Junior Participating Preferred Stock,
then such remaining assets shall be distributed ratably to the holders of such
parity shares in proportion to their respective liquidation preferences. In the
event, however, that there are not sufficient assets available to permit payment
in full of the Common Adjustment, then such remaining assets shall be
distributed ratably to the holders of Common Stock.

         (C) In the event the Corporation shall at any time after the Rights
Declaration Date (i) declare any dividend on Common Stock payable in shares of
Common Stock, (ii) subdivide the outstanding Common Stock, or (iii) combine the
outstanding Common Stock into a smaller number of shares, then in each such case
the Adjustment Number in effect immediately prior to such event shall be
adjusted by multiplying such Adjustment Number by a fraction the numerator of
which is the number of shares of Common Stock outstanding immediately after such
event and the denominator of which is the number of shares of Common Stock that
were outstanding immediately prior to such event.

         Section 7. Consolidation, Merger, etc. In case the Corporation shall
enter into any consolidation, merger, combination or other transaction in which
the shares of Common Stock are exchanged for or changed into other stock or
securities, cash and/or any other property, then in any such case the shares of
Series A Junior Participating Preferred Stock shall at the same time be
similarly exchanged or changed in an amount per share (subject to the provision
for adjustment hereinafter set forth) equal to 100 times the aggregate amount of
stock, securities, cash and/or any other property (payable in kind), as the case
may be, into which or for which each share of Common Stock is changed or
exchanged. In the event the Corporation shall at any time after the Rights
Declaration Date (i) declare any dividend on Common Stock payable in shares of
Common Stock, (ii) subdivide the outstanding Common Stock, or (iii) combine the
outstanding Common Stock into a smaller number of shares, then in each such case
the amount set forth in the preceding sentence with respect to the exchange or
change of shares of Series A Junior Participating Preferred Stock shall be
adjusted by multiplying such amount by a fraction the numerator of which is the
number of shares of Common Stock outstanding immediately after such event and
the denominator of which is the number of shares of Common Stock that were
outstanding immediately prior to such event.

         Section 8. No Redemption. The shares of Series A Junior Participating
Preferred Stock shall not be redeemable.

         Section 9. Ranking. The Series A Junior Participating Preferred Stock
shall rank junior to all other series of the Corporation's Preferred Stock as to
the payment of dividends and the distribution of assets, unless the terms of any
such series shall provide otherwise.
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         Section 10. Amendment. At any time when any shares of Series A Junior
Participating Preferred Stock are outstanding, neither the Certificate of
Incorporation of the Corporation nor this Certificate of Designation shall be
amended in any manner which would materially alter or change the powers,
preferences or special rights of the Series A Junior Participating Preferred
Stock so as to affect them adversely without the affirmative vote of the holders
of a majority or more of the outstanding shares of Series A Junior Participating
Preferred Stock, voting separately as a class.

         Section 11. Fractional Shares. Series A Junior Participating Preferred
Stock may be issued in fractions of a share which shall entitle the holder, in
proportion to such holder's fractional shares, to exercise voting rights,
receive dividends, participate in distributions and to have the benefit of all
other rights of holders of Series A Junior Participating Preferred Stock.

         IN WITNESS WHEREOF, we have executed and subscribed this Certificate
and do affirm the foregoing as true under the penalties of perjury this 15th day
of December, 1998.

                                            /s/ Robert J. Towarnicki 
                                            ------------------------ 
                                            Chief Executive Officer


Attest:


 /s/ Richard H. Troy
-----------------------------
Richard H. Troy  
Secretary