REVISED PRELIMINARY OPPOSITION PROXY MATERIAL

                      ASSET VALUE FUND LIMITED PARTNERSHIP
                          376 MAIN STREET, P.O. BOX 74
                              BEDMINSTER, NJ 07921
                                 (908) 234-1881



                                                                    July__, 1998

Dear Fellow Cortech Stockholder:

   
     We and two other  investors  ("Asset Value") own  approximately  15% of the
outstanding shares ("Cortech Shares") of Cortech, Inc. ("Cortech"),  which makes
us by far Cortech's  largest  stockholders.  We believe that the incumbent Board
has exercised poor judgment in governing Cortech and that Asset Value's nominees
would provide better  leadership  because they are not tied to what we think are
the  failures of the past.  That is why we are  seeking  control of the Board by
electing our nominees to the Board.1

     At the end of fiscal  1997,  Cortech  had net assets of only $15.4  million
after  losing  over $70  million  since  1993 in a  failed  attempt  to  exploit
Cortech's  technology.  The Board then proceeded to expend $673,000 of Cortech's
limited  resources  promoting a merger with  BioStar,  Inc.  (the  "Merger"),  a
company  with a $5.6  million  negative net worth even though Asset Value warned
the  Board  from  the  start  that  the  Merger  was  not  in the  interests  of
stockholders2 who, Asset Value said, would never approve such a transaction. The
Merger was  canceled  on May 7, 1998.  ONLY ASSET VALUE WAS WILLING TO SPEND ITS
TIME AND MONEY TO PUBLICLY OPPOSE THE MERGER!

       We ask you. Do you want Cortech led into the future by an incumbent
              Director or any other nominee connected to this past?

- --------
     1    Asset Value is also asking stockholders to approve an amendment to the
By-laws which would increase the number of directors from five to seven creating
a total of four vacancies. If these four vacancies are filled with Asset Value's
nominees,  control of Cortech  will  transfer  to Asset  Value.  Management  has
indicated that it may propose to declassify the Board which, if approved,  would
mean all five seats on the Board would be open. In this case,  Asset Value would
seek to elect five nominees who, if elected, would comprise the entire Board. If
the Board is not  declassified or increased,  Asset Value will seek to elect two
of its nominees to fill the two vacancies which would then be available.
    
     2    Asset Value has not retained an independent  financial adviser and its
conclusions  are  solely  based  on the  opinion  of its  manager,  Asset  Value
Management,  Inc. which was reached after reviewing  management's proxy material
for the Merger, including the opinion of management's financial adviser.






                              Don't take a chance.
                               Vote for a change.
                        Vote for Asset Value's nominees!

                                 MORE RED INK !
   
     After the  termination  of the  Merger,  Cortech's  Form 10-Q for the first
quarter of 1998 revealed that Cortech's  losses not only continued but increased
compared to last year. In a quarter with No research and development  activities
and No revenues,  Cortech still had  approximately  15 full-time3  employees and
general  and  administrative  expenses of  $1,522,000,  of which,  according  to
Cortech,  merger expense only accounted for  approximately  $673,000.  After the
Form10-Q was filed Kenneth Lynn, the former CEO, left Cortech,  taking with him,
what we would call,  a  "departure  bonus" of almost  $500,000,  another 3.5% of
Cortech's  remaining  cash of $14.3  million.  The  calculation  of the $500,000
departure  bonus was  derived by adding 20 months of salary  ($442,000),  future
consulting fees of an undisclosed  amount and health  insurance  coverage for 18
months  estimated at $600 per month as reported in  Cortech's  Form 8-K filed on
May 18, 1998.

                         What would this Board do next?

     Well one  thing it would not do -at  least  not  voluntarily-  is call this
Annual  Meeting  within the 13 months  required by Delaware  law.  Instead Asset
Value had to file a lawsuit to compel the Board to let  stockholders  decide who
will determine  Cortech's future. THIS MEETING WAS ORDERED BY THE CHANCERY COURT
OF DELAWARE ONLY AFTER A LAWSUIT WAS FILED BY ASSET VALUE TO COMPEL A MEETING.

     Ask yourself why the Cortech Board would spend Cortech's  limited resources
to defend against a demand to hold an annual meeting as required by law?




- ----------
     3    Cortech  does not  disclose  whether  there are  additional  part-time
employees and consultants  still hanging on. Asset Value considers a shutdown of
Cortech an  alternative  which must be considered,  particularly  in view of the
continued  losses  reported in the first quarter of 1998. Such a course however,
has risks,  including the possible further  diminishment of Cortech's technology
and the possible  cessation of Cortech as a going  concern.  The matter would be
further  evaluated  with  current  employees  once Asset Value  gained  control,
therefore, there is no assurance that Cortech would be shut down.







     We think one reason is because the Board and its  nominees did not want you
to ask this question:
    
                 ARE YOU BETTER OFF NOW THAN YOU WERE FIVE YEARS
                                      AGO?

     In what we think is the  biggest  bull  market in  history,  Cortech  Stock
prices  have  declined  from $18.25 per share in 1993 to $.50 per share in 1998,
making Cortech, by any comparison,  in our view, one of the poorest stock market
performers during this period. --AND THAT'S NO BULL!

   
                                  COMPARISON OF
                CORTECH'S STOCK PERFORMANCE (NASDAQ SYMBOL-CRTQ)
                                       TO
                      THE NASDAQ BIOTECHNOLOGY INDEX (IXBT)
                                     AND THE
                AMERICAN STOCK EXCHANGE BIOTECHNOLOGY INDEX (BTK)

 [GRAPH THE ABOVE]




               Cortech         IXBT        BTK
               ------          -----      ------
                                    
1993          $18.25          197.88      115.78

1994           14.25          161.40       82.06

1995            3.65625       304.30      133.77

1996            3.8125        314.48      144.56

1997            2.03125       304.89      163.28

7/17/1998        .50          335.15      144.16
    



                              NOT A PRETTY PICTURE!







   
                              TOO LITTLE, TOO LATE

     Seven months after Asset Value first asked for representation on the Board;
long after the Board was sued for misfeasance;  after Cortech had spent $673,000
on the failed Merger; after Cortech had lost another  approximately $3.4 million
from operations (from September 30, 1997 through March 31, 1998), finally on May
11, 1998 the Cortech  Board  expressed an interest in meeting with Asset Value's
manager,  Paul Koether. By this time, Asset Value had already spent or committed
significant  amounts of its own funds  (estimated to exceed  $125,000  including
counsel fees and management time) in opposing the Merger and in securing control
of the  Board  because  it  believed  that a change in course  for  Cortech  was
absolutely  essential  and because it believed  that a Board  controlled  by the
incumbents would not embrace the necessary changes. Asset Value thought that the
Board's offer to meet, in and of itself, was too little too late.

                  THE BOARD'S VERSION OF STOCKHOLDER DEMOCRACY

     This Board  called  this  Meeting  only after Asset Value filed to have the
Delaware courts compel the Board to hold the Meeting.  We ask you: Why would the
Board fail to call a meeting  within the time  required by law? Why is the Board
spending  your money and our money to delay  what we believe  will be the day of
reckoning when the  stockholders  will finally be given a choice between what in
our view,  is the  failed  past and what we think  will be a better  future.  In
making this choice, we ask you to consider that Asset Value has committed not to
seek to merge  Cortech  with any  affiliate or entity in which Asset Value is an
investor. Asset Value intends to benefit from its Cortech investment only to the
same extent other stockholders  benefit.  Moreover Asset Value's nominees do not
intend to take any fees for managing Cortech.

                               SAME OLD; SAME OLD

     Bert Fingerhut,  an incumbent  Cortech  director,  replaced Kenneth Lynn as
CEO. Mr.  Fingerhut  responded to Asset Value's request for majority  control of
the Board by offering to  declassify  the Board and to designate one Asset Value
nominee on a five member  slate.  In addition to himself and  incumbent  Charles
Cohen,  Mr.  Fingerhut's   proposed  slate  would  include  stockholders  Edward
Finkelstein and John Papp. Mr. Fingerhut  described Messrs  Finkelstein and Papp
as  newcomers  but we  believe  they  are  two  cronies  of  management.  As Mr.
Fingerhut,  himself disclosed,  "As you know, Mr. Finkelstein and his associates
have a significant ownership stake in Cortech" (although Mr. Finkelstein and his
unnamed  associates  presumably  own less than 5% since no Schedule 13D has been
filed) and "Dr. Papp is familiar with Cortech's  intellectual  property from his
service as a Director of CDC, a research and development  affiliate of Cortech."
(emphasis added).
    





                         TIME AND MONEY ARE RUNNING OUT!
   
     On May 18, 1998, CEO Kenneth Lynn left Cortech. We believe that Mr Lynn was
made a scapegoat for what we think is Cortech's prior mismanagement.  But in our
opinion, Mr. Lynn was a symptom of what is wrong with Cortech not the source, at
least, in our view, not the only source.  In the past five years  (including the
first quarter of 1998),  Cortech has lost over $70 million,  and as of March 31,
1998, had cash of only $14.3 million.  We ask, does Lynn's departure absolve the
incumbent Board members of their  responsibility  for these losses? We think the
answer is a resounding No!

                  PICTURE OF HOUR GLASS WITH CONTENTS READING



                                                             CASH REMAINING AT
                                                             MARCH 31, 1998
                                                             $14.3 million





                                                             CASH LOSSES FROM
                                                             INCEPTION (1982) TO
                                                             DATE $86 million!!!






     And we ask where were Mr. Fingerhut's recommended nominees, Mr. Finkelstein
and Dr. Papp while Cortech was losing all this money? Right behind the Board, we
think!
    






                         THE SHAPE OF THINGS TO COME 4

     So, what will Asset Value do if it obtains control of the Cortech Board? We
believe that once the Cortech Board determined to change control of Cortech,  it
should have sought competitive transactions more aggressively, by advertising in
the financial media, by engaging an investment banker from the outset to solicit
merger  partners and by publicly  stating that the Board was  conducting an open
bidding process for control of Cortech.  If elected Asset Value's  nominees will
take these  steps.  Asset Value has no specific  merger  partner in mind and has
considered possible alternatives for the future of Cortech only in a preliminary
way. In the course of its own business,  however, Asset Value constantly reviews
investment  opportunities and in connection with this process has seen companies
which might be attractive  strategic  partners for Cortech  although  additional
analysis would be required to determine whether any of these companies are a fit
with Cortech.

   
     The  principal  standards  for seeking a candidate  would be balance  sheet
quality and positive earnings.  Asset Value also believes that a private company
which seeks a public market or a public company which needs Cortech's  assets to
qualify  for  NASDAQ,  would  consider  these  attributes  as  well  as  cash in
calculating  Cortech's value. As of March 31, 1998,  Cortech's total assets were
$14.9 million of which cash and cash equivalents were $14.3 million. Asset Value
is not sure,  however,  that there are  potential  acquisitions  or mergers that
would be attractive for Cortech. One thing is certain however,  Asset Value will
not seek to merge  Cortech with any  affiliate or entity in which Asset Value is
an investor.  Asset Value intends to benefit from its Cortech investment only to
the same extent other stockholders benefit.
    
     Now it is time  for the  Annual  Meeting;  time  for  the  stockholders  to
re-evaluate  the past  leadership  of Cortech and time to consider a change.  We
believe that Asset Value has the same interests as all other  stockholders which
it believes will be a change from this management - a substantial change.

                              PLEASE ASK YOURSELF:
   
                 DO YOU WANT A BOARD COMPRISED OF ANY DIRECTORS
                  WHO SERVED WHILE CORTECH WAS LOSING ALL THIS
                                     MONEY?

               DO YOU WANT FUTURE TRANSACTIONS SELECTED BY ANYONE
              WHO EITHER APPROVED THE MERGER OR STOOD SILENT WHILE
                            THE MERGER MOVED FORWARD?

                  WE HOPE YOUR ANSWER WILL BE : CERTAINLY NOT!
    
               PLEASE SEND THE WHITE PROXY CARD TO ASSET VALUE AND


- --------
         4H.G. Wells




   
                VOTE TO DECLASSIFY THE BOARD(if it is proposed by
               management); TO INCREASE THE BOARD (if the Board is
                            not declassified) AND TO
                          ELECT ASSET VALUE'S NOMINEES.

                    IT'S TIME FOR A CHANGE; VOTE FOR CHANGE;
                              VOTE FOR ASSET VALUE.

                          SEND IN THE WHITE PROXY CARD
             VOTE YES TO DECLASSIFY THE BOARD (If it is proposed by
          management) OR TO INCREASE THE BOARD (if declassification is
                         not proposed) BUT IN ANY EVENT:

                     VOTE FOR ALL OF ASSET VALUE'S NOMINEES!
    
                                    IMPORTANT

     If your shares are held in "Street  Name" only your bank or broker can vote
your shares, and only upon receipt of your specific instructions. Please contact
the person  responsible  for your account and  instruct  them to execute a white
proxy card as soon as possible.

     If you have any questions or need further assistance in voting, please call
John W. Galuchie, Jr., of Asset Value Fund Limited Partnership collect at
(908) 234-1881, or our proxy solicitor:

                           BEACON HILL PARTNERS, INC.
                                 90 BROAD STREET
                            NEW YORK, NEW YORK 10004
                                 (800) 253-3814