Exhibit 99.1

FACTORS TO CONSIDER IN CONNECTION WITH FORWARD LOOKING STATEMENTS

             Development  Stage  Company,  Accumulated  Deficit,   Stockholders'
Deficiency and Uncertainty of Future Profitability. The Company is a development
stage company which is subject to all of the risks and  uncertainties  of such a
company,   including  uncertainties  of  product  development,   constraints  on
financial and personnel  resources and dependence  upon and need for third party
financing. The Company's profitability will depend primarily upon its success in
developing,  obtaining  regulatory  approvals  for,  and  effectively  marketing
ONCONASE.  ONCONASE  has not been  approved  by the United  States Food and Drug
Administration ("FDA").  Potential investors should be aware of the difficulties
a development  stage  enterprise  encounters,  especially in view of the intense
competition in the pharmaceutical industry in which the Company competes.  There
can be no assurance  that the Company's  plans will either  materialize or prove
successful,  that its products under development will be successfully  developed
or that such products will generate revenues sufficient to enable the Company to
earn a profit.  Since the Company's  incorporation in 1981, a significant source
of  cash  for  the  Company  has  been  public  and  private  placements  of its
securities. At July 31, 1996, and April 30, 1997, respectively,  the Company had
an  accumulated   deficit  of   approximately   $40,400,000,   and  $43,400,000,
respectively,  and a total stockholders' equity of approximately $6,700,000, and
$7,200,000, respectively. The Company anticipates that it will continue to incur
substantial losses in the future. The Company is pursuing  licensing,  marketing
and development  arrangements that may result in contract revenue to the Company
prior to its receiving revenues from commercial sales of ONCONASE.  To date, the
Company has not received any such revenues. There can be no assurance,  however,
that the Company will be able to successfully consummate any such arrangements.

             Need for, and Uncertainty of, Future Financing. The Company will be
required to expend significant funds on the further  development of ONCONASE and
its continued  operations will depend on its ability to raise  additional  funds
through equity or debt financings, collaborative agreements, strategic alliances
and revenues from the commercial sale of ONCONASE.  To date, the Company has had
several preliminary discussions regarding potential collaborative agreements and
strategic   alliances,   however  there  can  be  no  assurance  that  any  such
arrangements  will be consummated.  Indeed,  there can be no assurance that such
funds will be  available  to the Company on  acceptable  terms,  if at all.  The
Company believes that its cash on hand, including marketable  securities,  as of
April  30,  1997  will be  sufficient  to meet its  anticipated  cash  needs for
approximately  the next two years  assuming that a  significant  portion of such
cash  reserves is not used to repay the Term Loan.  The Company will be required
to raise  additional funds to meet its cash needs upon exhaustion of its current
cash resources.  The Company continues to be primarily financed by proceeds from
private placements of Common Stock and investments in its equity securities.  If
the Company is unable to secure  sufficient  future  financing or refinance  its
bank debt it may be  necessary  for the  Company to curtail or  discontinue  its
research and development activities.

             Government   Regulation;   No  Assurance  of  FDA   Approval.   The
pharmaceutical   industry  in  the  United   States  is  subject  to   stringent
governmental regulation and the sale of ONCONASE for use in humans in the United
States  will  require  the  prior  approval  of the FDA.  Similar  approvals  by
comparable  agencies  are  required  in  most  foreign  countries.  The  FDA has
established  mandatory  procedures  and  safety  standards  which  apply  to the
clinical  testing,   manufacture  and  marketing  of  pharmaceutical   products.
Pharmaceutical  manufacturing  facilities are also regulated by state, local and
other  authorities.  Obtaining FDA approval for a new therapeutic  drug may take
several  years  and  involve  substantial  expenditures.  ONCONASE  has not been
approved for sale in the United States or  elsewhere.  There can be no assurance
that the Company  will be able to obtain FDA approval for ONCONASE or any of its
future products.  Failure to obtain requisite  governmental approvals or failure
to obtain  approvals of the scope  requested  will delay or preclude the Company
from  marketing  its  products  while  under  patent  protection,  or limit  the
commercial use of the products,  and thereby may have a material  adverse effect
on  the  Company's  liquidity  and  financial   condition.   Further,   even  if
governmental approval is obtained, new drugs are subject to continual review and
a later discovery of previously  unknown  problems may result in restrictions on
the particular product, including withdrawal of such product from the market.

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             Uncertain  Ability to Protect Patents and  Proprietary  Technology.
The Company  believes it is important to develop new  technology and improve its
existing technology. When appropriate,  the Company files patent applications to
protect such inventions. The Company owns five U.S. Patents: (i) U.S. Patent No.
4,888,172  issued in 1989,  which covers a  pharmaceutical  for treating  tumors
derived from fertilized eggs of a frog species;  (ii) U.S. Patent No.  5,559,212
issued in 1996  which  covers  the  amino  acid  composition  and  structure  of
ONCONASE; and (iii) U.S. Patents Nos. 5,529,775 and 5,540,925 issued in 1996 and
U.S. Patent  No.5,595,734  issued in 1997, which cover  combinations of ONCONASE
with certain  other  chemotherapeutics.  The Company  also owns U.S.  Patent No.
4,882,421, which has now been disclaimed and is therefore legally unenforceable.
This  disclaimer  permitted the Company to obtain U.S.  Patents Nos.  5,529,775,
5,540,925 and 5,559,212.  The Company owns two European patents.  These European
patents cover ONCONASE, process technology for making ONCONASE, and combinations
of ONCONASE  with certain other  chemotherapeutics.  The Company also owns other
patent applications,  which are pending in the United States, Europe, and Japan.
Additionally,  the Company owns an undivided  interest in an application that is
pending in the United States.  This application  relates to a Subject  Invention
(as that term is defined in cooperative  research and development  agreements to
which the Company and the National  Institutes of Health are  parties).  Patents
covering biotechnological inventions have an uncertain scope, and the Company is
subject to this uncertainty.  The Company's patent applications may not issue as
patents.  Moreover,  the  Company's  patents may not  provide  the Company  with
competitive  advantages  and may not withstand  challenges by others.  Likewise,
patents  owned by others may  adversely  affect the ability of the Company to do
business.  Furthermore,  others may independently develop similar products,  may
duplicate the  Company's  products,  and may design around  patents owned by the
Company.  The Company's patent  protection is limited to that afforded under the
claims of its  issued  patents,  unless and until  other  patent  protection  is
available to the Company.  Although  the Company  believes  that its patents and
patent  applications  are of substantial  value to the Company,  there can be no
assurance  that such patents will be of  substantial  commercial  benefit to the
Company,  will afford the Company adequate protection from competing products or
will not be challenged or declared invalid.  The Company expects that there will
continue to be  significant  litigation  in the industry  regarding  patents and
other  proprietary  rights and, if the Company  were to become  involved in such
litigation,  there  could  be no  assurance  that  the  Company  would  have the
resources  necessary to litigate the contested issues  effectively.  Pursuant to
its loan agreement with the Company,  the Company's bank has a security interest
in the Company's patent portfolio.  The bank has agreed, however, to subordinate
its interest to licensees of the Company if certain conditions are met. The loss
of the rights to the Company's  patents  through the  enforcement  of the bank's
security interest could have a material adverse effect on the Company.

             Intense  Competition  and  Technological  Obsolescence.  There  are
several companies, universities, research teams and scientists, both private and
government-sponsored,   which  engage  in  developing   products  for  the  same
indications  as the Company.  Many of these entities and  associations  have far
greater financial resources,  larger research staffs and more extensive physical
facilities than the Company.  Several  competitors are more experienced and have
substantially  greater  clinical,  marketing  and  regulatory  capabilities  and
managerial  resources than the Company.  Such  competitors  may succeed in their
research and  development  of products for the same  indications  as the Company
prior to the Company achieving any measure of success in its efforts.

             The number of persons  skilled in the research and  development  of
pharmaceutical  products is limited and significant  competition exists for such
individuals.  As  a  result  of  this  competition  and  the  Company's  limited
resources,  the Company may find it difficult to attract skilled  individuals to
research, develop and investigate anti- cancer drugs in the future.

             The business in which the Company is engaged is highly  competitive
and involves rapid changes in the technologies of discovering, investigating and
developing new drugs.  Rapid  technological  development by others may result in
the  Company's   products  becoming  obsolete  before  the  Company  recovers  a
significant portion of the research,  development and commercialization expenses
incurred with respect to those products. Competitors of the Company are numerous
and are expected to increase as new technologies become available. The Company's
success depends upon  developing and  maintaining a competitive  position in the
development of new drugs and technologies

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in its area of focus.  There can be no assurance that, if attained,  the Company
will be able to maintain a competitive position in the pharmaceutical industry.

             Uncertain  Availability of Health Care  Reimbursement;  Health Care
Reform. The Company's ability to commercialize its product candidates may depend
in part on the extent to which  reimbursement for the costs of such product will
be available from government health administration  authorities,  private health
insurers  and others.  Significant  uncertainty  exists as to the  reimbursement
status of newly approved health care products.  There can be no assurance of the
availability  of adequate  third-party  insurance  reimbursement  coverage  that
enables the Company to  establish  and  maintain  price  levels  sufficient  for
realization  of an  appropriate  return  on its  investment  in  developing  its
products. Government and other third-party payors are increasingly attempting to
contain   health  care  costs  by  limiting  both  coverage  and  the  level  of
reimbursement for new therapeutic products approved for marketing by the FDA and
by  refusing,  in some  cases,  to provide  any  coverage  for uses of  approved
products  for disease  indications  for which the FDA has not granted  marketing
approval.  If adequate  coverage  and  reimbursement  levels are not provided by
government and third-party payors for uses of the Company's product  candidates,
the market acceptance of these products would be adversely affected.

             Health care reform  proposals have been  introduced in Congress and
in various state legislatures. It is currently uncertain whether any health care
reform  legislation  will be  enacted  at the  federal  level,  or what  actions
governmental  and private payors may take in response to the suggested  reforms.
The Company cannot  predict when any proposed  reforms will be  implemented,  if
ever, or the effect of any implemented reforms on the Company's business.  There
can be no  assurance  that any  implemented  reforms  will  not have a  material
adverse  effect on the  Company.  Such  reforms,  if  enacted,  may  affect  the
availability of third-party  reimbursement for products developed by the Company
as well as the price levels at which the Company is able to sell such  products.
In  addition,  if the  Company is able to  commercialize  products  in  overseas
markets, the Company's ability to achieve success in such markets may depend, in
part, on the health care financing and reimbursement policies of such countries.

             Potential  Product  Liability.  The use of the  Company's  products
during testing or after regulatory  approval entails an inherent risk of adverse
effects which could expose the Company to product liability claims.  The Company
maintains product liability insurance coverage in the total amount of $6,000,000
for claims arising from the use of its products in clinical  trials prior to FDA
approval.  There can be no  assurance  that the Company will be able to maintain
its existing  insurance  coverage or obtain coverage for the use of its products
in the future. Management believes that the Company maintains adequate insurance
coverage for the operation of its business at this time,  however,  there can be
no assurance that such insurance coverage and the resources of the Company would
be sufficient to satisfy any liability resulting from product liability claims.

             Dependence Upon Key Personnel.  The Company is currently managed by
a small number of key  management  and operating  personnel,  whose efforts will
largely determine the Company's success.  The loss of key management  personnel,
particularly Kuslima Shogen, the Company's Chairman and Chief Executive Officer,
would likely have a material  adverse  effect on the Company.  The bank may call
due all amounts  payable under the its term loan agreement with the Company (the
"Term Loan") in the event Ms. Shogen ceases for any reason,  except death, to be
a full time employee,  officer or director of the Company.  The Company  carries
key  person  life  insurance  on the  life of Ms.  Shogen  with a face  value of
$1,000,000. The Company's bank has been assigned this policy as security for the
approximately $1,400,000 outstanding under the Term Loan.

             No Dividends.  The Company has not paid any dividends on its Common
Stock since its  inception  and does not  currently  foresee the payment of cash
dividends  in the  future.  Furthermore,  under  the Term  Loan the  Company  is
prohibited  from paying any dividends  without the bank's  consent.  The Company
currently intends to retain all earnings, if any, to finance its operations.

     Preferred Stock;  Anti-takeover Device. The Company is currently authorized
to issue 1,000,000  shares of preferred  stock,  par value $.001 per share.  The
Company's Board of Directors is authorized, without any

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approval of the  stockholders,  to issue the  preferred  stock and determine the
terms of such  preferred  stock.  As of June 2,  1997,  there  were no shares of
preferred  stock  outstanding.  The authorized and unissued  shares of preferred
stock  may be  classified  as an  "anti-takeover"  measure  and  may  discourage
attempted  takeovers  of the  Company  which  are not  approved  by the Board of
Directors.  The authorized  shares of preferred stock will remain  available for
general  corporate  purposes,  may be privately placed and can be used to make a
change in control of the Company more  difficult.  Under certain  circumstances,
the Board of  Directors  could  create  impediments  to, or  frustrate,  persons
seeking to effect a takeover  or  transfer  in control of the Company by causing
such shares to be issued to a holder or holders who might side with the Board of
Directors in opposing a takeover bid that the Board of Directors  determines  is
not in the best  interests  of the  Company and its  stockholders,  but in which
unaffiliated stockholders may wish to participate. Under Delaware law, the Board
of Directors is permitted to use a depositary  receipt  mechanism  which enables
the Board to issue an unlimited  number of  fractional  interests in each of the
authorized and unissued shares of preferred stock without stockholder  approval.
Consequently,  the Board of Directors,  without  further  stockholder  approval,
could issue authorized shares of preferred stock or fractional interests therein
with  rights  that  could  adversely  affect  the  rights of the  holders of the
Company's  Common Stock to a holder or holders  which,  when voted together with
other  securities  held by members of the Board of Directors  and the  executive
officers  and their  families,  could  prevent  the  majority  stockholder  vote
required by the Company's certificate of incorporation or Delaware law to effect
certain  matters.  Furthermore,  the  existence  of such  authorized  shares  of
preferred stock might have the effect of  discouraging  any attempt by a person,
through the  acquisition of a substantial  number of shares of Common Stock,  to
acquire  control of the Company.  Accordingly,  the  accomplishment  of a tender
offer may be more  difficult.  This may be beneficial to management in a hostile
tender  offer,  but  have an  adverse  impact  on  stockholders  who may want to
participate in such tender offer.

     Control By Present Management.  The Company's officers and directors,  as a
group,  beneficially  owned 25.1% of the outstanding Common Stock of the Company
as of June 2, 1997 and thus could in some instances  exercise  effective control
over  the  Company.   The  Company's   Chief   Executive   Officer  has  pledged
substantially all of the shares of the Company's Common Stock beneficially owned
by her to secure repayment of the Term Loan.

             Volatility  and Possible  Reduction in Price of Common  Stock.  The
market  price of the Common  Stock,  like that of the  securities  of many other
development  stage  biotechnology  companies,  has been and may  continue to be,
highly volatile.  Factors such as announcements of technological  innovations or
new commercial products by the Company or its competitors, disclosure of results
of clinical  testing or  regulatory  proceedings,  governmental  regulation  and
approvals, developments in patent or other proprietary rights, public concern as
to the safety of products developed by the Company and general market conditions
may have a  significant  effect on the  market  price of the  Common  Stock.  In
addition,  the stock market has experienced and continues to experience  extreme
price and volume  fluctuations  which  have  effected  the market  price of many
biotechnology  companies.  These broad market  fluctuations,  as well as general
economic and political conditions,  may adversely effect the market price of the
Company's Common Stock.

             Dependence on Third Parties for Manufacturing. The Company does not
currently have  facilities  capable of  manufacturing  its product in commercial
quantities and, for the foreseeable future, the Company intends to rely on third
parties  to  manufacture  its  product.  If the  Company  were  to  establish  a
manufacturing  facility,  which it currently  does not intend to do, the Company
would  require  substantial  additional  funds and would be required to hire and
retain  significant  additional  personnel to comply with the extensive  current
Good Manufacturing  Practices ("cGMP") regulations of the FDA applicable to such
a facility. No assurance can be given that the Company would be able to make the
transition successfully to commercial production, if it chose to do so.

             Dependence on Third Parties for Marketing; No Marketing Experience.
Neither the Company nor any of its  officers  or  employees  has  pharmaceutical
marketing  experience.  The  Company  intends  to  enter  into  development  and
marketing  agreements  with third parties.  The Company  expects that under such
arrangements  it would act as a  co-marketing  partner or would grant  exclusive
marketing rights to its corporate partners in return

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for  up-front  fees,  milestone  payments and  royalties  on sales.  Under these
agreements,  the Company's  marketing partner may have the  responsibility for a
significant  portion of development of the product and regulatory  approval.  In
the event that the marketing  partner  fails to develop a marketable  product or
fails to market a product successfully,  the Company's business may be adversely
affected.  If the  Company  were to  market  its  products  itself,  significant
additional expenditures and management resources would be required to develop an
internal  sales force and there can be no  assurance  that the Company  would be
successful  in  penetrating  the  markets  for any  products  developed  or that
internal marketing capabilities would be developed at all.