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                                                                      EXHIBIT 99


              Important Information on Forward-Looking Statements

     Statements in the Company's Annual Report on Form 10-K, news releases and
other public documents, as well as oral statements that may be made by or on
behalf of the Company, and that are not statements of historical fact,
constitute "forward-looking statements" within the meaning of the Private
Securities Litigation Reform Act of 1995.  These forward-looking statements are
subject to known and unknown risks, uncertainties or other factors which may
cause the actual results of the Company to be materially different from the
historical results or from any results expressed or implied by the forward-
looking statements.  In addition to statements which explicitly describe such
risks and uncertainties, the terms "believes," "belief," "expects," "plans,"
"anticipates," "intends" and similar expressions identify forward-looking
statements.  All cautionary statements made in this Annual Report on Form 10-K
should be read as being applicable to all related forward-looking statements
wherever they appear.

     The following discussion identifies some important factors that may cause
the actual results, performance or achievements of the Company to be materially
different from any future results, performance or achievements expressed or
implied by such forward-looking statements.

(i)    Uncertainty of Future Profitability: The Company commenced the commercial
       sale of its first drug product, TOBI, in January 1998. Before then, the
       Company had no sources of operating revenues from any of its drug
       candidates and limited sources of revenue from grants and royalties. At
       December 31, 1997, the Company had an accumulated deficit of $100.8
       million. The Company's ability to achieve profitability will depend on
       its ability to successfully commercialize TOBI. There can be no assurance
       if or when the Company will achieve profitability.

(ii)   Dependence on TOBI. The Company's drug candidates other than TOBI are not
       expected to be commercially available for at least several years, if at
       all. The Company must depend on successfully marketing its only product,
       TOBI, in order to generate revenues to fund development of additional
       drug candidates. However, TOBI for cystic fibrosis may not achieve market
       acceptance. In addition, the Company may not be successful in developing
       other drug candidates as commercial products. The Company has seven years
       of marketing exclusivity for TOBI in the U.S. from the time of TOBI's
       approval in December 1997. However, tobramycin also has been approved by
       the FDA for intravenous and intrathecal (injection into spinal fluid)
       use. These generic formulations of tobramycin can be modified by
       pharmacists, physicians or patients for inhalation use. Although this
       practice is not approved by the FDA, it may continue and may have a
       material adverse effect on reimbursement levels, sales and market
       acceptance of TOBI. Furthermore, the Company could incur substantial
       costs in asserting any rights to prevent such uses under the Orphan Drug
       Act. See also Factor (vi): "Uncertain Ability to Protect Patents and
       Proprietary Technology."

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(iii)  Uncertainty of Third Party Reimbursement and Product Pricing: How
       successfully the Company can commercialize its products may depend, in
       part, on the extent to which reimbursement for the cost of such products
       will be available from third party payors, such as private health
       insurers or Medicaid in the U.S. Adequate reimbursement in the U.S. or
       foreign countries may not be available for any products the Company has
       developed or will develop. If adequate coverage and reimbursement levels
       are not provided by government and third-party payors for use of the
       Company's products, the market acceptance of those products would be
       adversely affected.

(iv)   Limited Sales and Marketing Capabilities: The company only recently
       established capabilities in sales, marketing and distribution of products
       in anticipation of TOBI's introduction in January 1998. These
       capabilities may not be sufficient or successful.

(v)    Limited Manufacturing Capability; Dependence on Suppliers: The Company
       relies on others to supply raw materials and manufacture TOBI according
       to the FDA's requirements. There can be no assurance that the Company
       will be able to obtain future supplies of bulk tobramycin on favorable
       terms, that contract manufacturers will be able to provide the Company
       with sufficient quantities of TOBI, or that the products supplied will
       meet the Company's and the FDA's specifications. The Company obtains bulk
       powdered PA-1648 from Kaneka Corporation, currently the only known
       manufacturer of the bulk powdered drug. The Company has no alternative
       supply source, although it believes that it has sufficient quantities of
       PA-1648 to complete Phase II testing.

(vi)   Uncertain Ability to Protect Patents and Proprietary Technology: The
       Company's ability to compete effectively depends on its ability to
       protect its proprietary technology in the U.S. and abroad. The Company
       intends to file applications as appropriate for patents covering
       formulation, composition of matter, or uses of its drug candidates, its
       proprietary processes and any significant gene sequences that it
       discovers. However, the Company may not obtain any patents for which it
       applies. Even if obtained, these patents may be challenged, invalidated
       or circumvented, or may not provide any competitive advantage. The
       Company also relies on trade secrets, know-how and continuing
       technological advancement to maintain its competitive position. The
       Company has entered into confidentiality and invention agreements with
       its employees and consultants, but there can be no assurance that each of
       these agreements will be honored. Moreover, the Company may not be able
       to effectively protect its patents or its rights to unpatented trade
       secrets, or others may independently develop substantially equivalent
       proprietary information.

(vii)  Government Regulation: The Company's research, clinical trials, drug
       production and marketing are subject to regulation by numerous
       governmental agencies in the U.S. and other countries. The effect of
       government regulation, or a change in the regulations, may be to increase
       product development costs, delay marketing of the Company's proposed
       products, or furnish a competitive advantage to the Company's
       competitors. Regulatory authorities may not approve any product
       candidates developed by the Company on a timely basis or at all. In
       addition, noncompliance with regulatory requirements could result in
       fines, injunctions, seizures of products, total or partial suspension of
       product marketing,
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       withdrawal of marketing approvals, or criminal prosecution, among other
       outcomes. Compliance with regulations may be burdensome.

(viii) Uncertainty of Drug Development and Clinical Trials: Results of initial
       studies of drug candidates are not necessarily indicative of results that
       will be obtained from subsequent or more extensive preclinical and
       clinical testing or long-term efficacy studies. Adverse or inconclusive
       clinical trial results could significantly delay regulatory filings or
       result in a filing for a narrower indication. There can be no assurance
       that the Company's research and development, preclinical testing,
       clinical trials, or long-term safety and efficacy studies will be
       successfully completed. The Company may not obtain regulatory approvals
       or may obtain approvals that are not as broad as sought. Even if the
       Company succeeds in obtaining the desired regulatory approval for a drug
       candidate, it may not be able to produce the drug candidates in
       commercial quantities at reasonable costs. Furthermore, products may not
       achieve market acceptance.

(ix)   Technological Change: The pharmaceutical business is characterized by
       extensive research efforts and rapid technological progress. New
       developments in molecular biology, medicinal pharmacology, recombinant
       DNA technology and other fields of biology and pharmaceutical chemistry
       are expected to continue at a rapid pace in industry and academia.
       Research and discoveries by others may render some or all of the
       Company's programs or drug candidates noncompetitive or obsolete.

(x)    Competition: Many companies, including well-known pharmaceutical
       companies, chemical companies and specialized genetic engineering
       companies, are engaged in developing pharmaceuticals for human
       therapeutic applications. Many of these companies have substantially
       greater financial, research and development, manufacturing, marketing and
       human resources than the Company and represent significant competition.
       Such companies may succeed in developing products that are more effective
       or less costly than any that may be developed by the Company and may also
       prove to be more successful than the Company in manufacturing and
       marketing.

(xi)   Product Liability: The Company's business exposes it to potential product
       liability risks which are inherent in the testing, manufacturing and
       marketing of human therapeutic products. The Company maintains insurance
       against product liability and defense costs in the amount of $25 million
       per occurrence and $25 million in the aggregate. There can be no
       assurance that product liability claims will not occur, that the Company
       will be able to obtain or maintain product liability insurance on
       acceptable terms, or that such insurance will provide adequate coverage
       against any potential claims.

(xii)  Use of Hazardous Materials: The Company's research and development
       involve the controlled use of hazardous, infectious and radioactive
       materials. The Company is subject to stringent federal, state and local
       laws, rules, regulations and policies governing the use, generation,
       manufacture, storage, air emission, effluent discharge, handling and
       disposal of certain materials and wastes. The Company may incur
       significant costs to comply with environmental laws, rules, regulations
       and policies. The business, financial position or
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       results of operations of the Company may be materially and adversely
       affected by current or future environmental laws, rules, regulations and
       policies or by any releases or discharges of materials which could be
       hazardous. The Company does not maintain a separate insurance policy to
       cover the risk of accidental injury or contamination from these
       materials.

(xiii) Dependence on Qualified Personnel: In view of the intense competition for
       qualified personnel in the pharmaceutical field, the Company may not be
       able to continue to attract and retain the qualified personnel necessary
       for the development of its business. The unexpected loss of the services
       of existing personnel, as well as the failure to recruit additional key
       scientific, technical and managerial personnel in a timely manner, would
       be detrimental to the Company's research and development programs and to
       its business.

(xiv)  Dependence on Others: The Company's strategy for the research,
       development and commercialization of its drug candidates and proprietary
       technologies may require it to enter into various arrangements with
       corporate and academic collaborators, licensors, licensees and others.
       There can be no assurance that any revenues or profits will be derived
       from such arrangements, or that the Company will be able to enter into
       future collaborations.

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(xv)   Stock Price Volatility: The market price of the Common Stock has
       fluctuated significantly, and is likely to do so in the future, as is
       typical for publicly traded emerging growth companies and
       biopharmaceutical companies. Factors such as results of clinical trials,
       announcements of new products by the Company or its competitors,
       regulatory actions, developments or disputes concerning patent or
       proprietary rights, and period-to-period fluctuations in the Company's
       financial results could have a significant impact on the market price of
       the Common Stock.

(xvi)  Access to Capital: The Company may need to raise substantial additional
       capital to fund its future operations. The Company may seek such
       additional funding through public or private financings or collaborative,
       licensing and other arrangements with corporate partners. If additional
       funds are raised by issuing equity securities, dilution to existing
       stockholders will result and future investors may be granted rights
       superior to those of existing stockholders. There can be no assurance,
       however, that additional financing will be available on acceptable or
       affordable terms when needed.