SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                    FORM 10-Q

       (Mark One)

       [X]    Quarterly report pursuant to Section 13 or 15(d) of the Securities
              Exchange Act of 1934

       For the Quarterly Period Ended  March 31, 1998

                                       OR

       [ ]    Transition report pursuant to Section 13 or 15(d) of the
              Securities Exchange Act of 1934

                         Commission File Number: 0-19756

                            PROTEIN DESIGN LABS, INC.
             (Exact name of registrant as specified in its charter)

                   Delaware                               94-3023969
        (State or other jurisdiction of                (I.R.S. Employer
        incorporation or organization)              Identification Number)


                               2375 Garcia Avenue
                             Mountain View, CA 94043
                    (Address of principal executive offices)
                         Telephone Number (650) 903-3700

       Indicate by check mark whether the registrant (1) has filed all reports
       required to be filed by Section 13 or 15(d) of the Securities Exchange
       Act of 1934 during the preceding 12 months (or for such shorter period
       that the registrant was required to file such reports) and, (2) has been
       subject to such filing requirements for the past 90 days:

                          Yes [X]              No [ ]


       As of March 31, 1998, there were 18,511,656 shares of the Registrant's
       Common Stock outstanding.










PROTEIN DESIGN LABS, INC.


INDEX


PART I. FINANCIAL INFORMATION


                                                          Page No.

ITEM 1.  FINANCIAL STATEMENTS                                3

Statements of Operations
Three months ended March 31, 1998 and 1997                   3

Balance Sheets
March 31, 1998 and December 31, 1997                         4

Statements of Cash Flows
Three months ended March 31, 1998 and 1997                   5

Notes to Unaudited Financial Statements                      6


ITEM 2.  MANAGEMENT'S DISCUSSION AND ANALYSIS OF        
FINANCIAL CONDITION AND RESULTS OF OPERATIONS               10



PART II. OTHER INFORMATION

ITEM 5.   OTHER INFORMATION - RISK FACTORS                  14


ITEM 6.  EXHIBITS AND REPORTS ON FORM 8-K                   28
Signatures              



















                          PART I. FINANCIAL INFORMATION

ITEM 1.  FINANCIAL STATEMENTS
                            PROTEIN DESIGN LABS, INC.
                            STATEMENTS OF OPERATIONS
                                   (unaudited)

(In thousands, except net loss per share data)


                                  Three Months Ended
                                       March 31,
                               ---------------------
                                    1998       1997
                               ---------- ----------
                                    
Revenues:
  Research and development
   revenue under agreements
   with third parties             $1,791     $2,291

  Interest and other income        2,444      1,594
                               ---------- ----------
    Total revenues                 4,235      3,885

Costs and expenses:
  Research and development         6,406      6,503
  General and administrative       1,842      1,471
                               ---------- ----------
    Total costs and expenses       8,248      7,974
                               ---------- ----------
Net loss                         ($4,013)   ($4,089)
                               ========== ==========

Net loss per share                ($0.22)    ($0.26)
                               ========== ==========
Shares used in computation 
  of net loss per share
  (basic and diluted)             18,457     16,000
                               ========== ==========

                             See accompanying notes














                            PROTEIN DESIGN LABS, INC.
                                 BALANCE SHEETS
(In thousands, except par value per share)


                                                     March 31, December 31,
                                                       1998        1997
                                                   ----------  ----------
                                                   (unaudited)
                                                         
                     ASSETS
  Current assets:
     Cash and cash equivalents                       $24,597      $9,266
     Short-term investments                           96,274      63,003
     Other current assets                                836         779
                                                   ----------  ----------
      Total current assets                           121,707      73,048
     Property and equipment, net                       9,816       9,996
     Long-term investments                            42,565      91,386
     Other assets                                        579         596
                                                   ----------  ----------
                                                    $174,667    $175,026
                                                   ==========  ==========

        LIABILITIES AND STOCKHOLDERS' EQUITY
  Current liabilities:
     Accounts payable                                   $499        $475
     Accrued compensation                                914         833
     Accrued clinical trials                           1,206       1,434
     Other accrued liabilities                         1,458       2,212
     Deferred revenue                                  3,567       1,604
                                                   ----------  ----------
      Total current liabilities                        7,644       6,558

  Commitments

  Stockholders' equity:
     Preferred stock, par value $0.01 per
      share, 10,000 shares authorized;
      no shares issued and outstanding                   --          --
     Common stock, par value $0.01 per share,
      40,000 shares authorized; 18,512
      and 18,348 issued and outstanding at
      March 31, 1998 and December 31, 1997,
      respectively                                       185         183
     Additional paid-in capital                      229,824     227,093
     Accumulated deficit                             (63,395)    (59,382)
     Unrealized gain on investments                      409         574
                                                   ----------  ----------
      Total stockholders' equity                     167,023     168,468
                                                   ----------  ----------
                                                    $174,667    $175,026
                                                   ==========  ==========

                             See accompanying notes


                                  PROTEIN DESIGN LABS, INC.
                                   STATEMENTS OF CASH FLOWS
                       INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS
                                         (unaudited)
(In thousands)


                                                        Three Months Ended
                                                             March 31,
                                                     ----------------------
                                                         1998        1997
                                                     ----------  ----------
                                                           
Cash flows from operating activities:
  Net loss                                             ($4,013)    ($4,089)
  Adjustments to reconcile net loss to net
    cash used in operating activities:
    Depreciation and amortization                          833         789
    Other                                                  376         (91)
  Changes in assets and liabilities:
    Other current assets                                   (56)       (947)
    Accounts payable                                        24          34
    Accrued liabilities                                   (900)        168
    Deferred revenue                                     1,963          --
                                                     ----------  ----------
Total adjustments                                        2,240         (47)
                                                     ----------  ----------
    Net cash used in operating activities               (1,773)     (4,136)

Cash flows from investing activities:
  Purchases of short- and long-term investments        (41,979)    (22,822)
  Maturities of short- and long-term investments        57,000      14,050
  Capital expenditures                                    (665)       (842)
  (Increase) decrease in other assets                       16         (40)
                                                     ----------  ----------
    Net cash provided by (used in) investing 
      activities                                        14,372      (9,654)

Cash flows from financing activities:
  Proceeds from issuance of capital stock                2,732      69,485
                                                     ----------  ----------
    Net cash provided by financing activities            2,732      69,485
                                                     ----------  ----------

Net increase in cash and cash equivalents               15,331      55,695
Cash and cash equivalents at beginning of period         9,266      14,141
                                                     ----------  ----------
Cash and cash equivalents at end of period             $24,597     $69,836
                                                     ==========  ==========

                             See accompanying notes




                            PROTEIN DESIGN LABS, INC.
                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 1998

Summary of Significant Accounting Policies

Organization and Business

Since the Company's founding in 1986, a primary focus of its 
operations has been research and development. Achievement of 
successful research and development and commercialization of products 
derived from such efforts is subject to high levels of risk and 
significant resource commitments. The Company has a history of 
operating losses and expects to incur substantial additional expenses 
over at least the next few years, as it continues to develop its 
proprietary products, devote significant resources to preclinical 
studies, clinical trials, and manufacturing and to defend its patents 
and other proprietary rights. The Company's revenues to date have 
consisted principally of research and development funding, licensing 
and signing fees and milestone payments from pharmaceutical companies 
under collaborative research and development, humanization and patent 
licensing agreements. These revenues may vary considerably from 
quarter to quarter and from year to year, and revenues in any period 
may not be predictive of revenues in any subsequent period, and 
variations may be significant depending on the terms of the 
particular agreements. In 1998, the Company began receiving royalties 
from sales of Zenapax by Hoffmann-La Roche Inc., including its 
affiliates ("Roche"). The Company is dependent upon the further 
development, regulatory and marketing efforts of Roche with respect 
to Zenapax and there can be no assurance that Roche's further 
development, regulatory and marketing efforts will be successful, 
including, without limitation, if and when regulatory approvals in 
various countries may be obtained and whether or how quickly Zenapax 
might be adopted by the medical community. In addition, the Company 
intends to recognize royalty revenues when royalty reports are 
received from Roche and the Company's other collaborative partners. 
This method of recognizing royalty revenues from the Company's 
licensees, taken together with the unpredictable timing of payments 
of non-recurring licensing and signing fees and milestones under new 
and existing collaborative research and development, humanization and 
patent licensing agreements, may result in significant fluctuations 
in revenues in quarterly and yearly periods.

Although the Company anticipates entering into new collaborative, 
humanization and patent licensing agreements from time to time, the 
Company presently does not anticipate realizing non-royalty revenue 
from its new and proposed collaborations and agreements at levels 
commensurate with the non-royalty revenue historically recognized 
under its older collaborations. Moreover, the Company anticipates 
that its operating expenses will continue to increase significantly 
as the Company increases its research and development, manufacturing, 
preclinical and clinical activity, and administrative and patent 
activities. Accordingly, in the absence of substantial revenues from 
new corporate collaborations or patent licensing agreements, 
significant royalties on sales of Zenapax and other products licensed 
under the Company's intellectual property rights, or other sources, 
the Company expects to incur substantial operating losses in the 
foreseeable future as certain of its earlier stage potential products 
move into later stage clinical development, as additional potential 
products are selected as clinical candidates for further development, 
as the Company invests in additional facilities or manufacturing 
capacity, as the Company defends or prosecutes its patents and patent 
applications and as the Company invests in research or acquires 
additional technologies or businesses.

Basis of Presentation and Responsibility for Quarterly Financial 
Statements

The balance sheet as of March 31, 1998 and the statements of 
operations and cash flows for the three month periods ended March 31, 
1998 and 1997 are unaudited but include all adjustments (consisting 
of normal recurring adjustments) which the Company considers 
necessary for a fair presentation of the financial position at such 
dates and the operating results and cash flows for those periods. 
Although the Company believes that the disclosures in these financial 
statements are adequate to make the information presented not 
misleading, certain information and footnote information normally 
included in financial statements prepared in accordance with 
generally accepted accounting principles have been condensed or 
omitted pursuant to the rules and regulations of the Securities and 
Exchange Commission. The accompanying financial statements should be 
read in conjunction with the Company's Annual Report on Form 10-K, 
filed with the Securities and Exchange Commission for the year ended 
December 31, 1997. Results for any quarterly period are not 
necessarily indicative of results for any other quarterly period or 
for the entire year.

Cash Equivalents, Investments and Concentration of Credit Risk 

The Company considers all highly liquid investments purchased with a 
maturity of three months or less at the date of acquisition to be 
cash equivalents. The "Other" adjustments line item in the Statements 
of Cash Flows represents the accretion of the book value of certain 
debt securities. The Company places its cash and short-term and long-
term investments with high-credit-quality financial institutions and 
in securities of the U.S. government and U.S. government agencies 
and, by policy, limits the amount of credit exposure in any one 
financial instrument. To date, the Company has not experienced credit 
losses on investments in these instruments.

Revenue Recognition

Contract revenues from research and development are recorded as 
earned based on the performance requirements of the contracts. 
Revenues from achievement of milestone events are recognized when the 
funding party agrees that the scientific or clinical results 
stipulated in the agreement have been met. Deferred revenue arises 
principally due to timing of cash payments received under research 
and development contracts.

The Company's collaborative, humanization and patent licensing 
agreements with third parties provide for the payment of royalties to 
the Company based on net sales of the licensed product under the 
agreement. Royalties, as reported to the Company, may include 
deductions for creditable amounts related to milestone payments 
previously received by the Company. The agreements generally provide 
for royalty payments to the Company following completion of each 
calendar quarter or semi-annual period and royalty revenue is 
recognized when royalty reports are received from the third party.

New Accounting Standards 

Effective as of January 1, 1998, the Company adopted Financial 
Accounting Standards Board Statement No. 130, "Reporting 
Comprehensive Income" ("FAS 130"). FAS 130 establishes new rules for 
the reporting and display of comprehensive income (loss) and its 
components; however, the adoption of FAS 130 had no impact on the 
Company's net loss or stockholders' equity. FAS 130 requires 
unrealized gains and losses on the Company's available-for-sale 
securities, which prior to adoption were reported separately in 
stockholders' equity, to be included in other comprehensive income 
(loss). FAS 130 permits the disclosure of this information in notes 
to interim financial statements and the Company has elected this 
approach. During the first quarter of 1998 and 1997, total 
comprehensive loss amounted to $3.6 million and $4.2 million, 
respectively.

In 1997, the Financial Accounting Standards Board issued Statement 
No. 128, "Earnings Per Share" ("FAS 128"). Effective December 31, 
1997, the Company adopted FAS 128. FAS 128 requires the presentation 
of basic earnings (loss) per share and diluted earnings (loss) per 
share, if more dilutive, for all periods presented. In accordance 
with FAS 128, net loss per share has been computed using the weighted 
average number of shares of common stock outstanding during the 
period. Diluted net loss per share has not been presented as, due to 
the Company's net loss position, it is antidilutive. Had the Company 
been in a net income position, diluted earnings per share for the 
three month periods ended March 31, 1998 and 1997 would have included 
an additional 933,000 and 902,000 shares, respectively, related to 
the Company's outstanding stock options. The Company's previously 
reported net loss per share amounts conformed to FAS 128 and, 
accordingly, its adoption has no effect on these financial 
statements. 

Management Estimates 

The preparation of financial statements in conformity with generally 
accepted accounting principles requires the use of management's 
estimates and assumptions that affect the amounts reported in the 
financial statements and accompanying notes. For example, the Company 
has a policy of recording expenses for clinical trials based upon pro 
rating estimated total costs of a clinical trial over the estimated 
length of the clinical trial and the number of patients anticipated 
to be enrolled in the trial. Expenses related to each patient are 
recognized ratably beginning upon entry into the trial and over the 
course of the trial. In the event of early termination of a clinical 
trial, management accrues an amount based on its estimate of the 
remaining non-cancellable obligations associated with the winding 
down of the clinical trial. These estimates and assumptions could 
differ significantly from the amounts which may actually be realized.

In 1997, Boehringer Mannheim GmbH ("Boehringer Mannheim") invoked the 
dispute resolution provisions under its collaborative research 
agreement to address the reimbursement of up to $2.0 million for the 
Phase II study of OST 577 for the treatment of chronic hepatitis B 
("CHB") then being conducted by Boehringer Mannheim as well as 
certain legal expenses related to Boehringer Mannheim's participation 
in the Company's public offering in the first quarter of 1997. In 
March 1998, Roche acquired Corange Limited, the parent company of 
Boehringer Mannheim. The Company is unable to predict the outcome of 
this proceeding but in any event has estimated and recorded a 
liability with respect to this matter. The collaborative research 
agreement with Boehringer Mannheim provides for reimbursement from 
PDL of costs and expenses of up to $2.0 million for a Phase II study 
of OST 577 in the event certain conditions are met with respect to 
that study.






































ITEM 2.  MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL
          CONDITION AND RESULTS OF OPERATIONS

This Quarterly Report contains forward-looking statements which 
involve risks and uncertainties. The Company's actual results may differ 
significantly from the results discussed in the forward-looking 
statements. Factors that might cause such a difference include, but are 
not limited to those discussed in "Risk Factors" as well as those 
discussed elsewhere in this document and the Company's Annual Report on 
Form 10-K, filed with the Securities and Exchange Commission for the 
year ended December 31, 1997.

OVERVIEW 

Since the Company's founding in 1986, a primary focus of its 
operations has been research and development. Achievement of successful 
research and development and commercialization of products derived from 
such efforts is subject to high levels of risk and significant resource 
commitments. The Company has a history of operating losses and expects 
to incur substantial additional losses over at least the next few years, 
as it continues to develop its proprietary products, devote significant 
resources to preclinical studies, clinical trials, and manufacturing and 
to defend its patents and other proprietary rights. The Company's 
revenues to date have consisted principally of research and development 
funding, licensing and signing fees and milestone payments from 
pharmaceutical, chemical and biotechnology companies under collaborative 
research and development and patent licensing agreements. These revenues 
may vary considerably from quarter to quarter and year to year. Revenues 
in any period may not be predictive of revenues in any subsequent 
period, and variations may be significant depending on the terms of the 
particular agreements. In 1998, the Company began receiving royalties 
from sales of Zenapaxr by Hoffmann-La Roche Inc., including its 
affiliates ("Roche"). Roche has rights to partially offset certain 
previously paid milestones and third party royalties against royalties 
payable to the Company with respect to Zenapax. The Company is dependent 
upon the further development, regulatory and marketing efforts of Roche 
with respect to Zenapax and there can be no assurance that Roche's 
further development, regulatory and marketing efforts will be 
successful, including, without limitation, if and when regulatory 
approvals in various countries may be obtained and whether or how 
quickly Zenapax might be adopted by the medical community. Royalties 
from Zenapax are reported to the Company on a quarterly basis for U.S. 
sales and on a semi-annual basis for sales outside of the U.S. The 
Company intends to recognize royalty revenues when royalty reports are 
received from Roche and the Company's other collaborative partners. This 
method of recognizing royalty revenues from the Company's licensees, 
taken together with Roche's rights to partially offset third party 
royalties and certain milestone payments and the unpredictable timing of 
payments of non-recurring licensing and signing fees and milestones 
under new and existing collaborative research and development and patent 
licensing agreements, is likely to result in significant fluctuations in 
revenues in quarterly and yearly periods.

Although the Company anticipates entering into new collaborations 
and humanization and patent licensing agreements from time to time, the 
Company presently does not anticipate realizing non-royalty revenue from 
its new and proposed collaborations and agreements at levels 
commensurate with the non-royalty revenue recognized under its older 
collaborations. Moreover, the Company anticipates that its operating 
expenses will generally continue to increase significantly as the 
Company expands its business activities and advances potential products 
in clinical development, dedicates more resources to its research and 
development, manufacturing, preclinical and clinical activity, and 
administrative and patent activities. Accordingly, in the absence of 
substantial revenues from new corporate collaborations, humanization and 
patent licensing agreements, significant royalties on sales of Zenapax 
and other products licensed under the Company's intellectual property 
rights, or other sources, the Company expects to incur substantial 
operating losses in the foreseeable future as certain of its earlier 
stage potential products move into later stage clinical development, as 
additional potential products are selected as clinical candidates for 
further development, as the Company invests in additional facilities or 
manufacturing capacity, as the Company defends or prosecutes its patents 
and patent applications and as the Company invests in research or 
acquires additional technologies or businesses. 

Contract revenues from research and development are recorded as 
earned based on the performance requirements of the contracts. Revenues 
from achievement of milestone events are recognized when the funding 
party agrees that the scientific or clinical results stipulated in the 
agreement have been met. Deferred revenue arises principally due to 
timing of cash payments received under research and development 
contracts.

The Company's collaborative, humanization and patent licensing 
agreements with third parties provide for the payment of royalties to 
the Company based on net sales of the licensed product under the 
agreement. Royalties, as reported to the Company, may include deductions 
for creditable amounts related to milestone payments previously received 
by the Company. The agreements generally provide for royalty reports to 
the Company following completion of each calendar quarter or semi-annual 
period and royalty revenue is recognized when royalty reports are 
received from the third party.

RESULTS OF OPERATIONS 

Three Months Ended March 31, 1998 and 1997

The Company's total revenues for the three months ended March 31, 
1998 were $4.2 million as compared to $3.9 million in 1997. Total 
research and development revenues recognized from agreements with third 
parties were $1.8 million in the first quarter of 1998 compared to $2.3 
million in the comparable period in 1997. Interest and other income were 
$2.4 million in the first quarter of 1998 as compared to $1.6 million in 
the year-earlier period. This increase is primarily attributable to the 
increased interest earned on the Company's cash and cash equivalents 
balances as a result of the Company's follow-on public offering which 
was completed during the first quarter of 1997.

Research and development revenues from third parties of $1.8 
million for the three months ended March 31, 1998 consisted principally 
of research and development reimbursement funding, nominal royalties and 
milestone payments earned under licensing agreements. In the first 
quarter of 1997, research and development revenues from third parties 
consisted of $2.3 million of licensing and signing fees earned under 
licensing agreements.

Total costs and expenses for the three months ended March 31, 1998 
increased to $8.2 million from $8.0 million in the comparable period in 
1997. The increase in costs was primarily due to the addition of staff 
in the Company's pharmaceutical research and development programs, 
administrative functions and associated expenses necessary to manage and 
support the Company's expanding operations.

Research and development expenses for the three month period ended 
March 31, 1998 decreased to $6.4 million from $6.5 million in the 
comparable period in 1997. The Company's 1998 ongoing research and 
development expenses decreased as reduced expenses incurred in the 
operation of its manufacturing facility offset increased expenses due to 
the addition of staff, the continuation of clinical trials, costs of 
conducting preclinical tests and expansion of research and 
pharmaceutical development capabilities, including support for both 
clinical development and manufacturing process development. 

General and administrative expenses for the three months ended 
March 31, 1998 increased to $1.8 million from $1.5 million in the 
comparable period in 1997. These increases were primarily the result of 
increased staffing and associated expenses necessary to manage and 
support the Company's expanding operations.

LIQUIDITY AND CAPITAL RESOURCES 

To date the Company has financed its operations primarily through 
public and private placements of equity securities, research and 
development revenues and interest income on invested capital. At March 
31, 1998, the Company had cash, cash equivalents and investments in the 
aggregate of $163.4 million, compared to $163.7 million at December 31, 
1997. 

In 1997, Boehringer Mannheim GmbH ("Boehringer Mannheim") invoked 
the dispute resolution provisions under its collaborative research 
agreement with the Company to address the reimbursement of up to $2.0 
million for the Phase II study of OST 577 for the treatment of chronic 
hepatitis B ("CHB") then being conducted by Boehringer Mannheim as well 
as certain legal expenses related to Boehringer Mannheim's participation 
in the Company's public offering in the first quarter of 1997. In March 
1998, Roche acquired Corange Limited, the parent company of Boehringer 
Mannheim. The Company is unable to predict the outcome of this 
proceeding but in any event has estimated and recorded a liability with 
respect to this matter. The collaborative research agreement with 
Boehringer Mannheim provides for reimbursement from PDL of costs and 
expenses of up to $2.0 million for a Phase II study of OST 577 in the 
event certain conditions are met with respect to that study. 

As set forth in the Statements of Cash Flows, net cash used in 
operating activities was $1.8 million for the three months ended March 
31, 1998 compared to $4.1 million in the same period in 1997. The 
decrease in 1998 was primarily due to the Company receiving research and 
development reimbursement funding in advance of the related work to be 
performed by the Company.

As set forth in the Statements of Cash Flows, net cash provided by 
investing activities for the three months ended March 31, 1998 was $14.4 
million, resulting primarily from maturities of short-term investments. 
Net cash used in investing activities for the comparable period in 1997 
was $9.7 million reflecting the purchase of short- and long-term 
investments. 

As set forth in the Statements of Cash Flows, net cash provided by 
financing activities for the three months ended March 31, 1998 was $2.7 
million resulting primarily from the exercise of outstanding stock 
options. Net cash provided by financing activities for the comparable 
period in 1997 was $69.5 million. The 1997 amount resulted primarily 
from the completion of a public offering of 2.275 million shares of the 
Company's common stock in the first quarter of 1997.

The Company's future capital requirements will depend on numerous 
factors, including, among others, royalties from Roche's marketing of 
Zenapax; the ability of the Company to enter into additional 
collaborative, humanization and patent licensing arrangements; the 
progress of the Company's product candidates in clinical trials; the 
ability of the Company's collaborative partners to obtain regulatory 
approval and successfully manufacture and market the Company's products; 
the continued or additional support by collaborative partners or other 
third parties of research and clinical trials; enhancement of existing 
and investment in new research and development programs; the time 
required to gain regulatory approvals; the resources the Company devotes 
to self-funded products, manufacturing methods and advanced 
technologies; the ability of the Company to obtain and retain funding 
from third parties under collaborative agreements; the development of 
internal marketing and sales capabilities; the demand for the Company's 
potential products, if and when approved; potential acquisitions of 
technology, product candidates or businesses by the Company; and the 
costs of defending or prosecuting any patent opposition or litigation 
necessary to protect the Company's proprietary technology. In order to 
develop and commercialize its potential products the Company may need to 
raise substantial additional funds through equity or debt financings, 
collaborative arrangements, the use of sponsored research efforts or 
other means. No assurance can be given that such additional financing 
will be available on acceptable terms, if at all, and such financing may 
only be available on terms dilutive to existing stockholders. The 
Company believes that existing capital resources will be adequate to 
satisfy its capital needs through at least 2000. 











PART II.  OTHER INFORMATION


ITEM 5.  OTHER INFORMATION - RISK FACTORS

This Quarterly Report contains, in addition to historical 
information, forward-looking statements which involve risks and 
uncertainties. The Company's actual results may differ significantly 
from the results discussed in forward-looking statements. Factors that 
may cause such a difference include those discussed in the material set 
forth under "Risk Factors" and elsewhere in this document and in the 
Company's Annual Report on Form 10-K for the year ending December 31, 
1997.

     History Of Losses; Future Profitability Uncertain. The Company has 
a history of operating losses and expects to incur substantial 
additional expenses with resulting quarterly losses over at least the 
next several years as it continues to develop its potential products, to 
invest in new research areas and to devote significant resources to 
preclinical studies, clinical trials and manufacturing. As of March 31, 
1998, the Company had an accumulated deficit of approximately $63.4 
million. The time and resource commitment required to achieve market 
success for any individual product is extensive and uncertain. No 
assurance can be given that the Company, its collaborative partners or 
licensees will successfully develop products, obtain required regulatory 
approvals, manufacture products at an acceptable cost and with 
appropriate quality, or successfully market such products. 

The Company's revenues to date have consisted principally of 
research and development funding, licensing and signing fees and 
milestone payments from pharmaceutical, chemical and biotechnology 
companies under collaborative, humanization and patent licensing 
agreements. These revenues may vary considerably from quarter to quarter 
and from year to year, and revenues in any period may not be predictive 
of revenues in any subsequent period, and variations may be significant 
depending on the terms of the particular agreements.  In addition, 
revenues from patent licensing arrangements and royalties are expected 
to vary considerably from quarter to quarter and from year to year, and 
revenues in any period may not be predictive of revenues in any 
subsequent period, with significant variations depending on the terms of 
the particular agreements. For example, revenues in each of the quarters 
of 1997 included several non-recurring payments in connection with new 
humanization, patent licensing and other research and development 
agreements, which payments resulted in significant variations in 
revenues in each of the quarters in 1997.

Hoffmann-La Roche Inc., including its affiliates ("Roche") has 
received regulatory approval to distribute ZenapaxO in the U.S. and 
Switzerland. Zenapax, a product created by the Company, is licensed 
exclusively to Roche and the Company is dependent upon the efforts of 
Roche to obtain additional regulatory approvals and market Zenapax. The 
Company has begun receiving royalties in 1998 based on revenue from 
sales of Zenapax by Roche, with royalties based on U.S. sales paid to 
the Company on a quarterly basis and sales outside of the U.S. on a 
semi-annual basis. Roche has rights to partially offset third party 
royalties and certain previously paid milestones against royalties 
payable to the Company with respect to Zenapax. The Company intends to 
recognize royalty revenues when royalty reports are received from its 
collaborative partners, including Roche. This method of accounting for 
royalty revenues from the Company's licensees, taken together with the 
unpredictable timing of payments of non-recurring licensing and signing 
fees and milestones under new and existing collaborative, humanization 
and patent licensing agreements, is likely to result in significant 
quarterly fluctuations in revenues in quarterly and annual periods. 
Thus, revenues in any period may not be predictive of revenues in any 
subsequent period, and variations may be significant depending on the 
terms of the particular agreements. 

Although the Company anticipates entering into new collaborations 
from time to time, the Company presently does not anticipate continuing 
to realize non-royalty revenue from its new and proposed collaborations 
at levels commensurate with the revenue historically recognized under 
its older collaborations. Moreover, the Company anticipates that it will 
incur significant operating expenses as the Company increases its 
research and development, manufacturing, preclinical, clinical and 
administrative and patent activities. Accordingly, in the absence of 
substantial revenues from new corporate collaborations or patent 
licensing arrangements, royalties on sales of Zenapax or other products 
licensed under the Company's intellectual property rights or other 
sources, the Company expects to incur substantial operating losses in 
the foreseeable future as certain of its earlier stage potential 
products move into later stage clinical development, as additional 
potential products are selected as clinical candidates for further 
development, as the Company invests in new headquarters and additional 
laboratory and manufacturing facilities or capacity, as the Company 
defends or prosecutes its patents and patent applications, and as the 
Company invests in continuing and new research programs or acquires 
additional technologies, product candidates or businesses. For example, 
the Company expects to invest approximately $13 million related to the 
construction of its new headquarters facilities located in Fremont, 
California, which improvements will include the expansion of laboratory 
and development facilities. The amount of net losses and the time 
required to reach sustained profitability are highly uncertain. To 
achieve sustained profitable operations, the Company, alone or with its 
collaborative partners, must successfully discover, develop, 
manufacture, obtain regulatory approvals for and market potential 
products. No assurances can be given that the Company will be able to 
achieve or sustain profitability, and results are expected to fluctuate 
from quarter to quarter and year to year.

     Dependence On Roche With Respect To Zenapax. Roche controls the 
development and marketing of Zenapax, the most advanced of the Company's 
products in development, and the Company is dependent upon the resources 
and activities of Roche to pursue commercialization of Zenapax in order 
for the Company to receive royalties or additional milestone payments 
from the marketing and development of this product. There can be no 
assurance that Roche's further development, regulatory and marketing 
efforts will be successful, including without limitation, whether or how 
quickly Zenapax might receive regulatory approvals in addition to those 
in the U.S. and Switzerland and how rapidly it might be adopted by the 
medical community. In addition, there can be no assurance that other 
independently developed products of Roche, including CellCeptr, or 
others will not compete with or prevent Zenapax from achieving 
meaningful sales. Roche's development and marketing efforts for CellCept 
may result in delays or a relatively smaller resource commitment to 
product launch and support efforts than might otherwise be obtained for 
Zenapax if this potentially competitive product were not under 
development or being marketed. 

Moreover, Roche has stated that it plans to conduct or support 
other clinical trials of Zenapax in autoimmune indications. There can be 
no assurance that Roche will continue or pursue additional clinical 
trials in these indications or that, even if the additional clinical 
trials are completed, Zenapax will be shown to be safe and efficacious, 
or that the clinical trials will result in approval to market Zenapax in 
these indications. Any adverse event or announcement related to Zenapax 
would have a material adverse effect on the business and financial 
condition of the Company.

     Uncertainty Of Clinical Trial Results. Before obtaining regulatory 
approval for the commercial sale of any of its potential products, the 
Company must demonstrate through preclinical studies and clinical trials 
that the product is safe and efficacious for use in the clinical 
indication for which approval is sought. There can be no assurance that 
the Company will be permitted to undertake or continue clinical trials 
for any of its potential products or, if permitted, that such products 
will be demonstrated to be safe and efficacious. Moreover, the results 
from preclinical studies and early-stage clinical trials may not be 
predictive of results that will be obtained in late-stage clinical 
trials. Thus, there can be no assurance that the Company's present or 
future clinical trials will demonstrate the safety and efficacy of any 
potential products or will result in approval to market products.

In advanced clinical development, numerous factors may be involved 
that may lead to different results in larger, late-stage clinical trials 
from those obtained in early-stage trials. For example, early-stage 
clinical trials usually involve a small number of patients, often at a 
single center, and thus may not accurately predict the actual results 
regarding safety and efficacy that may be demonstrated with a large 
number of patients in a late-stage multi-center clinical trial. Also, 
differences in the clinical trial design between early-stage and late-
stage clinical trials may cause different results regarding the safety 
and efficacy of a product to be obtained. In addition, many early-stage 
trials are unblinded and based on qualitative evaluations by clinicians 
involved in the performance of the trial, whereas late-stage trials are 
generally required to be blinded in order to provide more objective data 
for assessing the safety and efficacy of the product. Moreover, 
preliminary results from early-stage trials may not be representative of 
results that may be obtained as the trial proceeds to completion. 

The Company may at times elect to aggressively enter potential 
products into Phase I/II trials to determine preliminary efficacy in 
specific indications. In addition, in certain cases the Company has 
commenced clinical trials without conducting preclinical animal testing 
where an appropriate animal model does not exist. Similarly, the Company 
or its partners at times will conduct potentially pivotal Phase II/III 
or Phase III trials based on limited Phase I or Phase I/II data. As a 
result of these and other factors, the Company anticipates that only 
some of its potential products will show safety and efficacy in clinical 
trials and that the number of products that fail to show safety and 
efficacy may be significant. 

     Limited Experience With Clinical Trials; Risk Of Delay. The 
Company has conducted only a limited number of clinical trials to date. 
There can be no assurance that the Company will be able to successfully 
commence and complete all of its planned clinical trials without 
significant additional resources and expertise. In addition, there can 
be no assurance that the Company will meet its contemplated development 
schedule for any of its potential products. The inability of the Company 
or its collaborative partners to commence or continue clinical trials as 
currently planned, to complete the clinical trials on a timely basis or 
to demonstrate the safety and efficacy of its potential products, would 
have a material adverse effect on the business and financial condition 
of the Company.

The rate of completion of the Company's or its collaborators' 
clinical trials is significantly dependent upon, among other factors, 
the rate of patient enrollment. Patient enrollment is a function of many 
factors, including, among others, the size of the patient population, 
perceived risks and benefits of the drug under study, availability of 
competing therapies, access to reimbursement from insurance companies or 
government sources, design of the protocol, proximity of and access by 
patients to clinical sites, patient referral practices, eligibility 
criteria for the study in question and efforts of the sponsor of and 
clinical sites involved in the trial to facilitate timely enrollment in 
the trial. Delays in the planned rate of patient enrollment may result 
in increased costs and expenses in completion of the trial or may 
require the Company to undertake additional studies in order to obtain 
regulatory approval if the applicable standard of care changes in the 
therapeutic indication under study. These considerations may lead the 
Company to consider the termination of ongoing clinical trials or 
halting further development of a product for a particular indication. 
For example, despite modifications to the clinical trial design in order 
to increase the rate of enrollment, patient accrual in the Company's 
ongoing Phase II/III trial of the SMART M195 Antibody in myeloid 
leukemia continues at a slower rate than the Company desires. There can 
be no assurance that any further actions by the Company to accelerate 
accrual in this trial will be successful or, to the extent that they 
involve modifications in the design of the trial, will not cause that 
trial to be considered a Phase II clinical trial and thereby require one 
or more additional potentially pivotal trials to be conducted. In 
addition, if patient accrual continues at the current rate, the Company 
expects to review the viability of the ongoing clinical trial in the 
second half of 1998 in order to determine whether to further modify or 
terminate this trial in order to dedicate resources to more promising 
clinical development programs, which programs may or may not include the 
SMART M195 Antibody.

     Uncertainty Of Patents And Proprietary Technology; Opposition 
Proceedings. The Company's success is significantly dependent on its 
ability to obtain patent protection for its products and technologies 
and to preserve its trade secrets and operate without infringing on the 
proprietary rights of third parties. The Company files and prosecutes 
patent applications to protect its inventions. No assurance can be given 
that the Company's pending patent applications will result in the 
issuance of patents or that any patents will provide competitive 
advantages or will not be invalidated or circumvented by its 
competitors. Moreover, no assurance can be given that patents are not 
issued to, or patent applications have not been filed by, other 
companies which would have an adverse effect on the Company's ability to 
use, manufacture or market its products or maintain its competitive 
position with respect to its products. Other companies obtaining patents 
claiming products or processes useful to the Company may bring 
infringement actions against the Company. As a result, the Company may 
be required to obtain licenses from others or not be able to use, 
manufacture or market its products. Such licenses may not be available 
on commercially reasonable terms, if at all.

Patents in the U.S. are issued to the party that is first to 
invent the claimed invention. Since patent applications in the U.S. are 
maintained in secrecy until patents issue, the Company cannot be certain 
that it was the first inventor of the inventions covered by its pending 
patent applications or that it was the first to file patent applications 
for such inventions. The patent positions of biotechnology firms 
generally are highly uncertain and involve complex legal and factual 
questions. No consistent policy has emerged regarding the breadth of 
claims in biotechnology patents, and patents of biotechnology products 
are uncertain so that even issued patents may later be modified or 
revoked by the U.S. Patent and Trademark Office ("PTO") or the courts in 
proceedings instituted by third parties. Moreover, the issuance of a 
patent in one country does not assure the issuance of a patent with 
similar claims in another country and claim interpretation and 
infringement laws vary among countries, so the extent of any patent 
protection may vary in different territories.

The Company has several patents and exclusive licenses covering 
its humanized and human antibody technology, respectively. With respect 
to its human antibody technology and antibodies, the Company has 
exclusively licensed certain patents from Novartis Pharmaceuticals 
Corporation ("Novartis") (formerly known as Sandoz Pharmaceuticals 
Corporation). With respect to its SMART antibody technology and 
antibodies, the Company has been issued fundamental patents by the 
European Patent Office ("EPO") and PTO. In addition, in June 1996 the 
Company was issued a U.S. patent covering Zenapax and certain related 
antibodies against the IL-2 receptor. The Company is also currently 
prosecuting other patent applications with the PTO and in other 
countries, including members of the European Patent Convention, Canada, 
Japan and Australia. The patent applications are directed to various 
aspects of the Company's SMART and human antibodies, antibody technology 
and other programs, and include claims relating to compositions of 
matter, methods of preparation and use of a number of the Company's 
compounds. However, the Company does not know whether any pending 
applications will result in the issuance of patents or whether such 
patents will provide protection of commercial significance. Further, 
there can be no assurance that the Company's patents will prevent others 
from developing competitive products using related technology.

With respect to its issued antibody humanization patents, the 
Company believes the patent claims cover Zenapax and, based on its 
review of the scientific literature, most humanized antibodies. The EPO 
(but not PTO) procedures provide for a nine-month opposition period in 
which other parties may submit arguments as to why the patent was 
incorrectly granted and should be withdrawn or limited. Eighteen notices 
of opposition to the Company's European patent were filed during the 
opposition period, including oppositions by major pharmaceutical and 
biotechnology companies, which cited references and made arguments not 
considered by the EPO and PTO before grant of the respective patents. 
The entire opposition process, including appeals, may take several years 
to complete, and during this lengthy process, the validity of the EPO 
patent will be at issue, which may limit the Company's ability to 
negotiate or collect royalties or to negotiate future collaborative 
research and development agreements based on this patent. The Company 
intends to vigorously defend the European and, if necessary, the U.S. 
patent; however, there can be no assurance that the Company will prevail 
in the opposition proceedings or any litigation contesting the validity 
or scope of these patents. If the outcome of the European opposition 
proceeding or any litigation involving the Company's antibody 
humanization patents were to be unfavorable, the Company's ability to 
collect royalties on licensed products and to license its patents 
relating to humanized antibodies may be materially adversely affected, 
which could have a material adverse affect on the business and financial 
conditions of the Company. In addition, such proceedings or litigation, 
or any other proceedings or litigation to protect the Company's 
intellectual property rights or defend against infringement claims by 
others, could result in substantial costs and a diversion of 
management's time and attention, which could have a material adverse 
effect on the business and financial condition of the Company.

A number of companies, universities and research institutions have 
filed patent applications or received patents in the areas of antibodies 
and other fields relating to the Company's programs. Some of these 
applications or patents may be competitive with the Company's 
applications or contain claims that conflict with those made under the 
Company's patent applications or patents. Such conflict could prevent 
issuance of patents to the Company, provoke an interference with the 
Company's patents or result in a significant reduction in the scope or 
invalidation of the Company's patents, if issued. An interference is an 
administrative proceeding conducted by the PTO to determine the priority 
of invention and other matters relating to the decision to grant 
patents. Moreover, if patents are held by or issued to other parties 
that contain claims relating to the Company's products or processes, and 
such claims are ultimately determined to be valid, no assurance can be 
given that the Company would be able to obtain licenses to these patents 
at a reasonable cost, if at all, or to develop or obtain alternative 
technology.

The Company is aware that Celltech Limited ("Celltech") has been 
granted a patent by the EPO covering certain humanized antibodies, which 
PDL has opposed, and that Celltech has a pending application for a 
corresponding U.S. patent (the "U.S. Adair Patent Application"). Because 
U.S. patent applications are maintained in secrecy, the U.S. Adair 
Patent Application remains confidential. Accordingly, there can be no 
assurance that claims in such a patent or application would not cover 
any of the Company's SMART antibodies or be competitive with or conflict 
with claims in the Company's patents or patent applications. If the U.S. 
Adair Patent Application issues and if it is determined to be valid and 
to cover any of the Company's SMART antibodies, there can be no 
assurance that PDL would be able to obtain a license on commercially 
reasonable terms, if at all. If the claims of the U.S. Adair Patent 
Application conflict with claims in the Company's patents or patent 
applications, there can be no assurance that an interference would not 
be declared by the PTO, which could take several years to resolve and 
could involve significant expense to the Company. Also, such conflict 
could prevent issuance of additional patents to PDL relating to 
humanization of antibodies or result in a significant reduction in the 
scope or invalidation of the Company's patents, if issued. Moreover, 
uncertainty as to the validity or scope of patents issued to the Company 
relating generally to humanization of antibodies may limit the Company's 
ability to negotiate or collect royalties or to negotiate future 
collaborative research and development agreements based on these 
patents.

The Company has obtained a nonexclusive license under a patent 
held by Celltech (the "Boss Patent") relating to the Company's current 
process for producing SMART and human antibodies. An interference 
proceeding was declared in early 1991 by the PTO between the Boss Patent 
and a patent application filed by Genentech, Inc. ("Genentech") to which 
the Company does not have a license. The Company is not a party to this 
proceeding, and the timing and outcome of the proceeding or the scope of 
any patent that may be subsequently issued cannot be predicted. If the 
Genentech patent application were held to have priority over the Boss 
Patent, and if it were determined that the Company's processes and 
products were covered by a patent issuing from such patent application, 
the Company may be required to obtain a license under such patent or to 
significantly alter its processes or products. There can be no assurance 
that the Company would be able to successfully alter its processes or 
products to avoid infringing such patent or to obtain such a license on 
commercially reasonable terms, if at all, and the failure to do so could 
have a material adverse effect on the Company.

The Company is aware that Lonza Biologics, Inc. has a patent 
issued in Europe to which the Company does not have a license (although 
Roche has advised the Company that it has a license covering Zenapax), 
which may cover the process the Company uses to produce its potential 
products. If it were determined that the Company's processes were 
covered by such patent, the Company might be required to obtain a 
license under such patent or to significantly alter its processes or 
products, if necessary to manufacture or import its products in Europe. 
There can be no assurance that the Company would be able to successfully 
alter its processes or products to avoid infringing such patent or to 
obtain such a license on commercially reasonable terms, if at all, and 
the failure to do so could have a material adverse effect on the 
business and financial condition of the Company.

Also, Genentech has patents in the U.S. and Europe that relate to 
chimeric antibodies. Although the European patent was declared invalid 
by the EPO in the opposition process, Genentech has appealed that 
decision, thereby staying that decision. If Genentech were to assert 
that the Company's SMART antibodies infringe these patents, the Company 
might have to choose whether to seek a license or to challenge in court 
the validity of such patents or Genentech's claim of infringement. There 
can be no assurance that the Company would be successful in either 
obtaining such a license on commercially reasonable terms, if at all, or 
that it would be successful in such a challenge of the Genentech 
patents, and the failure to do so could have a material adverse effect 
on the business and financial condition of the Company.

In addition to seeking the protection of patents and licenses, the 
Company also relies upon trade secrets, know-how and continuing 
technological innovation which it seeks to protect, in part, by 
confidentiality agreements with employees, consultants, suppliers and 
licensees. There can be no assurance that these agreements will not be 
breached, that the Company would have adequate remedies for any breach 
or that the Company's trade secrets will not otherwise become known, 
independently developed or patented by competitors.

     Dependence On Collaborative Partners. The Company has 
collaborative agreements with several pharmaceutical or other companies 
to develop, manufacture and market certain potential products, which 
include Zenapax, the most advanced product of the Company. The Company 
granted its collaborative partners certain exclusive rights to 
commercialize the products covered by these collaborative agreements. In 
some cases, the Company is relying on its collaborative partners to 
conduct clinical trials, to compile and analyze the data received from 
such trials, to obtain regulatory approvals and, if approved, to 
manufacture and market these licensed products. As a result, the Company 
often has little or no control over the development and marketing of 
these potential products and little or no opportunity to review clinical 
data prior to or following public announcement.

The Company's collaborative research agreements are generally 
terminable by its partners on short notice. Suspension or termination of 
certain of the Company's current collaborative research agreements could 
have a material adverse effect on the Company's operations and could 
significantly delay the development of the affected products. Continued 
funding and participation by collaborative partners will depend on the 
timely achievement of research and development objectives by the 
Company, the retention of key personnel performing work under those 
agreements and the successful achievement of clinical trial goals, none 
of which can be assured, as well as on each collaborative partner's own 
financial, competitive, marketing and strategic considerations. Such 
considerations include, among other things, the commitment of management 
of the collaborative partners to the continued development of the 
licensed products, the relationships among the individuals responsible 
for the implementation and maintenance of the collaborative efforts, the 
relative advantages of alternative products being marketed or developed 
by the collaborators or by others, including their relative patent and 
proprietary technology positions, and their ability to manufacture 
potential products successfully. In this regard, Boehringer Mannheim 
GmbH ("Boehringer Mannheim") recently terminated further development of 
and its license to OST 577, the most advanced product in development 
under the agreement with Boehringer Mannheim. In order to proceed with 
further clinical development of OST 577, the Company is dependent upon 
Boehringer Mannheim to transfer technical data, existing clinical 
supplies and other regulatory information related to OST 577 to the 
Company in a timely manner. There can be no assurance that Boehringer 
Mannheim will cooperate with the Company in providing any of such data, 
supplies or information in a manner that will permit the Company to 
easily or rapidly proceed with further clinical development of OST 577. 
In addition, Boehringer Mannheim has invoked the dispute resolution 
provisions under its collaborative research agreement to address the 
reimbursement of up to $2.0 million for the Phase II study of OST 577 
for the treatment of chronic hepatitis B ("CHB") conducted by Boehringer 
Mannheim. The Company is unable to predict the outcome of this 
proceeding but in any event has estimated and recorded a liability with 
respect to this matter.

Further, in March 1998 Roche acquired Corange Limited, the parent 
company of Boehringer Mannheim. The Company has not been advised of any 
anticipated changes to the existing collaborative arrangement with the 
Company resulting from the completed acquisition. However, the Company 
expects that Roche will review the various drug development programs of 
the Company and Boehringer Mannheim, including those for the 
SMARTOAnti-L-Selectin Antibody and an antibody to an undisclosed 
cardiovascular target. The Company cannot predict the outcome or timing 
of such review or whether or not it will occur and in particular, 
whether Roche will decide to continue, modify or terminate the 
development program for these antibodies. In addition, Roche acquired 
1,682,877 shares of the Company's common stock held by Corange which are 
no longer subject to contractual limitations on disposition.

The Company's ability to enter into new collaborations and the 
willingness of the Company's existing collaborators to continue 
development of the Company's potential products depends upon, among 
other things, the Company's patent position with respect to such 
products. In this regard, the Company has been issued patents by PTO and 
EPO with claims that the Company believes, based on its survey of the 
scientific literature, cover most humanized antibodies. Eighteen notices 
of opposition to the European patent have been filed with the EPO, and 
either or both patents may be further challenged through administrative 
or judicial proceedings. The Company has applied for similar patents in 
Japan and other countries. The Company has entered into several 
collaborations related to both the humanization and patent licensing of 
certain antibodies whereby it granted licenses to its patent rights 
relating to such antibodies, and the Company anticipates entering into 
additional collaborations and patent licensing agreements partially as a 
result of the Company's patent and patent applications with respect to 
humanized antibodies. As a result, the inability of the Company to 
successfully defend the opposition proceeding before the EPO or, if 
necessary, to defend patents granted by the PTO or EPO or to 
successfully prosecute the corresponding patent applications in Japan or 
other countries could adversely affect the ability of the Company to 
collect royalties on existing licensed products such as Zenapax, and 
enter into additional collaborations, humanization or patent licensing 
agreements and could therefore have a material adverse effect on the 
Company's business or financial condition. 

     Absence Of Manufacturing Experience. Of the products developed by 
the Company which are currently in clinical development, Roche is 
responsible for manufacturing Zenapax. If further development occurs, 
the Company intends to manufacture OST 577, the SMART M195 Antibody, the 
SMART Anti-CD3 Antibody and PROTOVIR as well as some or all of its other 
products in preclinical development. The Company currently leases 
approximately 47,000 square feet housing its manufacturing facilities in 
Plymouth, Minnesota. The Company intends to continue to manufacture 
potential products for use in preclinical and clinical trials using this 
manufacturing facility in accordance with standard procedures that 
comply with current Good Manufacturing Practices ("cGMP") and 
appropriate regulatory standards. The manufacture of sufficient 
quantities of antibody products in accordance with such standards is an 
expensive, time-consuming and complex process and is subject to a number 
of risks that could result in delays. For example, the Company has 
experienced some difficulties in the past in manufacturing certain 
potential products on a consistent basis. Production interruptions, if 
they occur, could significantly delay clinical development of potential 
products, reduce third party or clinical researcher interest and support 
of proposed clinical trials, and possibly delay commercialization of 
such products and impair their competitive position, which would have a 
material adverse effect on the business and financial condition of the 
Company. 

The Company has no experience in manufacturing commercial 
quantities of its potential products and currently does not have 
sufficient capacity to manufacture its potential products on a 
commercial scale. In order to obtain regulatory approvals and to create 
capacity to produce its products for commercial sale at an acceptable 
cost, the Company will need to improve and expand its existing 
manufacturing capabilities, including demonstration to the FDA of its 
ability to manufacture its products using controlled, reproducible 
processes. Accordingly, the Company is evaluating plans to improve and 
expand the capacity of its current manufacturing facility. Such plans, 
if fully implemented, would result in substantial costs to the Company 
and may require a suspension of manufacturing operations during 
construction. There can be no assurance that construction delays would 
not occur, and any such delays could impair the Company's ability to 
produce adequate supplies of its potential products for clinical use or 
commercial sale on a timely basis. Further, there can be no assurance 
that the Company will successfully improve and expand its manufacturing 
capability sufficiently to obtain necessary regulatory approvals and to 
produce adequate commercial supplies of its potential products on a 
timely basis. Failure to do so could delay commercialization of such 
products and impair their competitive position, which could have a 
material adverse effect on the business or financial condition of the 
Company.

     Uncertainties Resulting From Manufacturing Changes. Manufacturing 
of antibodies for use as therapeutics in compliance with regulatory 
requirements is complex, time-consuming and expensive. When certain 
changes are made in the manufacturing process, it is necessary to 
demonstrate to the FDA that the changes have not caused the resulting 
drug material to differ significantly from the drug material previously 
produced, if results of prior preclinical studies and clinical trials 
performed using the previously produced drug material are to be relied 
upon in regulatory filings. Such changes could include, for example, 
changing the cell line used to produce the antibody, changing the 
fermentation or purification process or moving the production process to 
a new manufacturing plant. Depending upon the type and degree of 
differences between the newer and older drug material, various studies 
could be required to demonstrate that the newly produced drug material 
is sufficiently similar to the previously produced drug material, 
possibly requiring additional animal studies or human clinical trials. 
Manufacturing changes have been made or are likely to be made for the 
production of the Company's products currently in clinical development, 
in particular OST 577. There can be no assurance that such changes will 
not result in delays in development or regulatory approvals or, if 
occurring after regulatory approval, in reduction or interruption of 
commercial sales. In addition, manufacturing changes to its 
manufacturing facility may require the Company to shut down production 
for a period of time. There can be no assurance that the Company will be 
able to reinitiate production in a timely manner, if at all, following 
such shutdown. Delays as a result of manufacturing changes or shutdown 
of the manufacturing facility could have an adverse effect on the 
competitive position of those products and could have a material adverse 
effect on the business and financial condition of the Company.

     Dependence On Suppliers. The Company is dependent on outside 
vendors for the supply of raw materials used to produce its product 
candidates. The Company currently qualifies only one or a few vendors 
for its source of certain raw materials. Therefore, once a supplier's 
materials have been selected for use in the Company's manufacturing 
process, the supplier in effect becomes a sole or limited source of such 
raw materials to the Company due to the extensive regulatory compliance 
procedures governing changes in manufacturing processes. Although the 
Company believes it could qualify alternative suppliers, there can be no 
assurance that the Company would not experience a disruption in 
manufacturing if it experienced a disruption in supply from any of these 
sources. Any significant interruption in the supply of any of the raw 
materials currently obtained from such sources, or the time and expense 
necessary to transition a replacement supplier's product into the 
Company's manufacturing process, could disrupt the Company's operations 
and have a material adverse effect on the business and financial 
condition of the Company. A problem or suspected problem with the 
quality of raw materials supplied could result in a suspension of 
clinical trials, notification of patients treated with products or 
product candidates produced using such materials, potential product 
liability claims, a recall of products or product candidates produced 
using such materials, and an interruption of supplies, any of which 
could have a material adverse effect on the business or financial 
condition of the Company.

     Competition; Rapid Technological Change. The Company's potential 
products are intended to address a wide variety of disease conditions, 
including autoimmune diseases, inflammatory conditions, cancers and 
viral infections. Competition with respect to these disease conditions 
is intense and is expected to increase. This competition involves, among 
other things, successful research and development efforts, obtaining 
appropriate regulatory approvals, establishing and defending 
intellectual property rights, successful product manufacturing, 
marketing, distribution, market and physician acceptance, patient 
compliance, price and potentially securing eligibility for reimbursement 
or payment for the use of the Company's product. The Company believes 
its most significant competitors may be fully integrated pharmaceutical 
companies with substantial expertise in research and development, 
manufacturing, testing, obtaining regulatory approvals, marketing and 
securing eligibility for reimbursement or payment, and substantially 
greater financial and other resources than the Company. Smaller 
companies also may prove to be significant competitors, particularly 
through collaborative arrangements with large pharmaceutical companies. 
Furthermore, academic institutions, governmental agencies and other 
public and private research organizations conduct research, seek patent 
protection, and establish collaborative arrangements for product 
development, clinical development and marketing. These companies and 
institutions also compete with the Company in recruiting and retaining 
highly qualified personnel. The biotechnology and pharmaceutical 
industries are subject to rapid and substantial technological change. 
The Company's competitors may develop and introduce other technologies 
or approaches to accomplishing the intended purposes of the Company's 
products which may render the Company's technologies and products 
noncompetitive and obsolete.

In addition to currently marketed competitive drugs, the Company 
is aware of potential products in research or development by its 
competitors that address all of the diseases being targeted by the 
Company. These and other products may compete directly with the 
potential products being developed by the Company. In this regard, the 
Company is aware that potential competitors are developing antibodies or 
other compounds for treating autoimmune diseases, inflammatory 
conditions, cancers and viral infections. In particular, a number of 
other companies have developed and will continue to develop human and 
humanized antibodies. In addition, protein design is being actively 
pursued at a number of academic and commercial organizations, and 
several companies have developed or may develop technologies that can 
compete with the Company's SMART and human antibody technologies. There 
can be no assurance that competitors will not succeed in more rapidly 
developing and marketing technologies and products that are more 
effective than the products being developed by the Company or that would 
render the Company's products or technology obsolete or noncompetitive. 
Further, there can be no assurance that the Company's collaborative 
partners will not independently develop products competitive with those 
licensed to such partners by the Company, thereby reducing the 
likelihood that the Company will receive revenues under its agreements 
with such partners.

Any potential product that the Company or its collaborative 
partners succeed in developing and obtaining regulatory approval for 
must then compete for market acceptance and market share. For certain of 
the Company's potential products, an important factor will be the timing 
of market introduction of competitive products. Accordingly, the 
relative speed with which the Company and its collaborative partners can 
develop products, complete the clinical testing and approval processes, 
and supply commercial quantities of the products to the market compared 
to competitive companies is expected to be an important determinant of 
market success. For example, with respect to the speed of development of 
OST 577, the Company is aware that other drugs such as lamivudine from 
Glaxo Wellcome plc are in advanced clinical development or have been 
submitted for approval in certain jurisdictions for the treatment of CHB 
by competitive companies that have significantly greater experience and 
resources in developing antiviral products than the Company. Although 
the Company is considering clinical trials involving a combination of 
OST 577 and nucleoside analogs such as lamivudine, the availability of 
lamivudine or other drugs for the treatment of CHB could have a material 
adverse impact on the clinical development and commercial potential of 
OST 577.

Other competitive factors include the capabilities of the 
Company's collaborative partners, product efficacy and safety, timing 
and scope of regulatory approval, product availability, marketing and 
sales capabilities, reimbursement coverage, the amount of clinical 
benefit of the Company's products relative to their cost, method of 
administration, price and patent protection. There can be no assurance 
that the Company's competitors will not develop more efficacious or more 
affordable products, or achieve earlier product development completion, 
patent protection, regulatory approval or product commercialization than 
the Company. The occurrence of any of these events by the Company's 
competitors could have a material adverse effect on the business and 
financial condition of the Company. 

     Dependence on Key Personnel. The Company's success is dependent to 
a significant degree on its key management personnel. To be successful, 
the Company will have to retain its qualified clinical, manufacturing, 
scientific and management personnel. The Company faces competition for 
personnel from other companies, academic institutions, government 
entities and other organizations. There can be no assurance that the 
Company will be successful in hiring or retaining qualified personnel, 
and its failure to do so could have a material adverse effect on the 
business and financial condition of the Company.

     Potential Volatility Of Stock Price. The market for the Company's 
securities is volatile and investment in these securities involves 
substantial risk. The market prices for securities of biotechnology 
companies (including the Company) have been highly volatile, and the 
stock market from time to time has experienced significant price and 
volume fluctuations that may be unrelated to the operating performance 
of particular companies. Factors such as disappointing sales of approved 
products, approval or introduction of competing products, results of 
clinical trials, delays in manufacturing or clinical trial plans, 
fluctuations in the Company's operating results, disputes or 
disagreements with collaborative partners, market reaction to 
announcements by other biotechnology or pharmaceutical companies, 
announcements of technological innovations or new commercial therapeutic 
products by the Company or its competitors, initiation, termination or 
modification of agreements with collaborative partners, failures or 
unexpected delays in manufacturing or in obtaining regulatory approvals 
or FDA advisory panel recommendations, developments or disputes as to 
patent or other proprietary rights, loss of key personnel, litigation, 
public concern as to the safety of drugs developed by the Company, 
regulatory developments in either the U.S. or foreign countries (such as 
opinions, recommendations or statements by the FDA or FDA advisory 
panels, health care reform measures or proposals), market acceptance of 
products developed and marketed by the Company's collaborators, sales of 
the Company's common stock held by collaborative partners or insiders 
and general market conditions could result in the Company's failure to 
meet the expectations of securities analysts or investors. In such 
event, or in the event that adverse conditions prevail or are perceived 
to prevail with respect to the Company's business, the price of the 
Company's common stock would likely drop significantly. In the past, 
following significant drops in the price of a company's common stock, 
securities class action litigation has often been instituted against 
such a company. Such litigation against the Company could result in 
substantial costs and a diversion of management's attention and 
resources, which would have a material adverse effect on the Company's 
business and financial condition.




















































ITEM 6.  EXHIBITS AND REPORTS ON FORM 8-K

     (a) Exhibits - None 


     (b) No Reports on Form 8-K were filed during the quarter
          ended March 31, 1998.

















































SIGNATURE



Pursuant to the requirements of the Securities Exchange Act of 1934, the 
registrant  has duly caused this report to be signed on its be half by 
the undersigned thereunto duly authorized.


Dated:  May 14, 1998





                                              PROTEIN DESIGN LABS, INC.
                                              (Registrant)



                                              /s/ Laurence Jay Korn   

                                                  Laurence Jay Korn
                                                  Chief Executive Officer, 
                                                  Chairperson of the Board 
                                                  of Directors
                                                  (Principal Executive Officer)


                                              /s/ Jon Saxe            

                                                  Jon Saxe
                                                  President
                                                  (Chief Accounting Officer)