SECURITIES AND EXCHANGE COMMISSION

                             WASHINGTON, D.C. 20549

                                    FORM 8-K



                     PURSUANT TO SECTION 13 OR 15(d) OF THE
                         SECURITIES EXCHANGE ACT OF 1934
                        Date of Report: January 26, 2000


                                 MEDIMMUNE, INC.
             (Exact name of registrant as specified in its charter)



                         Commission File Number: 0-19131




                     Delaware                          52-1555759
             (State of Incorporation)              (I.R.S. Employer
                                                   Identification No.)



                35 West Watkins Mill Road, Gaithersburg, MD 20878
                (Address of principal executive office (Zip Code)


       Registrant's telephone number, including area code (301) 417-0770

                 No Exhibits are being filed with this report.


<PAGE>
ITEM 5.  OTHER EVENTS

MedImmune,  Inc.  reported  the  information  contained in the  following  press
release dated January 26, 2000.


               MEDIMMUNE SETS NEW REVENUE AND EARNINGS RECORDS

                      1999 PRODUCT SALES NEARLY DOUBLE AND
                 NET EARNINGS GROW MORE THAN NINEFOLD OVER 1998
                             (BEFORE ONE-TIME ITEMS)

Fourth Quarter Highlights
-    REVENUES GROW 55 PERCENT TO $173.7 MILLION
-    NET EARNINGS  INCREASE 149 PERCENT;  REACH $0.69 PER DILUTED  SHARE (BEFORE
     ONE-TIME ITEMS)

Gaithersburg,  MD,  January 26, 2000 --  MedImmune,  Inc.  (Nasdaq:  MEDI) today
reported a 55-percent  increase in revenues for the 1999 fourth quarter over the
same period in 1998,  excluding  one-time items and after restating 1998 amounts
to reflect the  acquisition  of U.S.  Bioscience,  Inc. Total revenues of $173.7
million in the 1999 fourth quarter  included product sales of $171.5 million and
$2.2 million in other  revenues.  Total  revenues of $112.0  million in the 1998
fourth  quarter  included  $109.0  million in product  sales and $2.9 million of
other  revenues.  The primary  growth  driver for the 1999  quarter was sales of
Synagis(R)  (palivizumab),  which totaled $151.1 million  ($147.3 million in the
United States),  a 63-percent  increase over the $92.8 million ($90.7 million in
the United States) in sales of Synagis reported in the 1998 fourth quarter. Also
contributing  to product sales for the 1999 fourth quarter were $12.4 million in
worldwide  sales of  CytoGam(R)  (Cytomegalovirus  Immune  Globulin  Intravenous
(Human))  and $6.0  million  in  revenues  from  worldwide  sales  of  Ethyol(R)
(amifostine), a drug that MedImmune acquired in its merger with U.S. Bioscience.
In the 1998 fourth  quarter,  sales of CytoGam  totaled  $9.2 million and Ethyol
revenues totaled $4.5 million.

"1999  was a year of  tremendous  growth  for  MedImmune,"  said  Dr.  Wayne  T.
Hockmeyer,  chairman and chief executive officer. "We posted another record year
of revenues and earnings,  due primarily to the growing acceptance of Synagis in
the  marketplace.  We also made significant  progress with our pipeline,  moving
three new products into the clinic,  advancing  ongoing  clinical  studies,  and
acquiring several new products through our active  in-licensing  program and the
merger with U.S. Bioscience. As a result, we begin 2000 with six products on the
market,  seven  products  in  clinical  testing,  and an array  of  early  stage
compounds for future development. We look forward to continuing to build for the
future in 2000."

ADDITIONAL FOURTH QUARTER RESULTS

Excluding One-Time Items
Net earnings for the 1999 fourth quarter grew 149 percent to $49.4  million,  or
$0.69 per  diluted  share,  from net  earnings  of $19.8  million,  or $0.30 per
diluted  share,  in the 1998 fourth  quarter.  Gross  margins in the 1999 fourth
quarter  were 77 percent  compared  to 74 percent  in the 1998  fourth  quarter.


<PAGE>

Selling,  general  and  administrative  costs rose to $41.9  million in the 1999
fourth  quarter  from $35.5  million in 1998 fourth  quarter,  due  primarily to
higher  promotion-related  expenses  for  Synagis(R),   partially  offset  by  a
settlement received for the co-promotion of RespiGam(R)  (Respiratory  Syncytial
Virus Immune Globulin  Intravenous  (Human)),  MedImmune's first generation drug
for RSV, which was largely replaced by Synagis following its launch in the third
quarter of 1998. Research and development expenses increased to $16.2 million in
the fourth  quarter  1999 from $11.9  million  in fourth  quarter  1998 due to a
larger number of active clinical trials.  Other operating  expenses decreased to
$1.1 million in fourth  quarter 1999 from $3.0 million in fourth  quarter  1998,
reflecting  decreased start-up costs for MedImmune's  manufacturing  facility in
Frederick, Maryland.

Including One-Time Items
Including   one-time   transaction   expenses   associated  with  the  completed
acquisition of U.S.  Bioscience,  Inc., net earnings for the 1999 fourth quarter
were $34.2 million, or $0.47 per diluted share. In the 1998 fourth quarter,  net
earnings were $69.3 million, or $1.02 per diluted share.  One-time items for the
1998 fourth  quarter  included a $47.4 million tax benefit for the reversal of a
valuation  allowance  for  MedImmune's  deferred  tax asset and a $12.5  million
reduction in revenues for returns of RespiGam.

ANNUAL RESULTS

For the year ended  December 31,  1999,  MedImmune  reported  revenues of $383.4
million,  a 69-percent  increase over 1998 when revenues totaled $227.2 million.
Product sales of $356.8  million  accounted for 93 percent of total  revenues in
1999 and included  $293 million in sales of Synagis,  $34.7  million in sales of
CytoGam(R),  and $19.6  million in revenues  from sales of  Ethyol(R).  In 1998,
product sales of $183.9 million included $110 million in sales of Synagis, $32.9
million  in sales of  CytoGam,  $19.8  million in sales of  RespiGam,  and $13.0
million in revenues from sales of Ethyol.

Excluding One-Time Items
Net earnings in 1999 were $68.7 million, or $0.98 per diluted share, compared to
net earnings of $7.3 million,  or $0.13 per diluted share in 1998. Gross margins
for 1999 improved to 75 percent from 64 percent in 1998,  reflecting  the higher
profit margin of Synagis,  which accounted for 82 percent of total product sales
in 1999 versus 60 percent in 1998. Selling,  general and administrative expenses
in 1999 rose to $118.2 million from $80.9 million in 1998,  primarily reflecting
increased promotional and co-promotional expenses related to Synagis, as well as
the impact of a larger organization. Research and development costs increased 41
percent in 1999 to $59.6  million  from $42.2  million in 1998,  reflecting  the
expansion of our  clinical  development  efforts for a larger  number of product
candidates. Other expenses for 1999 were $17.4 million, a decrease of 34 percent
from the previous year when other operating expenses totaled $26.2 million.

Including One-Time Items
Including one-time items, net earnings for 1999 were $93.4 million, or $1.33 per
diluted share,  compared to net earnings of $47.2 million,  or $0.73 per diluted
share in 1998.  One-time  items in 1999 were related to the  acquisition of U.S.
Bioscience.  These  one-time  items  included a tax  benefit  of $41.0  million,
accounted for in the second quarter of 1999, associated with the reversal of the
valuation  allowance on U.S.  Bioscience's  deferred tax asset, and $1.8 million
and $19.4 million of merger related costs  accounted for in the third and fourth
quarters of 1999, respectively, net of the related tax effect. The 1998 one-time
items included those discussed above for the fourth quarter of 1998, plus a


<PAGE>

$7.6 million net charge related to RespiGam(R)  inventory writedowns and a $10.3
million charge for the impact of Synagis(R) royalty buydowns.

Cash and marketable  securities at December 31, 1999 increased to $270.4 million
from $176.9  million at December 31, 1998.  During 1999,  MedImmune also reduced
its  long-term  indebtedness  to $11.9  million at December  31, 1999 from $87.9
million at December 31, 1998.

OTHER RECENT ACTIVITIES

"Besides significantly growing revenue and earnings during the fourth quarter of
1999, we also took steps to build our overall business that both diversified and
strengthened  our  core  structure,"  commented  Dr.  Hockmeyer.  "The  two  key
developments  that took place during the fourth  quarter were the  completion of
our acquisition of U.S. Bioscience,  a biotechnology company with a strong focus
in the cancer market, and the approval of our Frederick  manufacturing  facility
by the  U.S.  Food  and  Drug  Administration  for  Synagis.  Additionally,  the
international  rollout of Synagis continued to make progress during the quarter,
and we moved two new vaccine candidates into the clinic. All of these activities
are expected to help  continue  building  MedImmune  into a  profitable,  widely
diversified,  fully  integrated  biopharmaceutical  company  recognized  for its
innovation in bringing meaningful new products to market."

-    On  November  23,  1999,   MedImmune  completed  its  acquisition  of  U.S.
     Bioscience  in a  tax-free,  stock-for-stock  merger,  accounted  for  as a
     pooling of interests.  Each share of U.S. Bioscience was exchanged for 0.15
     shares of MedImmune stock.

-    In December  1999,  the FDA approved  MedImmune's  Frederick  manufacturing
     facility,  allowing the company to begin distributing  Synagis manufactured
     at that facility,  augmenting the supply of Synagis  produced at Boehringer
     Ingelheim Pharma KG in Biberach, Germany.

-    Synagis  has  received  regulatory  approval  in  28  countries,  including
     Switzerland's approval in the fourth quarter and Norway's approval in early
     January.  Additional  regulatory  approvals  are  expected in 2000,  as are
     additional   pricing  and  reimbursement   approvals  in  various  European
     countries.

-    MedImmune began Phase 1 clinical trials for two new vaccine candidates: one
     to  prevent  urinary  tract  infections  caused by E. coli and the other to
     prevent  infection  with  parvovirus  B19.  Both studies are expected to be
     completed in the second half of 2000.

Synagis(R) is a humanized  monoclonal  antibody  marketed for the  prevention of
serious lower respiratory tract disease caused by respiratory syncytial virus in
pediatric patients at high risk of RSV disease (see full prescribing information
at   www.medimmune.com/products/synagispi.htm).   Ethyol(R)  is  an  intravenous
cytoprotective  agent  marketed  for  the  reduction  of both  cumulative  renal
toxicity  associated with repeated  administration of cisplatin in patients with
advanced  ovarian cancer or non-small cell lung cancer ("NSCLC") and moderate to
severe xerostomia in patients undergoing  post-operative radiation treatment for
head and neck cancer, where the radiation port includes a substantial portion of
the    parotid     glands    (see    full     prescribing     information     at
www.usbio.com/research.htm).   CytoGam(R)  is  an  intravenous  immune  globulin
enriched in  antibodies  against  cytomegalovirus  (CMV) and is marketed for the
prophylaxis against CMV disease associated with transplantation of kidney, lung,
liver, pancreas, and heart (please see full prescribing information attached and
at www.medimmune.com/products/cytopi1.htm). RespiGam(R) is an intravenous immune
globulin  enriched in antibodies  against RSV and is marketed for the prevention
of serious lower  respiratory tract infection caused by RSV in children under 24
months of age with  bronchopulmonary  dysplasia  (BPD)


<PAGE>

or a  history  of  premature  birth  (please  see full  prescribing  information
attached and at www.medimmune.com/products/resppi.htm).

MedImmune,   Inc.  is  a  fully  integrated  biotechnology  company  focused  on
developing  and marketing  products that address  medical needs in areas such as
infectious disease, immune regulation and cancer. Headquartered in Gaithersburg,
Maryland,  MedImmune has  manufacturing  facilities  in Frederick,  Maryland and
Nijmegen,  The  Netherlands,  and an oncology  subsidiary in West  Conshohocken,
Pennsylvania.

This announcement may contain,  in addition to historical  information,  certain
forward-looking statements that involve risks and uncertainties. Such statements
reflect management's current views and are based on certain assumptions.  Actual
results could differ materially from those currently  anticipated as a result of
a  number  of  factors,  including  risks  and  uncertainties  discussed  in the
company's filings with the U.S.  Securities and Exchange  Commission.  MedImmune
cautions that RSV disease occurs primarily during the winter months; the company
believes its operating results will reflect that seasonality for the foreseeable
future.  The company is also developing  several  products for potential  future
marketing. There can be no assurance that such development efforts will succeed,
that such products will receive required  regulatory  clearance or that, even if
such regulatory clearance were received,  such products would ultimately achieve
commercial success.

                              -- Tables Follows --
<PAGE>
                                                        EXCLUDING ONE-TIME ITEMS
MEDIMMUNE, INC.
SELECTED FINANCIAL INFORMATION
(in thousands, except per share data)
<TABLE>
<CAPTION>

Condensed Consolidated Statements of Operations
                                         Three Months Ended December 31,                Year Ended December 31,
                                         -------------------------------                -----------------------
                                             1999              1998                   1999                1998
                                             ----              ----                   ----                ----
<S>                                          <C>                <C>                    <C>                 <C>
 Revenues:
     Product sales                       $ 171,459          $ 109,020 (6)         $  356,815         $    183,948
     Other                                   2,235              2,931                 26,560               43,273
                                         ---------          ---------             ----------            ---------
                                           173,694            111,951                383,375              227,221
                                         ---------          ---------             ----------            ---------

 Costs and expenses:
     Cost of sales                          39,371             28,189                 90,193               65,548 (1)
     Research and development               16,245             11,922                 59,565               42,153
     Selling, administrative and general    41,939 (7)         35,503                118,155 (7)           80,888 (2)
     Other operating expenses                1,096              3,049                 17,409               26,245 (3)
                                         ---------          ---------             ----------            ---------
                                            98,651             78,663                285,322              214,834
                                         ---------          ---------             ----------            ---------
 Interest income, net                        2,696              1,094                  9,457                5,206
                                         ---------          ---------             ----------            ---------

 Income before income taxes                 77,739             34,382                107,510               17,593
 Provision for income taxes                 28,342 (8)         14,555 (4)             38,762 (5)           10,286 (4)
                                         ---------          ---------             ----------            ---------

 Net earnings                            $  49,397          $  19,827             $   68,748           $    7,307
                                         =========          =========             ==========           ==========

Basic earnings per share                 $    0.73          $   0.34              $    1.08             $    0.13
                                         =========          ========              =========             =========


Shares used in computing
   basic earnings per share                 67,606             57,884                 63,474               56,776
                                         =========          =========             ==========           ==========

Diluted earnings per share               $    0.69          $   0.30              $    0.98             $    0.13
                                         =========          ========              =========             =========

Shares used in computing
   diluted earnings per share               71,941             68,081                 70,770               67,049
                                         =========          =========             ==========            =========

</TABLE>


The above  amounts are restated to reflect the merger with U.S.  Bioscience  and
exclude the one-time impact of significant items as follows:

(1)  The  net   impact  of  $10.4   million   related  to  the   write-down   of
     RespiGam(R)inventory following FDA approval of Synagis(R
(2)  The impact of $2.8 million  reimbursement from co-promotion partner related
     to writedown of RespiGam inventory
(3)  The impact of $10.3 million related to the buy-down of Synagis royalties
(4)  The tax benefit of $47.4  million  related to the reversal of the valuation
     allowance on the Company's  deferred tax assets and the tax benefit related
     to the other one-time charges
(5)  The tax benefit of $41.0  million  related to the reversal of the valuation
     allowance  on U.S.  Bioscience's  deferred  tax assets and the tax  benefit
     related to the other one-time charges
(6)  The impact of $12.5  million  related to returns of RespiGam  following the
     launch of Synagis
(7)  The  impact of merger  and  severance  related  costs  associated  with the
     acquisition  of U.S.  Bioscience of $21.2 million and $19.4 million for the
     year ended and the quarter ended December 31, 1999, respectively
(8)  The impact of the tax benefit  related to the merger and severance  related
     costs associated with the acquisition of U.S. Bioscience




<PAGE>


                                                        INCLUDING ONE-TIME ITEMS
MEDIMMUNE, INC.
SELECTED FINANCIAL INFORMATION
(in thousands, except per share data)

<TABLE>
<CAPTION>

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS
-----------------------------------------------
                                     Three Months Ended December 31,                    Year Ended December 31,
                                           1999                1998                    1999                 1998
                                     --------------       -------------              ------                ------
<S>                                          <C>                <C>                   <C>                    <C>

 Revenues:
     Product sales                       $ 171,459          $  96,540             $  356,815         $    183,948
     Other                                   2,235              2,931                 26,560               43,273
                                         ---------          ---------             ----------            ---------
                                           173,694             99,471                383,375              227,221
                                         ---------          ---------             ----------            ---------

 Costs and expenses:
     Cost of sales                          39,371             28,189                 90,193               75,960
     Research and development               16,245             11,922                 59,565               42,153
     Selling, administrative and general    61,373             35,503                139,389               78,060
     Other operating expenses                1,096              3,049                 17,409               36,495
                                         ---------          ---------             ----------            ---------
                                           118,085             78,663                306,556              232,668
                                         ---------          ---------             ----------            ---------
 Interest income, net                        2,696              1,094                  9,457                5,206
                                         ---------          ---------             ----------            ---------

 Income (loss) before income taxes          58,305             21,902                 86,276                 (241)
Provision (benefit) for income taxes        24,154            (47,428)                (7,095)             (47,428)
                                         ---------          ----------            -----------           ----------

 Net earnings                             $ 34,151           $ 69,330             $   93,371          $    47,187
                                         =========          =========             ==========           ==========


Basic earnings per share                 $    0.51          $   1.20              $    1.47             $    0.83
                                         =========          ========              =========             =========


Shares used in computing
   basic earnings per share                 67,606             57,884                 63,474               56,776
                                         =========          =========             ==========            =========

Diluted earnings per share               $    0.47          $   1.02              $    1.33             $    0.73
                                         =========          ========              =========              =========


Shares used in computing
   diluted earnings per share               71,941             68,081                 70,770               67,049
                                         =========          =========             ==========            =========
</TABLE>


<PAGE>


<TABLE>
<CAPTION>

CONDENSED CONSOLIDATED BALANCE SHEETS
-------------------------------------
                                                                                  December 31,          December 31,
                                                                                      1999                  1998
                                                                                 -------------         --------------
<S>                                                                                    <C>                  <C>
Assets:
     Cash and marketable securities                                               $  270,394         $    176,860
     Trade and contract receivables, net                                              87,780               36,503
     Inventory, net                                                                   35,996               27,581
     Deferred taxes, net                                                             152,122               77,518
     Property and equipment, net                                                      87,452               80,256
     Other assets                                                                     14,680                7,059
                                                                                  ----------            ---------
                                                                                  $  648,424         $    405,777
                                                                                  ==========         ============
Liabilities and shareholders' equity:
     Accounts payable                                                             $    2,995           $    4,798
     Accrued expenses                                                                 93,827               59,970
     Other liabilities                                                                 2,667                4,533
     Long term debt                                                                   11,856               87,910
     Shareholders' equity                                                            537,079              248,566
                                                                                  ----------            ---------
                                                                                  $  648,424         $    405,777
                                                                                  ==========         ============
Common shares outstanding                                                             67,947               58,309
                                                                                  ==========            =========
</TABLE>

Prior period amounts have been restated to conform with the current presentation
and to reflect the merger with U.S. Bioscience.
<PAGE>
                                   SIGNATURES

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

                                          MEDIMMUNE, INC.
                                          ---------------
                                          (Registrant




Date: January 31, 2000                    By:___________________________
                                             David M. Mott, Vice Chairman and
                                             Chief Financial Officer
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SECURITIES AND EXCHANGE COMMISSION

                             WASHINGTON, D.C. 20549

                                    FORM 8-K

                     PURSUANT TO SECTION 13 OR 15(d) OF THE
                         SECURITIES EXCHANGE ACT OF 1934
                        Date of Report: January 26, 2000

                                 MEDIMMUNE, INC.
             (Exact name of registrant as specified in its charter)

                         Commission File Number: 0-19131

                     Delaware                          52-1555759
             (State of Incorporation)              (I.R.S. Employer
                                                   Identification No.)

                35 West Watkins Mill Road, Gaithersburg, MD 20878
                (Address of principal executive office (Zip Code)

       Registrant's telephone number, including area code (301) 417-0770

                 No Exhibits are being filed with this report.
ITEM 5.  OTHER EVENTS

MedImmune,  Inc.  reported  the  information  contained in the  following  press
release dated January 26, 2000.

               MEDIMMUNE SETS NEW REVENUE AND EARNINGS RECORDS

                      1999 PRODUCT SALES NEARLY DOUBLE AND
                 NET EARNINGS GROW MORE THAN NINEFOLD OVER 1998
                             (BEFORE ONE-TIME ITEMS)

Fourth Quarter Highlights
-    REVENUES GROW 55 PERCENT TO $173.7 MILLION
-    NET EARNINGS  INCREASE 149 PERCENT;  REACH $0.69 PER DILUTED  SHARE (BEFORE
     ONE-TIME ITEMS)

Gaithersburg,  MD,  January 26, 2000 --  MedImmune,  Inc.  (Nasdaq:  MEDI) today
reported a 55-percent  increase in revenues for the 1999 fourth quarter over the
same period in 1998,  excluding  one-time items and after restating 1998 amounts
to reflect the  acquisition  of U.S.  Bioscience,  Inc. Total revenues of $173.7
million in the 1999 fourth quarter  included product sales of $171.5 million and
$2.2 million in other  revenues.  Total  revenues of $112.0  million in the 1998
fourth  quarter  included  $109.0  million in product  sales and $2.9 million of
other  revenues.  The primary  growth  driver for the 1999  quarter was sales of
Synagis(R)  (palivizumab),  which totaled $151.1 million  ($147.3 million in the
United States),  a 63-percent  increase over the $92.8 million ($90.7 million in
the United States) in sales of Synagis reported in the 1998 fourth quarter. Also
contributing  to product sales for the 1999 fourth quarter were $12.4 million in
worldwide  sales of  CytoGam(R)  (Cytomegalovirus  Immune  Globulin  Intravenous
(Human))  and $6.0  million  in  revenues  from  worldwide  sales  of  Ethyol(R)
(amifostine), a drug that MedImmune acquired in its merger with U.S. Bioscience.
In the 1998 fourth  quarter,  sales of CytoGam  totaled  $9.2 million and Ethyol
revenues totaled $4.5 million.

"1999  was a year of  tremendous  growth  for  MedImmune,"  said  Dr.  Wayne  T.
Hockmeyer,  chairman and chief executive officer. "We posted another record year
of revenues and earnings,  due primarily to the growing acceptance of Synagis in
the  marketplace.  We also made significant  progress with our pipeline,  moving
three new products into the clinic,  advancing  ongoing  clinical  studies,  and
acquiring several new products through our active  in-licensing  program and the
merger with U.S. Bioscience. As a result, we begin 2000 with six products on the
market,  seven  products  in  clinical  testing,  and an array  of  early  stage
compounds for future development. We look forward to continuing to build for the
future in 2000."

ADDITIONAL FOURTH QUARTER RESULTS

Excluding One-Time Items
Net earnings for the 1999 fourth quarter grew 149 percent to $49.4  million,  or
$0.69 per  diluted  share,  from net  earnings  of $19.8  million,  or $0.30 per
diluted  share,  in the 1998 fourth  quarter.  Gross  margins in the 1999 fourth
quarter  were 77 percent  compared  to 74 percent  in the 1998  fourth  quarter.
Selling,  general  and  administrative  costs rose to $41.9  million in the 1999
fourth  quarter  from $35.5  million in 1998 fourth  quarter,  due  primarily to
higher  promotion-related  expenses  for  Synagis(R),   partially  offset  by  a
settlement received for the co-promotion of RespiGam(R)  (Respiratory  Syncytial
Virus Immune Globulin  Intravenous  (Human)),  MedImmune's first generation drug
for RSV, which was largely replaced by Synagis following its launch in the third
quarter of 1998. Research and development expenses increased to $16.2 million in
the fourth  quarter  1999 from $11.9  million  in fourth  quarter  1998 due to a
larger number of active clinical trials.  Other operating  expenses decreased to
$1.1 million in fourth  quarter 1999 from $3.0 million in fourth  quarter  1998,
reflecting  decreased start-up costs for MedImmune's  manufacturing  facility in
Frederick, Maryland.

Including One-Time Items
Including   one-time   transaction   expenses   associated  with  the  completed
acquisition of U.S.  Bioscience,  Inc., net earnings for the 1999 fourth quarter
were $34.2 million, or $0.47 per diluted share. In the 1998 fourth quarter,  net
earnings were $69.3 million, or $1.02 per diluted share.  One-time items for the
1998 fourth  quarter  included a $47.4 million tax benefit for the reversal of a
valuation  allowance  for  MedImmune's  deferred  tax asset and a $12.5  million
reduction in revenues for returns of RespiGam.

ANNUAL RESULTS

For the year ended  December 31,  1999,  MedImmune  reported  revenues of $383.4
million,  a 69-percent  increase over 1998 when revenues totaled $227.2 million.
Product sales of $356.8  million  accounted for 93 percent of total  revenues in
1999 and included  $293 million in sales of Synagis,  $34.7  million in sales of
CytoGam(R),  and $19.6  million in revenues  from sales of  Ethyol(R).  In 1998,
product sales of $183.9 million included $110 million in sales of Synagis, $32.9
million  in sales of  CytoGam,  $19.8  million in sales of  RespiGam,  and $13.0
million in revenues from sales of Ethyol.

Excluding One-Time Items
Net earnings in 1999 were $68.7 million, or $0.98 per diluted share, compared to
net earnings of $7.3 million,  or $0.13 per diluted share in 1998. Gross margins
for 1999 improved to 75 percent from 64 percent in 1998,  reflecting  the higher
profit margin of Synagis,  which accounted for 82 percent of total product sales
in 1999 versus 60 percent in 1998. Selling,  general and administrative expenses
in 1999 rose to $118.2 million from $80.9 million in 1998,  primarily reflecting
increased promotional and co-promotional expenses related to Synagis, as well as
the impact of a larger organization. Research and development costs increased 41
percent in 1999 to $59.6  million  from $42.2  million in 1998,  reflecting  the
expansion of our  clinical  development  efforts for a larger  number of product
candidates. Other expenses for 1999 were $17.4 million, a decrease of 34 percent
from the previous year when other operating expenses totaled $26.2 million.

Including One-Time Items
Including one-time items, net earnings for 1999 were $93.4 million, or $1.33 per
diluted share,  compared to net earnings of $47.2 million,  or $0.73 per diluted
share in 1998.  One-time  items in 1999 were related to the  acquisition of U.S.
Bioscience.  These  one-time  items  included a tax  benefit  of $41.0  million,
accounted for in the second quarter of 1999, associated with the reversal of the
valuation  allowance on U.S.  Bioscience's  deferred tax asset, and $1.8 million
and $19.4 million of merger related costs  accounted for in the third and fourth
quarters of 1999, respectively, net of the related tax effect. The 1998 one-time
items included those discussed above for the fourth quarter of 1998, plus a
$7.6 million net charge related to RespiGam(R)  inventory writedowns and a $10.3
million charge for the impact of Synagis(R) royalty buydowns.

Cash and marketable  securities at December 31, 1999 increased to $270.4 million
from $176.9  million at December 31, 1998.  During 1999,  MedImmune also reduced
its  long-term  indebtedness  to $11.9  million at December  31, 1999 from $87.9
million at December 31, 1998.

OTHER RECENT ACTIVITIES

"Besides significantly growing revenue and earnings during the fourth quarter of
1999, we also took steps to build our overall business that both diversified and
strengthened  our  core  structure,"  commented  Dr.  Hockmeyer.  "The  two  key
developments  that took place during the fourth  quarter were the  completion of
our acquisition of U.S. Bioscience,  a biotechnology company with a strong focus
in the cancer market, and the approval of our Frederick  manufacturing  facility
by the  U.S.  Food  and  Drug  Administration  for  Synagis.  Additionally,  the
international  rollout of Synagis continued to make progress during the quarter,
and we moved two new vaccine candidates into the clinic. All of these activities
are expected to help  continue  building  MedImmune  into a  profitable,  widely
diversified,  fully  integrated  biopharmaceutical  company  recognized  for its
innovation in bringing meaningful new products to market."

-    On  November  23,  1999,   MedImmune  completed  its  acquisition  of  U.S.
     Bioscience  in a  tax-free,  stock-for-stock  merger,  accounted  for  as a
     pooling of interests.  Each share of U.S. Bioscience was exchanged for 0.15
     shares of MedImmune stock.

-    In December  1999,  the FDA approved  MedImmune's  Frederick  manufacturing
     facility,  allowing the company to begin distributing  Synagis manufactured
     at that facility,  augmenting the supply of Synagis  produced at Boehringer
     Ingelheim Pharma KG in Biberach, Germany.

-    Synagis  has  received  regulatory  approval  in  28  countries,  including
     Switzerland's approval in the fourth quarter and Norway's approval in early
     January.  Additional  regulatory  approvals  are  expected in 2000,  as are
     additional   pricing  and  reimbursement   approvals  in  various  European
     countries.

-    MedImmune began Phase 1 clinical trials for two new vaccine candidates: one
     to  prevent  urinary  tract  infections  caused by E. coli and the other to
     prevent  infection  with  parvovirus  B19.  Both studies are expected to be
     completed in the second half of 2000.

Synagis(R) is a humanized  monoclonal  antibody  marketed for the  prevention of
serious lower respiratory tract disease caused by respiratory syncytial virus in
pediatric patients at high risk of RSV disease (see full prescribing information
at   www.medimmune.com/products/synagispi.htm).   Ethyol(R)  is  an  intravenous
cytoprotective  agent  marketed  for  the  reduction  of both  cumulative  renal
toxicity  associated with repeated  administration of cisplatin in patients with
advanced  ovarian cancer or non-small cell lung cancer ("NSCLC") and moderate to
severe xerostomia in patients undergoing  post-operative radiation treatment for
head and neck cancer, where the radiation port includes a substantial portion of
the    parotid     glands    (see    full     prescribing     information     at
www.usbio.com/research.htm).   CytoGam(R)  is  an  intravenous  immune  globulin
enriched in  antibodies  against  cytomegalovirus  (CMV) and is marketed for the
prophylaxis against CMV disease associated with transplantation of kidney, lung,
liver, pancreas, and heart (please see full prescribing information attached and
at www.medimmune.com/products/cytopi1.htm). RespiGam(R) is an intravenous immune
globulin  enriched in antibodies  against RSV and is marketed for the prevention
of serious lower  respiratory tract infection caused by RSV in children under 24
months of age with  bronchopulmonary  dysplasia  (BPD)
or a  history  of  premature  birth  (please  see full  prescribing  information
attached and at www.medimmune.com/products/resppi.htm).

MedImmune,   Inc.  is  a  fully  integrated  biotechnology  company  focused  on
developing  and marketing  products that address  medical needs in areas such as
infectious disease, immune regulation and cancer. Headquartered in Gaithersburg,
Maryland,  MedImmune has  manufacturing  facilities  in Frederick,  Maryland and
Nijmegen,  The  Netherlands,  and an oncology  subsidiary in West  Conshohocken,
Pennsylvania.

This announcement may contain,  in addition to historical  information,  certain
forward-looking statements that involve risks and uncertainties. Such statements
reflect management's current views and are based on certain assumptions.  Actual
results could differ materially from those currently  anticipated as a result of
a  number  of  factors,  including  risks  and  uncertainties  discussed  in the
company's filings with the U.S.  Securities and Exchange  Commission.  MedImmune
cautions that RSV disease occurs primarily during the winter months; the company
believes its operating results will reflect that seasonality for the foreseeable
future.  The company is also developing  several  products for potential  future
marketing. There can be no assurance that such development efforts will succeed,
that such products will receive required  regulatory  clearance or that, even if
such regulatory clearance were received,  such products would ultimately achieve
commercial success.

                              -- Tables Follows --
EXCLUDING ONE-TIME ITEMS
MEDIMMUNE, INC.
SELECTED FINANCIAL INFORMATION
(in thousands, except per share data)
Condensed Consolidated Statements of Operations
                                         Three Months Ended December 31,                Year Ended December 31,
                                         -------------------------------                -----------------------
                                             1999              1998                   1999                1998
                                             ----              ----                   ----                ----
Revenues:
     Product sales                       $ 171,459          $ 109,020 (6)         $  356,815         $    183,948
     Other                                   2,235              2,931                 26,560               43,273
                                         ---------          ---------             ----------            ---------
                                           173,694            111,951                383,375              227,221
                                         ---------          ---------             ----------            ---------

 Costs and expenses:
     Cost of sales                          39,371             28,189                 90,193               65,548 (1)
     Research and development               16,245             11,922                 59,565               42,153
     Selling, administrative and general    41,939 (7)         35,503                118,155 (7)           80,888 (2)
     Other operating expenses                1,096              3,049                 17,409               26,245 (3)
                                         ---------          ---------             ----------            ---------
                                            98,651             78,663                285,322              214,834
                                         ---------          ---------             ----------            ---------
 Interest income, net                        2,696              1,094                  9,457                5,206
                                         ---------          ---------             ----------            ---------

 Income before income taxes                 77,739             34,382                107,510               17,593
 Provision for income taxes                 28,342 (8)         14,555 (4)             38,762 (5)           10,286 (4)
                                         ---------          ---------             ----------            ---------

 Net earnings                            $  49,397          $  19,827             $   68,748           $    7,307
                                         =========          =========             ==========           ==========

Basic earnings per share                 $    0.73          $   0.34              $    1.08             $    0.13
                                         =========          ========              =========             =========

Shares used in computing
   basic earnings per share                 67,606             57,884                 63,474               56,776
                                         =========          =========             ==========           ==========

Diluted earnings per share               $    0.69          $   0.30              $    0.98             $    0.13
                                         =========          ========              =========             =========

Shares used in computing
   diluted earnings per share               71,941             68,081                 70,770               67,049
                                         =========          =========             ==========            =========
The above  amounts are restated to reflect the merger with U.S.  Bioscience  and
exclude the one-time impact of significant items as follows:

(1)  The  net   impact  of  $10.4   million   related  to  the   write-down   of
     RespiGam(R)inventory following FDA approval of Synagis(R
(2)  The impact of $2.8 million  reimbursement from co-promotion partner related
     to writedown of RespiGam inventory
(3)  The impact of $10.3 million related to the buy-down of Synagis royalties
(4)  The tax benefit of $47.4  million  related to the reversal of the valuation
     allowance on the Company's  deferred tax assets and the tax benefit related
     to the other one-time charges
(5)  The tax benefit of $41.0  million  related to the reversal of the valuation
     allowance  on U.S.  Bioscience's  deferred  tax assets and the tax  benefit
     related to the other one-time charges
(6)  The impact of $12.5  million  related to returns of RespiGam  following the
     launch of Synagis
(7)  The  impact of merger  and  severance  related  costs  associated  with the
     acquisition  of U.S.  Bioscience of $21.2 million and $19.4 million for the
     year ended and the quarter ended December 31, 1999, respectively
(8)  The impact of the tax benefit  related to the merger and severance  related
     costs associated with the acquisition of U.S. Bioscience
INCLUDING ONE-TIME ITEMS
MEDIMMUNE, INC.
SELECTED FINANCIAL INFORMATION
(in thousands, except per share data)
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS
-----------------------------------------------
                                     Three Months Ended December 31,                    Year Ended December 31,
                                           1999                1998                    1999                 1998
                                     --------------       -------------              ------                ------
Revenues:
     Product sales                       $ 171,459          $  96,540             $  356,815         $    183,948
     Other                                   2,235              2,931                 26,560               43,273
                                         ---------          ---------             ----------            ---------
                                           173,694             99,471                383,375              227,221
                                         ---------          ---------             ----------            ---------

 Costs and expenses:
     Cost of sales                          39,371             28,189                 90,193               75,960
     Research and development               16,245             11,922                 59,565               42,153
     Selling, administrative and general    61,373             35,503                139,389               78,060
     Other operating expenses                1,096              3,049                 17,409               36,495
                                         ---------          ---------             ----------            ---------
                                           118,085             78,663                306,556              232,668
                                         ---------          ---------             ----------            ---------
 Interest income, net                        2,696              1,094                  9,457                5,206
                                         ---------          ---------             ----------            ---------

 Income (loss) before income taxes          58,305             21,902                 86,276                 (241)
Provision (benefit) for income taxes        24,154            (47,428)                (7,095)             (47,428)
                                         ---------          ----------            -----------           ----------

 Net earnings                             $ 34,151           $ 69,330             $   93,371          $    47,187
                                         =========          =========             ==========           ==========

Basic earnings per share                 $    0.51          $   1.20              $    1.47             $    0.83
                                         =========          ========              =========             =========

Shares used in computing
   basic earnings per share                 67,606             57,884                 63,474               56,776
                                         =========          =========             ==========            =========

Diluted earnings per share               $    0.47          $   1.02              $    1.33             $    0.73
                                         =========          ========              =========              =========

Shares used in computing
   diluted earnings per share               71,941             68,081                 70,770               67,049
                                         =========          =========             ==========            =========
CONDENSED CONSOLIDATED BALANCE SHEETS
-------------------------------------
                                                                                  December 31,          December 31,
                                                                                      1999                  1998
                                                                                 -------------         --------------
Assets:
     Cash and marketable securities                                               $  270,394         $    176,860
     Trade and contract receivables, net                                              87,780               36,503
     Inventory, net                                                                   35,996               27,581
     Deferred taxes, net                                                             152,122               77,518
     Property and equipment, net                                                      87,452               80,256
     Other assets                                                                     14,680                7,059
                                                                                  ----------            ---------
                                                                                  $  648,424         $    405,777
                                                                                  ==========         ============
Liabilities and shareholders' equity:
     Accounts payable                                                             $    2,995           $    4,798
     Accrued expenses                                                                 93,827               59,970
     Other liabilities                                                                 2,667                4,533
     Long term debt                                                                   11,856               87,910
     Shareholders' equity                                                            537,079              248,566
                                                                                  ----------            ---------
                                                                                  $  648,424         $    405,777
                                                                                  ==========         ============
Common shares outstanding                                                             67,947               58,309
                                                                                  ==========            =========
Prior period amounts have been restated to conform with the current presentation
and to reflect the merger with U.S. Bioscience.
SIGNATURES

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

                                          MEDIMMUNE, INC.
                                          ---------------
                                          (Registrant

Date: January 31, 2000                    By:___________________________
                                             David M. Mott, Vice Chairman and
                                             Chief Financial Officer