##### 



EXHIBIT 99.1

Biogen, Inc.Biogen Savings Plan
Financial Statements and Supplemental Schedules
December 31, 2002 and 2001





---



##### 



---

Biogen, Inc.
Biogen Savings Plan
Index to Financial Statements and Supplemental Schedules

---

|                                                                                                           |                                                                                                     |  |      |    | 
|---------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------- |  | ---- | -- | 
|                                                                                                           |                                                                                                     |  | Page
|                                                                                                           |                                                                                                     |  |     
|Report of Independent Auditors                                                                             |                                                                                                     |  | 1    |   
|                                                                                                          
|Statement of Assets Available for Plan Benefits as of December 31, 2002 and 2001                           |                                                                                                     |  | 2    |   
|                                                                                                          
|Statements of Changes in Assets Available for Plan Benefits for the Years Ended
December 31, 2002 and 2001 |                                                                                                     |  | 3    |   
|                                                                                                          
|Notes to Financial Statements                                                                              |                                                                                                     |  | 4-8  |   
|                                                                                                          
|Supplemental Schedules*:                                                                                   |                                                                                                     |  |      |   
|                                                                                                          
|                                                                                                           | Schedule I  Schedule of Assets Held for Investment Purposes at End of Year
as of December 31, 2002 |  |      | 9  | 
|                                                                                                          
|                                                                                                           | Schedule II  Schedule of Reportable Transactions for the
Year Ended December 31, 2002              |  |      | 10 | 



---

|* |  | Other schedules have been omitted because such schedules are not
applicable.
|- |  | ----------------------------------------------------------------------------





---



##### 



---

Report of Independent Auditors

To the Participants and Administrator
of the Biogen Savings Plan

In our opinion, the accompanying statements of assets available for plan
benefits and the related statements of changes in assets available for plan
benefits present fairly, in all material respects, the assets available for
plan benefits of the Biogen Savings Plan (the Plan) at December 31, 2002 and
2001, and the changes in assets available for plan benefits for the years then
ended in conformity with accounting principles generally accepted in the United
States of America. These financial statements are the responsibility of the
Plans management; our responsibility is to express an opinion on these
financial statements based on our audits. We conducted our audits of these
statements in accordance with auditing standards generally accepted in the
United States of America, which require that we plan and perform the audit to
obtain reasonable assurance about whether the financial statements are free of
material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements, assessing
the accounting principles used and significant estimates made by management,
and evaluating the overall financial statement presentation. We believe that
our audits provide a reasonable basis for our opinion.

Our audits were conducted for the purpose of forming an opinion on the basic
financial statements taken as a whole. The Supplemental Schedules I and II are
presented for the purpose of additional analysis and are not a required part of
the basic financial statements but are supplementary information required by
the Department of Labors Rules and Regulations for Reporting and Disclosure
under the Employee Retirement Income Security Act of 1974. These supplemental
schedules are the responsibility of the Plans management. The supplemental
schedules have been subjected to the auditing procedures applied in the audits
of the basic financial statements and, in our opinion, are fairly stated in all
material respects in relation to the basic financial statements taken as a
whole.

PricewaterhouseCoopers LLP
Boston, Massachusetts
June 24, 2003





---



##### 



---

Biogen, Inc.
Biogen Savings Plan
Statement of Assets Available for Plan Benefits
December 31, 2002 and 2001

---

|                                   |                                     |                                                  |                               |         |            |            |            |         |            |            | 
|---------------------------------- | ----------------------------------- | ------------------------------------------------ | ----------------------------- | ------- | ---------- | ---------- | ---------- | ------- | ---------- | ---------- | 
|                                   |                                     |                                                  |                               |         | 2002       |            | 2001      
|                                   |                                     |                                                  |                               |         |            |            |           
|Assets                             |                                     |                                                  |                               |         |            |            |            |        
|Investments at fair value:         |                                     |                                                  |                               |         |            |            |            |        
|                                   | Mutual funds:                       |                                                  |                               |         |            |            |            |         |           
|                                   |                                     | Fidelity Intermediate Bond Fund                  |                               | $       | 2,330,731  |            |            | $       | 1,632,995  |           
|                                   |                                     | Fidelity Puritan Fund                            |                               |         | 6,186,866  | *          |            |         | 6,014,678  | *         
|                                   |                                     | Fidelity Value Fund                              |                               |         | 3,051,316  |            |            |         | 1,847,441  |           
|                                   |                                     | Fidelity Magellan Fund                           |                               |         | 9,560,580  | *          |            |         | 11,541,258 | *         
|                                   |                                     | Fidelity Retirement Government Money Market Fund |                               |         | 3,238,488  | *          |            |         | 2,560,667  |           
|                                   |                                     | Fidelity Growth Company Fund                     |                               |         | 9,153,780  | *          |            |         | 13,015,719 | *         
|                                   |                                     | Fidelity International Growth & Income Fund      |                               |         |           |            |            |         | 6,389      |           
|                                   |                                     | Fidelity Asset Manager Growth Fund               |                               |         | 1,851,296  |            |            |         | 1,601,223  |           
|                                   |                                     | Spartan US Equity Index Fund                     |                               |         | 4,044,754  | *          |            |         | 4,224,140  | *         
|                                   |                                     | Spartan International Index Fund                 |                               |         | 254,771    |            |            |         | 106,032    |           
|                                   |                                     | Fidelity US Bond Index Fund                      |                               |         | 2,524,368  |            |            |         | 1,320,628  |           
|                                   |                                     | Fidelity Low-Priced Stock Fund                   |                               |         | 3,392,689  | *          |            |         | 1,986,433  |           
|                                   |                                     | USAA International Fund                          |                               |         | 985,493    |            |            |         | 776,856    |           
|                                   |                                     | Janus Worldwide Fund                             |                               |         | 2,510,777  |            |            |         | 2,958,086  |           
|                                   |                                     |                                                  |                               |         |            |            |            |        
|                                   |                                     |                                                  | Total mutual funds            |         |            | 49,085,909 |            |         |            | 49,592,545 | 
|                                   |                                     |                                                  |                               |         |            |            |            |        
|                                   | Biogen, Inc. Stock Fund:            |                                                  |                               |         |            |            |            |         |           
|                                   |                                     | Biogen, Inc. common stock                        |                               |         | 11,031,082 | *          |            |         | 15,618,183 | *         
|                                   |                                     | Interest bearing cash                            |                               |         | 270,107    |            |            |         | 351,311    |           
|                                   |                                     |                                                  |                               |         |            |            |            |        
|                                   |                                     |                                                  | Total Biogen, Inc. Stock Fund |         |            | 11,301,189 |            |         |            | 15,969,494 | 
|                                   |                                     |                                                  |                               |         |            |            |            |        
|                                   | Loans to participants               |                                                  |                               | 669,578 |            |            |            | 803,217 |           
|                                   |                                     |                                                  |                               |         |            |            |            |        
|                                   |                                     |                                                  | Total investments             |         |            | 61,056,676 |            |         |            | 66,365,256 | 
|                                   |                                     |                                                  |                               |         |            |            |            |        
|Receivables:                       |                                     |                                                  |                               |         |            |            |            |        
|                                   | Investment income receivable        |                                                  |                               | 297     |            |            |            | 1,113   |           
|                                   | Participant contribution receivable |                                                  |                               | 359,508 |            |            |            |        |           
|                                   | Employer contribution receivable    |                                                  |                               | 52,425  |            |            |            |        |           
|                                   |                                     |                                                  |                               |         |            |            |            |        
|                                   |                                     |                                                  | Total receivables             |         |            | 412,230    |            |         |            | 1,113      | 
|                                   |                                     |                                                  |                               |         |            |            |            |        
|Assets available for plan benefits |                                     | $                                                | 61,468,906                    |         |            | $          | 66,366,369 |        
|                                   |                                     |                                                  |                               |         |            |            |            |        



---

|* |  | Represents 5% or more of assets available for plan benefits.
|- |  | ------------------------------------------------------------

The accompanying notes are an integral part of these financial statements.

2



---



##### 



---

Biogen, Inc.
Biogen Savings Plan
Statement of Changes in Assets Available for Plan Benefits
For the Years Ended December 31, 2002 and 2001

---

|                                    |                               |                                               |                           |                                       |           |             |             |            |           |            |            |  
|----------------------------------- | ----------------------------- | --------------------------------------------- | ------------------------- | ------------------------------------- | --------- | ----------- | ----------- | ---------- | --------- | ---------- | ---------- | -
|                                    |                               |                                               |                           |                                       |           | 2002        |             | 2001      
|                                    |                               |                                               |                           |                                       |           |             |             |           
|Additions:                          |                               |                                               |                           |                                       |           |             |             |           
|                                    | Investment income:            |                                               |                           |                                       |           |             |             |            |          
|                                    |                               | Net depreciation of investments:              |                           |                                       |           |             |             |            |           |           
|                                    |                               |                                               | Mutual funds              |                                       | $         | (10,790,597 | )           |            | $         | (7,353,565 | )         
|                                    |                               |                                               | Biogen, Inc. common stock |                                       |           | (4,687,429  | )           |            |           | (671,278   | )         
|                                    |                               |                                               |                           |                                       |           |             |             |           
|                                    |                               |                                               |                           | Total net depreciation of investments |           |             | (15,478,026 | )          |           |            | (8,024,843 | )
|                                    |                               |                                               |                           |                                       |           |             |             |           
|                                    | Dividends and interest:       |                                               |                           |                                       |           |             |             |            |          
|                                    |                               | Mutual funds                                  |                           |                                       | 850,100   |             |             |            | 973,943   |           
|                                    |                               | Biogen, Inc. Stock Fund interest bearing cash |                           |                                       | 5,670     |             |             |            | 19,410    |           
|                                    |                               |                                               |                           |                                       |           |             |             |           
|                                    |                               |                                               |                           | Total dividends and interest          |           |             | 855,770     |            |           |            | 993,353    |  
|                                    |                               |                                               |                           |                                       |           |             |             |           
|                                    | Contributions:                |                                               |                           |                                       |           |             |             |            |          
|                                    |                               | Employer contributions                        |                           |                                       | 1,704,806 |             |             |            | 1,223,138 |           
|                                    |                               | Participant contributions                     |                           |                                       | 9,877,885 |             |             |            | 7,357,102 |           
|                                    |                               | Participant rollovers                         |                           |                                       | 1,546,426 |             |             |            | 1,263,868 |           
|                                    |                               |                                               |                           |                                       |           |             |             |           
|                                    |                               |                                               |                           | Total contributions                   |           |             | 13,129,117  |            |           |            | 9,844,108  |  
|                                    |                               |                                               |                           |                                       |           |             |             |           
|                                    |                               |                                               |                           | Total additions (deductions)          |           |             | (1,493,139  | )          |           |            | 2,812,618  |  
|                                    |                               |                                               |                           |                                       |           |             |             |           
|Deductions:                         |                               |                                               |                           |                                       |           |             |             |           
|                                    | Benefits paid to participants |                                               |                           | 3,403,466                             |           |             |             | 2,161,046  |          
|                                    | Administrative fees           |                                               |                           | 858                                   |           |             |             | 88         |          
|                                    |                               |                                               |                           |                                       |           |             |             |           
|                                    |                               |                                               | Total deductions          |                                       |           | 3,404,324   |             |            |           | 2,161,134  |           
|                                    |                               |                                               |                           |                                       |           |             |             |           
|                                    |                               |                                               | Net increase (decrease)   |                                       |           | (4,897,463  | )           |            |           | 651,484    |           
|Assets available for plan benefits: |                               |                                               |                           |                                       |           |             |             |           
|                                    | Beginning of year             |                                               |                           | 66,366,369                            |           |             |             | 65,714,885 |          
|                                    |                               |                                               |                           |                                       |           |             |             |           
|                                    | End of year                   |                                               | $                         | 61,468,906                            |           |             | $           | 66,366,369 |          
|                                    |                               |                                               |                           |                                       |           |             |             |           

The accompanying notes are an integral part of these financial statements.

3



---



##### 



---

Biogen, Inc.
Biogen Savings Plan
Notes to Financial Statements

---



|1. |  | Description of the Plan                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
|-- |  | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|  
|   |  | The following brief description of the Biogen Savings Plan (the Plan)
is provided for general information purposes only. Participants should
refer to the Plan agreement for more complete information.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|  
|   |  | General Information
Biogen, Inc. (the Company) established the Plan as a deferred
profit-sharing plan under Section 401(a) of the Internal Revenue Code of
1986, effective January 1, 1987. The Plan is designed to allow eligible
employees to accumulate savings for retirement in the Plan without paying
income taxes until the savings are actually received.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
|  
|   |  | Administration of the Plan
The Plan is administered by a plan administrator appointed by the
Company. The Plan administrator may be an individual or a committee.
Fidelity Management Trust Company is the Plan trustee (the Trustee).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                
|  
|   |  | Participation
Participation in the Plan is voluntary. Each employee of the Company and
its subsidiaries and affiliates is eligible to participate in the Plan
upon the attainment of age 21 unless he/she is (a) a student employed on
a temporary basis, (b) an employee of a non-U.S. subsidiary or division
of the Company, or (c) a member of a collective bargaining unit. An
otherwise eligible employee who is temporarily assigned by his or her employer
to work for the Company or its subsidiaries or affiliates, or on a joint venture
with the Company outside of the United States with the intent on the
part of the employer that such employee will return to work as an
eligible employee of the employer in the United States will be treated as
an employee in the class eligible to participate in the Plan during such
temporary assignment.                                                                                                                                                      
|  
|   |  | Contributions
Eligible employees may make savings deposits (as described below) to the
Plan in whole percentages of their gross salary ranging from a minimum of
1% to a maximum of 40%, subject to certain limitations. Effective April
1, 2002, for each pay period, the Company will make matching
contributions equal in value of 25% of each employees savings deposit,
up to a maximum of 6% of the employees gross salary, subject to certain
limitations, into the same funds as selected by the participants for
their own contributions. Prior to April 1, 2002, matching contributions
were made exclusively into the Biogen Inc. Stock Fund. Following the end
of each plan year, an additional true-up matching contribution may be
made on behalf of an eligible participant who has not received the full
benefit of the Company matching contribution. Effective January 1, 2002,
eligible employees are allowed to contribute after-tax savings deposits
to the Plan, subject to certain limitations.
|  
|   |  | Participant Accounts
Fidelity Investments Institutional Operations Company, Inc. is the Plans
recordkeeper. Each participants account is credited with the
participants contribution, the Companys matching contribution and Plan
earnings. Allocations are based on participant earnings or account
balances, as defined. The benefit to which a participant is entitled is
the benefit that can be provided from the participants vested account.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                

4



---



##### 



---

Biogen, Inc.
Biogen Savings Plan
Notes to Financial Statements

---



| |  | Investment of Contributions
Effective April 1, 2002, matching contributions will be made into the
same funds as selected by the participants for their own contributions,
and not exclusively into the Biogen, Inc. Stock Fund. Prior to April 1,
2002, company matching contributions were invested exclusively in the
Biogen, Inc. Stock Fund. The Biogen, Inc. Stock Fund includes Biogen,
Inc. stock and cash or short term investments for liquidity purposes.
Employee contributions are invested at the direction of the employee in
increments of 1% in any combination of the following investment options:
| |  | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| |  |  | An intermediate bond fund designed to earn a high level of current
return. It is invested in the Fidelity Intermediate Bond Fund.                                                                                                                                       
| | - |  | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|
| |  |  | A balanced fund designed to preserve principal balance by
investing in a diversified portfolio of high yielding stocks and
bonds. It is invested in the Fidelity Puritan Fund.                                                                                          
|
| |  |  | A fund which seeks to provide capital appreciation from
investments in companies which are undervalued or which possess
valuable fixed assets. It is invested in the Fidelity Value Fund.                                                                               
|
| |  |  | An aggressive growth fund invested which seeks to achieve capital
appreciation. It is invested in the Fidelity Magellan Fund.                                                                                                                                           
|
| |  |  | A US government money market fund seeks high current earnings
while preserving capital and liquidity. It is invested in the
Fidelity Retirement Government Money Market Fund.                                                                                           
|
| |  |  | A growth company fund which seeks to provide capital appreciation
from investments primarily in common stock of companies with
above-average growth characteristics. It is invested in the
Fidelity Growth Company Fund.                                                
|
| |  |  | An international equity fund which seeks capital growth, current
income and growth of income. It is invested in the Fidelity
International Growth & Income Fund.                                                                                                        
|
| |  |  | An asset allocation fund that seeks total return with reduced risk
over the long term. It is invested in the Fidelity Asset Manager
Growth Fund.                                                                                                                        
|
| |  |  | A long term growth fund which seeks to provide investment results
that correspond to the total return performance of common stock of
companies publicly traded in the US. It is invested in the
Spartan US Equity Index Fund, a Fidelity sponsored fund.                
|
| |  |  | A fund that seeks to provide investment results that
correspond to the total return of foreign stock markets. It is
invested in the Spartan International Index Fund, a Fidelity
sponsored fund.                                                                        
|
| |  |  | A corporate bond fund that seeks to replicate the price and
interest performance of the debt securities in the Lehman Brothers
Aggregate Bond Index. It is invested in the Fidelity US Bond Index
Fund.                                                                 
|
| |  |  | A fund which seeks to provide capital appreciation from
investments in companies which are undervalued or which are out of
favor with other investors and that could offer the possibility for
significant growth. It is invested in the Fidelity Low-Priced Stock
Fund.

5



---



##### 



---

Biogen, Inc.
Biogen Savings Plan
Notes to Financial Statements

---



| |  |  | A fund that seeks long term capital growth and current income from
investments in stocks of companies organized and operating principally
outside the United States. It is invested in the USAA International
Fund.
| | - |  | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|
| |  |  | A fund that seeks capital growth over the long term from
investments in common stocks of foreign and domestic companies. It
is invested in the Janus Worldwide Fund.                                               
|
| |  |  | A fund that pools money to buy shares of Biogen, Inc. stock
and cash or short-term investments. It is invested in the Biogen,
Inc. Stock Fund.                                                                     



|   |  | Dividends, interest, and other distributions received in any fund are
reinvested in the same fund.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
|-- |  | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|  
|   |  | Vesting
Participants are fully vested in their savings deposit accounts and
rollover accounts at all times. Participants will vest in the Companys
matching contribution fully on their 55th birthday or, before then, at a rate of 25% for each year of Plan service and
will be fully vested after four years of Plan service. Participants
become 100% vested in the Companys matching contributions upon retirement
or termination of employment due to disability or death.                                                                                                                                                              
|  
|   |  | Benefit Payments
Distributions are generally payable at termination of employment due to
retirement, disability, death or any other reason. Distribution payments
are made in cash in a lump sum. At a participants election, the portion
of the participants accounts invested in the Biogen, Inc. Stock Fund
will be paid to him or her in the form of whole shares of Biogen Stock,
with the value of any fractional share paid in cash. Forfeitures of
nonvested amounts are used to reduce the amount of future Company
matching contributions.                                                                                          
|  
|   |  | Loans
Participants may borrow against their savings deposit and rollover
accounts. Loans will bear a reasonable interest rate determined by the
Company. Repayment of loans is made by direct withholdings of a
participants salary for a period not to exceed five years (ten years for
a residential loan). The minimum loan amount is $1,000 and a participant
may borrow up to a maximum of the amount in the participants savings
deposit and rollover accounts, 50% of the participants vested account
balance, or $50,000, whichever is smallest. There is no minimum service
requirement for a participant to be eligible for a loan.
|  
|   |  | Plan Amendment and Termination
The Company has the right to amend, suspend or terminate the Plan, but
may not do so in a way which would divest a participant of accrued vested
benefits. If the Plan is terminated, the Trustee will distribute the
assets held in the trust, after payment of expenses, in such a manner as
the Plan Committee shall determine. The Company currently has no
intention to terminate the Plan.                                                                                                                                                                                                                 
|  
|2. |  | Summary of Significant Accounting Policies                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
|  
|   |  | The preparation of financial statements in conformity with accounting
principles generally accepted in the United States of America requires
management to make estimates and assumptions that affect the reported
amounts and disclosures in the financial statements. Actual results
could differ from those estimates. The following is a summary of
significant accounting policies which are in conformity with accounting
principles generally accepted in the United States of America
consistently followed by the Plan in the preparation of its financial
statements.                                                                 

6



---



##### 



---

Biogen, Inc.
Biogen Savings Plan
Notes to Financial Statements

---



|   |  | Basis of Accounting
The financial statements of the Plan are prepared on the accrual basis of
accounting.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
|-- |  | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|  
|   |  | Investments
Plan investments are stated at fair value. The Company stock is valued
at its quoted market price. Mutual fund investments are valued at net
asset value representing the value of which shares of the fund may be
purchased or redeemed. Loans to participants are stated at principal
plus accrued interest, which approximates fair value.                                                                                                                                                                                                                                                 
|  
|   |  | Purchases and sales of securities are recorded on a trade-date basis.
Cost is determined on the average cost basis. Net appreciation or
depreciation, which includes realized and unrealized gains or losses on
investments, is reflected for the year in the statement of changes in
assets available for plan benefits. Interest income is recorded on the
accrual basis. Dividends are recorded on the ex-dividend date.                                                                                                                                                                               
|  
|   |  | Contributions
Employee contributions are recorded in the period in which the employee
payroll deductions are made. Matching contributions from the Company are
accrued bi-weekly and paid on the last day of the related quarter and are
allocated based upon the participants contribution selections.                                                                                                                                                                                                                                                                                                  
|  
|   |  | Payment of Benefits
Benefits are recorded when paid.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
|  
|   |  | Income Taxes
No provision for income taxes has been made in the financial statements
as the Plan qualifies as a tax-exempt entity under Section 401 of the
Internal Revenue Code (Code). The Plan has received a favorable
determination letter dated June 5, 1996 from the Internal Revenue
Service. The Plan has since been amended and a new letter has not been
requested. Management has asserted the Plan, as amended, and its
operations have been and continue to be in accordance with all applicable
provisions of the Code and the Employee Retirement Income Security Act of
1974 (ERISA).
|  
|   |  | Expenses of the Plan
Administrative and audit fees are paid directly by the Company and,
accordingly, such items are not reflected in the financial statements of
the Plan. Expenses directly related to the investment transactions of
the Plan are paid by the Plan.                                                                                                                                                                                                                                                                                                                                    
|  
|3. |  | Loans to Participants                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     
|  
|   |  | At December 31, 2002 and 2001, the Plan had loans receivable from
participants aggregating $669,578 and $803,217, respectively. Interest
rates on the loans range from 6.5% to 9.5% annually. The loans are
collateralized by the participants interest in the Plan.                                                                                                                                                                                                                                                                                                                                     

7



---



##### 



---

Biogen, Inc.
Biogen Savings Plan
Notes to Financial Statements

---



|4. |  | Party-in-Interest Transactions                                                                                                                                                                                                                                                                                                                                                                    
|-- |  | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|  
|   |  | The Plan invests in common stock of Biogen, Inc., the employer, and
transactions in this common stock are party-in-interest transactions.
During the years ended December 31, 2002 and 2001, the Plan purchased
shares of the common stock having values of $1,359,978 and $1,885,797,
respectively, and sold shares of the common stock having values of
$1,997,260 and $1,759,867, respectively.
|  
|   |  | Certain of the Plans assets are invested in mutual funds for which FMR
Corp. provides investment advisory services. FMR Corp. is an affiliate
of both Fidelity Management Trust Company and Fidelity Investments
Institutional Operations Company, Inc. Accordingly, these transactions
qualify as party-in-interest.                                                                            
|  
|5. |  | Non-participant-Directed Investment                                                                                                                                                                                                                                                                                                                                                               
|  
|   |  | Information about the assets and the significant components of the
changes in assets relating to the Biogen Stock Fund (includes both
non-participant and participant directed investments) as follows:                                                                                                                                                                                           

|        |                         |   |              |            |      |   |            |            | 
|------- | ----------------------- | - | ------------ | ---------- | ---- | - | ---------- | ---------- | 
|        |                         |   | December 31,
|        |                         |   |             
|        |                         |   | 2002         |            | 2001
|        |                         |   |              |            |     
|Assets: |                         |   |              |            |      |   |            |           
|        | Biogen, Inc. Stock Fund |   | $            | 11,301,189 |      |   | $          | 15,969,494 | 
|        | Receivables             |   |              | 297        |      |   |            | 1,113      | 
|        |                         |   |              |            |      |   |            |           
|        |                         | $ | 11,301,486   |            |      | $ | 15,970,607 |           
|        |                         |   |              |            |      |   |            |           

|                   |                                            |   |              |            |      |   |         |           |  
|------------------ | ------------------------------------------ | - | ------------ | ---------- | ---- | - | ------- | --------- | -
|                   |                                            |   | Year Ended  
|                   |                                            |   | December 31,
|                   |                                            |   |             
|                   |                                            |   | 2002         |            | 2001
|                   |                                            |   |              |            |     
|Changes in Assets: |                                            |   |              |            |      |   |         |          
|                   | Employer contributions                     |   | $            | 446,732    |      |   | $       | 1,218,822 |  
|                   | Participant contributions                  |   |              | 920,461    |      |   |         | 901,085   |  
|                   | Interest                                   |   |              | 5,670      |      |   |         | 19,410    |  
|                   | Net depreciation                           |   |              | (4,687,429 | )    |   |         | (671,278  | )
|                   | Transfer of investments from other options |   |              | (822,954   | )    |   |         | (145,541  | )
|                   | Benefits paid to participants              |   |              | (531,601   | )    |   |         | (506,029  | )
|                   |                                            |   |              |            |      |   |         |          
|                   |                                            | $ | (4,669,121   | )          |      | $ | 816,469 |          
|                   |                                            |   |              |            |      |   |         |          

8



---



##### 



|                                                                                                                                                           |                        
|---------------------------------------------------------------------------------------------------------------------------------------------------------- | -----------------------
|Biogen, Inc.
Biogen Savings Plan
Schedule of Assets Held for Investment Purposes at End of Year
(Schedule H, Part IV, Item 4i, Form 5500)December 31, 2002 | Supplemental Schedule I

---

|          |           |  |  |                                                   |  |       |           |         |  |   |            | 
|--------- | --------- |  |  | ------------------------------------------------- |  | ----- | --------- | ------- |  | - | ---------- | 
|Number of |           |  |  |                                                   |  |       |           |         |  |  
|Shares/   |           |  |  |                                                   |  |       |           | Current
|Units     |           |  |  | Cost                                              |  | Value
|          |           |  |  |                                                   |  |      
|          | 217,216   |  |  | Fidelity Intermediate Bond Fund*                  |  |       | **        |         |  | $ | 2,330,731  | 
|          | 391,822   |  |  | Fidelity Puritan Fund*                            |  |       | **        |         |  |   | 6,186,866  | 
|          | 65,775    |  |  | Fidelity Value Fund*                              |  |       | **        |         |  |   | 3,051,316  | 
|          | 121,081   |  |  | Fidelity Magellan Fund*                           |  |       | **        |         |  |   | 9,560,580  | 
|          | 3,238,488 |  |  | Fidelity Retirement Government Money Market Fund* |  |       | **        |         |  |   | 3,238,488  | 
|          | 258,435   |  |  | Fidelity Growth Company Fund*                     |  |       | **        |         |  |   | 9,153,780  | 
|          | 154,661   |  |  | Fidelity Asset Manager Growth Fund*               |  |       | **        |         |  |   | 1,851,296  | 
|          | 129,848   |  |  | Spartan U.S. Equity Index Fund*                   |  |       | **        |         |  |   | 4,044,754  | 
|          | 12,650    |  |  | Spartan International Index Fund*                 |  |       | **        |         |  |   | 254,771    | 
|          | 224,588   |  |  | Fidelity US Bond Index Fund*                      |  |       | **        |         |  |   | 2,524,368  | 
|          | 134,791   |  |  | Fidelity Low-Priced Stock Fund*                   |  |       | **        |         |  |   | 3,392,689  | 
|          | 65,135    |  |  | USAA International Fund                           |  |       | **        |         |  |   | 985,493    | 
|          | 78,144    |  |  | Janus Worldwide Fund                              |  |       | **        |         |  |   | 2,510,777  | 
|          |           |  |  |                                                   |  |       |           |         |  |   |            | 
|          |           |  |  | Total mutual funds                                |  |       |           |         |  |   | 49,085,909 | 
|          |           |  |  |                                                   |  |       |           |         |  |   |            | 
|          | 275,364   |  |  | Biogen, Inc. common stock*                        |  | $     | 8,687,721 |         |  |   | 11,031,082 | 
|          |           |  |  | Interest bearing cash                             |  |       | 270,107   |         |  |   | 270,107    | 
|          |           |  |  |                                                   |  |       |           |         |  |   |            | 
|          |           |  |  | Total Biogen, Inc. Stock Fund                     |  |       |           |         |  |   | 11,301,189 | 
|          |           |  |  |                                                   |  |       |           |         |  |   |            | 
|          |           |  |  | Loans to participants* 6.5% to 9.5%               |  |       |           |         |  |   | 669,578    | 
|          |           |  |  |                                                   |  |       |           |         |  |   |            | 
|          |           |  |  | Total                                             |  |       |           |         |  | $ | 61,056,676 | 
|          |           |  |  |                                                   |  |       |           |         |  |   |            | 



---

|*  |  | Party-in-interest.                                
|-- |  | --------------------------------------------------
|** |  | Cost omitted for participant-directed investments.

9



---



##### 



|                                                                                                                                                                                                                |                         
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------
|Biogen, Inc.
Biogen Savings Plan
Schedule of Reportable Transactions (Involving Amounts in Excess of 5% of Current Value of Plan Assets)*
(Schedule H, Part IV, Item 4j, Form 5500)Year ended December 31, 2002 | Supplemental Schedule II

---

|               |  |                           |  |       |           |          |  |         |           |          |  |         |   |            |  |             |   |  |  |   |           |  |  |   |           |          |  |   |          |   |  | 
|-------------- |  | ------------------------- |  | ----- | --------- | -------- |  | ------- | --------- | -------- |  | ------- | - | ---------- |  | ----------- | - |  |  | - | --------- |  |  | - | --------- | -------- |  | - | -------- | - |  | 
|               |  |                           |  |       |           |          |  |         |           |          |  |         |   |            |  |             |   |  |  |   |           |  |  |   |           | Current  |  |   |          |  
|               |  |                           |  |       |           |          |  |         |           |          |  |         |   |            |  |             |   |  |  |   |           |  |  |   |           | Value on |  |   |          |  
|               |  |                           |  |       |           | Purchase |  | Selling |           | Lease    |  | Expense |   | Historical |  | Transaction |   |  |  |  
|Party Involved |  | Description of Asset      |  | Price |           | Price    |  | Rental  |           | Incurred |  | Cost    |   | Date       |  | Gain (Loss)
|               |  |                           |  |       |           |          |  |         |           |          |  |         |   |            |  |            
|Biogen, Inc.   |  | Biogen, Inc. common stock |  | $     | 1,359,978 |          |  | $       |          |          |  | $       |  |            |  | $           |  |  |  | $ |          |  |  | $ | 1,359,978 |          |  | $ |         |  
|Biogen, Inc.   |  | Biogen, Inc. common stock |  |       |          |          |  |         | 1,997,260 |          |  |         |  |            |  |             |  |  |  |   | 2,653,112 |  |  |   | 1,997,260 |          |  |   | (655,852 | )



---

|* |  | Non-participant directed transactions in excess of 5% of the current
value of the Plans assets as of December 31, 2002 as defined by Section
2520.103-6 of the Department of Labors Rules and Regulations for
Reporting and Disclosure under the Employee Retirement Security Income Act
of 1974.
|- |  | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

10