<PAGE>
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
-------------------
FORM 8-K/A
CURRENT REPORT
Pursuant to Section 13 or 15(d) of the
Securities and Exchange Act of 1934
Date of Report (Date of earliest event reported): December 22, 1999
Millennium Pharmaceuticals, Inc.
- -------------------------------------------------------------------------------
(Exact Name of Registrant as Specified in Charter)
<TABLE>
<S> <C> <C>
Delaware 0-28494 04-3177038
- -------------------------------------------------------------------------------------
(State or Other Jurisdiction of Incorporation) (Commission (IRS Employer
File Number) Identification No.)
75 Sidney Street, Cambridge, Massachusetts 02139
- -------------------------------------------------------------------------------------
(Address of Principal Executive Offices) (Zip Code)
</TABLE>
(617) 679-7000
- --------------------------------------------------------------------------------
(Registrant's telephone number, including area code)
Not applicable
- --------------------------------------------------------------------------------
(Former Name or Former Address, if Changed Since Last Report)
<PAGE>
ITEM 7. FINANCIAL STATEMENTS, PRO FORMA FINANCIAL INFORMATION AND EXHIBITS
FINANCIAL STATEMENTS OF BUSINESS ACQUIRED.
The previously filed Condensed Consolidated Statements of Cash Flows for
LeukoSite and subsidiary as contained in the 8K/A as filed on January 6, 2000 is
hereby modified as follows:
1. The Acquisition of ProScript-Stock issued for the nine months ended
September 30, 1999 is changed from ($2,335,028) to ($1,820,034).
2. The Acquisition of ProScript-total for the nine months ended September
30, 1999 is changed from ($104,194) to ($410,800).
- 2 -
<PAGE>
SIGNATURE
Pursuant to the requirements of the Securities Exchange Act of 1934, as amended,
the Registrant has duly caused this report to be signed on its behalf by the
undersigned hereunto duly authorized.
MILLENNIUM PHARMACEUTICALS, INC.
By:/s/ Kevin P. Starr
------------------------------
Kevin P. Starr
Chief Financial Officer
Date: January 27, 2000
- 3 -
<PAGE>
EXHIBIT INDEX
EXHIBIT NO. DESCRIPTION
23.1 Consent of Arthur Andersen LLP
- 4 -
<PAGE>
ARTHUR ANDERSEN LLP
Exhibit 23.1
CONSENT OF INDEPENDENT PUBLIC ACCOUNTANTS
As independent public accountants, we hereby consent to the incorporation of our
report dated January 29, 1999 for LeukoSite, Inc. financial statements as of
December 31, 1997 and 1998 and for the three years in the period ended December
31, 1999 included in this Form 8-K/A, into Millenium Pharmaceuticals, Inc.
previously filed Registration Statement File Nos. 333-15355, 333-15353,
333-29321, 333-15349, 333-15357, 333-29319, 333-28239, 333-84381, 333-84373, and
333-90399, 333-93397, 333-84377, and 333-93249.
/s/ Arthur Andersen LLP
Boston, Massachusetts
January 20, 2000