content: <PAGE>
  
                         SECURITIES AND EXCHANGE COMMISSION
  
                               Washington, D.C. 20549
  
                                      FORM 8-K
  
                                   CURRENT REPORT
  
       Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934
  
                                   March 11, 2002
  
                                   --------------
  
                  Date of Report (Date of earliest event reported)
  
                                   --------------
  
                            ESSENTIAL THERAPEUTICS, INC.
  
                                   --------------
  
                 (Exact Name of Registrant as Specified in Charter)
  
              DELAWARE                 0-28006            94-3186021
  
  ----------------------------------------------------------------------
  (State or Other Jurisdiction of    (Commission        (IRS Employer
           Incorporation)            File Number)    Identification No.)
  
                         1365 Main Street, Waltham, MA 02451
  
                  ------------------------------------------------
                 (Address of Principal Executive Offices) (Zip Code)
  
                                   (781) 647-5554
  
                (Registrant's telephone number, including area code)
  
                                   --------------
  
  <PAGE>
  
  Item 5. Other Events.
  
       On March 11, 2002, Essential Therapeutics, Inc., a Delaware corporation
  ("Essential"), and MC Merger Corp., a Delaware corporation and a wholly owned
  subsidiary of Essential ("Sub"), completed the acquisition of Maret Corporation,
  a privately held Delaware corporation also known as Maret Pharmaceuticals
  ("Maret"), pursuant to an Agreement and Plan of Merger dated as of February 28,
  2002 (the "Merger Agreement"), in which Sub merged with and into Maret with
  Maret as the surviving corporation (the "Merger").
  
       Upon the closing of the acquisition, an aggregate of 2,000,000 shares of
  Essential common stock (the "Merger Shares") were issued in exchange for the
  preferred stock of Maret and in full satisfaction of certain bonus and debt
  obligations of Maret. All of the shares of Maret common stock issued and
  outstanding immediately prior to the effectiveness of the Merger were cancelled
  and extinguished in connection with the Merger. Essential did not assume any
  options or warrants exercisable for the capital stock of Maret. At the closing
  of the Merger, ten percent of the Merger Shares were placed in escrow to be held
  pursuant to the terms of an escrow agreement for a period of one year as
  security for Maret's indemnity obligations under the Merger Agreement.
  
       The Merger Shares were issued in a transaction exempt from registration
  under the Securities Act of 1933, as amended. Under the terms of the Merger
  Agreement, Essential will file a registration statement on Form S-3 covering the
  resale by the holders of the Merger Shares. All of the Merger Shares are subject
  to a contractual lock-up arrangement whereby the Merger Shares may not be resold
  for a period of one year from March 11, 2002.
  
  Item 7. Financial Statements, Pro Forma Financial Information and Exhibits.
  
       (c)  Exhibits.
  
  Exhibit
  -------
  Number    Description
  ------    -----------
  
  2.1       Agreement and Plan of Merger, dated as of February 28, 2002, by and
            among Essential Therapeutics, Inc., MC Merger Corp., Maret Corporation
            and the Stockholder Representative, as defined therein
  
  10.1      Convertible Note and Bonus Payment Agreement, dated as of February 28,
            2002, by and among Essential Therapeutics, Inc., the Note Payees, as
            defined therein, the Management Payees, as defined therein, Maret
            Corporation and the Stockholder Representative, as defined therein
  
  10.2      Escrow Agreement, dated as of March 11, 2002, by and among Essential
            Therapeutics, Inc., the Stockholder Representative, as defined therein
            and the Escrow Agent, as defined therein
  
  99.1      Press release, dated March 12, 2002
  
  <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.
  
  Date:  March 25, 2002            ESSENTIAL THERAPEUTICS, INC.
  
  
                                   By: /s/ Paul Mellett
                                       -------------------------------------------
                                          Paul Mellett,
                                          Senior Vice President, Chief Financial
                                          Officer and Treasurer
                                          (Principal Financial Officer)
metadata_documents: [{"type": "8-K", "sequence": "1", "filename": "d8k.txt", "description": "FORM 8-K", "secsgml_size_bytes": 4784}]
metadata_filer: {"company-data": {"conformed-name": "ESSENTIAL THERAPEUTICS INC", "cik": "0001010915", "assigned-sic": "2834", "irs-number": "943186021", "state-of-incorporation": "CA", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "8-K", "act": "34", "file-number": "000-28006", "film-number": "02584691"}, "business-address": {"street1": "850 MAUDE AVE", "city": "MOUNTAIN VIEW", "state": "CA", "zip": "94043", "phone": "4154281550"}, "mail-address": {"street1": "850 MAUDE AVE", "city": "MOUNTAIN VIEW", "state": "CA", "zip": "94043"}, "former-company": {"former-conformed-name": "MICROCIDE PHARMACEUTICALS INC", "date-changed": "19960319"}}
text: SECURITIES AND EXCHANGE COMMISSION
  
                               Washington, D.C. 20549
  
                                      FORM 8-K
  
                                   CURRENT REPORT
  
       Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934
  
                                   March 11, 2002
  
                                   --------------
  
                  Date of Report (Date of earliest event reported)
  
                                   --------------
  
                            ESSENTIAL THERAPEUTICS, INC.
  
                                   --------------
  
                 (Exact Name of Registrant as Specified in Charter)
  
              DELAWARE                 0-28006            94-3186021
  
  ----------------------------------------------------------------------
  (State or Other Jurisdiction of    (Commission        (IRS Employer
           Incorporation)            File Number)    Identification No.)
  
                         1365 Main Street, Waltham, MA 02451
  
                  ------------------------------------------------
                 (Address of Principal Executive Offices) (Zip Code)
  
                                   (781) 647-5554
  
                (Registrant's telephone number, including area code)
  
                                   --------------
  Item 5. Other Events.
  
       On March 11, 2002, Essential Therapeutics, Inc., a Delaware corporation
  ("Essential"), and MC Merger Corp., a Delaware corporation and a wholly owned
  subsidiary of Essential ("Sub"), completed the acquisition of Maret Corporation,
  a privately held Delaware corporation also known as Maret Pharmaceuticals
  ("Maret"), pursuant to an Agreement and Plan of Merger dated as of February 28,
  2002 (the "Merger Agreement"), in which Sub merged with and into Maret with
  Maret as the surviving corporation (the "Merger").
  
       Upon the closing of the acquisition, an aggregate of 2,000,000 shares of
  Essential common stock (the "Merger Shares") were issued in exchange for the
  preferred stock of Maret and in full satisfaction of certain bonus and debt
  obligations of Maret. All of the shares of Maret common stock issued and
  outstanding immediately prior to the effectiveness of the Merger were cancelled
  and extinguished in connection with the Merger. Essential did not assume any
  options or warrants exercisable for the capital stock of Maret. At the closing
  of the Merger, ten percent of the Merger Shares were placed in escrow to be held
  pursuant to the terms of an escrow agreement for a period of one year as
  security for Maret's indemnity obligations under the Merger Agreement.
  
       The Merger Shares were issued in a transaction exempt from registration
  under the Securities Act of 1933, as amended. Under the terms of the Merger
  Agreement, Essential will file a registration statement on Form S-3 covering the
  resale by the holders of the Merger Shares. All of the Merger Shares are subject
  to a contractual lock-up arrangement whereby the Merger Shares may not be resold
  for a period of one year from March 11, 2002.
  
  Item 7. Financial Statements, Pro Forma Financial Information and Exhibits.
  
       (c)  Exhibits.
  
  Exhibit
  -------
  Number    Description
  ------    -----------
  
  2.1       Agreement and Plan of Merger, dated as of February 28, 2002, by and
            among Essential Therapeutics, Inc., MC Merger Corp., Maret Corporation
            and the Stockholder Representative, as defined therein
  
  10.1      Convertible Note and Bonus Payment Agreement, dated as of February 28,
            2002, by and among Essential Therapeutics, Inc., the Note Payees, as
            defined therein, the Management Payees, as defined therein, Maret
            Corporation and the Stockholder Representative, as defined therein
  
  10.2      Escrow Agreement, dated as of March 11, 2002, by and among Essential
            Therapeutics, Inc., the Stockholder Representative, as defined therein
            and the Escrow Agent, as defined therein
  
  99.1      Press release, dated March 12, 2002
  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.
  
  Date:  March 25, 2002            ESSENTIAL THERAPEUTICS, INC.
  
                                   By: /s/ Paul Mellett
                                       -------------------------------------------
                                          Paul Mellett,
                                          Senior Vice President, Chief Financial
                                          Officer and Treasurer
                                          (Principal Financial Officer)