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                                                                     EXHIBIT 4.4


                               FOURTH AMENDMENT TO
               AMENDED AND RESTATED REGISTRATION RIGHTS AGREEMENT

                  This Fourth Amendment, dated June 13, 2001, to Amended and
Restated Registration Rights Agreement (the "Amendment") amends that certain
Amended and Restated Registration Rights Agreement dated as of October 21, 1996,
as amended pursuant to that certain First Amendment to Amended and Restated
Registration Rights Agreement dated November 30, 1999, that certain Second
Amendment to Amended and Restated Registration Rights Agreement dated February
16, 2000, and that certain Third Amendment to Amended and Restated Registration
Rights Agreement dated June 4, 2001, (the "Existing Agreement") by and among
SpectRx, Inc., a Delaware corporation (the "Company") and the holders of
Registrable Securities (as such term is defined in the Existing Agreement).

                              W I T N E S S E T H:

                  WHEREAS, the Company has determined to issue and sell to
additional purchasers as a part of the current financing to be completed by July
4, 2001, (collectively, the "Purchasers", and individually each a "Purchaser")
up to a total of 1,600,000 additional shares (the "Common Shares") of common
stock, par value $.001 per share, of the Company ("Common Stock") and warrants
to purchase an amount up to 320,000 shares (the "Warrant Shares") of Common
Stock, and as a condition to the obligation of Purchasers to purchase shares of
Common Stock, the Company will grant to Purchasers, and their successors and
assigns, certain registration rights pursuant to that certain Registration
Rights Agreement (the "RRA") of even date herewith in respect of the Common
Shares and the Warrant Shares;

                  WHEREAS, the RRA requires the Company to file a registration
statement (the "Purchasers Registration Statement") for the Common Shares and
the Warrant Shares and the Company plans to file the SAFECO Registration
Statement within 30 days of the date hereof;

                  WHEREAS, the holders of at least a majority of the Registrable
Securities for the benefit of the Company have agreed, as an inducement for the
Purchasers to invest in the Company, to waive any rights they or any other
Holder (as defined in the Existing Agreement) may have under the Existing
Agreement to include their shares in the Purchasers Registration Statement and
to amend the Existing Agreement by entering into this Amendment;

                  WHEREAS, in consideration for such waiver and amendment, the
Company has previously agreed to extend the term of the Existing Agreement by an
additional two years;
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                  NOW, THEREFORE, in consideration of the mutual promises and
other terms and conditions set forth in the Existing Agreement and this
Amendment, the parties hereto agree as follows:

                  1.       EFFECTIVENESS OF AMENDMENT. The Company and the
holders of Registrable Securities who have executed and delivered this Amendment
below acknowledge and agree that the Existing Agreement is hereby amended by
this Amendment pursuant to the provisions of Section 14 of the Existing
Agreement whereby any provision of the Existing Agreement may be amended with
the written consent of the Company and the holders of a majority of the
Registrable Securities then outstanding, and further acknowledge and agree that
such Amendment shall be binding upon each holder of Registrable Securities then
outstanding and each future holder of all Registrable Securities of the Company.

                  2.       AMENDMENT.

                           The parties hereto agree that the introductory
paragraph of Section 4(a) is hereby amended to delete the word "or" immediately
preceding "(iii)" and inserting the following immediately after the phrase "a
registration solely to a Commission Rule 145 transaction":

                  "or, (iv) a registration of securities pursuant to that
                  certain Registration Rights Agreement dated June 12, 2001 by
                  an among the Company and the Purchasers (as defined above.)"

                  3.       WAIVER. The parties hereto, for themselves and for
all other Holders, irrevocably waive any rights to include in the Purchasers
Registration Statement any shares of Common Stock owned by any of the Holders.

                         [SIGNATURES ON FOLLOWING PAGE]


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                  IN WITNESS WHEREOF, the parties have caused this Amendment to
the Existing Agreement to be duly executed and delivered by their proper and
duly authorized officers as of the date first above written.


                               SPECTRX, INC.


                               By:    /S/  Mark A. Samuels
                                  ----------------------------------------------
                               Title:  Chairman and Chief Executive Officer
                                      -------------------------------------


                               HILLMAN MEDICAL VENTURES 1993 L.P.,
                                 a Delaware limited partnership

                               By:  Hillman/Dover Limited Partnership,
                                    general partner

                               By:  Wilmington Securities, Inc.,
                                    its sole general partner

                               By:    /S/  Andrew H. McQuarrie
                                    --------------------------------------------
                               Name:       Andrew H. McQuarrie
                                     -------------------------------------------
                               Title:      Vice President
                                      ------------------------------------------


                               NORO-MOSELEY PARTNERS II, L.P.,
                                 a Georgia limited partnership

                               By:  Moseley & Company, II, L.P.
                                    general partner

                               By:    /S/  Jack K. Kelly
                                  ----------------------------------------------
                               Name:       Jack K. Kelly
                                     -------------------------------------------
                               Title:      General Partner
                                      ------------------------------------------


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