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                                                                     Exhibit 4.2


                         CALYPTE BIOMEDICAL CORPORATION

                            1995 DIRECTOR OPTION PLAN


                           AMENDED AS OF MAY 20, 2003

         1. Purposes of the Plan.


         The purposes of this Director Option Plan are to attract and retain the
best available personnel for service as Outside Directors (as defined herein) of
the Company, to provide additional incentive to the Outside Directors of the
Company to serve as Directors, and to encourage their continued service on the
Board.

         All options granted hereunder shall be "non-statutory stock options."

         2. Definitions.

         As used herein, the following definitions shall apply:

             (a) "Board" means the Board of Directors of the Company.

             (b) "Code" means the Internal Revenue Code of 1986, as amended.

             (c) "Common Stock" means the Common Stock of the Company $0.03
          par value.

             (d) "Company" means Calypte Biomedical Corporation, a Delaware
         corporation.

              (e) "Continuous Status as a Director" means the absence of any
         interruption or termination of service as a Director.

              (f) "Director" means a member of the Board.

              (g) "Employee" means any person, including officers and
         Directors, employed by the Company or any Parent or Subsidiary of the
         Company. The payment of a Director's fee by the Company shall not be
         sufficient in and of itself to constitute "employment" by the Company.
         Any person who is not employed by the Company but who is engaged by the
         Company to render services as a consultant is not considered an
         Employee under this Plan.

              (h) "Exchange Act" means the Securities Exchange Act of 1934,
         as amended.

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                  (i) "Fair Market Value" means, as of any date, the value of
         Common Stock determined as follows:

                           (i) If the Common Stock is listed on any established
                  stock exchange or a national market system, including without
                  limitation the National Market System of the National
                  Association of Securities Dealers, Inc. Automated Quotation
                  ("NASDAQ") System, the Fair Market Value of a Share of Common
                  Stock shall be the closing sales price for such stock (or the
                  closing bid, if no sales were reported) as quoted on such
                  system or exchange (or the exchange with the greatest volume
                  of trading in Common Stock) on the date of grant, as reported
                  in The Wall Street Journal or such other source as the Board
                  deems reliable;

                           (ii) If the Common Stock is quoted on the NASDAQ
                  System (but not on the National Market System thereof) or
                  regularly quoted by a recognized securities dealer but selling
                  prices are not reported, the Fair Market Value of a Share of
                  Common Stock shall be the mean between the bid and asked
                  prices for the Common Stock on the last market trading day
                  prior to the day of determination, as reported in The Wall
                  Street Journal or such other source as the Board deems
                  reliable, or;

                           (iii) In the absence of an established market for the
                  Common Stock, the Fair Market Value thereof shall be
                  determined in good faith by the Board.

                  (j) "Immediate Family Members" means the spouse, children or
           grandchildren of the Optionee.

                  (k) "Option" means a stock option granted pursuant to the
           Plan.

                  (l) "Optioned Stock" means the Common Stock subject to an
           Option.

                  (m) "Optionee" means an Outside Director who receives an
           Option.

                  (n) "Outside Director" means a Director who is not an
           Employee.

                  (o) "Parent" means a "parent corporation", whether now or
           hereafter existing, as defined in Section 424(e) of
           the Code.

                  (p) "Plan" means this Director Option Plan.

                  (q) "Share" means a share of the Common Stock, as adjusted
           in accordance with Section 10 of the Plan.

                  (r) "Subsidiary" means a "subsidiary corporation", whether
           now or hereafter existing, as defined in Section 424(f) of the
           Internal  Revenue Code of 1986.

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                  (s) "Term of Office" means the period of time commencing with
           the date of any annual meeting of the Company's stockholders at
           which Directors are elected and the date of the next subsequent
           stockholders' meeting at which Directors are elected.

         3. Stock Subject to the Plan.


         Subject to the provisions of Section 10 of the Plan, the maximum
aggregate number of Shares which may be optioned and sold under the Plan is
2,000,000 Shares (the "Pool") of Common Stock. The Shares may be authorized but
unissued, or reacquired Common Stock.

         If an Option should expire or become unexercisable for any reason
without having been exercised in full, the unpurchased Shares which were subject
thereto shall, unless the Plan shall have been terminated, become available for
future grant under the Plan.

         4. Administration of and Grants of Options under the Plan.

                  (a) Procedure for Grants. The provisions set forth in this
         Section 4(a) shall not be amended more than once every six months,
         other than to comport with changes in the Code, the Employee Retirement
         Income Security Act of 1974, as amended, or the rules thereunder. All
         grants of Options to Outside Directors under this Plan shall be
         discretionary provided such grants are made strictly in accordance with
         the following provisions:

                           (i) The Board shall have discretionary authority to
                  determine the number of shares of Common Stock to be granted
                  to Outside Directors on the date on which each person first
                  becomes a Director.

                           (ii) The Board shall have discretionary authority to
                  determine the number of Options to be granted to each
                  re-elected Director.

                  (b) Option Grants. Each Option granted hereunder will include
         the following terms:

                           (i) The term of the Option will be ten (10) years.

                           (ii) The Option will be exercisable at any time
                  during the term of the Option to the extent that the Option
                  has become vested, regardless of whether the Optionee has
                  terminated service as a member of the Board, provided however
                  that if an Optionee is removed from the Board, the Option will
                  terminate if it is not exercised within 90 days of the date of
                  such removal, but in no event later than the expiration of the
                  ten (10) year term of the Option.

                           (iii)    The exercise price per Share will be 100%
                  of the fair market value per Share on the date of grant
                  of the Option.


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                           (iv) During the period that an Optionee serves as a
                  Director, the Option will vest monthly at a rate of 8.33% per
                  month over the twelve (12) month period commencing with the
                  date of election of the Optionee as Director. The Option will
                  vest at such rate on the first day of each month subsequent to
                  such election, provided that such Option will become vested
                  and fully exercisable on the date of the next annual meeting
                  of stockholders if such meeting occurs less than twelve months
                  after the date of the grant.

                           (v) In the event that any Option granted under the
                  Plan would cause the number of Shares subject to outstanding
                  Options plus the number of Shares previously purchased under
                  Options to exceed the Pool, then the remaining Shares
                  available for Option grant shall be granted under Options to
                  the Outside Directors on a pro rata basis. No further grants
                  shall be made until such time, if any, as additional Shares
                  become available for grant under the Plan through action of
                  the Board to increase the number of Shares which may be issued
                  under the Plan; provided, further that such Options shall not
                  be exercisable until such time, if any, as the increased
                  approved by the Board is approved by the shareholders.

         5. Eligibility.


         Options may be granted only to Outside Directors; provided, however,
that if an Outside Director is nominated to the Company's Board pursuant to an
agreement between the Company and another person or entity, options granted
under the Plan may be granted to such other person(s) or entity or an affiliate
of same. All Options shall be granted in accordance with the terms set forth in
Section 4 hereof. An Outside Director who has been granted an Option may, if he
is otherwise eligible, be granted an additional Option or Options in accordance
with such provisions.

         The Plan shall not confer upon any Optionee any right with respect to
continuation of service as a Director or nomination to serve as a Director, nor
shall it interfere in any way with any rights which the Director or the Company
may have to terminate his or her directorship at any time.

         6. Term of Plan.


         The Plan shall become effective upon the earlier to occur of its
adoption by the Board or its approval by the shareholders of the Company as
described in Section 16 of the Plan. It shall continue in effect for a term of
ten (10) years unless sooner terminated under Section 11 of the Plan.

         7. Form of Consideration.


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         The consideration to be paid for the Shares to be issued upon exercise
of an Option, including the method of payment, shall consist of (i) cash, (ii)
check, (iii) delivery of a properly executed exercise notice together with such
other documentation as the Company and the broker, if applicable, shall require
to effect an exercise of the Option and delivery to the Company of the sale or
loan proceeds required to pay the exercise price, or (iv) any combination of the
foregoing methods of payment.

         8. Exercise of Option.

                  (a) Procedure for Exercise; Rights as a Shareholder. Any
         Option granted hereunder shall be exercisable at such times as are set
         forth in Section 4 hereof, provided, however, that no Options shall be
         exercisable until shareholder approval of the Plan in accordance with
         Section 16 hereof has been obtained. An Option may not be exercised for
         a fraction of a Share.


         An Option shall be deemed to be exercised when written notice of such
exercise has been given to the Company in accordance with the terms of the
Option by the person entitled to exercise the Option and full payment for the
Shares with respect to which the Option is exercised has been received by the
Company. Full payment may consist of any consideration and method of payment
allowable under Section 7 of the Plan. Until the issuance (as evidenced by the
appropriate entry on the books of the Company or of a duly authorized transfer
agent of the Company) of the stock certificate evidencing such Shares, no right
to vote or receive dividends or any other rights as a shareholder shall exist
with respect to the Optioned Stock, notwithstanding the exercise of the Option.
A share certificate for the number of Shares so acquired shall be issued to the
Optionee as soon as practicable after exercise of the Option. No adjustment will
be made for a dividend or other right for which the record date is prior to the
date the stock certificate is issued, except as provided in Section 10 of the
Plan.

         Exercise of an Option in any manner shall result in a decrease in the
number of Shares which thereafter may be available, both for purposes of the
Plan and for sale under the Option, by the number of Shares as to which the
Option is exercised.

                  (b) Rule 16b-3. Options granted to Outside Directors must
         comply with the applicable provisions of Rule 16b-3 promulgated under
         the Exchange Act or any successor thereto and shall contain such
         additional conditions or restrictions as may be required thereunder to
         qualify for the maximum exemption from Section 16 of the Exchange Act
         with respect to Plan transactions.

                  (c) Termination of Continuous Status as a Director. In the
         event an Optionee's Continuous Status as a Director terminates, the
         Optionee's vesting in his or her Options granted under this Plan will
         cease as of the date of such termination.

                  (d) Death of Optionee. In the event of an Optionee's death,
         the Optionee's estate or a person who acquired the right to exercise
         the Option by bequest or inheritance may exercise the Option to the
         extent that the Optionee was entitled to exercise it at the date of
         death (but in no event later than the expiration of its ten (10) year
         term). To the extent that the Optionee was not entitled to exercise an
         Option at the date of death, and to the extent that the Optionee's
         estate or a person who acquired the right to exercise such Option does
         not exercise such Option (to the extent otherwise so entitled) within
         the time specified herein, the Option shall terminate.


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         9. Assignment or Transfer.

                  (a) All or any portion of any Option may be transferred by an
         Optionee to (i) the Immediate Family Members of the Optionee, (ii) a
         partnership in which such Immediate Family Members are the only
         partners, or (iii) a trust or trusts for the exclusive benefit of such
         Immediate Family Members, provided that (x) there may be no
         consideration for such transfer, (y) the agreement pursuant to which
         such Options are transferred must be in a form consistent with the
         Plan, and must expressly provide for transferability in a manner
         consistent with this Section 9, and (z) subsequent transfers of
         transferred Options shall be prohibited except those by will or the
         laws of descent and distribution. Following transfer, any such Options
         shall continue to be subject to the same terms and conditions as were
         applicable immediately prior to transfer. The effect of termination of
         the Optionee's service on the Board of Directors shall continue to be
         applied with respect to the original Optionee, following which the
         Options shall be exercisable by the transferee only to the extent, and
         for the periods specified in the Plan on the occurrence of such
         termination. Neither the Company nor the administrator of the Plan
         shall have any obligation to provide the transferee with notice of
         termination of an Optionee.

                  (b) Options shall be transferable only in accordance with
         Section 9(a) or by will or the laws of descent and distribution.

         10. Adjustments Upon Changes in Capitalization, Dissolution, Merger,
         Asset Sale or Change of Control.

                  (a) Changes in Capitalization. Subject to any required action
         by the shareholders of the Company, the number of Shares covered by
         each outstanding Option and the number of Shares which have been
         authorized for issuance under the Plan but as to which no Options have
         yet been granted or which have been returned to the Plan upon
         cancellation or expiration of an Option, as well as the price per Share
         covered by each such outstanding Option, shall be proportionately
         adjusted for any increase or decrease in the number of issued Shares
         resulting from a stock split, reverse stock split, stock dividend,
         combination or reclassification of the Common Stock, or any other
         increase or decrease in the number of issued Shares effected without
         receipt of consideration by the Company; provided, however, that
         conversion of an convertible securities of the Company shall not be
         deemed to have been "effected without receipt of consideration". Except
         as expressly provided herein, no issuance by the Company of shares of
         stock of any class, or securities convertible into shares of stock of
         any class, shall affect, and no


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         adjustment by reason thereof shall be made with respect to, the number
         or price of Shares subject to an Option.


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                  (b) Dissolution or Liquidation. In the event of the proposed
         dissolution or liquidation of the Company, to the extent that an Option
         has not been previously exercised, it will terminate immediately prior
         to the consummation of such proposed action.

                  (c ) Merger or Asset Sale. In the event of a merger of the
         Company with or into another corporation, or the sale of substantially
         all of the assets of the Company, each outstanding Option shall be
         assumed or an equivalent option shall be substituted by the successor
         corporation or a Parent or Subsidiary of the successor corporation. In
         the event that the successor corporation does not agree to assume the
         Option or to substitute an equivalent option, each outstanding Option
         shall become fully vested and exercisable, including as to Shares as to
         which it would not otherwise be exercisable, unless the Board, in its
         discretion, determines otherwise. If an Optionee whose outstanding
         options have been assumed or substituted pursuant to a merger or asset
         sale is removed from the Board without cause within six months of such
         merger or asset sale, such removed director's outstanding options shall
         immediately become fully vested and exercisable. If an Option becomes
         fully vested and exercisable in the event of a merger or sale of
         assets, the Board shall notify the Optionee that the Option shall be
         fully exercisable for a period of thirty (30) days from the date of
         such notice, and the Option will terminate upon the expiration of such
         period. For the purposes of this paragraph, the Option shall be
         considered assumed if, following the merger or sale of assets, the
         option or right confers the right to purchase, for each Share of
         Optioned Stock subject to the Option immediately prior to the merger or
         sale of assets, the consideration (whether stock, cash, or other
         securities or property) received in the merger or sale of assets by
         holders of Common Stock for each Share held on the effective date of
         the transaction (and if holders were offered a choice of consideration,
         the type of consideration chosen by the holders of a majority of the
         outstanding Shares).

         11. Amendment and Termination of the Plan.

           (a) Amendment and Termination. Except as set forth in
         Section 4, the Board may at any time amend, alter, suspend, or
         discontinue the Plan, but no amendment, alteration, suspension, or
         discontinuation shall be made which would impair the rights of any
         Optionee under any grant theretofore made, without his or her consent.
         In addition, to the extent necessary and desirable to comply with Rule
         16b-3 under the Exchange Act (or any other applicable law or
         regulation), the Company shall obtain shareholder approval of any Plan
         amendment in such a manner and to such a degree as required.

                           (b) Effect of Amendment or Termination. Any such
         amendment or termination of the Plan shall not affect Options already
         granted and such Options shall remain in full force and effect as if
         this Plan had not been amended or terminated.

        12. Time of Granting Options.


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         The date of grant of an Option shall, for all purposes, be the date
determined in accordance with Section 4 hereof. Notice of the determination
shall be given to each Outside Director to whom an Option is so granted within a
reasonable time after the date of such grant.

        13. Conditions Upon Issuance of Shares.

         Shares shall not be issued pursuant to the exercise of an Option unless
the exercise of such Option and the issuance and delivery of such Shares
pursuant thereto shall comply with all relevant provisions of law, including,
without limitation, the Securities Act of 1933, as amended, the Exchange Act,
the rules and regulations promulgated thereunder, state securities laws, and the
requirements of any stock exchange upon which the Shares may then be listed, and
shall be further subject to the approval of counsel for the Company with respect
to such compliance.

         As a condition to the exercise of an Option, the Company may require
the person exercising such Option to represent and warrant at the time of any
such exercise that the Shares are being purchased only for investment and
without any present intention to sell or distribute such Shares, if, in the
opinion of counsel for the Company, such a representation is required by any of
the aforementioned relevant provisions of law.

         Inability of the Company to obtain authority from any regulatory body
having jurisdiction, which authority is deemed by the Company's counsel to be
necessary to the lawful issuance and sale of any Shares hereunder, shall relieve
the Company of any liability in respect of the failure to issue or sell such
Shares as to which such requisite authority shall not have been obtained.

        14. Reservation of Shares.

         The Company, during the term of this Plan, will at all times reserve
and keep available such number of Shares as shall be sufficient to satisfy the
requirements of the Plan.

        15. Option Agreement.

         Options shall be evidenced by written option agreements in such form as
the Board shall approve.

        16. Shareholder Approval.

         Continuance of the Plan shall be subject to approval by the
shareholders of the Company at or prior to the first annual meeting of
shareholders held subsequent to the granting of an Option hereunder. Such
shareholder approval shall be obtained in the degree and manner required under
applicable state and federal law.


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