EXHIBIT 10.20
 
THIS NOTE HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED
(THE “ACT”), OR APPLICABLE STATE SECURITIES LAWS AND MAY NOT BE TRANSFERRED OR
OTHERWISE DISPOSED OF UNLESS IT HAS BEEN REGISTERED UNDER THE ACT AND SUCH LAWS
OR (1) REGISTRATION UNDER APPLICABLE STATE SECURITIES LAWS IS NOT REQUIRED, AND
(2) AN OPINION OF COUNSEL SATISFACTORY TO THE COMPANY IS FURNISHED TO THE
COMPANY TO THE EFFECT THAT REGISTRATION UNDER THE ACT IS NOT REQUIRED.
 
ORGANIC FARM MARKETING, LLC
 
SECURED PROMISSORY NOTE
 
December 18, 2007
Thorp, Wisconsin
 
ORGANIC FARM MARKETING, LLC, a Wisconsin limited liability company (the
“Company”), for value received, hereby promises to pay to the order of ADVANCED
BIOTHERAPY, INC., a Delaware corporation (“Advanced Biotherapy,” together with
its successors and permitted assigns, the “Holder”), (i) the aggregate amount
(“principal”) of all loans, advances and payments of any type whatsoever,
including, without limitation, payments of fees, expenses and costs, made by or
on behalf of Holder to The Northern Trust Company (the “Bank”) of Chicago,
Illinois, in connection with the Pledge Agreement entered into by Advanced
Biotherapy in favor of such Bank, or made by Advanced Biotherapy to or for the
benefit of the Company whether for the Bank or otherwise, and (ii) to pay
interest (computed on the basis of actual days elapsed in a 365-day year) on the
unpaid principal balance of each advance from the date of such advance at a rate
per annum equal to fifteen percent (15%) (such principal and accrued interest
together shall be known as the “Principal Sum”). Interest shall be payable
quarterly in arrears commencing on January 17, 2008, and continuing on each
April 17, July 17, October 17 and January 17 thereafter until the maturity date
set forth below; provided, however, that the Company may, at its option, in lieu
of making any cash payment of interest as contemplated herein, by written notice
to the Holder given not less than three (3) days prior to the interest payment
date, elect to add the interest installment to the outstanding principal balance
of this Note. If any interest installment is not paid hereunder when due, the
Holder may, at its option, elect to add such interest installment to the
outstanding principal balance of the Note or treat such failure as an Event of
Default.
 
The Principal Sum shall be payable in full on May 17, 2009, except as otherwise
provided herein. Amounts advanced under this Note and repaid may not be redrawn.
 
If the Principal Sum is not paid in full on the due date thereof (whether by
maturity or acceleration), and upon and during the continuance of any Event of
Default (as defined herein), the Principal Sum (to the extent permitted by
applicable law) shall bear interest thereafter at a rate per annum equal to
eighteen percent (18%) until such payment is paid in full or such Event of
Default is cured or waived.
 
Notwithstanding any provision of this Note to the contrary: (i) in no event
shall the interest rate on this Note be a rate per annum in excess of the
maximum interest rate permissible under applicable law, and (ii) to the extent
that interest (or other amounts paid pursuant to this Note that are deemed to be
interest under applicable law) results in interest payments in excess of those
permitted under applicable law, such excess payments shall be applied first to
the payment of the unpaid Principal Sum, second to the payment of any other
amounts due from the Company to the Holder, and third, if no other obligations
are owing to the Holder, then refunded to the Company. The Company agrees that
if such excess payments are applied in the manner provided for in this
paragraph, then to the fullest extent permitted by applicable law, the Holder
shall not be subject to any penalty provided for by any applicable law relating
to charging or collecting interest in excess of that permitted by applicable
law.
 
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The unpaid principal balance of this Note together with all interest accrued
thereon shall, at the option of the Holder, become immediately due and payable
upon any of the following events (each, an “Event of Default”):
 
(i) The Company shall default in the payment of interest or principal hereunder
and such default shall continue for a period of five (5) days;
 
(ii) Any representation or warranty made by the Company in this Note, the
Investment Agreement dated as of December 18, 2007 (“Investment Agreement”)
between the Company and Advanced Biotherapy, or any other document executed in
connection therewith, including, without limitation, the Convertible Note issued
by the Company in favor of Advanced Biotherapy and the Reimbursement Agreement
between the Company and Advanced Biotherapy (collectively, the “Related
Documents”), proves to have been untrue, incomplete or misleading in any
material respect when made or when deemed to have been made (including, but not
limited to, upon any advance hereunder);
 
(iii) The Company fails to observe or perform any covenant or agreement set
forth in this Note, the Investment Agreement or the Related Documents and, if
such failure is capable of being cured and is not otherwise subject to a cure
period under the applicable document, shall continue for a period of thirty (30)
days;
 
(iv) (I) The Company shall commence any case, proceeding or other action
(A) under any existing or future law of any jurisdiction, domestic or foreign,
relating to bankruptcy, insolvency, reorganization or relief of debtors, seeking
to have an order for relief entered with respect to it, or seeking to adjudicate
it a bankrupt or insolvent, or seeking arrangement, adjustment, composition or
other relief with respect to its debts, or (B) seeking appointment of a
receiver, trustee, custodian or other similar official for it or for all or any
substantial part of its assets, or the Company shall make a general assignment
for the benefit of its creditors; (II) there shall be commenced against the
Company any case, proceeding or other action of the nature referred to in clause
(I), above, which (A) results in the order of an order for relief or any such
adjudication or appointment, or (B) remains undismissed, undischarged or
unbonded for a period of sixty (60) days; (III) there shall be commenced against
the Company any case, proceeding or other action seeking issuance of a warranty
of attachment, execution, distraint or similar process against all or any
substantial part of its assets which results in the entry of an order for any
such relief which shall not have been vacated, discharged, or stayed or bonded
pending appeal within sixty (60) days from the entry thereof; (IV) the Company
shall take any action or furtherance of, or indicating its consent to, approval
of, or acquiescence in, any of the acts set forth in clauses (I), (II), or
(III), above; or (V) the Company shall generally not, or shall be unable to, or
shall admit in writing its inability to, pay its debts as they become due;

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(v) The occurrence of any of the following: (I) an event or series of events by
which any person, entity or group of persons or entities who are not holders of
the Company’s Units on the date of this Note shall, as a result of a tender or
exchange offer, open market purchases, privately negotiated purchases, merger,
consolidation or otherwise, have become the beneficial owner (within the meaning
of Rule 13d-3 under the Securities Exchange Act of 1934), of more than fifty
percent (50%) of the Units of the Company at any time outstanding entitled to
vote generally in the election of the Company’s directors; (II) the Company is
merged with or into another entity with the effect that immediately after such
transaction the equity owners of the Company immediately prior to such
transaction hold less than a majority of the equity interests entitled to vote
generally in the election of the directors of the entity surviving the
transaction; or (III) the direct or indirect sale, lease, exchange or other
transfer of all or substantially all of the assets of the Company;
 
(vi) A final judgment or judgments is or are entered against the Company in the
aggregate amount of One Hundred Thousand Dollars ($100,000) or more on a claim
or claims not covered by insurance;
 
(vii) This Note, the Investment Agreement or any of the Related Documents shall
be declared invalid, void or unenforceable, or the validity or enforceability
thereof shall be contested or challenged by the Company, or any determination of
partial invalidity, voidness or unenforceability shall be made which would,
individually or in the aggregate, materially reduce the principal benefits of
any provision of this Note, the Investment Agreement or any of the Related
Documents to the Holder, or make the remedies generally afforded thereby
inadequate for the practical realization thereof; or
 
(viii) The holder of any indebtedness owed by the Company in excess of
Seventy-Five Thousand Dollars ($75,000) accelerates the payment of such
indebtedness for any reason or the Company defaults in the payment of any
indebtedness with an unpaid principal amount in excess of Seventy-Five Thousand
Dollars ($75,000), and such default remains unremedied beyond the applicable
grace period therefor.
 
All payments on or in respect of this Note, including principal, interest and
premium thereon, shall be made in such coin and currency of the United States of
America as at the time of payment is legal tender for the payment of public and
private debts by check mailed and addressed to the registered holder hereof at
the address shown in the register maintained by the Company for such purpose,
or, at the option of the Holder, in such manner and at such other place in the
United States of America as the Holder shall have designated to the Company in
writing. Whenever a payment to be made hereunder shall be due on a day which is
not a business day, such payment shall be made on the next succeeding business
day and such extension of time shall be included in the computation of the
payment of interest hereunder.
 
The Company hereby waives diligence, presentment, demand, protest and notice of
every kind whatsoever. The failure of the Holder to exercise any of its rights
hereunder in any particular instance shall not constitute a waiver of the same
or of any other right in that or any subsequent instance.
 
This Note shall be binding upon the Company, its successors and permitted
assigns, and shall inure to the benefit of the Holder, its successors and
assigns.

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The Company agrees to pay all costs of enforcement and collection, including
reasonable attorneys’ fees, upon any Event of Default hereunder.
 
The Company’s obligation under this Note are secured by a General Business
Security Agreement dated as of even date herewith in favor of Holder.
 
This Note is a contract made under and governed by, and shall be construed and
enforced in accordance with, the laws of the State of Delaware, without regard
to conflict of laws principles.
 
Miscellaneous
 
1. Notification by the Company of Certain Changes. The Company will give written
notice to the Holder at least thirty (30) days prior to the date on which the
Company closes its books or takes a record (i) with respect to any dividend or
distribution upon Units, (ii) with respect to any pro rata subscription offer to
holders of Units, or (iii) for determining rights to vote with respect to any
capital reorganization, reclassification, consolidation, merger or sale of all
or substantially all of the Company’s assets to another person or entity which
is effected in such a way that holders of Units are entitled to receive (either
directly or upon subsequent liquidation) stock, securities or assets with
respect to or in exchange for Units or any dissolution, liquidation or
winding-up of the Company.
 
2. Notices. Any notices required or permitted to be given under this Note shall
be delivered personally, by FedEx, UPS Overnight, Airborne or other nationally
recognized delivery service (with evidence of delivery), if to the Company, to
its principal office, and if to the holder of this Note, to the following
address:
 
Advanced Biotherapy, Inc.
141 West Jackson, Suite 2182
Chicago, Illinois 60604
Attention: Christopher W. Capps
   Chief Executive Officer
 
Notices shall be deemed given upon personal delivery or the date of delivery
after having been sent by reputable overnight courier with evidence of delivery.
 
3. Assignment. Subject to the requirements described in Section 5 below, the
rights and obligations of the Company and the Holder shall be binding upon and
benefit the successors, assigns and transferees of the parties.
 
4. Waiver and Amendment. No provision of this Note may be waived, amended or
modified without the prior written consent of the Company and the Holder.
 
5. Transfer of this Note or Securities Issuable Upon Conversion. With respect to
any offer, sale or other disposition of this Note, the Holder will give written
notice to the Company prior thereto, describing briefly the proposed offer, sale
or other disposition and providing a draft of an opinion of counsel for the
holder that such disposition qualifies for an exemption from registration under
applicable federal and state securities law, and if such opinion of counsel is
not reasonably satisfactory to the Company, the Company shall so notify the
holder promptly after such determination has been made. Each Note thus
transferred shall bear a legend as to the applicable restrictions on
transferability in order to ensure compliance with the Act, unless in the
opinion of counsel for the Company such legend is not required.

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6. Treatment of Note. To the extent permitted by generally accepted accounting
principles, the Company will treat, account and report this Note as debt and not
equity for accounting purposes and with respect to any returns filed with
federal, state or local tax authorities.
 
7. Note Purchase Agreement. This Note is issued pursuant to the Investment
Agreement and all capitalized terms not otherwise defined herein shall have the
same meaning ascribed to them in the Investment Agreement.
 
ORGANIC FARM MARKETING, LLC

By                         
Chad L. Pawlak, Sr., President

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