Exhibit 10.1

LV ADMINISTRATIVE SERVICES, INC.

as Administrative and Collateral Agent

420 LEXINGTON AVENUE, SUITE 2840

NEW YORK, NY 10170

MAY 10, 2012

Biovest International, Inc.

324 South Hyde Park Avenue, Suite 350

Tampa, Florida 33606

Attn: Chief Executive Officer/President

Re: Sale and/or Repayment of Biovest Term Notes

Ladies and Gentlemen:

Reference is made to: (a) that certain Term Loan & Security Agreement dated as
of November 17, 2010 (as amended, supplemented, restated or modified from time
to time, the “Term Loan & Security Agreement”) by and between LV Administrative
Services, Inc. (“LV”) as Agent for and on behalf of each of Laurus Master Fund,
Ltd. (in liquidation) (“Laurus”), Erato Corporation (“Erato”), Valens Offshore
SPV I, Ltd. (“VOF”), Valens Offshore SPV II, Corp. (“VOF2”), Valens U.S. SPV I,
LLC. (“VUS”), PSource Structured Debt Limited (“PSD”) and the other creditor
parties named therein from time to time (Laurus, Erato, VOF, VOF2, VUS, PSD and
such other creditor parties, collectively, the “Lenders”) and Biovest
International, Inc. (“Biovest”); (b) Secured Term Notes A and B (the “Term
Notes”) issued on or about November 17, 2010 to the Lenders; and (c) the
Ancillary Agreements (as defined in the Term Loan & Security Agreement).
Capitalized terms used but not defined herein shall have the meanings ascribed
thereto in the Term Loan & Security Agreement or the Ancillary Agreements, as
applicable.

WHEREAS, as of November 17, 2010, (i) Laurus was issued 1,877,510 shares of
Biovest common stock, (ii) VOF was issued 7,320,877, (iii) VUS was issued
1,036,468 shares of Biovest common stock and (iv) PSD was issued 4,599,927
shares of Biovest common stock; and

WHEREAS, Biovest is seeking to arrange for one or more purchaser(s), which may
include a direct purchase by Biovest, to, acquire on or before August 15, 2012
the Term Notes and Term Loan & Security Agreement together with a large portion
of the Biovest common stock owned by certain of the Lenders and one-half of the
BiovaxID Biologic Products Royalty owned by the Lenders for an aggregate
purchase price of approximately $31 million; and

WHEREAS, pursuant to Section 42 of the Term Loan & Security Agreement, LV has
the authority to enter into this Letter Agreement modifying, amending and
waiving certain terms and provisions of the Term Loan & Security Agreement and
the Ancillary Agreements, which action will constitute the valid and binding
action on behalf of each of the Lenders, subject to their acknowledgement and
consent of same.

 

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In consideration of good and valuable consideration, the receipt and sufficiency
of which are hereby acknowledged, Biovest and LV as designated Agent for and on
behalf of the Lenders hereby agree to, and acknowledge, the following:

 

1. SALE OF THE BIOVEST TERM NOTES.

 

  A. If on or before August 15, 2012 Biovest or its designee indefeasibly pays
$30.9 million in cash to LV in purchase of the Term Notes (the “Buy Out
Amount”), (i) the Lenders shall assign to Biovest or its designee: (a) the Term
Notes, and (b) the Term Loan & Security Agreement and all collateral securing
the Term Notes, (ii) each of Laurus, VOF and VUS (Laurus, VOF and VUS,
collectively, the “LV Group”) shall assign an aggregate of 9,232,132 shares of
common stock of Biovest owned by the LV Group as of the repayment date (the “LV
Subject Common Stock”), (iii) PSD shall assign 1,000,000 shares of common stock
of Biovest owned by PSD as of the repayment date (the “PSD Subject Common
Stock”) and (iv) one half of each of the Lenders ownership interest of the
BiovaxID Biologic Products Royalty representing in the aggregate a 3.125%
Royalty (the “Subject Royalty”). For clarity the Lenders will retain in the
aggregate a 3.125% Royalty and Biovest will acquire a 3.125% Royalty.

 

  B. Prior to August 15, 2012, the Lenders may only sell their shares of Biovest
common stock in SEC Rule 144 market transactions, provided, that, the maximum
number of shares that may be sold is limited to 1% of the outstanding shares of
Biovest or an aggregate of 1,454,881 shares (the “Lender Excluded Shares”).
Subject to Clause D below, the above restriction in this Clause B shall not
apply after August 15, 2012.

 

  C.

If on or before August 15, 2012, Biovest fails to pay to LV the entire Buy Out
Amount but Biovest does indefeasibly pay at least $20 million in cash to LV in
partial repayment of the outstanding principal balance of the Term Notes (such
qualifying partial repayment, the “Minimum Paydown Amount”): (i) LV and the
Lenders will agree to amend together with Biovest the Term Notes such that:
(a) the maturity date of the Term Notes will be extended to December 31, 2014;
(b) the section providing a right to mandatory prepayment of the Term Notes
(Section 4.4) may be deleted or otherwise modified by Biovest; (c) the
provisions of Section 2.2 regarding the right to be granted a certain number of
seats on the Biovest Board upon certain events of default may be deleted or
otherwise modified by Biovest and (ii) to the extent that the proceeds of the
Minimum Paydown Amount are derived from funds borrowed by Biovest from a third
party lender (the “New Lender”) then, in such case: (a) Biovest may issue a note
to such New Lender with a principal balance equal to the aggregate amount of
such borrowed money not to exceed the amount of the actual Minimum Paydown
Amount paid to LV plus an additional $12 million maturing no earlier than
December 31, 2014, (b) Biovest may also grant to such New Lender a security
interest in the same of Biovest’s assets which

 

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  currently collateralize the Term Notes held by the Lenders and such new liens
granted by Biovest for the benefit of the New Lender shall be deemed Permitted
Liens under the Term Loan & Security Agreement and the Ancillary Agreements, and
(c) upon request LV, on behalf of the Lenders, shall negotiate and enter into
with Biovest and such New Lender a pari passu inter-creditor agreement in form
and substance mutually acceptable to each of LV, the Lenders, Biovest and such
New Lender such that the lien and payment priority of LV and the Lenders and
such New Lender shall be pari passu; provided, that, no intervening security
interests shall be permitted to exist between those of LV, the Lenders and such
New Lender at the time of negotiating such pari passu inter-creditor agreement;
(iii) the LV Group will assign and transfer to Biovest or its designee(s) the
percentage of the LV Subject Common Stock equal to the amount of the Minimum
Paydown Amount actually paid to LV divided by $30.9 million (For example: a
repayment of $20 million would result in 65% of the LV Subject Common Stock (or
6,000,886 shares of the LV Subject Common Stock being transferred to Biovest and
3,231,246 shares of the LV Subject Common Stock being retained by the LV Group)
and as a second example a repayment of $25 million would result in 81% of the LV
Subject Common Stock (or 7,478,027 shares of the LV Subject Common Stock being
transferred to Biovest and 1,754,105 shares of the LV Subject Common Stock being
retained by the LV Group)); (iv) the PSD will assign and transfer to Biovest or
its designee(s) the percentage of the PSD Subject Common Stock equal to the
amount of the Minimum Paydown Amount actually paid to LV divided by $30.9
million (For example: a repayment of $20 million would result in 65% of the PSD
Subject Common Stock (or 650,000 shares of the PSD Subject Common Stock being
transferred to Biovest and 350,000 shares of the PSD Subject Common Stock being
retained by PSD) and as a second example a repayment of $25 million would result
in 81% of the PSD Subject Common Stock (or 810,000 shares of the PSD Subject
Common Stock being transferred to Biovest and 190,000 shares of the PSD Subject
Common Stock being retained by PSD)); (v) the Lenders will assign and transfer
to Biovest or its designee(s) the percentage of the Subject Royalty equal to the
amount of the Minimum Paydown Amount actually paid in cash to LV divided by
$30.9 million and then multiplied by  1/2 (For example: a repayment of $20
million would result in 32% of the Subject Royalty being returned to Biovest and
68% of the Subject Royalty being retained by the Lenders (or 2.03% of the 6.25%
Subject Royalty being returned to Biovest and 4.22% of the 6.25% Subject Royalty
being retained by the Lenders) and as a second example a repayment of $25
million would result in 40% of the Subject Royalty being returned to Biovest and
60% of the Subject Royalty being retained by the Lenders (or 2.53% of the 6.25%
Subject Royalty being transferred to Biovest and 3.72% of the 6.25% Subject
Royalty being retained by the Lenders) and (vi) if Biovest indefeasibly repays
all of the remaining principal and

 

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  interest under the Term Notes within 90 days following the repayment of at
least $20 million, the Lenders will transfer and assign to Biovest: (i) the Term
Notes and all related documentation thereto, (ii) additional royalty so that
immediately following the transfer the Lenders will own in the aggregate
one-half (or 3.125%) of the 6.25% Subject Royalty and Biovest will own one-half
(or 3.125%) of the 6.25% Subject Royalty and (ii) additional shares of Biovest
common stock so that immediately following the transfer all of the LV Subject
Common Stock (representing 9,232,132 shares) and all of the PSD Subject Common
Stock (representing 1,000,000 shares) will have been transferred to Biovest.
During such 90 day period following the payment of the Minimum Paydown Amount on
or prior to August 15, 2012, the Lenders will not sell any of the LV Subject
Common Stock retained by the Lenders and PSD will not sell any of the PSD
Subject Common Stock retained by PSD.

 

  D. If on or before August 15, 2012, Biovest has an executed binding and
enforceable commitment from a third party, subject to customary due diligence,
document preparation and other closing conditions for syndicated loans from U.S.
chartered banking institutions, to fund the Minimum Paydown Amount or purchase
of the Term Notes in their entirety, LV and the Lenders will grant a 45 day
extension to permit time for Biovest to close the transaction provided Biovest
pays the interest accruing under the Term Notes on a monthly basis during the
additional extension period.

 

  E. With respect to 3,000,000 shares of the total number of Biovest common
stock held as of the date hereof by PSD (the “PSD Restricted Shares”), to the
extent that LV has received by or on behalf of PSource after the date hereof and
on or before August 15, 2012, either the Buy Out Amount or the Minimum Paydown
Amount, (i) PSD hereby agrees to enter into an Option and Lock Up Agreement in
the form attached hereto as Exhibit A (the “Lock-Up Agreement”) whereby, subject
to the terms and conditions of such Lock-Up Agreement, the sale and/or
assignment of the PSD Restricted Shares would be prohibited for a period of two
years from the date hereof (the “Lock-Up Period”), and (ii) during such Lock-Up
Period, Biovest or its designee shall have the option to purchase all or any
portion of the PSD Restricted Shares for a purchase price of $0.50 per share in
cash.

 

2. MISCELLANEOUS.

 

  A. Biovest hereby represents and warrants to LV and the Lenders the following
as a material inducement to LV and the Lenders to enter into this Letter
Agreement:

(i) Biovest has all requisite power and authority and full legal capacity to
execute and deliver this Letter Agreement and to perform its obligations
hereunder;

 

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(ii) Biovest is duly organized, validly existing and in good standing under the
laws of the state of Delaware;

(iii) all of Biovest’s representations and warranties set forth in the Term
Notes, the Term Loan & Security Agreement and each other Ancillary Agreement are
true and correct as of the date hereof (or when given if expressly limited to a
specific date), all covenant requirements set forth therein have been met and
there current does not exist any default or event of default under such
documents and/or instruments;

(iv) The execution, delivery and performance of this Letter Agreement by the
undersigned on behalf of Biovest and the consummation of the transactions
contemplated hereby by Biovest have been duly and validly authorized by all
requisite action on the part of Biovest, and no other proceedings on Biovest’s
part are necessary to authorize the execution, delivery or performance of this
Letter Agreement; and

(v) The execution, delivery and performance of this Letter Agreement by Biovest
and the consummation of the transactions contemplated hereby do not conflict
with or result in any material breach of, constitute a material default under,
result in a material violation of, result in the creation of any material lien,
security interest, charge or encumbrance upon any material assets of Biovest
(except as may be expressly contemplated herein), or require any material
authorization, consent, approval, exemption or other material action by or
notice to any court, other governmental body or other third party, under the
provisions of any material indenture, mortgage, lease, loan agreement or other
material agreement or instrument to which Biovest is bound, or any law, statute,
rule or regulation or order, judgment or decree to which Biovest is subject.

 

  B. To the extent that each of the representations and warranties of Biovest
set forth above are true and correct as of the date hereof, this Letter
Agreement shall first become effective as of the first date upon which (i) each
of LV, the Lenders and Biovest shall have duly executed and exchanged their
respective counterpart signatures to this Letter Agreement, (ii) Accentia
Biopharmacueticals, Inc. (“ABPI”) shall deliver to LV a duly authorized and
executed reaffirmation and ratification agreement in form and substance
satisfactory to LV which agreement shall reaffirm and ratify all of ABPI’s
agreements and grants of security to LV in relation to the obligations arising
under the Term Notes as amended hereby and (iii) Corps Real LLC (or their
assign), as senior lender to Biovest, shall consent to and acknowledge this
Letter Agreement and further agree to waive all claims against LV and the
Lenders to collect from LV and/or any Lender any proceeds received by LV and/or
the Lenders resulting from the purchase/assignment or repayment of the Term
Notes as contemplated herein, such payments to LV and/or the Lenders to be
expressly permitted under the terms of that certain Subordination Agreement,
dated as of November 17, 2010 by and between LV, Corps Real LLC and Biovest, as
amended and restated from time to time.

 

  C.

Except as specifically amended herein, there are no other amendments,
modifications or waivers to the Term Notes, the Term Loan & Security Agreement
or any other Ancillary Agreement, and all of the other forms, terms and
provisions of the Term Notes, the Term Loan & Security Agreement and each other
Ancillary Agreement shall remain in full

 

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  force and effect, and are hereby ratified and confirmed. The execution,
delivery and effectiveness of this Letter Agreement shall not operate as a
waiver of any right, power or remedy, nor constitute a waiver of any provision
of the Term Notes, the Term Loan & Security Agreement or any Ancillary Agreement
except as otherwise provided herein. This Letter Agreement shall be binding upon
and inure to the benefit of the parties hereto and their respective heirs,
executors, administrators, successors and assigns and shall be governed by and
construed in accordance with the laws of the State of New York.

 

  D. If Biovest fails to purchase the Term Notes from the Lenders in their
entirety or repay to LV the Minimum Paydown Amount on or before August 15, 2012
(or, subject to satisfaction of the conditions set forth in Clause 1.D. above,
within 45 days following August 15, 2012), this Letter Agreement shall
automatically terminate and be of no continuing effect.

 

  E. This Letter Agreement may be executed by the parties hereto in one or more
counterparts, each of which shall be deemed an original and all of which when
taken together shall constitute one and the same agreement. Any signature
delivered by a party by facsimile or ‘pdf’ or other electronic transmission
shall be deemed to be an original signature hereto.

[Remainder of Page Intentionally Left Blank]

 

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IN WITNESS WHEREOF, the parties hereto have executed this Letter Agreement as of
the date first set forth above.

 

Very truly yours, LV ADMINISTRATIVE SERVICES, INC., as administrative/collateral
agent for the Lenders By:  

/s/ Eugene Grin

Name:   Eugene Grin Title:   Authorized Signatory BIOVEST INTERNATIONAL, INC.
By:  

/s/ Samuel S. Duffey

Name:   Samuel S. Duffey Title:   CEO and President

 

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ACKNOWLEDGED AND AGREED: LAURUS MASTER FUND, LTD. (IN LIQUIDATION) By:  

/s/ Russell Smith

Name:   Russell Smith Title:   Authorized Signatory ERATO CORPORATION, by Laurus
Capital Management, LLC, its investment manager By:  

/s/ Eugene Grin

Name:   Eugene Grin Title:   Authorized Signatory VALENS OFFSHORE SPV I, LTD.,
by Valens Capital Management, LLC, its investment manager By:  

/s/ Eugene Grin

Name:   Eugene Grin Title:   Authorized Signatory VALENS OFFSHORE SPV II, CORP.,
by Valens Capital Management, LLC, its investment manager By:  

/s/ Eugene Grin

Name:   Eugene Grin Title:   Authorized Signatory VALENS U.S. SPV I, LLC., by
Valens Capital Management, LLC, its investment manager By:  

/s/ Eugene Grin

Name:   Eugene Grin Title:   Authorized Signatory PSOURCE STRUCTURED DEBT
LIMITED, by PSource Capital Limited, its investment consultant By:  

/s/ Soondra Apparoo

Name:   Soondra Apparoo Title:   Managing Director

 

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EXHIBIT A

FORM OF OPTION AND LOCK-UP AGREEMENT

 

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PSOURCE STRUCTURED DEBT LIMITED

SARNIA HOUSE, LE TRUCHOT

ST PETER PORT. GUERNSEY, GY1 4NA

                 , 201    

Biovest International, Inc.

324 South Hyde Park Avenue, Suite 350

Tampa, Florida 33606

Attn: Chief Executive Officer/President

 

  Re: Biovest International, Inc. (the “Company”)

Gentlemen:

PSource Structured Debt Limited (“PSD”) is an owner of record or beneficially of
certain shares of common stock (“Common Stock”) of the Company. The Company
proposes to enter into an amendment to: (i) the Term Loan & Security Agreement
dated as of November 17, 2010 (as amended, supplemented, restated or modified
from time to time, the “Term Loan & Security Agreement”) by and between LV
Administrative Services, Inc. (“LV”) as Agent for and on behalf of each of
Laurus Master Fund, Ltd. (in liquidation) (“Laurus”), Erato Corporation
(“Erato”), Valens Offshore SPV I, Ltd. (“VOF”), Valens Offshore SPV II, Corp.
(“VOF2”), Valens U.S. SPV I, LLC. (“VUS”), PSource Structured Debt Limited
(“PSD”) and the other creditor parties named therein from time to time (Laurus,
Erato, VOF, VOF2, VUS, PSD and such other creditor parties, collectively, the
“Lenders”); (ii) Secured Term Notes A and B (the “Term Notes”) issued on or
about November 17, 2010 to the Lenders by the Company; and (iii) the Ancillary
Agreements (as defined in the Term Loan & Security Agreement) (the
“Transaction”). PSD recognizes that the Transaction will be of benefit to PSD
and will benefit the Company. PSD acknowledges that the Company is relying on
the representations and agreements of PSD contained in this letter agreement in
carrying out the Transaction.

In consideration of the foregoing and solely in respect of 3,000,000 shares of
Common Stock currently owned either of record or beneficially by PSD (the
“Restricted Common Stock”), PSD hereby agrees that it will not, without the
prior written consent of the Company, directly or indirectly, sell, offer,
contract or grant any option to sell (including without limitation any short
sale), pledge, transfer, establish an open “put equivalent position” within the
meaning of Rule 16a-1(h) under the Securities Exchange Act of 1934, as amended,
or otherwise dispose of any shares (collectively, a “Transfer”) of the
Restricted Common Stock currently owned either of record or beneficially (as
defined in Rule 13d-3 under the Securities Exchange Act of 1934, as amended) by
PSD, or publicly announce an intention to do any of the foregoing, during the
period (the “Restricted Period”) commencing on the date hereof and ending on
May     , 2014, subject to the exclusions and termination events otherwise
described in this letter agreement. The restrictions as set forth in the
immediately preceding sentence shall not apply to: (1) during the Restricted
Period the Transfer of any or all of the shares of Restricted Common Stock owned
by PSD to any affiliate of PSD, liquidating trust (or another similarly purposed
structure) the beneficiaries of which are PSD’s shareholders and/or investors or
any other party in a private sale transaction; provided, however,

 

     

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that it shall be a condition to such Transfer that the transferee executes and
delivers to the Company an agreement stating that the transferee is receiving
and holding the Restricted Common Stock subject to the provisions of this letter
agreement, and there shall be no further transfer of such Restricted Common
Stock except in accordance with this letter agreement; and (ii) during the
period commencing on the twelve (12) month anniversary of the date hereof
through the expiration of the Restricted Period, the Transfer of any or all of
the shares of Restricted Common Stock owned by PSD to any other party; provided,
that, PSD shall obtain the prior written consent from the Company for each such
proposed Transfer (which consent shall not be unreasonably withheld by the
Company); provided, further, that, to the extent that the Company does not
respond to a request for consent from PSD within 5 business days of delivery
thereof, consent to such proposed Transfer shall be deemed granted by the
Company. Furthermore, to the extent and in the manner as described in clauses
(i) through (iii) below, the Transfer restrictions set forth above in this
letter agreement shall be automatically terminated and of no further force or
effect (each, a “Release”):

(i) on the 90th day immediately following the date hereof (the “Partial Release
Date”), a Release shall occur in respect of that number of shares of the
Restricted Common Stock determined by using the following formula (the “90th Day
Released Shares”):

X = 3,000,000 – (3,000,000 x (Y/$30,900,000))

X =    Number of shares of Restricted Common Stock to be released

Y =    The aggregate amount of all repayments made by or on behalf of the
Company of the outstanding principal balance of the Term Notes and received by
LV between May     , 2012 and the Partial Release Date.

For example: a repayment of an aggregate amount of $20 million by the Partial
Release Date would result in the release of approximately 35% of the Restricted
Common Stock (or 1,058,253 shares of the Restricted Common Stock) from the
Transfer restrictions set forth in this letter agreement and as a second example
a repayment of $25 million would result in the release of approximately 19% of
the Restricted Common Stock (or 572,816 shares of the Restricted Common Stock)
from the Transfer restrictions set forth in this letter agreement.

; and

(ii) if a Trigger Event shall have occurred then, in such case, on the later to
occur of the Partial Release Date and the date of expiration of the Purchase
Option Exercise Period (as defined below), a Release shall also occur in respect
of those shares of Restricted Common Stock available for purchase by the Company
from PSD pursuant to the terms of this letter agreement that are not subject to
a timely executed and delivered Purchase Option Notice (as defined below)
hereunder (the “Additional Released Shares”); and

(iii) if a Trigger Event shall have occurred and a Purchase Option Notice
delivered in accordance with the terms and conditions of this Agreement, on the
date of expiration of the Closing Period (as defined below) a Release shall
occur in respect of all remaining shares of Restricted Common Stock not
otherwise previously Released hereunder, and, at the sole option of PSD, all
agreements related to a proposed Closing shall be automatically terminated and
have no further force or effect.

PSD also agrees and consents to the entry of stop transfer instructions with the
Company’s transfer agent and registrar against the transfer of shares of the
Restricted Common Stock held by PSD except in compliance with the foregoing
restrictions (subject to all exclusions and termination events as also described
in this letter agreement).

 

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In the event that at any time during the Restricted Period, the average closing
price of the Common Stock (as reported by Bloomberg, L.P.) for twenty
(20) consecutive trading days is greater than or equal to $1.25 per share at the
end of each such day (the “Trigger Event” and, the last day of such Trigger
Event, the “Trigger Date”), PSD hereby grants to the Company, subject to the
terms and conditions herein described, the right to purchase (the “Purchase
Option”) from PSD for a cash purchase price of $0.50 per share in a single
transaction up to that number of shares of Restricted Common Stock as determined
using the following formula (the “Maximum Available Share Formula”):

X = 3,000,000 x (Y/$30,900,000)

X =     Number of shares of Restricted Common Stock available for purchased by
the Company upon occurrence of Trigger Date.

Y =     The aggregate amount of all repayments of the outstanding principal
balance of the Term Notes made by or on behalf of the Company (and received by
LV) between May     , 2012 and the Partial Release Date.

For example: the occurrence of a Trigger Event and an aggregate repayment of $20
million by the Partial Release Date would result in a Purchase Option right for
up to approximately 65% of the Restricted Common Stock (or 1,941,747 shares of
the Restricted Common Stock) and as a second example, the occurrence of a
Trigger Event and an aggregate repayment of $25 million would result in a
Purchase Option right for up to approximately 81% of the Restricted Common Stock
(or 2,427,184 shares of the Restricted Common Stock).

In the event that the Company wishes to exercise the Purchase Option, the
Company shall deliver no later than the twentieth (20th) day following delivery
of notice from PSD of the occurrence of the Trigger Event (the “Purchase Option
Exercise Period”), a notice (the “Purchase Option Notice”) to the offices of PSD
c/o                                         or such other location designated in
writing by PSD (with a copy to LV at                                         or
such other location designated in writing by LV) setting forth (i) the proposed
date of such exercise, and (ii) subject to the restriction imposed by the
Maximum Available Share Formula, the number of shares of Restricted Common Stock
subject to such exercise of the Purchase Option. In the event that a Trigger
Event occurs prior to the Partial Release Date, to the extent that the Company
repays additional principal indebtedness under the Term Notes after expiration
of the Purchase Option Exercise Period and prior to the Partial Release Date, on
the Partial Release Date the Company may revise upon written notice to PSD that
number of shares of Restricted Common Stock subject to such Purchase Option
exercise by recalculating the Maximum Available Share Formula incorporating such
additional repaid principal indebtedness. The closing for the exercise of the
Purchase Option (the “Closing”) shall take place, and all cash payments from the
Company to PSD shall be delivered to LV, no later than one hundred (100) days
following first receipt of a Purchase Option Notice (the “Closing Period”) at
the offices of the PSD, or such other location designated in writing by PSD. At
the Closing, PSD shall deliver the applicable shares of Restricted Common Stock
related to such Closing, deeds, assignments and other instruments of sale,
assignment and transfer of the Restricted Common Stock related to such Closing
(including, without limitation, evidence of due authorization, execution and

 

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delivery of the instruments of transfer, evidence of title and the absence of
any liens or competing claims) as the Company shall reasonably request to
effectively transfer good and valid title to the Restricted Common Stock related
to such Closing. The Company shall pay any registration fees or other similar
stamp or other taxes or fees payable or due upon the exercise of the Purchase
Option and any such sale, assignment and/or transfer related thereto. The
Company hereby acknowledges that PSD beneficial owns or is owner of record of
shares of Common Stock in addition to the Restricted Common Stock (the
“Non-Restricted Common Stock”) and further agrees that the restrictions set
forth in this letter agreement do not apply to the Non-Restricted Common Stock
(though other restrictions may from time to time apply under law or contract).

This Letter Agreement shall be binding upon and inure to the benefit of the
parties hereto and their respective heirs, executors, administrators, successors
and assigns and shall be governed by and construed in accordance with the laws
of the State of New York.

This Letter Agreement may be executed by the parties hereto in one or more
counterparts, each of which shall be deemed an original and all of which when
taken together shall constitute one and the same agreement. Any signature
delivered by a party by facsimile or ‘pdf’ or other electronic transmission
shall be deemed to be an original signature hereto.

[Remainder of Page Intentionally Left Blank]

 

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IN WITNESS WHEREOF, the parties hereto have executed this Letter Agreement as of
the date first set forth above.

 

PSOURCE STRUCTURED DEBT LIMITED

By: PSource Capital Limited, its investment consultant

By:  

 

Name:   Title:   AGREED AND ACKNOWLEDGED: BIOVEST INTERNATIONAL, INC. By:  

 

Name:   Title:  

 

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