Exhibit 10.44

SIXTH AMENDMENT AND FORBEARANCE
TO
LOAN AND SECURITY AGREEMENT

THIS SIXTH AMENDMENT AND FORBEARANCE to Loan and Security Agreement
(this “Amendment and Forbearance”) is entered into on October 29, 2007, by and
between
 
SILICON VALLEY BANK (“Bank”)
 
and the following (collectively, jointly and severally, the "Borrower") whose
address is 20200 Sunburst Street, Chatsworth, California 91311:
 
NORTH AMERICAN SCIENTIFIC, INC., a Delaware corporation (“NASI”); and
 
NORTH AMERICAN SCIENTIFIC, INC., a California corporation (“NASI-CA”).

 
Recitals
 
A. Bank and Borrower have entered into that certain Loan and Security Agreement,
with an Effective Date of October 5, 2005 (as the same has been, and may
hereafter from time to time be amended, modified, supplemented or restated, the
“Loan Agreement”).
 
B. Bank has extended credit to Borrower for the purposes permitted in the Loan
Agreement.
 
C. Borrower is currently in default of the Loan Agreement for failing to comply
with the Minimum Tangible Net Worth Financial Covenant set forth in Section 5 of
the Amended and Restated Schedule 2 to Loan and Security Agreement for each of
the months ending July 31, 2007, August 31, 2007 and September 30, 2007 (the
“Existing Defaults”).
 
D. Borrower has requested that Bank forbear from exercising its rights and
remedies against Borrower from the date hereof until such time as Bank
determines in its discretion to cease such forbearance (the “Forbearance
Period”). Although Bank is under no obligation to do so, Bank is willing to
forbear from exercising its rights and remedies against Borrower through the
Forbearance Period on the terms and conditions set forth in this Amendment and
Forbearance, so long as Borrower complies with the terms, covenants and
conditions set forth in this Amendment and Forbearance in a timely manner.
Moreover, the parties desire to amend the Loan Agreement as herein set forth.
 
 

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Agreement
 
Now, Therefore, in consideration of the foregoing recitals and other good and
valuable consideration, the receipt and adequacy of which are hereby
acknowledged, and intending to be legally bound, the parties hereto agree as
follows:
 
1. Definitions. Capitalized terms used but not defined in this Amendment and
Forbearance shall have the meanings given to them in the Loan Agreement.
 
2. Amendments and Forbearance to Loan Agreement. The Loan Agreement is hereby
amended as follows, effective as of the date hereof:
 
2.1 Forbearance Period. So long as no Event of Default, other than the Existing
Defaults, occurs, subject to the terms and conditions set forth herein, Bank
shall forbear from filing any legal action or instituting or enforcing any
rights and remedies it may have against Borrower through the Forbearance Period.
Except as expressly provided herein, this Amendment and Forbearance does not
constitute a waiver or release by Bank of any Obligations or of any existing
Event of Default or of any Event of Default which may arise in the future after
the date of execution of this Amendment and Forbearance. If Borrower does not
comply with the terms of this Amendment and Forbearance, Bank shall have no
further obligations under this Amendment and Forbearance and shall be permitted
to exercise at such time any rights and remedies against Borrower as it deems
appropriate in its sole and absolute discretion. Borrower understands that Bank
has made no commitment and is under no obligation whatsoever to grant any
additional extensions of time at the end of the Forbearance Period.
 
2.2 Forbearance Terms. Repayment and performance of all Obligations of Borrower
to Bank under the Loan Agreement and this Amendment and Forbearance shall be
secured by the Collateral.
 
2.3 Modified Maturity Date. The Maturity Date set forth in Section 4 of the
Amended and Restated Schedule 2 to Loan and Security Agreement is hereby amended
to read as follows:
 
4. MATURITY DATE 

(Section 13.1):
November 20, 2007.

 
Notwithstanding the foregoing, the Maturity Date with respect to the Bridge Loan
Sublimit shall be the earlier of (i) November 20, 2007 or (ii) the date Borrower
closes the private investment public equity transaction of which Silicon has
been advised by Borrower (which Borrower has informed Silicon would result in
the receipt of more than $15,000,000 net cash proceeds to Borrower) (the
“PIPE”).

 
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2.4 Consent to Friede Subordinated Debt. Notwithstanding anything to the
contrary in the Loan Agreement, Bank hereby consents to the Borrower issuing up
to $500,000 in subordinated debt to Mr. John Friede (or an entity owned or
controlled by Mr. Friede) (“Friede”), which debt shall be unsecured, provided
that Friede execute and deliver to Bank, on Bank’s standard form with such
changes thereto as are acceptable to Bank in its good faith business judgment, a
subordination agreement pursuant to which the debt owed by Borrower to Friede
will be fully subordinated to the Obligations.
 
3. Limitation of Amendments and Forbearance.
 
3.1 The amendments and forbearance set forth in Section 2, above, are effective
for the purposes set forth herein and shall be limited precisely as written and
shall not be deemed to (a) be a consent to any amendment, waiver or modification
of any other term or condition of any Loan Document, or (b) otherwise prejudice
any right or remedy which Bank may now have or may have in the future under or
in connection with any Loan Document.
 
3.2 This Amendment and Forbearance shall be construed in connection with and as
part of the Loan Documents and all terms, conditions, representations,
warranties, covenants and agreements set forth in the Loan Documents, except as
herein amended, are hereby ratified and confirmed and shall remain in full force
and effect.
 
4. Representations and Warranties. To induce Bank to enter into this Amendment
and Forbearance, Borrower hereby represents and warrants to Bank as follows:
 
4.1 Immediately after giving effect to this Amendment and Forbearance (a) the
representations and warranties contained in the Loan Documents are true,
accurate and complete in all material respects as of the date hereof (except to
the extent such representations and warranties relate to an earlier date, in
which case they are true and correct as of such date), and (b) no Event of
Default has occurred and is continuing (other than the Existing Defaults);
 
4.2 Borrower has the corporate power and authority to execute and deliver this
Amendment and Forbearance and to perform its obligations under the Loan
Agreement, as amended by this Amendment and Forbearance;
 
4.3 The organizational documents of Borrower delivered to Bank on the Effective
Date remain accurate and complete and have not been amended, supplemented or
restated since the Effective Date and are, and continue to be, in full force and
effect;
 
4.4 The execution and delivery by Borrower of this Amendment and Forbearance and
the performance by Borrower of its obligations under the Loan Agreement, as
amended by this Amendment and Forbearance, have been duly authorized;
 
4.5 The execution and delivery by Borrower of this Amendment and Forbearance and
the performance by Borrower of its obligations under the Loan Agreement, as
amended by this Amendment and Forbearance, do not and will not contravene
(a) any law or regulation binding on or affecting Borrower, (b) any material
agreement by which Borrower or its property is bound, (c) any order, judgment or
decree of any court or other governmental or public body or authority, or
subdivision thereof, binding on Borrower, or (d) the organizational documents of
Borrower;
 
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4.6 The execution and delivery by Borrower of this Amendment and Forbearance and
the performance by Borrower of its obligations under the Loan Agreement, as
amended by this Amendment and Forbearance, do not require any order, consent,
approval, license, authorization or validation of, or filing, recording or
registration with, or exemption by any governmental or public body or authority,
or subdivision thereof, binding on either Borrower, except as already has been
obtained or made; and
 
4.7 This Amendment and Forbearance has been duly executed and delivered by
Borrower and is the binding obligation of Borrower, enforceable against Borrower
in accordance with its terms, except as such enforceability may be limited by
bankruptcy, insolvency, reorganization, liquidation, moratorium or other similar
laws of general application and equitable principles relating to or affecting
creditors’ rights.
 
5. Prior Agreement. The Loan Documents are hereby ratified and reaffirmed and
shall remain in full force and effect. This Amendment and Forbearance is not a
novation and the terms and conditions of this Amendment and Forbearance shall be
in addition to and supplemental to all terms and conditions set forth in the
Loan Documents. In the event of any conflict or inconsistency between this
Amendment and Forbearance and the terms of such documents, the terms of this
Amendment and Forbearance shall be controlling, but such document shall not
otherwise be affected or the rights therein impaired.
 
6. Release by Borrower.
 
6.1 FOR GOOD AND VALUABLE CONSIDERATION, Borrower hereby forever relieves,
releases, and discharges Bank and its present or former employees, officers,
directors, agents, representatives, attorneys, and each of them, from any and
all claims, debts, liabilities, demands, obligations, promises, acts,
agreements, costs and expenses, actions and causes of action, of every type,
kind, nature, description or character whatsoever, whether known or unknown,
suspected or unsuspected, absolute or contingent, arising out of or in any
manner whatsoever connected with or related to facts, circumstances, issues,
controversies or claims existing or arising from the beginning of time through
and including the date of execution of this Amendment and Forbearance
(collectively “Released Claims”). Without limiting the foregoing, the Released
Claims shall include any and all liabilities or claims arising out of or in any
manner whatsoever connected with or related to the Loan Documents, the Recitals
hereto, any instruments, agreements or documents executed in connection with any
of the foregoing or the origination, negotiation, administration, servicing
and/or enforcement of any of the foregoing.
 
6.2 In furtherance of this release, Borrower expressly acknowledges and waives
any and all rights under Section 1542 of the California Civil Code, which
provides as follows:
 
“A general release does not extend to claims which the creditor does not know or
expect to exist in his favor at the time of executing the release, which if
known by him must have materially affected his settlement with the debtor.”
(Emphasis added.)
 
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6.3 By entering into this release, Borrower recognizes that no facts or
representations are ever absolutely certain and it may hereafter discover facts
in addition to or different from those which it presently knows or believes to
be true, but that it is the intention of Borrower hereby to fully, finally and
forever settle and release all matters, disputes and differences, known or
unknown, suspected or unsuspected; accordingly, if Borrower should subsequently
discover that any fact that it relied upon in entering into this release was
untrue, or that any understanding of the facts was incorrect, Borrower shall not
be entitled to set aside this release by reason thereof, regardless of any claim
of mistake of fact or law or any other circumstances whatsoever. Borrower
acknowledges that it is not relying upon and has not relied upon any
representation or statement made by Bank with respect to the facts underlying
this release or with regard to any of such party’s rights or asserted rights.
 
6.4 This release may be pleaded as a full and complete defense and/or as a
cross-complaint or counterclaim against any action, suit, or other proceeding
that may be instituted, prosecuted or attempted in breach of this release.
Borrower acknowledges that the release contained herein constitutes a material
inducement to Bank to enter into this Amendment and Forbearance, and that Bank
would not have done so but for Bank’s expectation that such release is valid and
enforceable in all events.
 
6.5 Borrower hereby represents and warrants to Bank, and Bank is relying
thereon, as follows:
 
(a) Except as expressly stated in this Amendment and Forbearance, neither Bank
nor any agent, employee or representative of Bank has made any statement or
representation to Borrower regarding any fact relied upon by Borrower in
entering into this Amendment and Forbearance.
 
(b) Borrower has made such investigation of the facts pertaining to this
Amendment and Forbearance and all of the matters appertaining thereto, as it
deems necessary.
 
(c) The terms of this Amendment and Forbearance are contractual and not a mere
recital.
 
(d) This Amendment and Forbearance has been carefully read by Borrower, the
contents hereof are known and understood by Borrower, and this Amendment and
Forbearance is signed freely, and without duress, by Borrower.
 
(e) Borrower represents and warrants that it is the sole and lawful owner of all
right, title and interest in and to every claim and every other matter which it
releases herein, and that it has not heretofore assigned or transferred, or
purported to assign or transfer, to any person, firm or entity any claims or
other matters herein released. Borrower shall indemnify Bank, defend and hold it
harmless from and against all claims based upon or arising in connection with
prior assignments or purported assignments or transfers of any claims or matters
released herein.
 
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7. Counterparts. This Amendment and Forbearance may be executed in any number of
counterparts and all of such counterparts taken together shall be deemed to
constitute one and the same instrument.
 
8. Effectiveness. This Amendment and Forbearance shall be deemed effective upon
(a) the due execution and delivery to Bank of this Amendment and Forbearance by
each party hereto and (b) Borrower’s payment of an extension fee (with respect
to the Revolving Line Credit Amount) in an amount equal to $450.
 
9. Covenant Regarding Payment of Fee for Extension of Bridge Loan Sublimit and
Continued Forbearance. In consideration for Bank extending the Maturity Date of
the Bridge Loan Sublimit and for Bank continuing to forbear from exercising its
right and remedies as set forth herein, Borrower covenants and agrees that it
shall pay to Bank an extension fee in an amount equal to $250 per day from
November 9, 2007 until (and such amount shall be payable on) the earlier of (i)
November 20, 2007 or (ii) the date Borrower closes the PIPE. The foregoing is in
addition to the $250 per day fee Borrower has agreed to pay Bank pursuant to
that certain Fifth Amendment and Forbearance to Loan and Security Agreement.
 
10. Governing Law. This Amendment and Forbearance and the rights and obligations
of the parties hereto shall be governed by and construed in accordance with the
laws of the State of California.
 
[Signature page follows.]

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In Witness Whereof, the parties hereto have caused this Amendment and
Forbearance to be duly executed and delivered as of the date first written
above.

“Borrower”:
 
“Bank”:
       
NORTH AMERICAN
SCIENTIFIC, INC.
 
SILICON VALLEY BANK
A Delaware corporation
               
By
/s/James W. Klingler
 
By
/s/Derek Brunelle
 
President or Vice President
 
Title
Vice President
         
“Borrower”:
             
NORTH AMERICAN
SCIENTIFIC, INC. 
     
A California corporation
             
By
/s/James W. Klingler
       
President or Vice President
     

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