Exhibit 10.28

Amendment

of the

Agreement on the Establishment

of a Snake Farm and Purification Unit

The following new version of the article 6 replaces article 6 from 6.1 to 6.7 of
the

agreement signed January 18, 2006

Article 6

Financial Obligations of the Parties

 

6.1 As of the Effective Date, the costs for Part I of the Project are estimated
at EURO 4,500,000.00 (in words: EURO Four Million Five Hundred Thousand), and
for Part II of the Project at EURO 1,500,000.00 (in words: EURO One Million Five
Hundred Thousand), totaling EURO 6,000,000.00 (in words: EURO Six Million) for
completion of the Ancrod Facilities.

 

6.2 NTI has made a down payment of EURO 1,000,000.00 (in words EURO One
Million). Upon completion of the snake farm at Nordmark’s facilities in full
compliance with Exhibit A, Nordmark shall deliver an invoice to NTI for an
additional payment of EURO 1,000,000.00 (in words EURO One Million). Subject to
NTI’s agreement that the snake farm has been completed in accordance with
Exhibit A, such invoice shall be payable by NTI within thirty (30) days after
receipt of such invoice. Notwithstanding anything to the contrary in this Art.
6.2 or otherwise in this Snake Agreement, if this Snake Agreement is terminated
before a total of EURO 2,000,000.00 (in words EURO Two Million) is incurred in
connection with the Ancrod Facilities, then within thirty (30) days after the
date of termination of this Snake Agreement, Nordmark shall refund to NTI the
difference between (a) and (b) below, wherein:

(a) is the amount paid by NTI prior to the termination date in accordance with
this Art. 6.2 (i.e., EURO 2,000,000.00 (in words EURO Two Million) or EURO
1,000,000.00 (in words EURO One Million) and

(b) is the actual demonstrable amount reasonably incurred in connection with the
Ancrod Facilities prior to the termination date.

For the avoidance of doubt, except in the event that NTI is required to make the
Contingent Additional Consideration Payment pursuant to Art 6.3 below, NTI shall
not be required to make any payments for the Ancrod Facilities other than the
payments set forth in this Art 6.2 (i.e., a maximum of EURO 2,000,000,00 (in
words EURO Two Million), regardless of the actual costs of completing the Ancrod
Facilities.

 

6.3 Nordmark shall assume responsibility for all costs incurred in connection
with establishment of the Ancrod Facilities that exceed the total of the down
payment amount

--------------------------------------------------------------------------------

and the additional payment amount to be paid by NTI in accordance with Art. 6.2
(i.e., EURO 2,000,000.00 (in words EURO Two Million). Notwithstanding anything
to the contrary in this Art. 6.3. The following conditions that may trigger a
“Contingent Additional Consideration Payment” are subject to further discussion
by the Parties: – if (a) NTI fails to obtain at least one Registration for a
Medicinal Product containing Ancrod before the end of calendar year 2010; or
(b) NTI expressly abandons development and/or commercialization of the Viprinex
product in the United States and Europe before the end of calendar year 2010; or
(c) after good faith negotiations, NTI and Nordmark fail to execute a separate
agreement for Nordmark’s commercial manufacture and supply of GMP-grade Ancrod
pursuant to Article 9 before the end of calendar year 2010, then NTI shall pay
to Nordmark an additional consideration payment in an amount calculated as
following:

(y) the total cost of the Ancrod Facilities (which shall be the smaller of
(i) and (ii) below, wherein:

(i) is EURO 6,000,000.00 (in words EURO Six Million), the estimated costs set
forth in Art. 6.1; and

(ii) is the actual, demonstrable cost reasonably incurred by Nordmark in
establishing the Ancrod Facilities as of the date that a condition set forth in
any of clauses (a-c) above is fulfilled; and

(z) the amount that is equal to eighty percent (80%) of the cost set forth in
(y).

The Contingent Additional Consideration Payment shall be the amount of (z) minus
EURO 2,000,000 (in words EURO two Million) (see Exhibit C for various
calculations).

If such Contingent Additional Consideration Payment becomes payable by NTI in
accordance with this Art. 6.3, it shall be paid in consideration of Nordmark’s
inability to realize the full benefits of the Ancrod Facilities. In the event
that NTI provides written notice to Nordmark that NTI has failed to obtain at
least one Registration for a Medicinal Product containing Ancrod before the end
of calendar year 2010, or that NTI is abandoning development and/or
commercialization of the Viprinex product in the United States and Europe before
the end of calendar year 2010, then Nordmark thereafter shall use its
commercially reasonable efforts to avoid incurring further costs (for example,
by cancelling commitments and/or returning materials) and to mitigate any costs
incurred in connection with the Project, the Ancrod Facilities and this Snake
Agreement. For the avoidance of doubt, NTI shall not be obligated to pay to
Nordmark a Contingent Additional Consideration Payment pursuant to this Art. 6.3
if Nordmark’s acts or omissions in connection with the Project, this Snake
Agreement or the Cooperation Agreement contributed to NTI’s failure to meet the
conditions set forth in clauses (a) or (c) above.

 

6.4 If NTI is required to pay to Nordmark a Contingent Additional Consideration
Payment pursuant to Art. 6.3, and if, during the period commencing on the date
that Nordmark

 

2

--------------------------------------------------------------------------------

receives such Contingent Additional Consideration Payment and ending on the
second anniversary of such receipt date, Nordmark sells or leases all or part of
the Ancrod Facilities, or uses all or part of the Ancrod Facilities to provide
services to a third party(ies), then Nordmark shall pay to NTI twenty-five
percent (25%) of the consideration received by Nordmark for such sale(s),
lease(s) and/or services (as applicable); provided that the maximum total
payment(s) to NTI pursuant to this Art 6.4 shall not exceed EURO 2,000,000:00
(in words EURO Two Million).

 

6.5 Until Nordmark commences commercial manufacture of GMP grade Ancrod, NTI
will reimburse Nordamrk’s “fully loaded costs connected with the operation of
the snake farm and the purification unit. The definition of the “fully loaded
costs” shall be mutually agreed by the parties within 60 days after the
Effective Date.

 

6.6 Nordmark shall invoice the fees to NTI monthly, the invoices are payable
within 30 days after receipt of the invoice.

 

6.7 Nordmark may request that, at its cost, the auditor who audits Nordmark’s
annual financial accounts, controls and confirms for NTI whether the fees
charged to NTI have been calculated in compliance with this Agreement.

 

Uetersen, July 5th, 2006    Neurobiological Technologies, Inc.    Nordmark
Arzneimittel GmbH & Co. KG

 

Paul E. Freiman

President and CEO

  

/s/ Franz J. Empl

Franz J. Empl

President and CEO

  

/s/ Manfred Kurfürst

Manfred Kurfürst PhD

Head of Business Unit

Biology

 

3

--------------------------------------------------------------------------------

EXHIBIT A

Specifications, Activities, Responsibilities, Estimated Expenses and Schedules

for Completion of Part I and Part II of the Project

--------------------------------------------------------------------------------

Exhibit A (page 1 of 3)

Technical Specifications of Snake Farm

 

Parameter

  

Spezification

Air Filter    Prefilter F6    Filter H14 Particle    max. 3.500.000 particle/m3
(³ 0,5 µm)    max. 20.000 particle/m3 (³ 5,0 µm) Temperature    min. 26º C   
max. 30º C Humidity    71% - 88% r.h. Air Changes    10 - 15 Differential
Pressure    30 Pa

--------------------------------------------------------------------------------

Exhibit A (page 2 of 3)

Project schedule and activities

Project “Building a snake farm”

CHART

--------------------------------------------------------------------------------

Exhibit A (page 3 of 3)

Estimated Expenses of Snake Farm

 

Equipment

   680 T €

Construction (Shell)

   590 T €

Construction (Interior)

   550 T €

Construction (Exterior)

   300 T €

Media

   30 T €

HVAC-System

   1.050 T €

Technical

   740 T €

Engineering

   225 T €

Power Supply

   190 T €

Authority Approvals

   15 T €

Unforeseeable

   130 T €           4.500 T €       

--------------------------------------------------------------------------------

Exhibit B

 

1. Temporary solution until the snakefarm is established, relating to article 3

The temporary solution cannot be done by Abbott GmbH & Cc. KG Ludwigshafen to
realise the possibility to keep NTI Malayen pit viper snakes until the Nordmark
snakefarm is established. Nordmark will erect for this time a special container
unit (see attachment 1).

The investment cost will be approx. 550 T€

 

•      Prefabricated containers

   450

•      Foundation

   50

•      Utilities (Electric, water)

   40

•      Others (Planning etc.)

   10         550     

Nordmark guaranties all provisions agreed in the contract regarding the housing
of the Malayen pit vipers also for this case.

The investment will be totally done on Nordmarks behalf.

From May 1st, 2006 beginning of validation and GMP approval until December 31st,
2006 NTI will pay a monthly rent fee by 45 T€. The fee is invoiced through
Nordmark monthly in advanced and payable within 10 days.

All other costs for the temporary solution are included as described in the
contract, article 6, sequence 6.5 in the “fully loaded costs” until the start of
the commercial manufacture of GMP grade Ancrod. For the definition of the fully
loaded costs see separate specification.

 

2 Definition of “fully loaded costs”:

Direct costs:

 

  •   Personnel

 

  •   Energy, water, waste water

 

  •   Validation

 

  •   Monitoring

 

  •   Maintenance

 

  •   Cleaning

 

  •   Insurance

 

  •   Material

--------------------------------------------------------------------------------

Indirect costs:

Nordmark services:

 

  •   Purchasing

 

  •   Warehousing

 

  •   Quality control

 

  •   Human resources

 

  •   Finance

 

  •   Reporting

 

  •   Management

 

  •   Depreciation

 

Uetersen, March 8th, 2006

     

Neurobiological Technologies Inc.

     

Nordmark Arzneimittel GmbH & Co. KG

/s/ Paul E. Freiman

     

/s/ Peter Tonne

Paul E. Freiman

     

Mr. Peter Tonne, Ph.D.

President & CEO 3/14/06

     

/s/ Stephen Petti

     

Mr. Stephen Petti

     

/s/ Jonathan R. Wolter

     

Jonathan R. Wolter 3/14/06

     

VP & CFO

     

 

9