Amendment of the Agreement on the Establishment of a Snake Farm and Purification Unit

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

(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.

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.

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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).

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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

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

Exhibit B

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€

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 1^st, 2006 beginning of validation and GMP approval until December 31^st, 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.

Direct costs:

Indirect costs:

Nordmark services:

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