Service Agreement – A Formulation development of RHB-105 in oral solid dosage form and manufacture of clinical supplies Amendment 3

Service Agreement – A

Formulation development of RHB-105 in oral solid dosage form and manufacture of clinical supplies

Amendment 3

Exhibit 4.19

THE SYMBOL “[****]” DENOTES PLACES WHERE PORTIONS OF THIS DOCUMENT HAVE BEEN OMITTED PURSUANT TO A REQUEST FOR CONFIDENTIAL TREATMENT. SUCH MATERIAL HAS BEEN FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

Amendment 3 to The service Agreement A is made and entered in April 19^th, 2012 (the “Amendment”).

1. DESCRIPTION OF THE EXTRA WORK

The Client requested that the GMP Omeprazole magnesium API and GMP Amoxicillin API and GMP Rifabutin API would be analyzed by Corealis at their reception at the Corealis] facility for full testing and not only ID testing.

a. GMP Omeprazole magnesium API analytical release testing

ITEM		Cost (USD$)
ID testing
IR-Method qualification, set-up and analysis*		0$
[****]		200$
Assay
Method qualification		2,000$
Set-up		605$
Analysis		575$
Related substances
Method qualification		2,500$
Set-up**		0$
Analysis		795$
Residual solvents
Method A: [****]
[****]		14,000$
Analysis		1,200$
Water - Xxxx Xxxxxx Titration (USP <921>)
Analysis		165$
Appearance
Analysis		85$
[****]
		Analysis	75$

Corealis	Page 1 of 5
Date: April 19th, 2012

Service Agreement – A

Formulation development of RHB-105 in oral solid dosage form and manufacture of clinical supplies

Amendment 3

[****]		Analysis	170$
[****]
Analysis		550$
Report****		688$
		_______
Sub total for section 1. a.		23,608$
b. GMP Amoxicillin trihydrate API analytical release testing
ITEM		Cost (USD$)
ID testing
IR-Method qualification, set-up and analysis*		0$
Assay
Method qualification		2,000$
Set-up		605$
Analysis		575$
Related substances
Method qualification		2,500$
Set-up**		0$
Analysis		795$
pH
Analysis		85$
Residual solvents
[****]
[****]
[****]
[****]		30,000$
[****]		1,800$
Water - Xxxx Xxxxxx Titration (USP <921>)
Analysis		165$
Appearance
Analysis		85$
Crystallinity
Analysis		550$
Report****		1,175$
		_______
Sub total for section 1. b.		40,335$

Corealis	Page 2 of 5
Date: April 19th, 2012

Service Agreement – A

Formulation development of RHB-105 in oral solid dosage form and manufacture of clinical supplies

Amendment 3

c. GMP Rifabutin API analytical release testing

ITEM		Cost (USD$)
ID testing
IR-Method qualification, set-up and analysis*		0$
[****]		575$
Assay
Method qualification		2,000$
Set-up		605$
Analysis		575$
Related substances
Method qualification		2,500$
Set-up**		0$
Analysis		795$
Water - Xxxx Xxxxxx Titration (USP <921>)		165$
Analysis
Limit of N-Iso Butylpiperidone (TLC)
Qualification, set-up and analysis		1,650$
Residual solvents
[****].
[****].
[****]		24,000$
Analysis		1,800$
Qualification [****]***		2,000$
Appearance
Analysis		85$
Report****		1,103$
		_______
Sub total for section 1. c.		37,853$
		_______
Total cost of the amendment		101,795$
* Already included in Service Agreement A.

Corealis	Page 3 of 5
Date: April 19th, 2012

Service Agreement – A

Formulation development of RHB-105 in oral solid dosage form and manufacture of clinical supplies

Amendment 3

** Included in the set-up cost of the Assay.

***Analysis to be outsourced to a Corealis qualified vendor. [****] in Toronto using the validated analytical methods of [****].

**** Cost for the documentation and the CofA- 3% of the total cost of the analysis.

2. COST AND PAYMENTS

2.1 The cost of the Services for the Extra Work detailed in section 1 is:

2.1.1 $101,795 if the following installments are:

· 50% at the signature of this Agreement; and

· the balance at the completion of the release testing.

OR

2.1.2 $89,783 if $89,783 is paid within 7 days from the signature of this Agreement.

2.2 The Client shall pay to Corealis the following installments in United-States currency ($USD):

3. TIMELINES FOR AMENDMENT 3

[****]

IN WITNESS THEREOF, the Parties have executed this Amendment as of the Date written above, by their authorised representatives, who by signing confirm their authority and intention to bind the Parties they represent.

Corealis	Page 4 of 5
Date: April 19th, 2012

Service Agreement – A

Formulation development of RHB-105 in oral solid dosage form and manufacture of clinical supplies

Amendment 3

Corealis Pharma Inc.		7810962
Canada Inc.
Per: /s/___________________		Per: /s/ Xxxxx Xxxxxxx PhD
Name: Xxxx Xxx, Ph.D.		Name: Xxxxx Xxxxxxx PhD
Title: President		Title: Senior director of Research

Corealis	Page 5 of 5
Date: April 19th, 2012