SECOND AMENDMENT TO INVESTORS’ RIGHTS AGREEMENT

Exhibit 10.1

SECOND AMENDMENT TO

INVESTORS’ RIGHTS AGREEMENT

     This Second Amendment to Investors’ Rights Agreement (this “Second Amendment”) is made and entered into as of December 20, 2006, among SIRION HOLDINGS, INC. (f/k/a Tenby Pharma Inc.), a Delaware corporation (the “Company”), and the investors signatory hereto (each such investor is a “Investor” and all such investors are, collectively, the “Investors”). All capitalized terms set forth in this Second Amendment but not otherwise defined herein shall have the meaning ascribed thereto in the Original Agreement.

     WHEREAS, the Company and the Investors have previously entered into that certain Investors’ Rights Agreement dated September 13, 2006, as amended by that certain First Amendment to Investors’ Rights Agreement dated as of November 15, 2006 (collectively as amended, the “Original Agreement”);

     WHEREAS, the Company and the Investors desire to amend certain provisions of the Original Agreement to provide for an additional extension of the required time period within which the Company is required to comply with the requirements of Section 2 of the Original Agreement.

     NOW, THEREFORE, in consideration of the mutual covenants contained in this Agreement, and for other good and valuable consideration the receipt and adequacy of which are hereby acknowledged, the Company and the Investors agree as follows:

     1. New Definitions. Section 1 of the Original Agreement is hereby amended by adding the following new definitions thereto (where the same would appear in alphabetical order), to wit:

      “Commission” means the U.S. Securities and Exchange Commission, and any successor federal agency or commission that is delegated administrative authority with respect to the federal securities laws, and the staff thereof.”

      “Securities Act” means the Securities Act of 1933, as amended.”

     2. Definition of “Filing Date”. The term “Filing Date” as defined in Section 1 of the Original Agreement is hereby amended by deleting the current definition in its entirety and substituting the following therefor, to wit:

“Filing Date” means, (a) with respect to the initial Registration Statement required to be filed pursuant to Section 2, the earlier of (i) January 31, 2007, and (ii) the date that is the tenth (10th) day following the closing by the Company of a private offering of equity and/or debt securities pursuant to a financing transaction that results in gross proceeds to the Company of at least $5,000,000, and (b) with respect to any additional Registration Statements that may be required pursuant to Section 3, the 30^th day following the date on which the Company receives a valid request for registration pursuant to Section 3.”

     3. No Other Changes. Except as expressly amended hereby, the Original Agreement shall remain in full force and effect and is hereby ratified and affirmed by the parties.

     4. Counterparts. This Second Amendment may be executed in counterparts, each of which shall constitute an original and all of which together shall constitute one and the same instrument. Any party hereto may execute this Second Amendment by signing any one counterpart. A facsimile copy (including telephonic, portable digital format or other) of this Second Amendment and any signature(s) hereon shall be considered for all purposes as an original.

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2

     IN WITNESS WHEREOF, the parties have executed this Investors’ Rights Agreement as of the date first written above.

		SIRION HOLDINGS, INC.
		(f/k/a Tenby Pharma Inc.)
		By:		/s/ Xxxxx Xxxxxx
				Name: Xxxxx Xxxxxx
				Title: CEO and President

Address for Notice:

0000 Xxxxxx Xxxx Xxxxx, Xxxxx 000
Xxxxx, Xxxxxxx 00000
Facsimile No.: (000) 000-0000
Telephone No.: (000) 000-0000
Attn: Xxxxx Xxxxxx

with a copy (which shall not constitute notice) to:

Xxxx, Xxxx and Xxxxxxxxx, P.A.
000 Xxxx Xxxxxxx Xxxxxxxxx, Xxxxx 0000
Xxxxx, Xxxxxxx 00000
Facsimile No.: (000) 000-0000
Telephone No.: (000) 000-0000
Attn: Xxxx Xxxxx, Esq.

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Signature pages for the Investors follow.]

		NORTH SOUND LEGACY INSTITUTIONAL FUND LLC
		By:		North Sound Capital LLC; Manager
		By:		/s/ Xxxxxx X. Xxxxx
				Name: Xxxxxx X. Xxxxx
				Title: General Counsel

Address for Notice:

00 Xxxxxxxxx Xxxx
Xxxxxxxxx, Xxxxxxxxxxx 00000
Facsimile No.: (000) 000-0000
Telephone No.: (000) 000-0000
Attn: Xxxxxx X. Xxxxx, Esq.

with a copy (which shall not constitute notice) to:

Proskauer Rose LLP
0000 Xxxxxxxx
Xxx Xxxx, Xxx Xxxx 00000
Facsimile No.: (000) 000-0000
Telephone No.: (000) 000-0000
Attn: Xxxx X. Xxxxxxx, Esq.

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Signature pages of other Investors to follow.]

		NORTH SOUND LEGACY INTERNATIONAL LTD.
		By:		North Sound Capital LLC; Investment Advisor
		By:		/s/ Xxxxxx X. Xxxxx
				Name: Xxxxxx X. Xxxxx
				Title: General Counsel

Address for Notice:

00 Xxxxxxxxx Xxxx
Xxxxxxxxx, Xxxxxxxxxxx 00000
Facsimile No.: (000) 000-0000
Telephone No.: (000) 000-0000
Attn: Xxxxxx X. Xxxxx, Esq.

with a copy (which shall not constitute notice) to:

Proskauer Rose LLP
0000 Xxxxxxxx
Xxx Xxxx, Xxx Xxxx 00000
Facsimile No.: (000) 000-0000
Telephone No.: (000) 000-0000
Attn: Xxxx X. Xxxxxxx, Esq.

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Signature pages of other Investors to follow.]

		AVALON VENTURES VI, L.P.
		By:		Avalon Ventures GP, LLC
				its General Partner
		By:		/s/ Xxxxx X. Xxxxxxxx
				Name: Xxxxx X. Xxxxxxxx
				Title: Managing Member

Address for Notice:

c/o Sytera II, Inc.
000 Xxxxxxxx Xxxxxx, Xxxxx 000
Xx Xxxxx, XX 00000
Facsimile No.: (000) 000-0000
Telephone No.:
Attn:

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Signature pages of other Investors to follow.]

		AVALON VENTURES VI GP FUND, LLC
		By:		Avalon Ventures GP, LLC
				its General Partner
		By:		/s/ Xxxxx X. Xxxxxxxx
				Name: Xxxxx X. Xxxxxxxx
				Title: Managing Member

Address for Notice:

c/o Sytera II, Inc.
000 Xxxxxxxx Xxxxxx, Xxxxx 000
Xx Xxxxx, XX 00000
Facsimile No.: (000) 000-0000
Telephone No.:
Attn:

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Signature pages of other Investors to follow.]

		AVALON VENTURES VII, L.P.
		By:		Avalon Ventures VII GP, LLC
				its General Partner
		By:		/s/ Xxxxx X. Xxxxxxxx
				Name: Xxxxx X. Xxxxxxxx
				Title: Managing Member

Address for Notice:

c/o Sytera II, Inc.
000 Xxxxxxxx Xxxxxx, Xxxxx 000
Xx Xxxxx, XX 00000
Facsimile No.: (000) 000-0000
Telephone No.:
Attn:

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Signature pages of other Investors to follow.]

/s/ Xxxxx Xxxxxx Xxxxx Xxxxxx

Address for Notice:

c/o Tenby Pharma Inc.
0000 Xxxxxx Xxxx Xxxxx, Xxxxx 000
Xxxxx, XX 00000
Facsimile No.: (000) 000-0000
Telephone No.: (000) 000-0000
Attn: Xxxxx Xxxxxx

with a copy (which shall not constitute notice) to:

Xxxx, Xxxx and Xxxxxxxxx, P.A.
000 Xxxx Xxxxxxx Xxxxxxxxx, Xxxxx 0000
Xxxxx, XX 00000
Facsimile No.: (000) 000-0000
Telephone No.: (000) 000-0000
Attn: Xxxx Xxxxx, Esq.

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Signature pages of other Investors to follow.]

/s/ Xxxxx Xxxxx Xxxxx Xxxxx

Address for Notice:

c/o Tenby Pharma Inc.
0000 Xxxxxx Xxxx Xxxxx, Xxxxx 000
Xxxxx, XX 00000
Facsimile No.: (000) 000-0000
Telephone No.: (000) 000-0000
Attn: Xxxxx Xxxxx

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Signature pages of other Investors to follow.]

		XXXXXX FAMILY LIMITED PARTNERSHIP
		By:		/s/ Xxxxxxx X. Xxxxxx
				Name: Xxxxxxx X. Xxxxxx, M.D.
				Title: Partner

Address for Notice:

c/o Sytera II, Inc.
000 Xxxxxxxx Xxxxxx, Xxxxx 000
Xx Xxxxx, XX 00000
Facsimile No.: (000) 000-0000
Telephone No.:
Attn: Xxxxxxx X. Xxxxxx, M.D.

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Signature pages of other Investors to follow.]

		THE XXXXXXX FAMILY TRUST
		By:		/s/ Xxx Xxxxxxx
				Name: Xxx Xxxxxxx, Ph.D.
				Title: Trustee

Address for Notice:

c/o Sytera II, Inc.
000 Xxxxxxxx Xxxxxx, Xxxxx 000
Xx Xxxxx, XX 00000
Facsimile No.: (000) 000-0000
Telephone No.:
Attn: Xxx Xxxxxxx, Ph.D.

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Signature pages of other Investors to follow.]

		PHARMABIO DEVELOPMENT INC.
		(D/B/A NOVAQUEST)
		By:		/s/ Xxxxx X. Xxxx
				Name: Xxxxx X. Xxxx
				Title: Vice President

Address for Notice:

0000 Xxxxxxxxxx Xxxxx
Xxxxxxxxxx Xxxxxxxx, Xxxxx 000
Xxxxxx, XX 00000
Facsimile No.: (000) 000-0000
Telephone No.: (000) 000-0000
Attn: President

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