SEC Form 4

FORM 4		UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940	OMB APPROVAL OMB Number: 3235-0287 Estimated average burden hours per response: 0.5
	Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person* ORBIMED ADVISORS LLC (Last) (First) (Middle) 767 3RD AVENUE 30TH FLOOR (Street) NEW YORK NY 10017 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol ARYx Therapeutics, Inc. [ ARYX ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director X 10% Owner Officer (give title below) Other (specify below)
	3. Date of Earliest Transaction (Month/Day/Year) 11/14/2008
	4. If Amendment, Date of Original Filed (Month/Day/Year)	6. Individual or Joint/Group Filing (Check Applicable Line) Form filed by One Reporting Person X Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	11/14/2008		P		1,214,646	A	(4)	3,340,139(1)	I	See footnote(2)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Common Stock Warrants (right to buy)	$2.64	11/14/2008		P		364,395		11/14/2008	11/14/2013	Common Stock	364,395	(4)	364,395(3)	I	See footnote(2)

1. Name and Address of Reporting Person* ORBIMED ADVISORS LLC (Last) (First) (Middle) 767 3RD AVENUE 30TH FLOOR (Street) NEW YORK NY 10017 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* ISALY SAMUEL D (Last) (First) (Middle) 767 THIRD AVE. 30TH FLOOR (Street) NEW YORK NY 10017 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

Explanation of Responses:

1. The amount shown represents (i) 2,237,773 shares of Common Stock held directly by Caduceus Private Investments, LP ("Caduceus"), (ii) 46,580 shares of Common Stock held directly by OrbiMed Associates, LLC ("Associates"), and (iii) 1,055,786 shares of Common Stock held directly by UBS Juniper Crossover Fund, L.L.C. ("Juniper"), all of which are deemed to be affiliates of the Reporting Persons.

2. OrbiMed Advisors LLC "Advisors")is a registered adviser under the Investment Advisors Act of 1940,as amended,that acts as an investment adviser to certain collective investment funds which hold shares of the Issuer. Samuel D. Isaly, a natural person, owns a controlling interest in Advisors and OrbiMed Capital GP I, LLC ("Capital").Capital is the general partner of Caduceus. Advisors is the managing member of Associates and is a joint venture member of the investment adviser of Juniper with full trading discretion. Pursuant to certain agreements and relationships, Advisors and Capital have discretionary investment managment authority with respect to the assets of Caduceus, Associates, and Juniper. Such authority includes the power to vote and otherwise dispose of securities purchased by Caduceus, Associates and Juniper. The Reporting Persons disclaim beneficial ownership of all of these securities except to the extent of their respective pecuniary interest therein

3. Consists of warrants to purchase (i) 244,131 shares held by Caduceus (ii) 5,082 shares held by Associates, and (iii) 115,182 shares held by Juniper, all of which are deemed to be affiliates of the Reporting Persons.

4. These securities were purchased as part of a private placement transaction by the Issuer pursuant to the terms of a certain securities purchase agreement, dated November 11, 2008, a copy of which was filed as an exhibit to the Issuer's Current Report on Form 8-K filed on November 12, 2008. The combined purchase price of each share of common stock and each warrant to purchase 0.30 of a share of common stock issued in the private placement is $2.2375.

	/s/Samuel D. Isaly, President	11/18/2008
	/s/Samuel D. Isaly	11/18/2008
	** Signature of Reporting Person	Date
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