Under the Securities Exchange Act of 1934
(Amendment No. 4)(1)

(Name of Issuer)

(Title of Class of Securities)

(CUSIP Number)

(Name, Address and Telephone Number of Person
Authorized to Receive Notices and Communications)

(Date of Event Which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box. o

Note:  Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits.  See §240.13d-7 for other parties to whom copies are to be sent.

(1)The remainder of this cover page shall be filled out for a reporting person's initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be deemed to be "filed" for the purpose of Section 18 of the Securities Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

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EXPLANATORY NOTE

This Amendment No. 3 to the Schedule 13D amends and supplements the Schedule 13D, filed March 14, 2003 and amended on December 27, 2012, April 24, 2013 and May 8, 2013 (together, the “Schedule 13D”), by the Filing Persons (as defined below) relating to the Common Stock, par value $0.01 per share, of Acura Pharmaceuticals Inc., a New York corporation (the “Issuer”).  The Issuer is filing this amendment to the Schedule 13D solely to update the disclosures set forth therein to include the open market transactions discussed in Item 3 below.

Item 3.       Source and Amount of Funds or Other Consideration

Item 3 is hereby amended to add the following:

From May 8, 2013 through May 23, 2013, Care Capital Investments II, LP sold 1,632,966 shares of Issuer’s Common Stock and Care Capital Offshore Investments II, LP sold 112,034 shares of Issuer’s Common Stock in open market transactions.

Item 5.       Interest in Securities of the Issuer

Item 5 is hereby amended and restated as follows:

(a)                                 As of May 23, 2013, Care Capital Investments II, LP is the beneficial owner of 6,185,183 shares of the Issuer’s Common Stock, representing 13.1% of the Issuer’s shares of Common Stock outstanding (based upon 46,375,485 shares of Common Stock outstanding, as reported in the Issuer’s Quarterly Report on Form 10-Q for the quarter ended March 31, 2013 filed on May 2, 2013).  Such 6,185,183 shares of Common Stock include: (i) 5,454,624 shares of Common Stock and (ii) warrants to purchase 730,559 shares of Common Stock that are exercisable within 60 days of the date of this filing.  As of May 23, 2013, Care Capital Offshore Investments II, LP is the beneficial owner of 424,311 shares of the Issuer’s Common Stock, representing 0.9% of the Issuer’s shares of Common Stock outstanding (based upon 46,375,485 shares of Common Stock outstanding, as reported in the Issuer’s Quarterly Report on Form 10-Q for the quarter ended March 31, 2013 filed on May 2, 2013).  Such 424,311 shares of Common Stock include: (i) 374,191 shares of Common Stock and (ii) warrants to purchase 50,120 shares of Common Stock that are exercisable within 60 days of the date of this filing.  By virtue of Care Capital II, LLC’s status as general partner of Care Capital Investments II, LP and Care Capital Offshore Investments II, LP, Care Capital II, LLC may be deemed the beneficial owner of 6,609,494 shares of the Issuer’s Common Stock held by Care Capital Investments II, LP and Care Capital Offshore Investments II, LP, representing 14.0% of the Issuer’s shares of Common Stock outstanding (based upon 46,375,485 shares of Common Stock outstanding, as reported in the Issuer’s Quarterly Report on Form 10-Q for the quarter ended March 31, 2013 filed on May 2, 2013).  Such 6,609,494 shares of Common Stock include: (i) 5,828,815 shares of Common Stock and (ii) warrants to purchase 780,679 shares of Common Stock that are exercisable within 60 days of the date of this filing.  Care Capital II, LLC disclaims beneficial ownership of the securities, and this report shall not be deemed an admission that Care Capital II, LLC is the beneficial

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owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their pecuniary interest therein.

(b)                                 By virtue of its status as general partner of Care Capital Investments II, LP and Care Capital Offshore Investments II, LP, Care Capital II, LLC, may be deemed to share voting and dispositive power with respect to the 6,185,183 shares of Issuer’s Common Stock held by Care Capital Investments II, LP and 424,311 shares of Issuer’s Common Stock held by Care Capital Offshore Investments II, LP.  Care Capital II, LLC disclaims beneficial ownership of the securities and this report shall not be deemed an admission that Care Capital II, LLC is the beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their pecuniary interest therein.

(c)                                  During the past sixty days prior to the date hereof, the following transactions occurred:

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(d)                                 No person, other than Care Capital II, LLC, is known to have the right to receive or the power to direct the receipt of dividends from, or any proceeds from the sale of, the shares of Common Stock beneficially owned by each of Care Capital Investments II, LP and Care Capital Offshore Investments II, LP.

(e)                                  Not applicable.

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SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Attention:  Intentional misstatements or omissions of fact constitute Federal criminal violations
(See 18 U.S.C. 1001)

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