Exhibit 3.1

AMENDED AND RESTATED

CERTIFICATE OF INCORPORATION

OF

SAGENT PHARMACEUTICALS, INC.

ARTICLE I

Name

The name of the corporation is Sagent Pharmaceuticals, Inc. (the “Corporation”).

ARTICLE II

Address; Registered Office and Agent

The address of the Corporation’s registered office is 160 Greentree Drive, Suite 101 in the City of Dover, County of Kent, 19904; and the name of its registered agent at such address is National Registered Agents, Inc.

ARTICLE III

Purposes

The purpose of the Corporation is to engage in any lawful act or activity for which corporations may be organized under the General Corporation Law of the State of Delaware (the “DGCL”).

ARTICLE IV

Number of Shares

The total number of shares of stock that the Corporation shall have authority to issue is 1,000, all of which shall be shares of Common Stock with the par value of $0.01 per share.

ARTICLE V

Election of Directors

Unless and except to the extent that the By-laws of the Corporation (the “By-laws”) shall so require, the election of directors of the Corporation need not be by written ballot.

ARTICLE VI

Limitation of Liability

To the fullest extent permitted under the DGCL, as amended from time to time (but, in the case of any such amendment, only to the extent that such amendment permits the Corporation to provide broader rights than permitted prior thereto), no director of the Corporation shall be personally liable to the Corporation or its stockholders for monetary damages for breach of fiduciary duty as a director. Any amendment or repeal of this Article VI shall not adversely affect any right or protection of a director of the Corporation hereunder in respect of any act or omission occurring prior to the time of such amendment or repeal.

ARTICLE VII

Adoption, Amendment or Repeal of By-Laws

The Board of Directors of the Corporation is authorized to adopt, amend or repeal the By-laws.

ARTICLE VIII

Certificate Amendments

The Corporation reserves the right at any time, and from time to time, to amend or repeal any provision contained in this Amended and Restated Certificate of Incorporation, and add other provisions authorized by the laws of the State of Delaware at the time in force, in the manner now or hereafter prescribed by applicable law; and all rights, preferences and privileges of whatsoever nature conferred upon stockholders, directors or any other persons whomsoever by and pursuant to this Amended and Restated Certificate of Incorporation (as amended) are granted subject to the rights reserved in this Article.

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