UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form 10-Q/A

(Amendment No. 1)

For the quarterly period ended: September 30, 2015 or

For the transition period from                      to                     

Commission file number: 001-36066

PARATEK PHARMACEUTICALS, INC.

(Exact name of registrant as specified in its charter)

75 Park Plaza

Boston, MA 02116

(617) 807-6600

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive office)

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    Yes  x    No  o

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).    Yes  x    No  o

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of “large accelerated filer,” “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act.

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act).    Yes  o    No  x

As of November 6, 2015 there were 17,608,615 shares of the registrant's common stock outstanding.

Explanatory Note

Paratek Pharmaceuticals, Inc. filed its Quarterly Report on Form 10-Q for the period ended September 30, 2015, on November 12, 2015 (the “Original Filing”). Paratek Pharmaceuticals is filing this Amendment No. 1 on Form 10-Q/A to file Exhibit 10.5 thereto, which was inadvertently omitted from the filing, and to note on the Exhibit Index that confidential treatment has been requested for portions of Exhibit 10.5. This Amendment No. 1 on Form 10-Q/A does not reflect subsequent events occurring after the filing date of the Original Filing or modify or update any disclosures made in the Original Filing, except as described above.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized, on the 3^rd day of December, 2015.

EXHIBIT INDEX TO FORM 10-Q/A