8-K

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): August 6, 2018

PROTAGONIST THERAPEUTICS, INC.

(Exact name of registrant as specified in its charter)

Delaware	001-37852	98-0505495
(State or other jurisdiction of incorporation)	(Commission File Number)	(IRS Employer Identification No.)

Protagonist Therapeutics, Inc.

7707 Gateway Blvd., Suite 140

Newark, California 94560-1160

(Address of principal executive offices, including zip code)

(510) 474-0170

(Registrant’s telephone number, including area code)

Not Applicable

(Former name or former address, if changed since last report.)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

oWritten communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

oSoliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

oPre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

oPre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company x

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.   x

Item 7.01Regulation FD Disclosure.

Attached hereto as Exhibit 99.1 is a copy of a presentation that the Company intends to use in connection with a conference call on August 6, 2018.

The information in this Current Report on Form 8-K, including the attached Exhibit 99.1, is being furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liability of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act, whether made before or after the date hereof, except as expressly set forth by specific reference in such filing to this Current Report on Form 8-K.

Item 9.01Financial Statements and Exhibits.

(d) Exhibits

99.1Protagonist Therapeutics, Inc. Presentation dated August 6, 2018

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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 hereunto duly authorized.

	Protagonist Therapeutics, Inc.
Dated: August 6, 2018
	By:	/s/ Thomas P. O’Neil
		Thomas P. O’Neil
		Chief Financial Officer

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EX-99.1

Exhibit 99.1

Dinesh V. Patel, PhD President & CEO August 06, 2018 Conference Call CONFIDENTIAL

PTG-100: Oral, α4β7-specific, GI-restricted, Targeted Therapy for IBD Randomized, double-blind, placebo-controlled adaptive parallel design 12 week induction study, q.d. dosing 2 Phase 2b PROPEL Study in Ulcerative Colitis Patients 300 mg QD Placebo 900 mg QD 150 mg QD Dose B Placebo Dose A Moderate to severe active UC n ~260, ~100 sites Pre-interim n = 65 Interim Analysis and/or Futile outcome declared by independent DMC in late March 2018 based on pre-specified criteria of primary end point of clinical remission Trial discontinued No safety concerns noted Unusually high placebo observed Comprehensive data review completion and Go/No-go decision by Q3 Post-interim n ~175-195 ✗

Human Error in Endoscopy Reads from CRO led to Unusually High Placebo Effect 3 Ruled out operational misconduct or trial design issues as contributing factors to futility Identified central endoscopy read issues early on in the process Interim analysis reads by CRO (n=65) Unusually high placebo remitters (4/17, 23.5%); historic norm is ~6% Technical errors in endoscopy scoring All 4 initial placebo remitters were by a single reader Re-read by CRO lead reader/trainer confirmed the errors by original reader in both placebo and treatment arms Re-read found 2/17 (11.7%) placebo remitters; this indicated non-futile outcome Dialog with numerous KOLs and recommendation to conduct totally blinded and independent re-reads with a new CRO (Robarts Clinical Trials)

PTG-100 has Signals of Clinical Efficacy and Merits further Development 4 Blinded re-read of full dataset (n=83) by independent CRO (Robarts) Placebo in sync with historic norms (1/21, 4.8%) Clinical efficacy comparable to other competitive IBD drugs (9-16%) Histopathology and PD biomarker analysis Histopath correlations with endoscopy responses and clinical remissions PD biomarkers illustrate dose dependent target engagement PTG-100 merits further clinical development in UC

Re-analysis based on Robarts Endoscopy Re-Reads (n = 83) 5 Dataset Summary Placebo rates decrease to ‘historical norms’ 900 mg q.d. shows signals of clinical efficacy Similar to historical norms of efficacy for IBD drugs (next slide) Blinded endoscopy re-reads on complete data set by Robarts Criteria Placebo 150 mg 300 mg 900 mg # Patients 21 22 21 19 Clinical Remission 1 (4.8%) 2 (9.1%) 2 (9.5%) 3 (15.8%) Endoscopy Response 1 (4.8%) 2 (9.1%) 3 (14.3%) 3 (15.8%)

PTG-100 Efficacy Similar to Other IBD Targeted Therapy Drugs 6 *Anti-MadCam mAb No central read endoscopy (Entyvio) a4b7 integrin Oral/S1P1 Oral/JAK N= 905 234 132 65 81 43 284 73 225 149 19 21 Injectable Oral Injectable a4b7/aEb7 Injectable MAdCAM 900 mg qd

PTG-100 Phase 2 PROPEL Study A human error in endoscopy reads led to a futile outcome PTG-100 shows signals of clinical efficacy in UC patients Robarts endoscopy re-reads Histopath and PD data Current data warrants further clinical development of PTG-100 7 Final Interim Analysis Conclusions

PTG-100 Recommended for Further Clinical Development Further development encouraged by Protagonist, KOLs, and Investors Request an FDA meeting to discuss a Phase 2/3 study Present key findings from Ph 2 PROPEL study at a medical conference 8 Next Steps Stage 1 N = 83 Stage 2 N = 160-180 Ph 2A Ph 2B discontinued Revised interim Go-decision ✔ Next Clinical Trial Design Phase 2b/3 registrational study pending FDA discussion Propel Ph 2 UC Trial

PTG-100 Oral, α4β7-specific, GI-restricted, Targeted Therapy for IBD 9 Oral Oral, once daily, needle-free, targeted therapy Offers better convenience and compliance Specific Safe Novel Therapy IBD specific mechanism: a4b7 integrin Proven mechanism: mAb Entyvio approved in 2014 GI localized MOA: a4b7-integrin & MAdCAM -1 GI-restricted drug with minimal blood exposure (<1%), potentially minimizing toxicity risks PTG-100 is the only oral, a4b7-integrin specific drug in clinical development Transformative oral targeted therapy treatment paradigm Mono oral targeted therapy Combo therapy with other oral IBD drugs Vs.

Corporate Update Recent financing reflects investor confidence and provides funding through mid-2020. 10 2018 PTG-100: Ph2b UC interim Futile Q1 Comprehensive data review completed; Q3 recommended for further development PTG-200: Janssen Ph1 completion 2H Ph2 IND filing for Crohn’s disease Q4 PTG-300: Ph2 b-Thalassemia initiation Q4 Protagonist’s Peptide Assets Proprietary Peptide Technology Platform