Protagonist Reports First Quarter 2022 Financial Results and Provides Corporate Update Initiated Phase 3 VERIFY study of rusfertide in polycythemia vera, reaffirming rusfertide in PV as the Company's primary point of foc

Reports First Quarter 2022 Financial Results and Provides Corporate Update

Phase 3 VERIFY study of rusfertide in polycythemia vera, reaffirming rusfertide in PV as the Company's primary point of focus

topline results from the Phase 2 IDEAL study of PN-943 in ulcerative colitis with consistent treatment effects at the lower 150 mg BID

dose across key endpoints; formally engaged PJT Partners to lead external partnering efforts

payment of $25 million received from Janssen upon dosing of third patient in the Phase 2B FRONTIER-1 study of PN-235 in psoriasis

Calif., May 4, 2022 - Protagonist Therapeutics (Nasdaq:

PTGX) ("Protagonist" or "the Company") today reported financial results for the first quarter of 2022 ended March 31,

2022 and provided a corporate update.

has been a period of important clinical results and strategic focus," said Dinesh V. Patel, Ph.D., President and Chief Executive

Officer of Protagonist. "Today, we reaffirm rusfertide as the primary focus of our organization's resources, time, and attention.

This prioritization is based on the compelling data we have obtained to date and the potential of this therapeutic peptide to transform

the treatment of patients with polycythemia vera. We are committed to the execution of all critical activities related to the successful

completion of the Phase 3 VERIFY study. We look forward to a productive ongoing dialogue with regulators, and sharing important data

from our ongoing rusfertide studies at upcoming medical meetings."

Dr. Patel continued:

"Recently, we released topline data from the Phase 2 IDEAL study of PN-943, our oral, gut-restricted alpha-4 beta-7-integrin antagonist

drug candidate in development for ulcerative colitis. We are pleased and encouraged with the positive results across different measures

in the lower dose arm, and are scheduled for an oral presentation at the Digestive Disease Week (DDW) conference later this month. Based

on the consistency of our results with previous studies with other agents that target the integrin-MadCAM pathway, and the strong concordance

across different measures in the lower dose arm of this Phase 2 study, we believe that PN-943 may represent a substantial commercial

opportunity and merits further clinical development. We intend to pursue further clinical development in collaboration with a large pharma

partner or through a structured financing arrangement. We have now formally engaged PJT Partners to facilitate a collaboration arrangement

with a pharmaceutical company. In addition to commercialization capabilities, we believe that a partner can add the financial and development

resources required to maximize the potential benefit to patients that could be provided by this important therapeutic candidate. At the

current time, our planned expenses for PN-943 are related to finalizing the Phase 3 study design with regulators and completing the ongoing

manufacturing of clinical trial materials to support study initiation. We expect these activities to have a minimal impact on our cash

resources and we retain our prior guidance of cash runway through the end of 2024."

Quarter 2022 Recent Developments and Upcoming Milestones

Subcutaneous Injectable Hepcidin Mimetic for Polycythemia Vera (PV) and Other Blood Disorders

Oral, gut-restricted, alpha-4-beta-7 Integrin Antagonist for Ulcerative Colitis (UC)

Oral IL-23 Receptor Antagonist

Quarter 2022 Financial Results

Protagonist Therapeutics

is a biopharmaceutical company with multiple peptide-based new chemical entities in different stages of clinical development, all derived

from the Company's proprietary technology platform.

Protagonist's pipeline

includes rusfertide, an investigational, injectable hepcidin mimetic currently in the REVIVE Phase 2 proof-of-concept clinical trial

for polycythemia vera (PV), the PACIFIC Phase 2 study in PV subjects with high hematocrit levels, and a recently completed Phase 2a study

for hereditary hemochromatosis. The Company has opened sites and initiated patient screening for VERIFY, a single, global Phase 3 randomized,

placebo-controlled trial evaluating the efficacy and safety of a once weekly, subcutaneously self-administered dose of rusfertide for

patients living with PV.

The IDEAL Phase 2 study

of PN-943 in moderate-to-severe ulcerative colitis concluded in April 2022. The results of this Phase 2 study supported advancement

of the 150-milligram dose of PN-943 into a Phase 3 study. Efforts to secure a partner to support the financing and execution of a Phase

3 study are underway.

Protagonist has granted

Janssen an exclusive worldwide license to research, develop and commercialize oral IL-23 receptor antagonists based on the Company's

intellectual property. Current development efforts are centered on PN-235, discovered by Protagonist and further developed in collaboration

with Janssen. FRONTIER 1, a Phase 2b multicenter, randomized, placebo controlled, dose-ranging study to evaluate the safety and efficacy

of PN-235 for the treatment of moderate-to-severe plaque psoriasis, commenced in early 2022.

Forward-Looking Statements

press release contains forward-looking statements for purposes of the safe harbor provisions of the Private Securities Litigation Reform

Act of 1995. Forward-looking statements include statements regarding our intentions or current expectations concerning, among other things,

our plans to secure a collaborative partner to support further clinical development of PN-943, the potential commercial opportunity of

PN-943, the clinical development of rusfertide and potential milestones related to PN-235. In some cases, you can identify these statements

by forward-looking words such as "anticipate," "believe," "may," "will," "expect,"

or the negative or plural of these words or similar expressions. Forward-looking statements are not guarantees of future performance

and are subject to risks and uncertainties that could cause actual results and events to differ materially from those anticipated, including,

but not limited to, our ability to develop and commercialize our product candidates, our ability to earn milestone payments under our

collaboration agreements, the impact of the current COVID-19 pandemic on our discovery and development efforts, the impact of the ongoing

military conflict in Ukraine and Russia on any future studies, our ability to use and expand our programs to build a pipeline of product

candidates, our ability to obtain and maintain regulatory approval of our product candidates, our ability to operate in a competitive

industry and compete successfully against competitors that have greater resources than we do, and our ability to obtain and adequately

protect intellectual property rights for our product candidates. Additional information concerning these and other risk factors

affecting our business can be found in our periodic filings with the Securities and Exchange Commission, including under the heading

"Risk Factors" contained in our most recently filed periodic reports on Form 10-K and Form 10-Q filed with the Securities

and Exchange Commission. Forward-looking statements are not guarantees of future performance, and our actual results of operations, financial

condition and liquidity, and the development of the industry in which we operate, may differ materially from the forward-looking statements

contained in this press release. Any forward-looking statements that we make in this press release speak only as of the date of

this press release. We assume no obligation to update our forward-looking statements, whether as a result of new information, future

events or otherwise, after the date of this press release.

Jami Taylor - j.taylor@ptgx-inc.com

Kevin Murphy - protagonist@argotpartners.com

Media: Joshua R. Mansbach

- protagonist@argotpartners.com

Condensed Consolidated Statements of Operations

in thousands except share and per share data)

Stock-Based Compensation

Selected Condensed Consolidated Balance Sheet Data