Protagonist Reports First Quarter 2025 Financial Results and Provides Corporate Update Positive top line results from rusfertide Phase 3 VERIFY trial in polycythemia vera (PV) announced; full data selected for oral prese

Protagonist Reports First

Quarter 2025 Financial Results and Provides Corporate Update

Positive top line results

from rusfertide Phase 3 VERIFY trial in polycythemia vera (PV) announced; full data selected for oral presentation during plenary session

be held June 2nd at 8AM EDT to discuss rusfertide data presented at ASCO

dataset from Phase 3 ICONIC-LEAD trial with icotrokinra in patients with moderate-to-severe plaque psoriasis (PsO) presented at the 2025

AAD Meeting in March; data from adolescent subset presented at World Congress of Pediatric Dermatology in April

top line results from icotrokinra Phase 2b ANTHEM trial in moderately to severely active ulcerative colitis (UC) announced in March, data

to be presented at medical conference later in 2025

Cash, cash equivalents

and marketable securities of $697.9 million as of March 31, 2025, anticipated to provide cash runway through at least end of 2028

Calif., May 6, 2025 - Protagonist Therapeutics (Nasdaq: PTGX) ("Protagonist" or "the

Company") today reported financial results for the first quarter ended March 31, 2025,

and provided a corporate update.

"Protagonist is off to a very strong

2025 with multiple transformational events in the first quarter for our two late-stage partnered assets, rusfertide and icotrokinra which

are progressing to NDA filings by year end," said Dinesh V. Patel, Ph.D., the Company's President and CEO. "We look

forward to presenting data from rusfertide's Phase 3 VERIFY study at a plenary session at ASCO on June 1st. We're

very pleased with the highly positive results from the icotrokinra Phase 2b ANTHEM study in ulcerative colitis which lay the foundation

for additional studies in both UC and Crohn's. We are continuing to increasingly focus on advancement of our pre-clinical candidates

including the oral IL-17 antagonist PN-881, as well as additional candidates emerging from our oral anti-obesity and oral hepcidin programs.

We are fortunate to be in a very strong cash position, allowing us to independently and rapidly progress our early-stage pipeline into

value-creating clinical safety and proof-of-concept studies starting with PN-881 in 2025."

Quarter 2025 Recent Developments and Upcoming Milestones

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

Abstract accepted for presentation

at the Plenary Session at the 2025 American Society of Clinical Oncology (ASCO).

International Investors:1-412-317-6026

webcast link for the event can be found here: https://viavid.webcasts.com/starthere.jsp?ei=1718556&tp_key=360d3b714d

A replay of the presentation

will be available on the Company's Investor Relations Events and Presentations webpage following the event.

1 A responder is a patient who completed weeks 0-32 of

the study, was not phlebotomy eligible and did not receive a phlebotomy during weeks 20-32. To meet phlebotomy eligibility, patients

in the study were required to have: confirmed hematocrit 45% that was 3% higher than their baseline hematocrit value, or hematocrit

Icotrokinra (JNJ-2113): Oral IL-23 Receptor Antagonist

First Quarter 2025 Financial Results

Protagonist Therapeutics is a discovery

through late-stage development biopharmaceutical company. Two novel peptides derived from Protagonist's proprietary discovery platform

are currently in advanced Phase 3 clinical development, with New Drug Application submissions to the FDA potentially in 2025. Icotrokinra

(formerly, JNJ-2113) is a first-in-class investigational targeted oral peptide that selectively blocks the Interleukin-23 receptor ("IL-23R")

which is licensed to J&J Innovative Medicines ("JNJ"), formerly Janssen Biotech, Inc. Following icotrokinra's

joint discovery by Protagonist and JNJ scientists pursuant to the companies' IL-23R collaboration, Protagonist was primarily responsible

for development of icotrokinra through Phase 1, with JNJ assuming responsibility for development in Phase 2 and beyond. Rusfertide, a

mimetic of the natural hormone hepcidin, is currently in Phase 3 development for the rare blood disorder polycythemia vera (PV). Rusfertide

is being co-developed and will be co-commercialized with Takeda Pharmaceuticals pursuant to a worldwide collaboration and license agreement

entered in 2024 under which the Company remains primarily responsible for development through NDA filing. The Company also has a number

of pre-clinical stage oral drug discovery programs addressing clinically and commercially validated targets, including IL-17 oral peptide

antagonist PN-881, oral hepcidin program, and oral obesity program.

information on Protagonist, its pipeline drug candidates and clinical studies can be found on the Company's website at https://www.protagonist-inc.com/.

on Forward-Looking Statements

This 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 the potential benefits of icotrokinra and rusfertide, the timing of icotrokinra and rusfertide clinical trials,

and timing of developments and announcements in our discovery programs. 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

with Janssen and Takeda, 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.

Investor Relations Contact

Media Relations Contact

ENTENTE Network of Companies

+1 833 500 0061 ext 1

PROTAGONIST THERAPEUTICS, INC.

Condensed Consolidated Statements of Operations

(Amounts in thousands except share and per share

includes non-cash stock-based compensation expense.

(Unaudited, in thousands)

PROTAGONIST THERAPEUTICS, INC.

Selected Condensed Consolidated Balance Sheet

(Unaudited, In thousands)