Protagonist Therapeutics, Inc. (PTGX) Stock Price & Analysis

Protagonist Therapeutics, Inc. (PTGX) is trading at USD 138.25, down 0.92% today, as of October 23, 2026 at 17:28 UTC (US market open; quotes may be delayed), according to Nexqual market data.

PTGX last closed at USD 139.53; today's session has ranged USD 135–139.32 on volume of 153,972 shares. Market capitalization is $8.95B, with a 52-week range of USD 73.84–160.81 (NGM). Source: Nexqual, retrieved October 23, 2026 at 17:28 UTC.

Also available as compact Markdown for AI agents: nexqual.com/PTGX.md

Key facts (PTGX)

• Last four reported quarters (through Jun 30, 2026): revenue $282M, net income $82.9M (29.4% margin), free cash flow $131M (SEC filings).
• Valuation: P/E 107.9x (avg 9.1x at the last 1 fiscal year-ends).
• 1 of 80 tracked superinvestors hold PTGX (13F, Q2 2026): 0 new, 0 added, 1 reduced, 0 unchanged.
• Insider open-market sales, last ~7 months: 9 Form 4 filings, $58.0M; 3 not under a Rule 10b5-1 plan ($13.6M); 3 by opportunistic insiders (1 outside 10b5-1 plans), 0 by routine insiders (three-year test, Cohen, Malloy & Pomorski 2012).
• Analysts: Buy (mean 1.79 on a 1–5 scale) (14 analysts), mean target USD 178.57 (range 149–225).
• Total return with dividends: 1Y +86.9% vs S&P 500 +14.4%; 5Y +343.7% vs S&P 500 +77.0%.
• Next earnings: 2026-11-05, EPS estimate USD 2.66, revenue estimate $241M.

Financials (SEC 10-K; TTM = last four 10-Q/10-K quarters) (PTGX)

Fiscal years end Dec. EPS is split-adjusted.

Valuation (price ÷ last four quarters, through Jun 30, 2026) (PTGX)

P/E 107.9x · P/S 31.7x · P/FCF 68.5x · P/B 10.6x · FCF yield 1.46% · Earnings yield 0.93%

P/E at fiscal year-ends: Dec 2024 9.1x.

Superinvestors (SEC 13F-HR, Q2 2026) (PTGX)

1 of 80 tracked investors hold PTGX. Each row is the investor's latest 13F; change is vs their prior-quarter share count.

Insider sales (SEC Form 4, open-market, last ~7 months) (PTGX)

6 of 9 under a Rule 10b5-1 trading plan (scheduled in advance). Unplanned sales were timed by the insider.

% of holdings sold = shares sold ÷ (shares sold + all holdings the insider reported on that Form 4, direct and through trusts).

Insider type follows Cohen, Malloy & Pomorski (Journal of Finance, 2012). An insider who traded the stock in the same calendar month in each of the past three years is a routine trader; one who traded in each of those years without such a pattern is an opportunistic trader. In their study, trades by opportunistic insiders predicted future returns and trades by routine insiders did not. Counts open-market purchases and sales only (SEC Form 4 codes P and S) by that insider in that company. Not investment advice.

Analysts (PTGX)

Consensus Buy (mean 1.79 on a 1–5 scale), 14 analysts; mean target USD 178.57 (low 149, high 225).

Rating changes, last 120 days:

Total return (dividends reinvested) (PTGX)

PTGX suppliers, customers and competitors (named in its 10-K)

Quoted from the company's 10-K filed Feb 25, 2026.

Companies that name PTGX in their SEC reports

PTGX customer concentration

In the period ended Dec 31, 2025, a single direct customer accounted for 100% of revenue, per the company's 10-K filed Feb 25, 2026. The company does not name it.

PTGX company outlook (results filed Aug 5, 2026)

• “PN-881 (oral IL-17 antagonist peptide): Pharmacokinetic data from the Phase 1 study supports the decision to advance PN-881 into a comprehensive Phase 2 psoriasis program, with initiation expected in early Q1 2027. o PN-881 achieved 24-hour C trough levels significantly higher than prospectively targeted IC 90 (IL-17AA, IL-17FF, IL-17AA+FF) values with once-daily oral dosing 1 ·”
• “PN-458o (dual GLP/GIP agonist peptide): IND-enabling studies are ongoing with Phase 1 initiation anticipated in the second half of 2027. ·”
• “PN-8047 (oral small molecule hepcidin functional mimetic): IND-enabling studies are ongoing, with Phase 1 initiation anticipated in Q1 2027. ·”
• “We expect our research and development expenses to increase significantly in the second half of 2026 compared to the first half of 2026.”

Quoted word-for-word from the SEC 8-K results press release.

PTGX analyst estimates and revisions

Key Statistics (as of October 23, 2026 at 17:28 UTC)

Technical Analysis (PTGX)

Nexqual's technical model rates PTGX "STRONG SELL" based on 0 bullish and 5 bearish signals across 128 daily candles, as of October 23, 2026 at 17:28 UTC.

Analyst Ratings (PTGX)

Wall Street analysts rate PTGX "Buy" based on 14 analysts, with a mean price target of USD 178.57 (range USD 149–225), per Nexqual as of October 23, 2026 at 17:28 UTC.

Earnings (PTGX)

Recent Earnings History

Source: Nexqual, October 23, 2026 at 17:28 UTC.

Financials & Fundamentals (PTGX)

Source: Nexqual, October 23, 2026 at 17:28 UTC.

Financial Health Score (PTGX)

Nexqual rates Protagonist Therapeutics, Inc.'s overall financial health "Mixed" across five dimensions, as of October 23, 2026 at 17:28 UTC.

Ownership (PTGX)

Source: Nexqual, October 23, 2026 at 17:28 UTC.

Leadership (PTGX)

Protagonist Therapeutics, Inc. is led by Dinesh V. Patel, CEO, President, Secretary & Director, per Nexqual as of October 23, 2026 at 17:28 UTC.

Major Backers & Investors (PTGX)

Notable institutional backers of Protagonist Therapeutics, Inc. include Farallon Capital Management LLC, RTW Investments LP, Wellington Management, according to Nexqual as of October 23, 2026 at 17:28 UTC.

Active Investors

Index Funds (Passive)

Source: Nexqual, October 23, 2026 at 17:28 UTC.

From Protagonist Therapeutics, Inc.'s Latest SEC 10-K Filing (filed 2026-02-25)

Key Strengths & Strategy (as disclosed to the SEC)

• Icotyde, an orally delivered IL-23R specific antagonist for the potential treatment of psoriasis, PsA and IBD indications, was discovered through our proprietary technology platform.
• Despite available treatments, significant unmet medical needs persist: Rusfertide was discovered through our proprietary technology platform.
• Our wholly-owned development candidates, PN-477 and PN-458, leverage our proprietary technology platform to target key hormonal and metabolic pathways while addressing persistent barriers to long-term treatment adherence, including gastrointestinal tolerability, the burden of chronic injections, and the potential to support improved body-composition outcomes during weight loss.
• Our proprietary technology platform is purposefully built to exploit the advantages of constrained peptides, which are much smaller than antibody-based drugs and may be delivered orally but are big enough to bind and block the difficult targets that antibodies bind and modulate.

Partnerships

• We are eligible to receive up to $630.0 million in future development and sales milestone payments, including the following potential milestones: We will also receive upward tiering royalties on net worldwide Icotyde product sales at percentages ranging from 6% to 10%.
• We discovered rusfertide, advanced it into Phase 3 development, and in early 2024 entered into a co-development and co-commercialization arrangement with Takeda Pharmaceuticals, Inc. ("Takeda") under a license and collaboration agreement entered into in January 2024.

Legal & Regulatory Risks (Item 1A, quoted)

• Our product candidates may cause undesirable side effects or have other properties adversely impacting safety that delay or prevent their regulatory approval, restrict their approved labeling, or otherwise limit their commercial opportunity.
• We rely on third parties to conduct our pre-clinical studies and clinical trials. If these third parties do not successfully carry out their contractual obligations or do not meet regulatory requirements or expected deadlines, we may not be able to obtain timely regulatory approval for or commercialize our product candidates and our business could be substantially harmed.
• Risks Related to Regulatory Process and Other Legal Compliance Matters
• Our employees, independent contractors, principal investigators, consultants and vendors may engage in misconduct or other improper activities, including noncompliance with regulatory standards and requirements, which could have a material adverse effect on our business.

Source: SEC EDGAR 10-K, official filing. Curated by Nexqual.

Peers & Related Stocks

Data source: Nexqual — market data, technical indicators, analyst consensus, earnings, SEC EDGAR filings. Last updated: October 23, 2026 at 17:28 UTC. This page is informational and not investment advice.

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