Protagonist Therapeutics, Inc. (PTGX) P/E Ratio History
Historical price-to-earnings valuation from 2024 to 2025
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Valuation Context
How does the current P/E compare to historical and market benchmarks?
P/E Ratio Analysis
As of February 28, 2026, Protagonist Therapeutics, Inc. (PTGX) trades at a price-to-earnings ratio of -44.9x, with a stock price of $92.08 and trailing twelve-month earnings per share of $-2.05.
The current P/E is 204% below its 5-year average of 43.1x. Over the past five years, PTGX's P/E has ranged from a low of 9.2x to a high of 107.1x, placing the current valuation at the 0th percentile of its historical range.
Compared to the Healthcare sector median P/E of 23.7x, PTGX trades at a 290% discount to its sector peers. The sector includes 224 companies with P/E ratios ranging from 0.0x to 184.4x.
Relative to the broader market, PTGX trades at a notable discount to the S&P 500 median P/E of 26.2x. Investors should consider the company's growth prospects, competitive position, and earnings quality when evaluating whether the current valuation is justified.
For a comprehensive intrinsic value estimate using discounted cash flow analysis, see our PTGX DCF Valuation Calculator →
Note: P/E ratio is just one valuation metric. It does not account for balance sheet strength, cash flow quality, or growth sustainability. Always conduct comprehensive due diligence before making investment decisions.
Peer Comparison
P/E metrics vs. Immunology and Inflammation Therapies peers
| Company | Market Cap | P/E Ratio | PEG Ratio | EPS Growth (1Y) |
|---|---|---|---|---|
ARGXargenx SE | $47B | 60.0 | -Best | +348% |
TGTXTG Therapeutics, Inc. | $5B | 200.6 | -Best | +76% |
KNSAKiniksa Pharmaceuticals, Ltd. | $3B | 59.3 | -Best | +225% |
APLSApellis Pharmaceuticals, Inc. | $3B | 116.4 | -Best | +111% |
GLPGGalapagos N.V. | $2B | 5.9Lowest | -Best | +333% |
AUPHAurinia Pharmaceuticals Inc. | $2B | 6.8 | -Best | +5167%Best |
GYREGyre Therapeutics, Inc. | $711M | 164.8 | -Best | +104% |
RIGLRigel Pharmaceuticals, Inc. | $615M | 35.1 | -Best | +169% |
Peers sorted by market capitalization. P/E below peers may indicate undervaluation or lower growth expectations. Consider PEG ratio for growth-adjusted comparison.
Historical P/E Data
Quarterly P/E ratios calculated from closing price and TTM EPS
| Quarter | Date | Price | TTM EPS | P/E Ratio | vs Avg |
|---|---|---|---|---|---|
| FY2025 Q3 | $66.43 | $0.62 | 107.1x | +149% | |
| FY2025 Q2 | Mon Jun 30 2025 00:00:00 GM | $55.27 | $0.70 | 79.0x | +83% |
| FY2025 Q1 | Mon Mar 31 2025 00:00:00 GM | $48.36 | $0.75 | 64.5x | +50% |
| FY2024 Q4 | $38.60 | $4.20 | 9.2x | -79% | |
| FY2024 Q3 | Mon Sep 30 2024 00:00:00 GM | $45.00 | $2.66 | 16.9x | -61% |
| FY2024 Q2 | Sun Jun 30 2024 00:00:00 GM | $34.65 | $2.62 | 13.2x | -69% |
| FY2024 Q1 | Sun Mar 31 2024 00:00:00 GM | $28.93 | $2.44 | 11.9x | -72% |
Average P/E for displayed period: 43.1x
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Start ComparisonFrequently Asked Questions
Is PTGX stock overvalued or undervalued?
PTGX trades at -44.9x P/E, below its 5-year average of 43.1x. At the N/A percentile of historical range, the stock is priced at a discount to its own history.
How does PTGX's valuation compare to peers?
Protagonist Therapeutics, Inc. P/E of -44.9x compares to sector median of 23.7x. The discount suggests lower growth expectations or higher risk.
What is PTGX's PEG ratio?
PTGX PEG ratio is N/A. Above 2.0 indicates premium valuation relative to growth rate. Historical P/E data spans 2024-2025.