Amphastar Pharmaceuticals (AMPH) vs Kiniksa Pharmaceuticals International (KNSA)
Head-to-head comparison of performance, valuation, growth, profitability and dividends. Prices delayed 15 minutes; data as of Oct 8, 2026.
Summary
Kiniksa Pharmaceuticals International (KNSA) has outperformed Amphastar Pharmaceuticals (AMPH) over the past year, gaining 104.5% versus a loss of 1.1%. Over five years, KNSA leads with a +580.9% price change compared with +33.6% for AMPH. Kiniksa Pharmaceuticals International is the larger company by market cap ($6.08 billion vs $1.09 billion), about 5.6 times the size.
On valuation, Amphastar Pharmaceuticals trades at a lower forward P/E (8.0x vs 48.2x for Kiniksa Pharmaceuticals International).
Summary generated from market data by MetaCap's automated system. Methodology
Relative performance
Percent change in share price from the first common trading day shown; excludes dividends.
Head-to-head
| Metric | AMPH | KNSA |
|---|---|---|
| Share price | $25.54 | $77.96 |
| Market cap | $1.09B | $6.08B |
| 1-day change | -1.43% | +1.13% |
| YTD return | -4.63% | +88.99% |
| 1-year return | -1.12% | +104.51% |
| 5-year return | +33.65% | +580.87% |
| P/E ratio (TTM) | 15.11 | 78.75 |
| Forward P/E | 8.03 | 48.20 |
| EPS (TTM) | $1.69 | $0.99 |
| Dividend yield | 0.00% | 0.00% |
| Annual dividend | $0.00 | $0.00 |
| Revenue (latest FY) | — | $677.56M |
| Revenue growth (YoY) | — | +60.09% |
| Net income (latest FY) | — | $59.01M |
| Gross margin | — | 88.54% |
| Operating margin | — | 11.40% |
| Net margin | — | 8.71% |
| 52-week high | $29.52 | $82.94 |
| 52-week low | $16.65 | $35.20 |
| Distance from 52-week high | -13.48% | -6.00% |
| Analyst consensus | none | strong_buy |
| Avg. price target upside | -11.90% | +25.71% |
| Average volume | 472.61K | 578.96K |
| Shares outstanding | 42.54M | 48.29M |
| Employees | 1,976 | 366 |
| Sector | Health Care | Health Care |
| Industry | Biotechnology: Pharmaceutical Preparations | Biotechnology: Pharmaceutical Preparations |
Highlighted cells mark the higher value for growth, returns, margins and yield, and the lower value for P/E ratios. Highlighting is a mechanical comparison, not a recommendation.
Key differences
- Kiniksa Pharmaceuticals International is about 5.6 times larger than Amphastar Pharmaceuticals by market value ($6.08B vs $1.09B).
- KNSA has outperformed AMPH by 105.6 percentage points over the past year.
- Kiniksa Pharmaceuticals International trades at a higher earnings multiple (78.7x vs 15.1x trailing P/E).
About Amphastar Pharmaceuticals
AMPH stock →Amphastar Pharmaceuticals, Inc., a bio-pharmaceutical company, develops, manufactures, markets, and sells generic and proprietary injectable, inhalation, and intranasal products in the United States, China, and France. It offers BAQSIMI, a dry nasal spray used in an emergency for the treatment of severe hypoglycemia; Primatene MIST, an epinephrine inhalation product for the temporary relief of mild symptoms of intermittent asthma; Glucagon for injection emergency kit; Enoxaparin, an injectable form of low molecular weight heparin for the prevention and treatment of deep vein thrombosis; and REXTOVY and Naloxone for opioid overdose.
Health Care · Biotechnology: Pharmaceutical Preparations · 1,976 employees
About Kiniksa Pharmaceuticals International
KNSA stock →Kiniksa Pharmaceuticals International, plc, a biopharmaceutical company, develops and commercializes medical therapies in the United States, the United Kingdom, and internationally. The company offers ARCALYST, an interleukin-1alpha and 1beta cytokine trap for the treatment of recurrent pericarditis, a chronic autoinflammatory cardiovascular disease and cardiac sarcoidosis.
Health Care · Biotechnology: Pharmaceutical Preparations · 366 employees
AMPH vs KNSA FAQ
Which is bigger, Amphastar Pharmaceuticals or Kiniksa Pharmaceuticals International?
Kiniksa Pharmaceuticals International (KNSA) is larger, with a market capitalization of $6.08B compared with $1.09B for Amphastar Pharmaceuticals (AMPH).
Which stock has performed better over the past year, AMPH or KNSA?
KNSA returned +104.51% over the past 12 months, compared with -1.12% for AMPH (price return, excluding dividends). Past performance does not predict future results.
Which has the lower P/E ratio, AMPH or KNSA?
AMPH has the lower trailing P/E at 15.1, versus 78.7 for KNSA. A lower P/E is not by itself a sign of a better investment; it can reflect slower expected growth or higher risk.
Are Amphastar Pharmaceuticals and Kiniksa Pharmaceuticals International in the same industry?
Yes. Both are classified in the Biotechnology: Pharmaceutical Preparations industry within the Health Care sector.