| $385M | ||
| $350M | ||
| $215M | ||
| $94M | ||
| $82M | ||
| $62M |
Buys | $22,969,461 | 7 | 100 |
Sells | $0 | 0 | 0 |
| Xia Yu | director | 1 | $10M | 0 | $0 | $10M |
| DUGGAN ROBERT W | Co-Chief Executive Officer | 3 | $6.48M | 0 | $0 | $6.48M |
| Zanganeh Mahkam | Co-Chief Executive Officer | 3 | $6.48M | 0 | $0 | $6.48M |
Summit Therapeutics Inc., a biopharmaceutical company, discovers, develops, and commercializes medicines to treat infectious diseases in the United States and Latin America. It conducts clinical programs focusing on Clostridioides difficile infection (CDI). The company's lead product candidate is ridinilazole, an orally administered small molecule antibiotic that is in Phase III clinical trials for the treatment of CDI. It also offers SMT-738, for combating multidrug resistant infections primarily carbapenem-resistant Enterobacteriaceae infections; and DDS-04 series for the potential treatment of infections caused by the Enterobacteriaceae. The company was founded in 2003 and is based in Cambridge, Massachusetts.
Over the last 12 months, insiders at Summit Therapeutics Inc. have bought $22.97M and sold $0 worth of Summit Therapeutics Inc. stock.
On average, over the past 5 years, insiders at Summit Therapeutics Inc. have bought $120.73M and sold $0 worth of stock each year.
Highest buying activity among insiders over the last 12 months: Xia Yu (director) — $10M. DUGGAN ROBERT W (Co-Chief Executive Officer) — $6.48M. Zanganeh Mahkam (Co-Chief Executive Officer) — $6.48M.
The last purchase of 533,617 shares for transaction amount of $10M was made by Xia Yu (director) on 2025‑10‑21.
| 2025-10-21 | Xia Yu | director | 533,617 0.0719% | $18.74 | $10M | -5.84% | ||
| 2025-10-21 | Zanganeh Mahkam | Co-Chief Executive Officer | 26,680 0.0036% | $18.74 | $499,983 | -5.84% | ||
| 2025-10-21 | DUGGAN ROBERT W | Co-Chief Executive Officer | 26,680 0.0036% | $18.74 | $499,983 | -5.84% | ||
| 2025-09-11 | Zanganeh Mahkam | Co-Chief Executive Officer | 5,000 0.0007% | $18.07 | $90,350 | -2.45% | ||
| 2025-09-11 | DUGGAN ROBERT W | Co-Chief Executive Officer | 5,000 0.0007% | $18.07 | $90,350 | -2.45% | ||
| 2025-09-10 | Zanganeh Mahkam | Co-Chief Executive Officer | 333,394 0.0451% | $17.68 | $5.89M | +3.07% | ||
| 2025-09-10 | DUGGAN ROBERT W | Co-Chief Executive Officer | 333,394 0.0451% | $17.68 | $5.89M | +3.07% | ||
| 2024-03-27 | Zanganeh Mahkam | Chief Executive Officer | 80,321 0.0113% | $3.72 | $298,594 | +378.13% | ||
| 2024-03-26 | Dhingra Ankur | Chief Financial Officer | 100,000 0.0143% | $3.75 | $375,000 | +378.07% | ||
| 2024-03-26 | Zanganeh Mahkam | Chief Executive Officer | 30,000 0.0043% | $3.75 | $112,500 | +378.07% | ||
| 2023-12-13 | Dhingra Ankur | Chief Financial Officer | 20,400 0.0027% | $2.17 | $44,254 | +236.97% | ||
| 2023-12-12 | Zanganeh Mahkam | Chief Executive Officer | 5,000 0.0007% | $2.07 | $10,350 | +257.05% | ||
| 2023-10-13 | Soni Manmeet Singh | Chief Operating Officer | 2.98M 0.4265% | $1.68 | $5M | +163.99% | ||
| 2023-03-08 | Zanganeh Mahkam | Co-CEO & President | 23.53M 4.2977% | $1.05 | $24.7M | +26.97% | ||
| 2023-03-07 | Dhingra Ankur | Chief Financial Officer | 196,362 0.0395% | $1.05 | $206,180 | +39.86% | ||
| 2023-03-06 | DUGGAN ROBERT W | Chief Executive Officer | 376.49M 75.2052% | $1.05 | $395.31M | +38.49% | ||
| 2022-08-16 | DUGGAN ROBERT W | Chief Executive Officer | 94.85M 61.3078% | $0.97 | $92M | +70.30% | ||
| 2022-08-16 | Zanganeh Maky | Co-CEO & President | 1.03M 0.6664% | $0.97 | $999,997 | +70.30% | ||
| 2022-08-16 | Dhingra Ankur | Chief Financial Officer | 37,685 0.0244% | $0.97 | $36,554 | +70.30% | ||
| 2021-05-12 | DUGGAN ROBERT W | Chief Executive Officer | 11.37M 12.0109% | $5.24 | $59.56M | -6.40% |
| Xia Yu | director | 32057147 4.3062% | $480.54M | 1 | 0 | |
| DUGGAN ROBERT W | Co-Chief Executive Officer | 76680 0.0103% | $1.15M | 7 | 0 | +47.98% |
| Zanganeh Mahkam | Co-Chief Executive Officer | 76680 0.0103% | $1.15M | 9 | 0 | +184.02% |
| Soni Manmeet Singh | Chief Operating Officer | 2976190 0.3998% | $44.61M | 1 | 0 | +163.99% |
| Dhingra Ankur | Chief Financial Officer | 354958 0.0477% | $5.32M | 4 | 0 | +181.3% |
| Powell David Jonathan | Chief Scientific Officer | 0 0% | $0 | 0 | 5 |
$961,890,236 | 276 | 22.46% | $21.28B | |
$211,610,344 | 91 | 38.45% | $10.85B | |
$2,765,836 | 72 | 20.00% | $11.17B | |
$108,876,545 | 67 | 72.81% | $9.55B | |
$88,307,390 | 38 | -1.70% | $10.06B | |
$19,233,721 | 36 | 70.14% | $11.77B | |
$1,801,511 | 23 | 18.58% | $9.03B | |
$415,090,639 | 19 | -14.04% | $13.11B | |
$143,065,458 | 17 | 8.01% | $18.85B | |
$152,272,932 | 16 | -10.78% | $19.38B | |
$1,279,017 | 16 | 51.12% | $9.2B | |
Summit Therapeutics Inc. (SMMT) | $627,701,115 | 15 | 145.68% | $11.16B |
$284,820 | 10 | 45.67% | $14.01B | |
$11,898,979 | 10 | 54.58% | $7.91B | |
$948,235 | 8 | 15.56% | $10.45B | |
$41,376,000 | 4 | -12.07% | $7.97B | |
$40,276,273 | 4 | 34.57% | $17.96B | |
$36,900,000 | 3 | -9.12% | $10.99B | |
$999,989 | 1 | 262.16% | $16.02B |
| Increased Positions | 124 | +43.97% | 12M | +12.35% |
| Decreased Positions | 123 | -43.62% | 7M | -7.27% |
| New Positions | 46 | New | 2M | New |
| Sold Out Positions | 51 | Sold Out | 3M | Sold Out |
| Total Postitions | 283 | +0.35% | 103M | +5.08% |
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| State Street Corp | $111,461.00 | 0.86% | 6.36M | +2M | +58.35% | 2025-09-30 |
| Price T Rowe Associates Inc /Md/ | $79,520.00 | 0.61% | 4.54M | +633,675 | +16.23% | 2025-09-30 |
| Geode Capital Management, Llc | $54,886.00 | 0.42% | 3.13M | +197,920 | +6.74% | 2025-09-30 |
| Morgan Stanley | $33,758.00 | 0.26% | 1.93M | +1M | +200.13% | 2025-09-30 |
| Pictet Asset Management Holding Sa | $28,105.00 | 0.22% | 1.6M | -559,710 | -25.87% | 2025-09-30 |
| Norges Bank | $24,350.00 | 0.19% | 1.39M | +1M | +1,289.86% | 2025-06-30 |