Summit Therapeutics Inc. 4

Co-CEO Mahkam Zanganeh purchased 3,810,000 shares of Summit Therapeutics Inc. common stock at $13.12 per share (≈$50 million total).

On June 12, 2026, Summit Therapeutics Inc. Co-Chief Executive Officer Mahkam Zanganeh reported an open‑market purchase of 3,810,000 shares of Summit Therapeutics common stock at an average price of $13.12 per share, for an estimated total cost of approximately $49.97 million. Following this significant insider purchase, beneficial ownership (largely through indirect holdings) increased to 573,883,879 shares held indirectly via her spouse, 25,824,474 shares held indirectly via the Mahkam Zanganeh Revocable Trust (with the reporting person as trustee), 76,680 shares held indirectly through an immediate family member, and 10,199,776 shares held indirectly via the Shaun Zanganeh Irrevocable Trust, plus 31,000 shares held directly. The filer disclaims beneficial ownership of certain of these securities except to the extent of her pecuniary interest, but the transaction still reflects a very large incremental capital commitment by the Co-CEO.

Filing Facts

CIK

1599298

Ticker

SMMT

Form

4

Source Type

sec

Accession

0001507650-26-000007

Alert Tier

8