Lilly agrees to acquire Scorpion Therapeutics' PI3K-alpha program

Eli Lilly and Company said on January 13, 2025, that it will acquire the PI3Kα inhibitor program from Scorpion Therapeutics, a private biotechnology company, in a deal that could pay Scorpion shareholders up to $2.5 billion in cash ^[1]. The agreement covers STX-478, an experimental once-daily pill being tested in a Phase 1/2 clinical trial for breast cancer and other advanced solid tumors ^[1].

The $2.5 billion figure includes an upfront payment plus additional payments if the drug hits certain regulatory and sales milestones, meaning Lilly may pay less than the full amount if the drug does not reach those markers ^[1]. As part of the deal, Scorpion will also spin off a separate company to hold its employees and other pipeline drugs that are not part of the PI3Kα program. That new company will be owned by Scorpion's current shareholders, with Lilly taking a minority stake, and will be led by Scorpion's chief executive, Adam Friedman ^[1].

STX-478 targets a genetic mutation found in a meaningful share of hormone-positive breast cancers. According to Lilly, the drug could potentially apply to 30% to 40% of people with this type of breast cancer ^[1]. Jacob Van Naarden, who leads Lilly's oncology unit, said the drug's design allows it to target cancerous cells while sparing healthy ones, which the companies say could mean better tumor control with fewer side effects than existing drugs that work on the same biological pathway ^[1]. Friedman said Lilly's scale and experience in breast cancer treatment could speed up STX-478's development ^[1].

The transaction still needs to clear standard closing conditions before it is final, and Lilly said it will decide how to account for the deal under standard accounting rules once it closes ^[1]. Citi is advising Lilly on the deal, while Centerview Partners and Morgan Stanley are advising Scorpion ^[1].

Why it matters for patients

This deal does not involve Ozempic, Wegovy, Mounjaro, Zepbound, Rybelsus, or Foundayo. It is an oncology transaction, and Lilly is the same company that sells the GLP-1 and dual GIP/GLP-1 medicines many readers take or are considering. The deal shows Lilly investing heavily outside diabetes and obesity care, in this case in breast cancer treatment, which is a separate part of its business ^[1].

For patients on GLP-1 or GIP/GLP-1 drugs, this specific acquisition has no direct bearing on drug supply, pricing, or approvals for weight management or diabetes treatments. It is included here because it reflects the scale of Lilly's corporate activity and deal-making during this period, which readers may want to track as part of understanding the company behind their medication ^[1].

STX-478 is still an experimental drug in early-stage human testing. It has not been approved by the Food and Drug Administration for any use, and its safety and effectiveness are not yet established outside of clinical trials ^[1]. Whether or when it might become an available treatment for breast cancer patients is not yet known from this announcement.

What happens next

The acquisition was announced January 13, 2025, and remains subject to customary closing conditions with no specific closing date given in the announcement ^[1]. STX-478 continues to be evaluated in an ongoing Phase 1/2 clinical trial for breast cancer and other advanced solid tumors ^[1]. No timeline for further clinical trial results, regulatory filings, or potential approval was included in the source material.