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Companies

OS Therapies

HER2-targeted immunotherapy for osteosarcoma

Raised to date

$11.6M

of $19.2M offered across 4 Form D filings

Still open
$7.7M
Investors
9
Last filed
Jul 16, 2026

About

Ostherapies is a clinical-stage biotechnology company focused on developing immunotherapies that activate the patient's immune system to fight HER2-expressing cancers. The firm's primary objective is to advance its lead therapy through clinical trials, initially targeting osteosarcoma, a cancer that has not seen new treatments in over three decades.

The company is pioneering a new treatment for osteosarcoma, addressing a critical unmet need that has persisted for more than 30 years, while also targeting other aggressive solid tumors.

Funding

Jun 2025DecJun 2026
Now

$9.3M round, first sold Jun 2026: $1.6M sold, $7.7M still open

  • Security to be acquiredFiled Jul 16, 2026Form D
    $1.6M/ $9.3M
  • Security to be acquiredFiled Mar 6, 2026Form D
    $2M/ $2M
  • EquityFiled Sep 10, 2025Form D
    $3.8M/ $3.8M
  • EquityFiled Jul 16, 2025Form D
    $4.2M/ $4.2M

Product

Lead Immunotherapy Candidate

Clinical-Stage Immunotherapy

The company's flagship product is an immunotherapy drug currently in human clinical trials. It is engineered to activate the body's immune system to recognize and eliminate cancer cells that express the HER2 protein, with an initial indication for osteosarcoma and potential application across other solid tumors.

  • Novel immune activation mechanism
  • Targets HER2-expressing cancer cells
  • Addresses a significant treatment gap in osteosarcoma for both children and adults

Built for

Patients with HER2-expressing solid tumors, supported by oncologists and patient advocacy groups.

People on file