Harpoon Therapeutics, Inc. Stock: price and insider trades · United States · SEC (Form 4)

About Harpoon Therapeutics, Inc.

Harpoon Therapeutics, Inc. was a United States-based biopharmaceutical company formerly listed on the NASDAQ market in the United States. The company was founded in the 2010s and was headquartered in California. Its strategy was highly focused on oncology R&D, with a clinical-stage profile rather than a commercial-stage business model. In practical terms, Harpoon was built around the development of novel immuno-oncology assets designed to harness the immune system against cancer, making it a typical small-cap biotech centered on scientific value creation, pipeline advancement, and strategic optionality. ([merck.com](https://www.merck.com/news/merck-to-acquire-harpoon-therapeutics-further-diversifying-oncology-pipeline/?utm_source=openai)) Harpoon’s core business line was the development of T-cell engager therapies, a modality intended to bring immune cells into close proximity with tumor cells and trigger targeted killing. Its lead asset was gocatamig, previously known as HPN328 and later MK-6070, a DLL3-targeting T-cell engager. DLL3 is a cancer-associated target that is particularly relevant in small-cell lung cancer and some neuroendocrine tumors, which positions the asset in areas of significant unmet medical need. Harpoon also had additional pipeline work in development, but the company’s market identity was largely defined by this lead program and its broader T-cell engager platform. ([merck.com](https://www.merck.com/news/merck-to-acquire-harpoon-therapeutics-further-diversifying-oncology-pipeline/?utm_source=openai)) From a competitive standpoint, Harpoon operated in one of the most crowded and scientifically demanding areas of biotech: immuno-oncology. Its differentiation came from its platform design and its focus on novel tumor targets, rather than from scale, revenue diversification, or commercial infrastructure. That makes the company a useful example of a research-led biotech whose valuation depended heavily on clinical readouts, partner interest, and strategic M&A appeal. In that respect, Harpoon’s story culminated in its acquisition by Merck, one of the world’s leading pharmaceutical groups, which validated the strategic relevance of the pipeline. Merck announced the transaction in January 2024 and completed it on March 11, 2024. ([merck.com](https://www.merck.com/news/merck-to-acquire-harpoon-therapeutics-further-diversifying-oncology-pipeline/?utm_source=openai)) For investors, the most important current fact is that Harpoon no longer trades independently: it was merged into Merck and delisted from NASDAQ after closing. Historically, the company’s geographic footprint was concentrated in the United States, with its operating base in California and its business model aimed at global oncology markets. Recent corporate developments therefore revolve not around standalone growth, but around the acquisition process, the transfer of assets into Merck, and the subsequent integration of Harpoon’s lead oncology program into a larger pharmaceutical pipeline. In short, Harpoon transitioned from an independent clinical-stage biotech into an acquired asset within Merck’s oncology franchise. ([sec.gov](https://www.sec.gov/Archives/edgar/data/310158/000031015825000014/R9.htm?utm_source=openai))