{"entity":{"id":"harpoon-therapeutics","kind":"company","name":"Harpoon Therapeutics","aka":[],"tldr":"Harpoon built small T-cell engager proteins that link a patient's T cells to tumour cells, including HPN328, which targets DLL3 on small cell lung cancer and neuroendocrine tumours. Merck bought the company in early 2024 for about $680 million.","summary":"Harpoon Therapeutics was a South San Francisco clinical-stage company that developed T-cell engagers on its Tri-specific T cell Activating Construct (TriTAC) platform and the ProTriTAC prodrug platform, which keeps the engager inactive until it reaches the tumour. Lead candidate HPN328 is a DLL3-targeting T-cell engager evaluated in patients with small cell lung cancer and neuroendocrine tumours. On 8 January 2024 Merck agreed to acquire Harpoon for $23.00 per share in cash, an approximate total equity value of $680 million, and the merger completed on 11 March 2024, after which Harpoon's Nasdaq listing (HARP) ended. Merck said it would evaluate HPN328 in combinations with its pipeline. The harpoontx.com domain now redirects to merck.com.","asOf":"2026-09-10","links":[{"label":"Official website","url":"https://www.merck.com/"},{"label":"Merck to acquire Harpoon (8-K exhibit 99.2, January 2024)","url":"https://www.sec.gov/Archives/edgar/data/1708493/000119312524003927/d715256dex992.htm"},{"label":"Completion of merger (8-K, March 2024)","url":"https://www.sec.gov/Archives/edgar/data/1708493/000119312524064395/d808382d8k.htm"}],"tags":[],"related":[],"cancers":["sclc","neuroendocrine"],"sections":["immunotherapy"],"technologies":["t-cell-engager"],"targets":["dll3","cd3"],"drugs":[],"companies":[],"institutions":[],"pathways":[],"terms":[],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":["Former Nasdaq ticker HARP."],"hq":"South San Francisco, CA","country":"US","companyType":"biotech","website":"https://www.merck.com/","stage":"acquired","investors":[],"funding":[{"round":"Acquisition","year":2024,"amountUsd":680000000,"source":"https://www.sec.gov/Archives/edgar/data/1708493/000119312524003927/d715256dex992.htm","note":"$23.00 per share in cash, approximate total equity value $680 million; announced 8 January 2024, completed 11 March 2024"}],"acquiredBy":"merck"},"route":"/companies/harpoon-therapeutics/","neighbours":{"cancer":[{"id":"neuroendocrine","kind":"cancer","name":"Neuroendocrine tumours","route":"/cancers/neuroendocrine/"},{"id":"sclc","kind":"cancer","name":"Small-cell lung cancer","route":"/cancers/sclc/"}],"section":[{"id":"immunotherapy","kind":"section","name":"Immunotherapy","route":"/fronts/immunotherapy/"}],"technology":[{"id":"t-cell-engager","kind":"technology","name":"T-cell engagers (bispecific)","route":"/technologies/t-cell-engager/"}],"target":[{"id":"cd3","kind":"target","name":"CD3","route":"/targets/cd3/"},{"id":"dll3","kind":"target","name":"DLL3","route":"/targets/dll3/"}],"company":[{"id":"merck","kind":"company","name":"Merck & Co. (MSD)","route":"/companies/merck/"}],"trial":[{"id":"nct04471727","kind":"trial","name":"A Study in Participants With Advanced Cancers Associated With Expression of DLL3 (MK-6070-001/HPN328-4001)","route":"/trials/nct04471727/"}]}}