Arena Pharmaceuticals INC: directors' dealings · United States · SEC (Form 4)

About Arena Pharmaceuticals INC

Arena Pharmaceuticals Inc. was a United States-based biopharmaceutical company focused on small-molecule therapies for immuno-inflammatory and cardiovascular diseases. The company was founded in 1997 and was headquartered in San Diego, California, United States, with additional operating hubs in the U.S. and Europe before its acquisition. Arena’s business model was that of a research-driven clinical-stage biotech rather than a commercial, diversified pharmaceutical group. Its best-known programs included etrasimod, an oral, selective sphingosine-1-phosphate (S1P) receptor modulator developed for immune-mediated diseases, along with cardiovascular development assets such as temanogrel and APD418. Over time, Arena also explored other candidates across gastroenterology, dermatology, pain, and inflammatory conditions, reflecting a pipeline strategy aimed at high-unmet-need indications and differentiated mechanisms of action. From a competitive standpoint, Arena operated in a crowded biotech landscape where success depended on clinical data, regulatory execution, and the ability to secure strategic partnerships or a larger pharmaceutical acquirer. That outcome ultimately materialized: Pfizer announced the acquisition of Arena in December 2021 and completed it in March 2022 for about $6.7 billion in cash. As part of that transaction, Arena became a wholly owned subsidiary of Pfizer and its shares were delisted from the Nasdaq Global Select Market. Therefore, while ARNA may still appear in SEC archives and historical insider-transaction records, it is no longer an independent listed equity on NYSE/NASDAQ. For investors following SEC Form 4 activity, the practical interpretation is that Arena is a legacy ticker with historical biotech relevance rather than an active standalone public company. Its key recent corporate milestone was the Pfizer takeover, which effectively transferred the economic and development value of Arena’s pipeline into Pfizer’s inflammation and immunology franchise.