Abpro Holdings, Inc. (ABPO)

Abpro Holdings, Inc. is a clinical-stage biotechnology company working on antibody-based therapies for cancer and other serious diseases. Its operating business was founded in 2004 and is based in Woburn, Massachusetts. The company developed bispecific antibody candidates and a platform for engineering antibodies against disease targets.

The company became publicly listed in 2024 through a business combination with Atlantic Coastal Acquisition Corp. II, a special purpose acquisition company, which closed in November 2024. After the merger the company was renamed Abpro Holdings, Inc. and its shares traded on the Nasdaq Global Market under the symbol ABPO, with warrants listed as ABPWW.

Its pipeline included ABP-102, a bispecific antibody directed at HER2-expressing tumors, which Abpro advanced together with a collaboration partner. The company also pursued other programs, including an antibody for ophthalmic disease. As a pre-revenue biotechnology business, it relied on financing from investors and partners to fund development.

Like many companies that go public through SPAC mergers, Abpro faced pressure on its share price and its financial position after listing. Nasdaq staff issued determinations on September 30 and October 15, 2025 relating to listing standards. The company appealed, and after a hearing on October 30, 2025 a Nasdaq panel allowed continued listing on November 10, 2025, subject to conditions.

On February 18, 2026, the panel decided to suspend the company, and trading in its securities was suspended on February 23, 2026. Abpro appealed to the Nasdaq Listing and Hearing Review Council on March 3, 2026. The staff delisting determination became final on April 6, 2026, and the council affirmed the panel on May 26, 2026.

The Nasdaq Board declined to call the matter for review on August 12, 2026, making the decision final. Nasdaq stated that the company no longer qualified under Listing Rules 5450(a)(1), 5450(b)(2)(A) and 5450(b)(2)(C), and filed a notice of removal from listing and registration on Form 25 on September 30, 2026. The delisting took effect at the open of the market on October 12, 2026.