With Concentra Biosciences expanding its stock influence in Pliant Therapeutics and Acelyrin, the two biotechs have shored up their corporate defences against a potential acquisition.
Both Pliant and Acelyrin have implemented their own “poison pill” plans. The rule changes mean that if a single investor secures 10% or more of either company’s stock, it will trigger certain changes that could make it harder for a buyer to hoover up the remaining shares.
Acelyrin was explicit that it had made the changes in response to the “continued rapid accumulation” of 8.8% of the biotech’s stock by Tang Capital Partners. Acelyrin had already turned down a proposal earlier this month to be bought out by Tang-owned Concentra Biosciences, which came in the middle of plans for Acelyrin to merge with immune-mediated disease specialist Alumis.
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Pliant didn’t namecheck Concentra when erecting its own stock defence, only stating that it is “intended to reduce the likelihood that any entity, person or group is able to gain control of Pliant through open market accumulation without paying all stockholders an appropriate control premium or providing the board sufficient opportunity to make informed judgments and take actions that are in the best interests of all stockholders.”
However, a Securities and Exchange Commission filing shows that earlier this month Tang and its various entities together accrued 9.6% of Pliant’s stock.
Tang has a track record of swooping in to try to acquire struggling biotechs—with mixed results. The company bought Jounce Therapeutics and Theseus Pharmaceuticals in 2023 but had its advances rejected by Atea Pharmaceuticals, Rain Oncology, LianBio and Kezar Life Sciences.
In one instance back in 2023, Quince Therapeutics resorted to a similar poison pill strategy to ward off potential buyers, one of which was Concentra.
Pliant seems to fit the bill for a potential Concentra target, with the biotech’s idiopathic pulmonary fibrosis treatment bexotegrast struggling with increased adverse events in a phase 2b/3 trial this year.