Gossamer Calls It Quits On BTK Inhibitor Following Patient Deaths

The company will devote resources to its program to develop seralutinib in pulmonary arterial hypertension after announcing that it would discontinue GB5121 in CNS lymphoma.

Gossamer is prioritizing seralutinib in pulmonary arterial hypertension after deciding to discontinue GB5121 • Source: Shutterstock

Gossamer Bio, Inc.’s decision to discontinue the development of the central nervous system-penetrant BTK inhibitor candidate GB5121 for primary CNS lymphoma follows the decision announced in its fourth quarter earnings to deprioritize the program after multiple serious adverse events, including two patient deaths in a study. But not only is the company knocked back in the BTK class, its prioritization of a pulmonary arterial hypertension (PAH) program for a different kind of drug, seralutinib, has attracted some controversy due to lackluster performance in a prior trial.

Gossamer said in a 3 April Securities and Exchange Commission filing that it had decided to terminate ongoing studies of...