Janux shares halve despite still strong Phase I data

In a week light on clinical catalysts, Janux was the biggest mover, falling 53% and shedding over $1 billion in market cap after Phase I data from its masked bispecific antibody left investors wondering why the therapy’s strong PSA50 reduction did not translate to longer progression-free survival. The question now is whether JANX007 will still beat the competition, and if so, by how much.

Janux Therapeutics Inc. (NASDAQ:JANX) reported Tuesday that its conditionally active bispecific T cell engager, JANX007, led to 7.8-8.9 months of radiographic progression-free survival in 109 PSMA+ metastatic castration-resistant prostate cancer (mCRPC) patients. Patients in the Phase Ia part of the study were heavily pretreated, while those in the Phase Ib part were taxane naive...