Janux loses some shine

Janux is valued at $1.8bn based on highly curated datasets in small patient numbers, and now some shine is coming off the masked T-cell engager specialist, with a Monday update raising questions about cytokine release syndrome with its lead project, JANX007. The company dribbled out some more data from the phase 1 Engager-PSMA-01 trial in late-line castration-resistant prostate cancer, while announcing expansion into taxane-naive patients – but more interesting was the disclosure of a CRS-mitigation strategy. Janux didn’t give CRS numbers in its latest update, only saying that safety was consistent with the previous data drop in December; at that time grade 3 or higher CRS was seen in 6% of patients. Still, even then Janux didn’t give absolute numbers of adverse events. In December Janux focused on 16 pre-Pluvicto patients receiving 2-9mg; now it has zoomed in on those getting 6mg or 9mg, where it touted 7.9-month median rPFS (versus the current 7.5 months in the original 16 patients). While some analysts have said JANX007 could be the best asset in development for CRPC, Janux still has much to prove. The group’s stock fell 9% on Monday, and Janux’s market cap is well off the $3bn it reached in December.

Evolving data with JANX007 in Engager-PSMA-01

Notes: *pre-Pluvicto pts receiving target doses of 2-9mg; **depending on starting dose given; ^1 confirmed & 3 unconfirmed PRs. Source: OncologyPipeline & company releases.