Why Prometheus Biosciences (RXDX) Stock Price Is Skyrocketing Today?

Prometheus Biosciences Inc RXDX has reported encouraging results from ARTEMIS-UC Phase 2 and APOLLO-CD Phase 2a studies of PRA023 for ulcerative colitis (UC) and Crohn's disease (CD).
The studies demonstrated strong efficacy and favorable safety results.
Prometheus intends to advance PRA023 into Phase 3 studies for UC and CD in 2023.
Phase 2 ARTEMIS-UC 12-week trial in patients with moderate-to-severely active UC met the primary and all ranked secondary endpoints, including clinical, endoscopic, histologic, and patient-reported outcome measures in Cohort 1.
26.5% of patients on PRA023 achieved clinical remission, compared to 1.5% on placebo, for a placebo-adjusted clinical remission rate of 25.0% on the primary endpoint.
36.8% of patients on PRA023 achieved endoscopic improvement vs. 6.0%.
All secondary endpoints met with statistical significance.
The expansion cohort (Cohort 2) to further assess the treatment effect of PRA023 in CDx+ patients will continue to enroll, with data expected in Q2 2023.
Phase 2a APOLLO-CD 12-week study in moderate-to-severely active CD showed that 26.0% of patients on PRA023 achieved endoscopic response compared to the 12% prespecified historical placebo rate.
49.1% of patients on PRA023 achieved clinical remission vs. 16%.
PRA023 was well tolerated in both studies.
Price Action: RXDX shares are up 235.80% at $118.50 during the premarket session on the last check Wednesday.

Prometheus Biosciences Stock Skyrockets After Favorable Data From Ulcerative Colitis, Crohn's Disease Studies