Shares of Prometheus Biosciences (NASDAQ: RXDX) ended the week on a high note after releasing phase 2 results and pricing a $500 million underwritten public offering. The company saw its market cap triple on the week, closing Friday's trading session at $110.68 per share, up more than 175% from its opening price of $39.79 on Monday.

On Wednesday, the company released results from its ARTEMIS-UC Phase 2 and APOLLO-CD Phase 2a studies of PRA023, which both demonstrated strong efficacy and favorable safety results. The company said that based on the totality of the data in the two studies, it intends to advance PRA023 into Phase 3 studies for ulcerative colitis (UC) and Crohn’s disease (CD) in 2023.

The Phase 2 ARTEMIS-UC clinical trial was a study to evaluate the effectiveness and safety of a drug called PRA023 in patients with moderate-to-severely active ulcerative colitis (UC) who have not responded well to other treatments. The trial lasted for 12 weeks and involved comparing PRA023 to a placebo.

The company says that the results showed that PRA023 was effective in achieving the primary and secondary endpoints of the study, including clinical, endoscopic, histologic, and patient-reported outcome measures. 100% of patients treated with PRA023 completed the study, compared to 89.6% of those in the placebo group. PRA023 was also well tolerated, with no serious adverse events or other issues reported. The company is conducting further analysis of the drug in a subset of patients who tested positive for a certain biomarker.

Meanwhile, the Phase 2a APOLLO-CD clinical trial was a study to evaluate the effectiveness and safety of a drug called PRA023 in patients with moderate-to-severely active Crohn's disease (CD) who have not responded well to other treatments. The trial lasted for 12 weeks and involved PRA023 being given to patients without a placebo group.

The results showed that PRA023 was effective in achieving clinical remission and endoscopic response in a high proportion of patients. PRA023 was also well tolerated, with no serious adverse events reported.

The study also showed that a different genetic marker algorithm was more effective in predicting which patients would respond to PRA023. The company plans to use this new algorithm in future clinical studies for CD.

“We are beyond enthusiastic with these study results and what they could mean for patients suffering from IBD. The performance of PRA023 in both UC and Crohn’s patients has surpassed our expectations,” said Mark McKenna, Chairman and CEO of Prometheus Biosciences. “We believe PRA023 and our precision medicine approach has the potential to change the paradigm of IBD treatment and we look forward to discussions with regulatory agencies as we prepare to advance into Phase 3 studies in Ulcerative Colitis and Crohn’s Disease.”

As a result of positive data, Prometheus plans to advance PRA023 into pivotal development in 2023, following discussions with regulators. The full data sets from these studies will be presented at a future medical meeting.

Following the phase 2 results news on Wednesday, Prometheus announced on Thursday an upsized $500 million underwritten public offering that will consist of 4.55 million shares sold at $110 per share. The company expects gross poceeds from the offering to be approximately $500 million. The offering is expected to close on or about December 13, 2022

Shares of Prometheus Biosciences trade on the NASAQ under the symbol RXDX. For more information visit www.prometheusbiosciences.com.