Arena Pharmaceuticals announced full long-term results of its OASIS extension study, confirming that once-daily oral etrasimod leads to sustained clinical responses and favorable safety for up to 46 weeks in patients with moderate to severe ulcerative colitis (UC).
The findings were shared at United European Gastroenterology (UEG) Week, Oct.19-23 in Barcelona, Spain, in a poster titled “Long-term Efficacy and Safety of Etrasimod for Ulcerative Colitis: Results from the Open-label Extension of the OASIS Study“.
“We are delighted to see that most patients who achieved clinical response, clinical remission, or endoscopic improvement at week 12 experienced sustained or improved effects up to week 46 with etrasimod 2 mg in the open-label extension of our Phase 2 OASIS trial. Etrasimod also demonstrated a favorable safety profile, consistent with safety findings reported in the double-blind portion of OASIS,” Preston Klassen, Arena’s executive vice president, head of research and development, said in a press release.
Etrasimod (APD334) is an investigational treatment under development by Arena for immune-mediated and inflammatory diseases such as UC, Crohn’s disease, and atopic dermatitis. It is an oral, selective modulator of sphingosine 1-phosphate (S1P) receptors, designed to retain immune cells, specifically certain lymphocytes, inside lymph nodes so that fewer of them are available to enter the blood and contribute to tissue inflammation and damage.
Arena’s open-label extension study (NCT02536404) evaluated for an additional 34 weeks the safety and efficacy of etrasimod in adults with moderate to severe active UC who completed induction therapy in the Phase 2 OASIS trial, a 12-week randomized and placebo-controlled study (NCT02447302).
In the extension study, all patients received 2-mg tablets of etrasimod once daily regardless of their prior response or being in the placebo group during the OASIS trial.
A total of 118 patients rolled over to the extension part, 92 of whom (82%) completed the study. These patients were exposed to etrasimod for up to 46 weeks — 12 weeks on the main trial plus 34 weeks in the extension study.
At the end of treatment, 70% of patients had a clinical response, meaning they either experienced a complete disappearance (clinical remission) or reduction in endoscopy findings, rectal bleeding, and stool signs.
Clearance of UC signs, or clinical remission, was seen in 35%, and endoscopic improvements occurred in 45% of patients.
This represents an increase of 30% in the proportion of patients responding favorably to etrasimod, compared with the 12-week OASIS trial, in which fewer patients (40%) had a clinical response.
Among the subjects who responded to the treatment or achieved remission after 12 weeks, 87% showed sustained response, and 60% showed sustained remission after 46 weeks of treatment.
As to proof of estrasimod’s mechanism of action — which works to keep certain lymphocytes from reaching the blood — median lymphocyte reduction was 44.6% at week 12 and 42.9% at the end of the extension study, for patients receiving a 2-mg dose.
Etrasimod also demonstrated a favorable safety profile and no new safety findings were reported. Treatment-related adverse events, most of mild or moderate severity, occurred in 60% of patients.
Nine percent of patients left treatment because of side effects, including worsening disease, atrial fibrillation (a type of abnormal heart rhythm), or headache. However, no study discontinuations related to bradycardia (slow heart rate) or atrioventricular block (interruption of impulse transmission from the upper to the lower chambers of the heart).
The researchers said the findings show that “clinical response, clinical remission, or endoscopic improvement observed with etrasimod 2 mg at week 12 was sustained or improved up to week 46 in most patients.”
Klassen said, “These data support the growing body of evidence that etrasimod has potential as a safe and effective treatment for the sustained management of UC. We look forward to providing updates as we advance our global Phase 3 ELEVATE UC program.”
Arena is currently recruiting patients at sites in the United States and abroad for its Phase 3 ELEVATE UC 52 trial (NCT03945188), which will confirm the safety and efficacy of etrasimod for patients ages 16–80 with moderate or severe UC.
After a 28-day screening period, patients will receive etrasimod as a 2 mg once-daily oral capsule for 12 weeks (induction phase), followed by treatment for 40 weeks (maintenance phase) or a matching placebo. For more information about trial contacts and locations, click here.
We are sorry that this post was not useful for you!
Let us improve this post!
Tell us how we can improve this post?