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Published on: September 20, 2019
Randomised clinical trial: exploratory phase 2 study of ONO-2952 in diarrhoea-predominant irritable bowel syndrome
W E Whitehead1, K Duffy2, J Sharpe2
1Division of Gastroenterology and Hepatology, Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
Background:
ONO-2952 is a novel and selective inhibitor of translocator protein 18 kDa that reduces stress-induced defecation and visceral hyperalgesia in rat models.
Aim:
To evaluate the efficacy and safety of ONO-2952 in females with irritable bowel syndrome with diarrhoea in an exploratory proof-of-concept study.
Methods:
A randomised, double-blind, placebo-controlled study was conducted at 49 US centres. Two hundred subjects with irritable bowel syndrome with diarrhoea (Rome III criteria) were randomised to ONO-2952 20 mg, or 60 mg, or placebo. Subjects recorded irritable bowel syndrome symptoms daily during a 2-week baseline period, the 4-week treatment period and for 4 weeks post-treatment. The co-primary endpoints were change from baseline to week 4 in abdominal pain, stool consistency and stool frequency.
Results:
Improvements in irritable bowel syndrome symptoms were seen with ONO-2952 over placebo in per-protocol analyses for all three co-primary endpoints, but these did not reach statistical significance at the 5% level. The largest improvement was seen with ONO-2952 60 mg. ONO-2952 was well tolerated with a safety profile similar to that of placebo. Most adverse events were mild or moderate in severity and not treatment related.
Conclusion:
ONO-2952 showed evidence of clinical efficacy in reducing irritable bowel syndrome-related symptoms in female subjects with irritable bowel syndrome with diarrhoea, and further evaluation is, therefore, warranted to assess its potential as a treatment for irritable bowel syndrome with diarrhoea (NCT01844180).
Insights
ONO-2952, a novel translocator protein inhibitor, showed potential in reducing irritable bowel syndrome with diarrhea symptoms in women. Further studies are needed to confirm its efficacy and safety as a treatment.
Area of Science:
- Gastroenterology
- Pharmacology
Background:
- ONO-2952 is a novel, selective inhibitor of translocator protein 18 kDa.
- Preclinical studies in rats indicate ONO-2952 reduces stress-induced defecation and visceral hyperalgesia.
Purpose of the Study:
- To evaluate the efficacy and safety of ONO-2952 in female patients with irritable bowel syndrome with diarrhea (IBS-D).
- An exploratory proof-of-concept study to assess ONO-2952's potential therapeutic benefit.
Main Methods:
- Randomized, double-blind, placebo-controlled trial at 49 US centers.
- 200 female subjects with IBS-D (Rome III criteria) received ONO-2952 (20 mg or 60 mg) or placebo.
- Daily symptom recording for 2 weeks baseline, 4 weeks treatment, and 4 weeks post-treatment.
- Co-primary endpoints: change in abdominal pain, stool consistency, and stool frequency from baseline to week 4.
Main Results:
- Per-protocol analyses showed improvements in IBS-D symptoms with ONO-2952 over placebo for all co-primary endpoints, but not statistically significant.
- The 60 mg ONO-2952 dose showed the largest improvement.
- ONO-2952 was well tolerated, with a safety profile similar to placebo; adverse events were mostly mild/moderate and not treatment-related.
Conclusions:
- ONO-2952 demonstrated evidence of clinical efficacy in alleviating IBS-D symptoms in female subjects.
- Further investigation is warranted to confirm ONO-2952's therapeutic potential for IBS-D.
- Clinical trial identifier: NCT01844180.
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