CinPhloro Pharma, A CinRx Portfolio Company, Dosed First Participant in Phase 2 enviva Study of CIN-103 for IBS-D

CIN-103 is a novel formulation of phloroglucinol designed to sustain exposure, maintain efficacy and reduce dosing frequency

The enviva study will evaluate the safety, efficacy and tolerability of CIN-103 in 450 adults with IBS-D


CINCINNATI – February 22, 2024 – CinPhloro Pharma, a CinRx portfolio company advancing CIN-103 as a new approach for the chronic treatment of irritable bowel syndrome with predominant diarrhea (IBS-D), today announced the first clinical trial participant has been dosed in its Phase 2 enviva study. CIN-103, a novel formulation of phloroglucinol intended for long-term use, is a non-opioid based small molecule designed to address multiple IBS-D action points including motility, secretion, pain, spasms and inflammation.

“IBS-D is a complex condition impacting the daily lives of more than 16 million people in the United States alone with no approved medicines for long-term treatment,” said Jon Isaacsohn, M.D., Founder and Chief Executive Officer at CinRx Pharma. “CIN-103 is an improved formulation and delivery of phloroglucinol, which is an approved product in select countries outside of the U.S. for the treatment of gastrointestinal disorders. The enhanced pharmacokinetic (PK) properties of CIN-103 combine immediate-release and delayed-release processes for a proprietary pulsatile delivery offering sustained drug exposures with less frequent dosing while maintaining efficacy over time.”

“CIN-103 has great potential to address an unmet medical need for IBS-D and provide physicians and patients with an improved therapeutic option for long-term management of this multifactorial condition,” said Darren Brenner, M.D., Professor of Gastroenterology Medicine & Surgery at Northwestern University’s Feinberg School of Medicine. “I am encouraged by early studies of CIN-103 demonstrating a superior PK profile and absence of anticholinergic side effects compared to other antispasmodics. Previous investigations of antispasmodics available in the U.S. suffer from outdated data and methodological limitations. Ongoing research involving CIN-103 holds promise for improving global symptoms in patients with IBS-D.”

About the enviva Study:

The Phase 2 enviva study (NCT06153420) is a randomized, double-blind, placebo-controlled study to evaluate the safety and efficacy of multiple dose strengths of CIN-103 in adults with IBS-D over 12 weeks of treatment. The study endpoints include patients’ clinical response relative to placebo on abdominal pain and stool consistency (as a composite responder). The trial aims to enroll 450 participants. More information can be found at

About CinPhloro Pharma:

CinPhloro Pharma, a CinRx portfolio company, is dedicated to developing the first safe, effective and long-term treatment option for irritable bowel syndrome with predominant diarrhea (IBS-D). CinPhloro’s CIN-103 is a novel formulation of phloroglucinol, a small molecule available in certain countries for symptomatic relief of functional GI disorders. CIN-103 was modified to address the shortcomings of phloroglucinol, including its short half-life, and to target multiple IBS-D action points, including motility, secretion, pain, spasms and inflammation. 


About CinRx Pharma:

CinRx Pharma is a biotech company advancing a diverse portfolio of high-impact medicines through clinical development with a unique hub-and-spoke business model. CinRx’s approach combines financing with the efficient progression of therapeutic candidates within its portfolio, each managed by CinRx’s central infrastructure and operating team. Current CinCos address areas of high unmet medical need including metabolic, gastrointestinal, and oncology. Differentiated by an asset selection process agnostic to therapeutic area, a strategic CRO partnership, and insights from thousands of development programs, CinRx identifies, funds and accelerates promising drugs with the potential to have the highest impact on patients’ quality of life. CinRx Pharma is headquartered in Cincinnati, Ohio.

For more information, please visit or follow the company on X and LinkedIn.


Media Contact:

Cassidy McClain

Account Director, Communications

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CinRx Pharma Contact:

Jason Westerheide

Executive Director, Business Development

[email protected]