Avobis Bio's Crohn Disease Cell Therapy AVB-114 Garners FDA RMAT Designation

Avobis Bio's AVB-114, an investigational implantable cell therapy product, has received regenerative medicine advanced therapy (RMAT) designation from the FDA for the treatment of Crohn disease perianal fistulas.¹

AVB-114 has previously been evaluated in the Mayo Clinic phase 1 STOMP-I clinical trial (NCT01915927) and is currently being evaluated by Avobis in the follow-on randomized, multicenter phase 2 STOMP-II clinical trial (NCT04847739).^1,2 Notably, in STOMP-I, at 12 months posttreatment, patients with persistent perianal Crohn disease showed 76% drainage cessation. Avobis also noted that the primary analysis for STOMP-II is complete and that data will be reported later this month by investigator David Schwartz,MD, a professor of medicine in the Division of Gastroenterology, Hepatology and Nutrition, and Department of Medicine, and the director of the Inflammatory Bowel Disease Center at Vanderbilt University Medical Center, at the American College of Gastroenterology's 2025 Annual Scientific Meeting, which is to be held October 24 to 29, 2025, in Phoenix, Arizona.

"We are encouraged by the FDA's affirmation that the STOMP clinical dataset demonstrates AVB-114's potential to meaningfully improve outcomes for Crohn disease patients with perianal fistulas – a serious condition lacking effective treatments," Tiffany Brown, PhD, the chief executive officer of Avobis Bio, said in a statement.¹ "Avobis looks forward to collaborating with FDA under RMAT designation to expedite a phase 3 trial and achieve our goal of reaching patients in need."

AVB-114, which is administered locally, consists of living cells and a plug-shaped bioabsorbable material and is intended to produce healing signals and generate tissue. It previously received fast track designation from the FDA in February of this year.²

“Perianal fistulas are a tremendous challenge for patients and their treating physicians,” William Faubion, Jr., MD, the dean of research at Mayo Clinic in Arizona, medical director of Mayo Clinic’s Center for Regenerative Biotherapeutics, and a gastroenterologist who specializes in inflammatory bowel diseases, said in a statement at the time.² “If the results of the ongoing phase 2 trial are consistent with the impact we saw in the phase 1 trial, this treatment could transform the lives of Crohn disease patients living with perianal fistulas.”

Avobis is not the only company currently developing a cell therapy approach to Crohn disease. Cellularity’s PDA-001, a placental-derived mesenchymal-like adherent stromal cell (MLASC) therapy, has been evaluated in a phase 2 clinical trial (NCT01155362) for adults with moderate-to-severe Crohn disease.³ The trial is completed and Cellularity is currently awaiting an end of phase 2 meeting with the FDA regarding the program.

CGTLive® has previously spoken to Adrian Kilcoyne, MD, MPH, MBA, the chief medical officer of Celularity, about the company's work on MLASC therapy for Crohn disease.⁴ He explained that Celularity previously carried out several phase 1 clinical trials evaluating a placental-derived MLASC approach to treating Crohn disease and that these legacy trials initially measured efficacy outcomes at early time points, such as 12 weeks or 3 months posttreatment.

“...I have said repeatedly that I don't believe the mesenchymal stem cell [MSC] studies have failed, I believe the study designs have failed the MSCs,” Kilcoyne told CGTLive. “I think now with our understanding of the mode of action, we can design the end points a lot better [and] we can design the time points a lot better so what we may have are longer studies, but with the appropriate end points.”

REFERENCES
1. FDA grants RMAT designation to Avobis Bio's implantable cell therapy AVB-114 for Crohn's perianal fistulas. News release. Avobis Bio LLC. October 3, 2025. Accessed October 8, 2025. https://www.prnewswire.com/news-releases/fda-grants-rmat-designation-to-avobis-bios-implantable-cell-therapy-avb-114-for-crohns-perianal-fistulas-302574412.html
2. FDA grants fast track designation for AVB-114. News release. Avobis Bio LLC. October 3, 2025. Accessed October 8, 2025. https://avobisbio.com/fda-grants-fast-track-designation-for-avb-114/
3. Allogeneic placental-derived product candidates. Cellularity. Website. Accessed October 8, 2025. https://celularity.com/pipeline/
4. Kilcoyne A, Koppisetti S, GloverB, et al. Placental-derived mesenchymal-like adherent stromal cell (MLASC) therapy results in alterations in gene and protein signatures associated with inflammation and fistula formation in patients with Crohn’s disease. Presented at: American Society of Gene and Cell Therapy (ASGCT) 2023 Annual Meeting. May 16-20, 2023; Los Angeles, CA. Abstract #1111