Investigational Probiotic Drug Gains FDA Support for Phase 2 Obesity Trial

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The US FDA provided positive preliminary feedback on Northstrive Biosciences’ Investigational New Drug (IND) application for the company’s obesity treatment candidate, EL-22. The feedback supports the company’s plans to move forward with a phase 2 trial to evaluate EL-22 in combination with GLP-1 receptor agonists for obesity treatment.

The feedback followed a type B pre-IND meeting with the FDA, in which Northstrive discussed its nonclinical studies and clinical development plans for EL-22, according to an April 24, 2025, press release. The FDA’s responses confirmed that the company’s pharmacology studies provide sufficient evidence of EL-22’s activity, and that its nonclinical data supports the safety and efficacy of EL-22 in human populations with obesity. Additionally, the FDA agreed that previous phase 1 study data was adequate to initiate a phase 2 clinical trial.

"This positive reinforcement from the FDA is a critical milestone in the development of EL-22 to address one of obesity’s biggest unmet needs; the preservation of muscle for patients on GLP-1 therapies."

Northstrive has indicated that the FDA’s responses are sufficient to forego the pre-IND meeting and proceed directly with the filing of the IND application, which the company plans to submit in 2025. Following IND approval, the company aims to begin the phase 2 trial.

EL-22 is a novel, patent-pending engineered probiotic designed to express myostatin on its surface. This approach targets the myostatin pathway, which is critical to preserving muscle health during weight loss treatments, including GLP-1 receptor agonists. The company believes that EL-22’s potential to maintain muscle mass while promoting weight loss could address a key unmet need in the treatment of obesity.

Preclinical studies, including research published in 2022 using mdx mice— a model for Duchenne muscular dystrophy—demonstrated significant physiological and functional improvements with EL-22. Furthermore, the probiotic has completed a phase 1 clinical trial in South Korea, where it was shown to be generally well-tolerated and safe in healthy volunteers.

Deniel Mero, co-founder of Northstrive Biosciences, expressed optimism about the FDA’s feedback. “The nonclinical data package of EL-22, as well as the Phase 1 study conducted in South Korea, appear adequate to support the safety and activity in an obese patient population,” Mero stated. “This positive reinforcement from the FDA is a critical milestone in the development of EL-22 to address one of obesity’s biggest unmet needs; the preservation of muscle for patients on GLP-1 therapies.”

Northstrive is currently in discussions with Current Good Manufacturing Practices (cGMP) manufacturing partners to prepare for the production of EL-22 in anticipation of clinical trials.

Reference: Northstrive Biosciences Announces Positive FDA Response Supporting A Submission of IND for a Phase 2 Clinical Trial for EL-22 in Combination with GLP-1 Receptor Agonist for Obesity Treatment. News release. Northstrive Biosciences. April 24, 2025. Accessed April 24, 2025. https://www.biospace.com/press-releases/northstrive-biosciences-announces-positive-fda-response-supporting-a-submission-of-ind-for-a-phase-2-clinical-trial-for-el-22-in-combination-with-glp-1-receptor-agonist-for-obesity-treatment