Synlogic publishes papers in Nature journals demonstrating proof-of-mechanism and potential of synth

- Data show dose-responsive, non-saturated increases in gastrointestinal consumption of Phe in humans by SYNB1618 -

- SYNB1618 Phase 2 study in patients with PKU ongoing with proof-of-concept readout anticipated in 2H 2021 -

- Phase 1 study of SYNB1934, an evolved strain of SYNB1618 in the PKU portfolio, initiated -

CAMBRIDGE, Mass., July 22, 2021 /PRNewswire/ -- Synlogic, Inc. (Nasdaq: SYBX), a clinical stage company bringing the transformative potential of synthetic biology to medicine, announced today the publication of two papers in the journals Nature Metabolism and Communications Biology. The publications detail findings from a first-in-human study of investigational Synthetic Bioticâ„¢ medicine SYNB1618 and the development of a mechanistic model to predict the function of an engineered bacterial therapeutic in healthy volunteers and Phenylketonuria (PKU) patients. These data add to the growing body of scientific research demonstrating the therapeutic potential of Synthetic Bioticâ„¢ medicines for the treatment of PKU.

"Our orally administered Synthetic Biotic medicines are intended to address the needs of PKU patients of all ages and disease types through the consumption of phenylalanine (Phe) in the gastrointestinal tract. With two Phe-consuming strains now in the clinic, and a proof-of-concept readout in SYNB1618 anticipated in the second half of 2021, we look forward to advancing our PKU pipeline and developing a meaningful treatment for those living with PKU," said Aoife Brennan, M.B. Ch.B., Synlogic's President and Chief Executive Officer.

Key findings from the Nature Metabolism paper entitled, "Safety and pharmacodynamics of an engineered E. coli Nissle for the treatment of phenylketonuria: a first-in-human Phase 1/2a study":

In this first-in-human study of a frozen liquid formulation of SYNB1618 in healthy volunteers and patients with PKU, SYNB1618 was safe and well tolerated, with no systemic toxicity and no evidence of colonization. SYNB1618 was cleared within four days of the last dose.

Dose-responsive increases in strain-specific Phe metabolites in plasma and urine were observed, demonstrating SYNB1618 is able to consume Phe and convert it to non-toxic metabolites in the GI tract of both healthy volunteers and patients with PKU.

These data demonstrate the potential to use engineered bacteria in the treatment of rare metabolic disorders through the consumption of toxic substances in the GI tract.

Concurrently, the development of a mechanistic model predicting the potential for Phe-lowering efficacy in PKU patients was published today in Communications Biology. The paper, entitled, "Development of a Mechanistic Model to Predict Synthetic Biotic Activity in Healthy Volunteers and Patients with Phenylketonuria," used findings from the Phase 1/2a study to inform a mechanistic model of strain activity in PKU patients.

Key findings include:

Construction of a mechanistic model that predicts SYNB1618 function in non-human primates and healthy subjects is feasible by combining in vitro simulations and prior knowledge of human physiology.

The model can be extended using plasma Phe kinetics to PKU patients, informing clinical development of potential treatments for PKU.

Increases in Phe removal from the GI tract are predicted to correlate strongly with reduction of Phe in the blood.

The results of this dose-response model suggest Phe-consuming Synthetic Biotic medicines such as SYNB1618 may have potential to achieve clinically meaningful reduction of blood phenylalanine levels in patients with PKU.

Data on the solid oral formulation of SYNB1618 was presented at the American College of Medical Genetics meeting in April 2021. Data on the development of SYNB1934, an evolved strain of SYNB1618, was presented at the Synthetic Biology: Engineering, Evolution & Design (SEED) conference in June 2021.

SYNB1618 continues to advance in a proof-of-concept Phase 2 clinical trial in adults with PKU, SynPheny-1 study (NCT04534842), with data expected in the second half of 2021. Learn more by visiting Information about Synlogic's programs and pipeline can be found at

MacDougall Biomedical Communications, Inc.