Sirnaomics Testing STP144G Therapy With Eye Toward Human Trials Next Year

GalAhead platform driving therapies for aHUS, other complement system diseases

Marisa Wexler, MS avatar

by Marisa Wexler, MS |

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Sirnaomics developing complement therapies | aHUS News | illustration of scientist working in lab

Sirnaomics has launched preclinical testing of a first candidate therapy developed with its GalAhead platform for complement-mediated diseases, including atypical hemolytic uremic syndrome (aHUS).

The therapy, STP144G, is one of four experimental treatments developed with the proprietary Sirnaomics platform. Data from these early studies are expected to eventually support applications requesting authorization to start testing the therapy in human trials.

“We are seeing a quick expansion of our product pipeline developed with the GalAhead platform,” Patrick Lu, founder, board chairman, executive director, president, and CEO of Sirnaomics, said in a company press release.

“We expect … the first drug candidate based on this delivery platform to be in clinical study in the second half of 2023,” Lu said.

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The complement system is a group of immune proteins that are normally present in the blood and other bodily fluids in an inactive state.

In response to certain inflammatory stimuli (e.g., an infecting bacteria), the complement system becomes activated to drive a potent inflammatory reaction. This activation occurs in a step-by-step process, sort of like a series of dominoes falling, in which one complement protein activates another, which in turn activates others, and so on.

Sirnaomics’ GalAhead platform uses specially designed RNA molecules called mxRNA (miniaturized RNA interference triggers) to reduce the levels of specific target proteins.

When a protein is made inside a cell, the genetic code providing instructions for making the protein is copied from the gene’s DNA sequence into a temporary molecule called messenger RNA (mRNA). The mRNA carries the code to the cell’s protein-making machinery. mxRNA are small molecules designed to bind to the mRNA of specific target genes, interfering with this process and ultimately reducing the production of the target protein.

“We are highly satisfied with the performance of our proprietary GalAhead platform, which allows us to quickly, reproducibly, and predictably expand and progress our therapeutic pipeline based on this novel technology,” said Dmitry Samarsky, PhD, chief technology officer at Sirnaomics.

STP144G is a mxRNA-based therapy designed to reduce the levels of the complement factor B protein. Sirnaomics is now conducting studies that aim to support an investigational new drug application (IND), which is a formal request companies make to ask regulators for permission to begin testing experimental treatments in humans.

Three other investigational medications developed using the GalAhead platform are also moving into the candidate nomination stage. Two of these, STP146G and STP145G, are mxRNA therapies designed to lower the levels of the complement proteins C3 and C5, respectively.

The third, STP247G, is a muRNA (multi-unit RNA interference triggers) that is designed to simultaneously target complement factor B and C5. Unlike mxRNAs, which target single mRNAs and are made up of a single RNA sequence, muRNAs are designed to silence two or more targets simultaneously and are a combination of multiple RNA molecules.