GreenLight Wins $3.3M Grant to Pursue mRNA-based Gene Therapies

The Bill & Melinda Gates Foundation has awarded a $3.3 million grant to GreenLight Biosciences to develop gene therapies revolving around messenger RNA (mRNA) — the intermediate molecule between DNA and proteins — for sickle cell disease (SCD) and other global health challenges, according to a press release.

Scientists have sought to treat SCD through gene editing, which consists of correcting a defective gene by “overwriting” it with a healthy version, essentially editing its instructions for making a protein.

Disorders caused by a single gene — such as SCD, which is caused by mutations in the HBB gene — make ideal candidates for this approach. The HBB gene normally provides instructions for making a protein called beta-globin, a component of a larger protein called hemoglobin that carries oxygen to the body’s organs and tissue.

Preclinical studies have demonstrated the potential for gene editing in this context, although few candidate therapies have reached the clinical trial stage.

In SCD, gene editing approaches usually correct the faulty HBB gene, or introduce the fetal version of that gene, in hematopoietic stem cells — the stem cells that give rise to blood cells.

GreenLight, conversely, is developing gene-editing strategies that target mRNA. Rather than editing the gene within the cells’ DNA, this approach consists of delivering healthy copies of mRNA to the cells. The cells then can use these healthy copies as a template for generating a functional version of the protein.

This technology is already being used to develop vaccine candidates for infectious diseases, such as COVID-19.

Unlike in gene editing-based medicines, patients require long-term treatment with mRNA strategies. However, since gene-editing technologies can change the DNA sequence in unwanted regions, the mRNA approach also comes with fewer risks.

Although GreenLight will initially pursue potential SCD cures, the company plans to expand into other diseases affecting underserved populations. One such patient group is individuals living with HIV in developing countries.

“Funders are recognizing the potential of our innovative approach to gene editing that, in combination with our proprietary RNA manufacturing capability, has the potential to deliver accessible gene therapies and improve human health globally,” said Marta Ortega-Valle, GreenLight’s senior vice president of human health and corporate development.

Once the company moves a validated therapy into clinical use, it plans to use its proprietary biomanufacturing platform to mass-produce affordable treatments.

“Finding a safe and effective therapy is critical, but equally important is the ability to produce it affordably for broader access,” Ortega-Valle said.

“That capability does not yet exist in the market, but GreenLight’s end-to-end, self-contained manufacturing platform aims to make that possible for all mRNA-based therapies and vaccines,” she added.