Gates Foundation Invests up to $50 Million in Tessera for In Vivo Gene Writing Therapy for SCD

Rare Daily Staff

The Bill and Melinda Gates Foundation agreed to invest up to $50 million in Tessera Therapeutics to jointly fund the company’s in vivo program for sickle cell disease to advance a gene writing therapy to the clinic.

Sickle cell disease (SCD) is an inherited blood disorder that affects the red blood cells, which are essential for carrying oxygen to all organs and tissues of the body. SCD causes severe pain, organ damage, and shortened life span due to misshapen or sickled blood cells. People with SCD can experience painful blood vessel blockages, also known as vaso-occlusive crises (VOCs), that can lead to acute chest syndrome, stroke, jaundice, and symptoms of heart failure. Individuals may also experience anemia, which can result in end-organ damage and premature death. VOCs are the hallmark of SCD, often resulting in severe and debilitating pain.

Though the condition is considered rare in the United States, there are millions of people worldwide living with SCD. SCD disproportionately affects populations in low- and middle-income countries.

Tessera is developing Gene Writers for sickle cell disease (SCD) designed to enable a correction of the sickle mutation to wild-type with one-time intravenous administration in vivo, without the need for complex stem cell mobilization or toxic chemotherapy conditioning. Critical in enabling in vivo therapies, Tessera is leveraging its proprietary non-viral delivery platform to develop lipid nanoparticles targeting delivery of Gene Writers to long-term hematopoietic stem cells.

Gene Writing is a proprietary way of genome engineering that aims to unlock broad new therapeutic frontiers. The platform is designed to write therapeutic messages into the genome by efficiently changing single or multiple DNA base pairs, precisely correcting insertions or deletions, or adding exon-length sequences and whole genes.

The company’s proprietary lipid nanoparticle delivery platform is designed to enable the in vivo delivery of RNA to targeted cell types. The company said it believes the technology will not only be able to only cure diseases that arise from errors in a single gene, but also modify inherited risk factors for common diseases and create engineered cells to treat cancer and potentially autoimmune and other diseases.

“Sickle cell disease patients globally remain deeply underserved by existing treatment options. We are excited to develop what we believe will be a disruptive one-time curative treatment for SCD that is safer, easier, and more scalable than ex vivo genetic approaches,” said Michael Severino, CEO of Tessera Therapeutics. “We look forward to advancing a genetic medicine that can potentially reshape the treatment landscape for sickle cell disease worldwide.”

Photo: Michael Severino, CEO of Tessera Therapeutics