- David Davidson, a longtime top executive at gene therapy developer Bluebird bio, will join the richly funded biotech startup Tessera Therapeutics as its chief medical and development officer, the latter company announced Wednesday.
- At Tessera, Davidson will be joined by former Spark Therapeutics and Moderna executive Hari Pujar, who will become chief operating officer, and by Lin Guey, most recently a vice president at Xilio Therapeutics who has been appointed head of rare disease strategy and operations.
- Launched by Flagship Pioneering last year, Tessera in January raised $230 million to advance its development of a new, more flexible type of genetic medicine, which the company and its venture backer have dubbed "gene writing."
Over nearly a decade at Bluebird, Davidson oversaw the development of gene replacement therapies for sickle cell disease, beta thalassemia and a rare metabolic disorder called cerebral adrenoleukodystrophy, as well as cell-based treatments for cancer. One of those therapies, dubbed Zynteglo, is approved in Europe for beta thalassemia.
By joining Tessera, Davidson is jumping back to the beginning, joining a preclinical biotech several years into a particularly ambitious quest to find a "better solution than CRISPR" for editing genes.
While much of the specifics have yet to be spelled out, Tessera's founders envision using so-called mobile genetic elements to make changes to DNA as small as an individual nucleotide and as large as an entire gene or specific coding region. The vision has its roots in the work of the late geneticist Barbara McClintock and her Nobel Prize-winning research into "jumping genes," or transposons.
Rather than use enzymes to make cuts in DNA, a la CRISPR, or viruses to deliver functional gene copies, such as approved treatments like Luxturna and Zolgensma, the Tessera team aims to insert into cells either RNA or DNA templates for mobile genetic elements they've identified in nature or engineered synthetically.
"The field has advanced so rapidly over the last decade," said Davidson."Having been immersed, I have a good sense of what the gaps are, what the limitations of the current technology are."
Davidson and his new executive colleagues will help shepherd Tessera's research forward, although Davidson would not give any indication of how far off clinical testing might be. The startup will have a sizable cash pile to draw on, however, having recently raised nearly a quarter of a billion dollars from an international group of investors that included the Alaska Permanent Fund Corporation, the SoftBank Vision Fund 2 and the Qatar Investment Authority.
Davidson's departure from Bluebird was notable, both because of the length of his tenure and because of the eventful past few months at the biotech company.
In January, Bluebird announced it would split itself into two companies, one focused on severe genetic diseases and the other cancer. The plan, Davidson said, was a "natural inflection point" for him to move on.
But the announcement of his planned exit, which will take effect April 16, happened to come soon after Bluebird reported two cancer cases in studies of its gene therapy for sickle cell disease. The company's investigation has since found the treatment "very unlikely" to have caused one of the cases, and has indicated the second may not actually meet the criteria for a diagnosis.
"My decision to depart Bluebird predated the safety signal emerging," said Davidson. "It really was triggered by the decision to split the company."
Per an agreement with Bluebird, Davidson will consult with the company for six months as it completes its review of the safety events.