$545 Million, exclusive global license agreement affirms Pfizer’s long-term commitment to gene therapy development.

In exchange for long-term global commercialization rights for Sangamo Therapeutics’ lead gene therapy candidate and orphan drug SB-525, which it is developing as a one-time treatment for hemophilia A, Pfizer will pay the California-based company $70 million upfront and up to $475 million in milestone payments, including up to $300 million for the development and commercialization of SB-525 and up to $175 million for the development of additional hemophilia A gene therapy product candidates. The agreement also includes tiered double-digit royalties on any net sales.

Hemophilia A is approximately four times as common as hemophilia B and is an inherited disease that results from a lack of the clotting factor VIII. According to the National Hemophilia Foundation, approximately 20,000 Americans have the two diseases. Gene therapy is considered a good option because both disorders are due to a deficiency in a specific clotting factor, which potentially can be corrected by inserting the relevant genes.

With SB-225, a recombinant adeno-associated virus (rAAV) vector is used to carry a functional copy of the factor VIII gene into the patient’s liver cells. It is hoped these inserted gene fragments will lead to long-term, increased production of the relevant clotting factor.

A clinical trial with SB-525 is anticipated to begin before the end of the second quarter of 2017 and will be conducted by Sangamo. If results are positive, Pfizer will take over any further research, development, manufacturing and commercialization activities for SB-525 and any additional products (SB-225 is one of four lead candidates for Sangamo). Sangamo will work with Pfizer on projects aspects related to viral delivery vectors.

Pfizer’s deal with Sangamo is only its latest. In 2014, the company signed a similar agreement with Spark Therapeutics surrounding SPK-9001, a gene therapy treatment for hemophilia B that is under investigation in a Phase I/II trial.

“Pfizer has made significant investments in gene therapy over the last few years and we are building an industry-leading expertise in rAAV vector design and manufacturing, said Mikael Dolsten, President of Worldwide Research and Development at Pfizer.

Sangamo believes that Pfizer is an “ideal partner” given its “long-standing heritage in rare disease, including hemophilia,” according to Sangamo's CEO Sandy Macrae. “We believe Pfizer's end-to-end gene therapy capabilities will enable comprehensive development and commercialization of SB-525, which could potentially benefit hemophilia A patients around the world. This collaboration also marks an important milestone for Sangamo as we continue to make progress in the translation of our ground-breaking research into new genomic therapies to treat serious, genetically tractable diseases," he said. Following announcement of the collaboration, the price of Sangamo shares rose nearly 45%.