CSL Behring acquires Tucson biotech for $91 million

Biotherapeutics company CSL Behring in King of Prussia will buy Calimmune Inc. for at least $91 million to add an early-stage stem-cell gene therapy for sickle-cell disease to its product pipeline.

The Tucson-based biotechnology firm is working on a gene therapy and has two "platform" technologies to address challenges in the manufacturing and administration of gene- and stem-cell-based treatments, aligning with CSL Behring's expertise in hematology.

In addition to the $91 million, the agreement includes performance-based milestone payments of up to $325 million. The deal is expected to close within two weeks.

Calimmune, a private company, has about 40 employees and research and drug-development facilities in Pasadena, Calif., and Sydney, Australia.

Calimmune's "Select+" and "Cytegrity" technologies are "designed to address some of the major challenges currently associated with the commercialization of stem-cell therapy," according to CSL Behring. This includes the ability to manufacture consistent, high-quality products, and to improve engraftment, efficacy, and tolerability, the company said in a statement. "Both technologies have broad applications in ex-vivo stem-cell gene therapy."

This type of treatment involves genetically altering cells outside the body before transplanting them back into the patient.

Currently, patients with sickle-cell disease receive chemotherapy to knock out bad cells in bone marrow to make room for good, new cells, said CSL Behring spokeswoman Natalie de Vane. But patients can become very ill, and administering the treatment requires a hospital visit.

Calimmune's "Select+" technology would potentially allow lower doses of chemotherapy by reducing toxicity and improving efficacy of the gene therapy. The hope is that patients would not become as sick, and the procedure could be handled in a doctor's office instead of a hospital, she said.

CSL Behring, which employs about 700 in King of Prussia, makes products to treat bleeding disorders such as hemophilia and immune deficiency diseases.

CSL Behring is part of CSL Limited in Melbourne, Australia. CSL chief executive officer and managing partner Paul Perreault said: "Calimmune shares in our promise and focus to improve the lives of patients with rare and serious medical conditions. The acquisition represents another important step in the execution of our strategy for sustainable growth. Calimmune's scientific accomplishments are impressive."

While Calimmune is still in the early stages, "we believe that our combined strengths have tremendous potential to change treatment paradigms, and most importantly, significantly improve the lives of our patients," Perreault said.

Calimmune's chief executive officer, Louis Breton, said: "We are excited to become part of CSL Behring. They are an established global industry leader in protein-replacement therapies and have a proven track record. …  Together, we are well-positioned to take our achievements to the next level."