Artax Biopharma (Cambridge, MA), has successfully solved the crystal structure of its target protein by using X-ray diffraction at the XALOC beamline of the ALBA Synchrotron.

Artax, which has recently closed a series B round of financing led by Advent life science (UK) and former Genzyme CEO Henry Termeer, is developing a new generation of oral compounds against autoimmune diseases.

Autoimmune diseases cause the immune system to function abnormally, attacking body tissues and organs that it considers “foreign”. Current treatments have two big pitfalls: their administration is mostly by intravenous route, they have low specificity and exert an immunosuppressant action. Hence, currently available treatments severely interfere with the immune system, decreasing their activity, which in turn reduces their effectiveness against infections by viruses and bacteria.

Instead, Artax compounds prevent T lymphocytes from responding against antigens but preserves their protective role against infection by pathogens. Such modulatory control of T cells allows the development of new treatments for a wide range of inflammatory and autoimmune diseases. Phase 1a and phase 1b have been completed with Artax most advanced compound and phase 2a will soon be initiated. The company also allocates part of its funds to develop a portfolio of new molecules.

A strategically important part of this effort is dedicated to a collaboration started in 2015 with the ALBA Synchrotron, in particular with the team of the Macromolecular Crystallography beamline XALOC. Different constructs of the Artax target protein, produced at the Biomolecular Screening & Protein Technologies Unit (CRG, Barcelona) directed by Carlo Carolis, were tested against several hundreds of crystallization conditions by ALBA personnel. The best crystals were diffracted with X-rays. In a few months, Fernando Gil and Roeland Boer, from the XALOC team, helped Artax to resolve the first ever structure of its target protein.

Fig. Crystals obtained in crystallization plates by using the vapour diffusion

method in sitting drops. © Artax Biopharma

The success of the collaboration was due to the close and iterative interaction between the three parties, Artax, CRG and ALBA. Artax acknowledged the outstanding scientific level and commitment of ALBA scientists and the valuable help of the industrial liaison office. Crystals grown in ALBA diffracted to a resolution better than 2 Å, which will accelerate the identification of new candidates and support Artax discovery efforts.