Santa Ana launches $168M initiative for immunology research

Santa Ana Bio, inspired by the precision medicine movement in oncology, is pioneering a new approach in immunology by leveraging cell biology techniques. The biotech company, which emerged from stealth mode recently, secured $168 million in combined Series A and B funding to advance three core programs—a monoclonal antibody (mAb), a bispecific antibody, and an antibody-drug conjugate (ADC)—into clinical trials.

Founded by Versant Ventures and led by Peter Emtage, Santa Ana Bio is focusing on precision immunology. Emtage brings a wealth of experience from his tenure at Gilead Sciences' Kite Pharma unit and Cell Design Labs. His vision is to address immunological diseases by targeting specific cell types rather than merely blocking cytokines, which are not the root cause of many diseases. According to Emtage, cytokines are merely the messengers of disease, and the real issue lies in the cell types driving these biological processes. He believes that addressing these cell types directly could offer a more comprehensive resolution to diseases.

When Emtage presented his concept to Versant Ventures, the firm was intrigued. Jerel Davis, managing director at Versant Ventures and chair of Santa Ana’s board, recognized the potential of applying precision medicine to immunology, particularly given the current breakthroughs in the field. This enthusiasm and the promise of the technology led to Santa Ana’s launch in 2022, with significant investment from Versant, TPG Capital, and Google Ventures, among others.

The rapid succession of funding rounds, with a $125-million Series B led by Google Ventures, reflects the investors' confidence in Santa Ana’s three leading programs. This funding strategy was driven by the need to advance all three compounds simultaneously rather than sequentially. Davis noted that each program was compelling enough to warrant simultaneous development, necessitating the capital raised.

The funding will support Santa Ana into early 2027 and will enable the completion of two Phase I clinical trials. Additionally, the company is in discussions with several pharmaceutical firms for potential partnerships. Santa Ana is also developing a multi-omic platform to identify new targets by studying the progression of immunologic diseases. This effort is bolstered by a collaboration with Stanford University, which provides access to patient-derived tissues at various disease stages.

Santa Ana’s lead candidate, SAB01, is a bispecific antibody designed to conditionally inhibit c-Kit in the presence of a specific anchor target, thereby restricting its activity to mast cells. Emtage identified c-Kit as a key initiator of various diseases, including dermatological conditions, allergies, asthma, and pain. By targeting only the problematic mast cells, the bispecific antibody aims to be highly selective and effective. A Phase I trial for SAB01 in chronic inducible urticaria is scheduled to begin next year.

The second program, SAB03, is a PD-1-agonizing monoclonal antibody intended to eliminate pathogenic T-cells. Emtage explained that this approach targets the T-cells themselves rather than their byproducts like TNFα. This could potentially reduce inflammation and lead to disease resolution. Phase I trials for SAB03 are expected to start next year.

The third program, SAB05, is an antibody-drug conjugate designed to deliver glucocorticoid, a standard steroid for treating inflammatory diseases, in a targeted manner. By focusing on a central node of the immune system, the aim is to minimize the long-term toxicity usually associated with glucocorticoid treatment.

Overall, Santa Ana Bio is poised to make significant strides in the field of immunology by applying precision medicine techniques to target the cellular drivers of disease. With robust funding and a compelling pipeline, the company aims to bring new, effective treatments for various inflammatory conditions to the clinic.