Wednesday, April 19, 2023
SAB Biotherapeutics, a clinical-stage biopharmaceutical company with a novel immunotherapy platform that produces specifically targeted, high-potency, fully-human, multi-epitope binding immunoglobulin (hIgG, or fully human polyclonal) antibodies, without the need for human donors, announced today that the U.S. Food and Drug Administration (FDA) has granted Breakthrough Therapy Designation (BTD) to SAB-176, an investigational therapeutic, for post-exposure prophylaxis for Type A and Type B influenza illness in high-risk patients, including those who have anti-viral resistant strains. On April 13, SAB announced that the FDA had granted Fast Track designation to SAB-176, and that the company had also received FDA guidance and regulatory alignment on advancing SAB-176 into the next phase of development through initiation of a Phase 2b dose-range finding efficacy and safety trial in patient populations at high-risk for developing severe disease.
The FDA’s Breakthrough Therapy designation process is designed to expedite the development and review of a medicine that is intended to treat a serious or life-threatening condition and preliminary clinical evidence indicates that the drug may demonstrate substantial improvement over therapies currently available on a clinically significant endpoint(s). Products that qualify for Breakthrough Therapy designation receive more benefits than Fast Track products.
“Influenza continues to pose considerable health concerns both in the U.S. and on a global scale. This Breakthrough Therapy designation signifies an important step forward in our fight against this disease," said Eddie Sullivan, PhD, co-founder, President & CEO of SAB Biotherapeutics. "Even though both designations can be requested early in development, the requirements for Breakthrough Therapy designation are higher than those for the Fast Track program. For Breakthrough Therapy designation, the improvement demonstrated must be substantial. We are proud that based on generated preclinical and clinical evidence, SAB-176 has received both Breakthrough and Fast Track designations, a combination rarely seen. These designations further assure us that SAB-176 has a clear regulatory and clinical development path to progress this important therapeutic.”
SAB-176 is being developed for several influenza indications, including treatment of high-risk patient populations, as well as pre- and post-exposure prophylaxis. The FDA’s Breakthrough Therapy designation confirms that the multi-epitope targeting modality of SAB-176 has a clear differentiation vs. monoclonal antibodies (mAb) that bind to a single epitope, and SAB’s treatment can sustain its efficacy over viral mutations and prevent or reduce the risk of emerging treatment-resistant influenza strains. Virus evolution driven by vaccines or treatments is a serious challenge and the use of therapeutics can create “escape mutants” or versions of a virus that have changed to escape pressure on virus survival driven by an antiviral treatment, whether it is a small molecule or monoclonal antibody modality.
Clinical evidence for SAB-176 generated in the SAB-176-201 clinical trial showed a significantly shorter time to resolution of positive viral culture vs. the control group. SAB’s DiversitAb™ platform data also showed that the multi-epitope binding modality of SAB’s biologic treatments reduces risk for emergence of treatment-resistant viruses. Preclinical evidence of in vivo efficacy of SAB-176 in the treatment-resistant strains further supports the scientific foundation for this Breakthrough designation.
SAB-176 is a highly potent immunotherapy that is grounded in fundamentals of the natural immune response to neutralize Type A and Type B influenza viruses by generating endogenous multi-epitope binding antibodies. The treatment is produced using SAB's proprietary DiversitAb™ platform, which enables—for the first time—rapid, scalable production of highly potent, fully-human polyclonal IgG antibodies, without the need for human donors. The platform is capable of addressing the emergence and diversity of modern health challenges, including seasonal and pandemic influenza, COVID-19, Clostridioides difficile (CDI or C. diff), autoimmune disorders, such as type 1 diabetes, and cancers.
SAB-176 has undergone multiple clinical and pre-clinical studies, including a Phase 1 trial in healthy volunteers and a Phase 2a challenge study completed last year. The data indicate that SAB-176 offers broad antibody protection against multiple strains of this rapidly mutating virus. In the Phase 2a study, SAB-176 showed broad cross-protection across seasonal and pandemic strains of Influenza A and lineages of influenza B including strains that were not specifically targeted in the manufacturing of the therapeutic. At the same time, the FDA guidance and regulatory alignment received by the company paves the way for changing the strains that are specifically targeted by the product over time to potentially ensure that the product maintains efficacy as the virus mutates over time.
The DiversitAb™ platform is a first-of-its-kind technology capable of producing large amounts of fully-human high-titer, high-avidity multi-epitope binding antibodies across multiple targets without the need for human donors. SAB is leveraging its proprietary platform to discover and develop product candidates with the potential to be first-in-class or best-in-class against complex targets to treat or prevent diseases with significant unmet medical needs. These include infectious respiratory and gastroenterological diseases, immune and autoimmune disorders, and oncology.