Who We Are
Visterra is a clinical-stage biopharmaceutical company focused on applying its novel Hierotope platform to identify unique disease targets and to design and engineer precision antibody-based biological medicines against such targets that are not adequately addressed with conventional approaches.

Our Business Focus
We believe that our platform enables us to address the significant unmet need for effective therapies to prevent and treat infectious diseases caused by organisms that have a high degree of diversity among strains, frequent mutations, and a high prevalence of treatment resistance. Our platform also enables us to design and engineer antibody-based biological product candidates that selectively modify the activity of endogenous targets that have limited surface area, are hard to access, have dynamic structures, and/or are similar to other proteins in the body that should be avoided. We believe our platform will enable the advancement of one product candidate each year to be ready for submission of an investigational new drug application.

Our initial focus is on the prevention and treatment of acute infectious diseases with limited or suboptimal treatment options. Our antibody-based biological product candidates have the potential to provide broad coverage across viral strains, including mutated strains and strains that have recently emerged. We believe that our acute infectious disease product candidates could be effective, as a single-dose administration, even when administered several days after onset of illness, and will be refractory to the emergence of resistance. We further believe that our infectious disease product candidates will have favorable safety profiles because they are directed against targets that are not normally found in human cells. Further, we expect that similar to most other development programs of product candidates targeting acute infectious diseases, our acute infectious disease development program will benefit from the availability of highly predictive animal models and reliable point-of-care and rapid diagnostics, and will include short-duration clinical trials with rapid efficacy read-out and a smaller number of required patients, compared to clinical development programs for chronic conditions.

In the case of non-infectious diseases, we believe our Hierotope platform enables the engineering of antibodies directed against specific targets, or epitopes, on endogenous targets that are difficult to address by traditional techniques.

Our Proprietary Hierotope® Platform
Our Hierotope platform enables us to design and engineer antibody-based biological product candidates, each of which binds to an epitope, which is a key component of a larger molecule known as an antigen. We are targeting these epitopes that are composed of highly networked amino acids and that we believe are important for the function of the antigen. We refer to these specific epitopes, which we believe are highly attractive targets, as Hierotopes. The term Hierotope is derived from “hiero,” the Greek term for sacred, and “tope,” the Greek term for site. In the case of infectious diseases, we believe these Hierotopes are critical to the structural and functional integrity of the pathogen, are common across all strains of the pathogen and resistant to mutation. In the case of endogenous targets, we believe that these Hierotopes are critical for the biological activity of the target.

We utilize our proprietary computational tools and technologies, the core of which is our atomic interaction network analysis, or AIN analysis, to both identify Hierotopes and design and engineer antibody-based biological medicines to target these Hierotopes. Using our Hierotope platform, we deploy our AIN analysis to characterize each amino acid in a protein in terms of its interactions with other amino acids, resulting in the identification of the most interconnected ones. Once we identify the Hierotope, we develop a new antibody scaffold or select an antibody scaffold from an existing antigen-antibody database that best matches the Hierotope we are targeting. Finally, starting with an antibody scaffold, we deploy our AIN analysis to design and engineer an optimized antibody-based drug candidate that selectively targets the identified Hierotope.

Traditional antibody engineering approaches focus on enhancing the strength of the interaction between the antibody and the antigen by altering the amino acids within the antibody, based on knowledge from antibody libraries generated via random mutations or crystal structure analysis. We believe our Hierotope platform can enable the identification of the specific sites on the antibody that we can alter to improve the antibody’s characteristics with respect to its interaction with the target antigen, without the limitations of conventional approaches. The use of our AIN analysis can supplement and extend the capabilities of conventional approaches for antibody engineering.

Our Pipeline
Our first two product candidates are intended to be effective as a single-dose intravenous administration for the treatment of infectious diseases. Our first and most advanced product candidate, VIS410, is a monoclonal antibody, or mAb, that we are developing for the treatment of hospitalized patients with influenza A, regardless of the viral strain. In our randomized, placebo-controlled Phase 2a clinical trial in healthy subjects inoculated with a pandemic strain of the influenza A virus, which we refer to as our Phase 2a Challenge Study, a single dose of VIS410 administered 24 hours after viral inoculation led to a statistically significant reduction in the amount of virus detected from the nasal secretions of treated subjects as compared to control subjects. We are conducting a global Phase 2a clinical trial in ambulatory patients diagnosed with influenza A, and we plan to initiate a global Phase 2b clinical trial in early 2018 in hospitalized patients diagnosed with influenza A who require oxygen support. We have been awarded a contract from the U.S. Biomedical Advanced Research and Development Authority, or BARDA, an agency of the U.S. government’s Department of Health and Human Services, that includes a forty-month base period with committed funding of $38.6 million for the development of VIS410 and options that, if exercised in full by BARDA, would extend the contract to sixty months and increase the total funding for the development of VIS410 to $214.0 million.

Our second infectious disease product candidate, VIS513, is a mAb for the treatment of Dengue. The development of VIS513 is being advanced through our strategic relationship with the Serum Institute of India Private Limited, or SIIPL, in select territories. Under our collaboration with SIIPL, we expect SIIPL will initiate Phase 1 clinical trials of VIS513 in 2018.

VIS649 is our first product candidate targeting an endogenous protein—i.e., a protein that is produced or synthesized within the body. VIS649 is a mAb targeting the protein A Proliferation-Inducing Ligand, or APRIL. We are developing VIS649 as a treatment for Immunoglobulin A nephropathy, or IgAN, a kidney disease for which currently there is no specifically approved therapy. We expect to initiate Phase 1 clinical trials of VIS649 in 2018.

Our product candidate, VIS705, is an antibody-drug conjugate, or ADC, for the treatment of Pseudomonas aeruginosa, a type of Gram-negative bacterial infection. We have engineered a mAb directed to the core carbohydrates, or glycans, on the Pseudomonas aeruginosa bacterium. In preclinical studies, our mAb bound strongly to all 35 Pseudomonas aeruginosa strains tested, covering all major serotypes, including multi-drug resistant clinical strains. The ADC containing our mAb has demonstrated in vivo activity against Pseudomonas aeruginosa in an acute lung infection mouse model.

Our early-stage infectious disease programs include VIS-FLX, a long-acting mAb for the prevention of influenza A in high-risk populations that do not generally develop an adequate protective immunity in response to influenza vaccines; VIS-RSV, a bispecific mAb for the treatment of respiratory syncytial virus, or RSV; and VIS-FNG, a bispecific mAb for the treatment of severe fungal infections caused by Candida, Aspergillus and Cryptococcus. Our early-stage programs that target endogenous proteins include VIS-SYN, a mAb targeting Syndecan-1, an important antigen found on various tumor types and recognized as a precursor to multiple myeloma, and VIS-NAV, a mAb for the treatment of certain chronic pain conditions, targeting the sodium ion channel NaV1.7, which has been shown to be a key regulator of activation of pain-sensing neurons.

Our Heritage
Our company was founded on the research into the fundamentals of epitope characterization by our scientific founder and member of our board of directors, Dr. Ram Sasisekharan, at the Massachusetts Institute of Technology, and we began developing our Hierotope platform as a result of the findings from his research.

Dr. Sasisekharan founded Momenta Pharmaceuticals, Inc., which focuses on the development and commercialization of complex drugs, and Cerulean Pharma Inc., a company focused on nanoparticle drugs for oncology.

As of 09/15/17

Visterra, Inc.  |  275 2nd Avenue  |  Waltham, MA 02451  |  617-498-1070  |  © 2018 Visterra, Inc. All Rights Reserved.