Publication Authored by Researchers at Selecta Biosciences and the National Cancer Institute in Proceedings of the National Academy of Sciences (PNAS) Discusses Restoration of Anti-Tumor Activity of Recombinant Immunotoxin LMB-100 When Combined with SVP-R

Selecta’s Immune Tolerance SVP Platform Also Discussed in Scientific American’s January 2018 Issue

WATERTOWN, Mass., Jan. 09, 2018 -- Selecta Biosciences, Inc. (Nasdaq:SELB), a clinical-stage biopharmaceutical company focused on unlocking the full potential of biologic therapies by avoiding unwanted immune responses, today announced that Proceedings of the National Academies of Sciences (PNAS) has published a paper co-authored by the company with researchers from the National Cancer Institute (NCI), part of the National Institutes of Health. The paper, entitled “Tolerogenic nanoparticles restore the anti-tumor activity of recombinant immunotoxins by mitigating immunogenicity,” focuses on work conducted by Selecta and Dr. Ira Pastan’s lab at NCI. Dr. Pastan is Senior Investigator, Head, Molecular Biology Section, at NCI’s Center for Cancer Research and a Fellow of the National Academy of Sciences.

“The efficacy of protein-based drugs, including promising immunotoxins such as LMB-100, can be limited by the formation of anti-drug antibodies (ADAs),” stated Takashi Kei Kishimoto, Ph.D., Chief Scientific Officer of Selecta and a co-author of the publication. “Led by researchers at NCI, this preclinical work highlighted the ability of SVP-Rapamycin to mitigate immunogenicity to LMB-100, which is a critical step toward delivering on the full potential of this very promising class of drugs in the field of oncology. We look forward to working with NCI researchers to bring this combination therapy, known as SEL-403, into the clinic later this quarter.”

Selecta’s SEL-403 product candidate consists of SVP-Rapamycin in combination with LMB-100. SVP-Rapamycin is Selecta’s proprietary, clinical-stage anti-drug antibody (ADA) prevention and immune tolerance technology. LMB-100 was in-licensed by Selecta from NCI. It is a recombinant immunotoxin that targets mesothelin, a protein expressed in nearly all mesotheliomas, pancreatic adenocarcinomas and a high percentage of other malignancies, including lung, breast and ovarian cancers. Last week, Selecta Biosciences announced that an investigational new drug application has been accepted by the U.S. Food and Drug Administration for SVP-Rapamycin in combination with LMB-100 for the treatment of mesothelioma patients. 

In the PNAS publication, the authors described preclinical work in which SVP-Rapamycin mitigated the formation of inhibitory ADAs to LMB-100 in both naïve mice and mice pre-exposed to LMB-100, resulting in restoration of LMB-100’s anti-tumor activity. The authors note that this strategy for mitigating immunogenicity is indicative of a novel approach to unlock the full potential of recombinant immunotoxin therapy for solid tumors and that the results may have implications for other highly foreign, lifesaving therapeutic proteins. An abstract of this publication can be accessed at http://www.pnas.org/content/early/2018/01/03/1717063115.abstract.

Additionally, Selecta’s SVP-Rapamycin platform is discussed in the January 2018 edition of Scientific American. The article, entitled “Medicine War Against Ourselves,” can be accessed via Selecta’s homepage at http://selectabio.com.

About Selecta Biosciences, Inc.
Selecta Biosciences, Inc. is a clinical-stage biopharmaceutical company that is focused on unlocking the full potential of biologic therapies by avoiding unwanted immune responses. Selecta plans to combine its tolerogenic Synthetic Vaccine Particles (SVP™) to a range of biologics for rare and serious diseases that require new treatment options. The company’s current proprietary pipeline includes SVP-enabled enzyme, oncology and gene therapies. SEL-212, the company’s lead candidate in Phase 2, is being developed to treat severe gout patients and resolve their debilitating symptoms, including flares and gouty arthritis. An investigational new drug (IND) application was recently accepted by the U.S. Food and Drug Administration (FDA) for a combination therapy consisting of SVP-Rapamycin and LMB-100 (Selecta’s SEL-403 product candidate) for the treatment of patients with malignant pleural or peritoneal mesothelioma. Selecta’s two proprietary gene therapy product candidates, SEL-302 and SEL-313, are being developed for rare inborn errors of metabolism and have the potential to enable repeat administration. The use of SVP is also being explored in the development of vaccines and treatments for allergies and autoimmune diseases. Selecta is based in Watertown, Massachusetts. For more information, please visit http://selectabio.com and follow @SelectaBio on Twitter.

Forward-Looking Statements
Any statements in this press release about the future expectations, plans and prospects of Selecta Biosciences, Inc. (“the company”), including without limitation, statements regarding the company’s initiation of a Phase 1 trial for SEL-403 with NCI in Q1 2018, whether SEL-403 has the potential to mitigate immunogenicity, whether Selecta’s SVP platform might be effective in combination with other highly foreign, lifesaving therapeutic proteins, the potential of SEL-212 to treat severe gout patients and resolve their debilitating symptoms, the company’s ability to unlock the full potential of biologic therapies, the potential applications for products utilizing the SVP platform in areas such as enzyme therapy, gene therapy, oncology therapy, vaccines and treatments for allergies and autoimmune diseases, the potential of the company’s two gene therapy product candidates to enable repeat administration and other statements containing the words “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “hypothesize,” “intend,” “may,” “plan,” “potential,” “predict,” “project,” “should,” “target,” “would,” and similar expressions, constitute forward-looking statements within the meaning of The Private Securities Litigation Reform Act of 1995. Actual results may differ materially from those indicated by such forward-looking statements as a result of various important factors, including, but not limited to, the following: the uncertainties inherent in the initiation, completion and cost of clinical trials including their uncertain outcomes, the unproven approach of the company’s SVP technology, and other important factors discussed in the “Risk Factors” section of the company’s Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission, or SEC, on November 7, 2017, and in other filings that the company makes with the SEC. In addition, any forward-looking statements included in this press release represent the company’s views only as of the date of its publication and should not be relied upon as representing its views as of any subsequent date. The company specifically disclaims any obligation to update any forward-looking statements included in this press release.

Contact Information:
Jason Fredette
Selecta Biosciences, Inc.
617-231-8078
[email protected]