Selecta Biosciences, Inc.

Good morning, and welcome to the Selecta Biosciences first quarter 2021 financial results and corporate update conference call. Currently, all participants are in a listen-only mode. This call is being webcast live on the investors and media section of Selecta's website at www.selectabio.com, and it is being recorded. For opening remarks, I would like to introduce Brad Doms, Chief Financial Officer of Selecta. Please go ahead.

Thank you, Operator, and good morning. Welcome to our first quarter 2021 financial results and corporate update conference call. The press release reporting our financial results is available on the investors and media section of our website, www.selectabio.com. and our quarterly report on Form 10-Q ended March 31st, 2021, which was filed today with the SEC. Joining me today are Carson Bruhn, our President and Chief Executive Officer, Dr. Peter G. Traver, our Chief Medical Officer, and Kei Kishimoto, our Chief Scientific Officer. During today's call, we will be making certain forward-looking statements, including without limitation statements about the potential safety, efficacy, and regulatory and clinical progress of our product candidates financial projections, and our future expectations, plans, partnerships, and prospects. These statements are subject to various risks that are described in our filings made with the SEC, including our most recent quarterly report on Form 10Q. Your caution not to place undue reliance on these forward-looking statements would speak only as of today, May 13th, 2021, and selected disclaims any obligation to update such statements, even if management's views change. I would now like to turn the call over to Carson Bruhn, our president and CEO. Carson.

Thank you, Brad. Good morning. I appreciate you joining us today. The outset of 2021 was marked with several strategic and financial milestones, as well as substantial pipeline progress, particularly in our gene therapy business. They continue to advance our clinically validated into a platform across enzyme therapies, gene therapies, and autoimmune diseases. I'll start with our enzyme therapies programs. Our SAL212 program, which was licensed to SOBI, is comprised of IMTOR, co-administers with our proprietary UR case, Pegafocase. We've continued to make progress in getting SAL212 approved to treat patients with chronic refractory gout, which is a significant unmet need. As a reminder, our dissolved clinical program kicked off in the third quarter of 2020 and consists of two double-blinded placebo-controlled trials of SAL212. In September, the first patient in DISAWP1 was dosed. DISAWP2 was initiated in December 2020. In both trials, SEL212 will be evaluated at two doses of Intor, 0.1 milligrams per kilogram, and 0.15 milligrams per kilogram, and one dose of Pagetri case, 0.2 milligrams per kilogram. Each trial aims to enroll 105 patients with 35 at each dose and 35 on placebo. Both trials have a six-month primary endpoint of serum uric acid levels below six milligrams per deciliter at the six-month time point, and only dissolve one will have a six-month extension for safety. Secondary endpoints include gout flare incidents, tender and swollen joint counts, and TOFUS burden, patient-reported outcome of activity limitation, and quality of life. We're pleased with the pace of enrollment, which is progressing on schedule, as we have put into place several procedures to proactively minimize the potential impact of the ongoing COVID pandemic. Top line data from the DISSOLVE program are expected in the second half of 2022. We intend to leverage the success of SEL212 and file an investigation new drug or ID application for a second enzyme program indication that combines mTOR with an IgA protease by the end of 2021. IgA nephropathy is a kidney disease that occurs when immune complexes of an antibody called immunoglobulin A1 accumulate in the kidneys. Genetic or environmental factors that cause this abnormal IgA1 and its accumulation in the kidneys can result in the development of IgA nephropathy, one of the most common causes of kidney disease. There are currently no approved therapies. However, with our novel combination therapy, we intend to treat the root cause of the disease and overcome previous limitations associated with IgA protease development. Now turning to our gene therapy programs. In collaboration with AskBio, we initiated the first in-human phase one dose escalation trial of SEL399, an AV8 empty vector capsid containing no DNA combined within TOR in February. The trial has been conducted in healthy volunteers and aims to determine the optimal dose of mTOR to mitigate the formation of antibodies to aviate capsid use in gene therapies. We are pleased with the progress made to date. We remain on track, and together with ASPbio, expect to report top-line data in the fourth quarter of 2021. Moving to an update for our gene therapy candidate, MMA101, and mTOR for the treatment of methylmalonic acidemia, or MMA, a rare monogenic disorder in which the body cannot break down certain proteins and fats. We recently strengthened our wholly-owned gene therapy portfolio by obtaining exclusive rights to the MMA 101 program. Aspire's decision to give all rights to Selecta is based on an internal strategic review and portfolio prioritization exercise conducted by Bayer, which acquired Aspire in 2020. We're grateful to the AskBio team for their partnership in progressing MMA101 through IMD-enabling studies and look forward to independently advancing the program to clinical development. Due to a third-party gene therapy-related manufacturing delay, we expect to file an IMD in the fourth quarter of 2021 for MMA101 in combination with mTOR. mTOR manufacturing continues to proceed smoothly, and there is no impact to any of Selecta's mTOR programs. The Phase I-II MMA 101 program, which is expected to commence in 2022, will explore biomarkers of the disease utilizing the antibodies and will evaluate safety and tolerability. The advancement of our gene therapy programs into the clinic builds on extensive preclinical data that we have demonstrated the potential benefits of the intraplatform in AAV gene therapy and prevent production of AAV-specific utilizing antibodies in vivo. In a recent preclinical study in non-human primates, Selector observed that co-administration of AV vector and mTOR enables higher and more durable transgenic expression, as well as robust inhibition of neutralizing antibodies. Earlier this week, we presented these findings at the annual meeting of the American Society of Gene and Cell Therapy, further demonstrating the potential of Selector's mTOR platform to mitigate AV immunogenicity and enable redosing of gene therapy treatments for various genetic disorders. Looking ahead, our proprietary gene therapy product candidate, SEL313, is being developed to treat onazine transcarbamylase, or OTC deficiency. OTC deficiency is an X-linked genetic disorder caused by genetic mutation in the OTC gene, which is critical for proper function of the urea cycle. We expect to file a clinical trial application, or CTA, and or an IND in 2022. We will also provide updates on our pediatric investigation plan for PIP for cell 313, which was submitted to the European Medicines Agency Pediatric Committee in February 2021. Before we wrap up on gene therapy, Sarepta Therapeutics continues to conduct preclinical work looking at the combination of mTOR in certain neuromuscular disorders, including Dijon muscular dystrophy, or DMD, and limb girdle muscular dystrophies, or LGMD subtypes. We recently received a 3 million milestone payment related to the completion of a preclinical study under our research license and option agreement with Sarepta. This further validates the potential of mTOR's platform. Overall, mTOR holds significant promise and has the potential to be revolutionary for the gene therapy fields. We're encouraged by the data generated to date, demonstrating the potential of mTOR to enable repeat dosing by preventing formation of the antibodies, in addition to more durable and robust expression of the transgene after the first dose. Our autoimmune program is advancing through IND enabling studies with an initial focus on primary biliary cholangitis. PBC is a chronic progressive autoimmune liver disorder that leads to inflammation, damage, and scarring of the small bile ducts. It has a well-defined target antigen, significant unmet medical need, and it's well-suited to the application of our intra-immune tolerance class. We expect to file an IND in PBC in the second half of 2022, and we look forward to providing additional updates on this program later this year. Now I'll turn the call over to Brad to run through our financial results for the first quarter and at March 31st, 2021. Brad?