Selecta Biosciences Presents New Data at 2019 American College of Rheumatology Annual Meeting from Phase 2 Study of SEL-212 for the Treatment of Patients with Chronic Refractory Gout

Nov 11, 2019

– Data demonstrate SEL-212 efficacy, reduction in the incidence of gout flares and support for dose selection in the ongoing head-to-head COMPARE trial and in future
Phase 3 clinical studies –

– Enrollment in the COMPARE trial expected to complete by the end of 2019; interim data to be reported in Q1 2020, and top-line statistical superiority data expected by mid-2020

WATERTOWN, Mass., Nov. 11, 2019 (GLOBE NEWSWIRE) -- Selecta Biosciences, Inc. (NASDAQ: SELB), a clinical-stage biotechnology company focused on unlocking the full potential of biologic therapies based on its immune tolerance platform technology, ImmTOR™, today announced new data from their Phase 2 dose-ranging study evaluating SEL-212, a combined therapy of ImmTOR + pegadricase for the treatment of chronic refractory gout. Results reinforce that, in the five monthly combination cohorts, SEL-212 is effective in reducing incidence of gout flares and supports dose selection in the head-to-head COMPARE clinical trial and in future Phase 3 studies. These data are being presented at the 2019 American College of Rheumatology (ACR) Annual Meeting in Atlanta, GA.

“The results presented today build on previous evidence demonstrating that SEL-212 could potentially change the treatment paradigm for patients with chronic refractory gout. The data show reduction in flares and a decrease of anti-drug antibody levels, leading to sustained lower serum uric acid levels in patients treated monthly with SEL-212 over five months”, said Carsten Brunn, PhD, President and CEO of Selecta Biosciences. “We are extremely excited to share these data, as they provide important context for the upcoming interim readout of the head-to-head COMPARE trial in Q1 2020, and the top-line statistical superiority data in the middle of 2020.”

Data from the abstract entitled “Monthly Dosing of ImmTOR Tolerogenic Nanoparticles Combined with Pegylated Uricase (Pegadricase) Enables Sustained Reduction of Acute Gout Flares in Symptomatic Gout Patients” showed that monthly dosing of SEL-212 enables sustained reduction of acute gout flares. In month one, 50% of patients who received pegadricase alone had flares, compared to 35% receiving SEL-212. Further, zero patients receiving SEL-212 had initial flares after the second month of treatment.

The abstract entitled “Phase 2 Dose-Ranging Study of SEL-212 in Symptomatic Gout Patients: Selection of Doses for Further Clinical Development” evaluated symptomatic gout patients treated with pegadricase at 0.2 or 0.4 mg/kg alone or combined with 0.05 to 0.15 mg/kg ImmTOR. Results showed that when administered alone at either dose, pegadricase resulted in a rapid reduction in sUA, which was not sustained due to anti-drug antibodies (ADA) formation in 5 of 6 patients. The addition of ImmTOR at ≥0.1 mg/kg reduced ADA formation, allowing sustained reduction in sUA, but these responses were attenuated when ImmTOR was removed during cycles 4 and 5. The combination of pegadricase (0.2 mg/kg) and ImmTOR (0.1 or 0.15 mg/kg) was given during all 5 cycles in 3 additional cohorts. In these cohorts, 66% of evaluable patients (21/32) maintained sUA levels below 6 mg/dL at Week 20 after 5 monthly doses of SEL-212, and 100% of patients who had sUA <6 mg/dL at 12 weeks, maintained control through 20 weeks. Sustained reduction of sUA levels correlated with low or no ADAs. The percentage of patients experiencing flares in these three cohorts declined from 35% during month 1 to 9%-10% during months 3, 4, and 5. These data led to the selection of a combination of pegadricase (0.2 mg/kg) and ImmTOR (0.15 mg/kg) in the head-to-head COMPARE study of SEL-212 and pegloticase, a pegylated uricase currently FDA approved for use in patients with treatment-refractory gout.

In an abstract entitled “Monthly Dosing of ImmTOR Tolerogenic Nanoparticles Combined with Pegylated Uricase (Pegadricase) Mitigates Formation of Anti-Drug Antibodies Resulting in Sustained Uricase Activity in Symptomatic Gout Patients” subjects were infused with SEL-212 in 28-day cycles, up to 5 times. Safety, tolerability, sUA, ADAs, and uricase activity were monitored, and data demonstrated that patients taking SEL-212 had titers <1080, uricase activity AUCs sustained over 5 treatment periods, and low sUA. These results conclude that when anti-uricase titers are less than 1080, patients showed sustained uricase activity, enabling 28-day treatment intervals and further supporting the once-monthly dosing regimen for SEL-212. Further, results showed that SEL-212 was generally well tolerated at clinically active doses following repeated administrations in the trial.

SEL-212 is a novel combination product candidate designed to sustain control of sUA in patients with chronic refractory gout, potentially reducing harmful tissue urate deposits which, when left untreated, can lead to debilitating gout flares and joint deformity. SEL-212 consists of pegadricase, the company’s proprietary pegylated uricase, co-administered with ImmTOR, designed to mitigate the formation of anti-drug antibodies (ADAs). ADAs develop due to unwanted immune responses to biologic medicines, rendering these therapies less potent, which remains an issue across multiple therapeutic modalities and disease states including chronic refractory gout.

About Chronic Refractory Gout
Gout is the most common form of inflammatory arthritis with more than 8.3 million patients in the United States having been diagnosed with gout, which is caused by high levels of uric acid in the body that accumulate around the joints and other tissues, and can result in flares that cause intense pain. Approximately 160,000 patients in the United States suffer from chronic refractory gout, a painful and debilitating condition in which patients are not able to get their SUA levels below 6 mg/dL and therefore have several flares per year and can develop nodular masses of uric acid crystals known as tophi. Elevated SUA levels have been associated with diseases of the heart, vascular system, metabolism, kidney and joints.

About Selecta Biosciences, Inc.
Selecta Biosciences, Inc. is a clinical-stage biotechnology company focused on unlocking the full potential of biologic therapies based on its immune tolerance technology (ImmTOR) platform. Selecta plans to combine ImmTOR with a range of biologic therapies for rare and serious diseases that require new treatment options due to high immunogenicity. The company’s current proprietary pipeline includes ImmTOR-powered therapeutic enzyme and gene therapy product candidates. SEL-212, the company’s lead product candidate, is being developed to treat chronic refractory gout patients and resolve their debilitating symptoms, including flares and gouty arthritis. Selecta’s proprietary gene therapy product candidates are in preclinical development for certain rare inborn errors of metabolism and incorporate ImmTOR with the goal of addressing barriers to repeat administration. Selecta is based in Watertown, Massachusetts. For more information, please visit

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 progress of the clinical development of SEL-212, expectations surrounding the enrollment and design of the Phase 2 head-to-head (COMPARE) clinical trial comparing SEL-212 and Krystexxa, timing of related data readouts and the ability of the COMPARE results to inform the planned Phase 3 clinical trial of SEL-212, the anticipated timing of the planned Phase 3 clinical trial, whether the head-to-head trial with Krystexxa will demonstrate superiority, the unique proprietary technology platform of the company and the unique proprietary platform of its partners, the potential of SEL-212 to fulfill unmet needs in chronic refractory gout patients including sustained SUA reduction, reduced flares, and once monthly dosing, the company’s commercial plans, the ability of the company’s ImmTOR platform, including SEL-212, to unlock the full potential of biologic therapies, the potential of SEL-212 to treat chronic refractory gout patients and resolve their debilitating symptoms, the potential treatment applications for product candidates utilizing the ImmTOR platform in areas such as enzyme therapy, the company’s plan to apply its ImmTOR technology platform to a range of biologics for rare and serious diseases, the potential of the ImmTOR technology platform generally and the company’s ability to grow its strategic partnerships, the sufficiency of the company’s cash, cash equivalents and short-term investments, 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 availability and timing of data from ongoing and future clinical trials and the results of such trials, whether preliminary results from a particular clinical trial will be predictive of the final results of that trial or whether results of early clinical trials will be indicative of the results of later clinical trials, the unproven approach of the company’s ImmTOR technology, potential delays in enrollment of patients, undesirable side effects of the company’s product candidates, its reliance on third parties to manufacture its product candidates and to conduct its clinical trials, the company’s inability to maintain its existing or future collaborations, licenses or contractual relationships, its inability to protect its proprietary technology and intellectual property, management’s ability to perform as expected, potential delays in regulatory approvals, the availability of funding sufficient for its foreseeable and unforeseeable operating expenses and capital expenditure requirements, the company’s recurring losses from operations and negative cash flows from operations raise substantial doubt regarding its ability to continue as a going concern, substantial fluctuation in the price of its common stock, and other important factors discussed in the “Risk Factors” section of the company’s most recent Quarterly Report on Form 10-Q, and in other filings that the company makes with the Securities and Exchange Commission. 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 intention to update any forward-looking statements included in this press release.

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Solebury Trout

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Source: Selecta Biosciences, Inc.