Soligenix Receives FDA Protocol Clearance of Phase 3 Clinical Trial of SGX942

Soligenix announced it received US Food and Drug Administration (FDA) clearance to advance a pivotal Phase 3 clinical trial evaluating SGX942 (dusquetide) for the treatment of oral mucositis in head and neck cancer (HNC) patients being treated with chemoradiation (CRT). Soligenix plans to begin this study in the second quarter of 2017.

Based on positive Phase 2 results (Study IDR-OM-01), the upcoming pivotal Phase 3 clinical trial (Study IDR-OM-02) will be a double-blind, randomized, placebo-controlled, multinational trial that will seek to enroll approximately 190 subjects with squamous cell carcinoma of the oral cavity and oropharynx who are scheduled to receive a minimum total cumulative radiation dose of 55 Gy fractionated as 2.0-2.2 Gy per day with concomitant cisplatin chemotherapy given as a dose of 80-100 mg/m2 every third week.

The study design incorporates feedback from the FDA as well as from the European Medicines Agency (EMA) via the Scientific Advice process. The Scientific Advice from the EMA indicates that a single, double-blind, placebo-controlled, multinational, Phase 3 pivotal study, if successful, in conjunction with results from the Phase 2 dose-ranging study, generally will be considered sufficient to support a marketing authorization application (MAA) for potential licensure in Europe.

"We are pleased to have a pivotal Phase 3 study design that incorporates feedback from both the FDA and EMA, and that has the potential to support marketing approval in both the US and the European Union," Christopher J. Schaber, PhD, President and Chief Executive Officer of Soligenix said. "Study initiation later this year will represent a significant step forward in our oral mucositis development program. We look forward to advancing this pivotal trial in an effort to address the significant unmet medical need that currently exists in this patient population."

Dusquetide (the active ingredient in SGX942) is an innate defense regulator (IDR), a new class of short, synthetic peptides. It has a novel mechanism of action whereby it modulates the body's reaction to both injury and infection towards an anti-inflammatory and an anti-infective response.

SGX942 has demonstrated safety in a Phase 1 clinical study in 84 healthy human volunteers. Recently, SGX942 had positive results in an exploratory Phase 2 clinical study in 111 patients with oral mucositis due to CRT therapy for HNC.

Long-term (12 month) follow-up data further indicated the safety and tolerability of SGX942 treatment, with a sustained trend towards reduced mortality and increased tumor resolution in the 1.5 mg/kg SGX942 treatment group compared to the placebo group. Opioid pain medication use was also seen to decrease over the course of CRT in the 1.5 mg/kg SGX942 treatment group at the point of highest oral mucositis risk, while it increased in the placebo group. Detailed clinical results from the Phase 2 study, as well as a review of the pathogenesis of oral mucositis and the mechanism of action of SGX942, are discussed here.