Absence of QTc Prolongation with Sodium N-(8-[2-Hydroxybenzoyl] Amino) Caprylate (SNAC), an Absorption Enhancer Co-Formulated with the GLP-1 Analogue Semaglutide for Oral Administration

Abstract

Oral delivery of proteins, including glucagon-like peptide 1 (GLP-1) receptor agonists, is impeded by low gastrointestinal permeation. Oral semaglutide has been developed for once-daily oral administration by co-formulation of the GLP-1 analogue semaglutide with an absorption enhancer, sodium N-(8-[2-hydroxybenzoyl] amino) caprylate (SNAC, 300 mg). A randomised, partially double-blind, placebo-controlled thorough QT/corrected QT (QTc) trial was conducted to confirm the absence of unacceptable QTc interval prolongation with SNAC. QT is defined as interval on the electrocardiogram, measured from the start of the QRS complex to the end of the T wave. Part A of the study sought to identify an appropriate dose of SNAC (which was substantially higher than that used in the oral semaglutide co-formulation) for QTc assessment. Three sequential healthy volunteer cohorts were randomised to escalating single oral doses of SNAC (1.2, 2.4 or 3.6 g) or placebo. Following identification of an appropriate dose, a cross-over trial was conducted (Part B). Healthy volunteers received one of four treatment sequences, including single oral doses of SNAC, moxifloxacin (positive control) and placebo. Primary objectives were to (1) assess adverse events (AEs) with escalating SNAC doses and (2) confirm that SNAC does not cause unacceptable QTc interval prolongation versus placebo, using the Fridericia heart rate-corrected QT interval (QTcF). All subjects completed Part A (N\u2009=\u200936) and 46 subjects completed Part B. In Part A, all AEs were mild to moderate in severity; no relationship was identified between AE incidence and SNAC dose. SNAC 3.6 g, the maximum investigated SNAC dose, was selected for Part B. There was no unacceptable prolongation of the QTcF interval with SNAC 3.6 g, and assay sensitivity was demonstrated with moxifloxacin as the positive control. There was no significant exposure–response relationship between SNAC concentration and QTcF interval, and no instances of QTc interval\u2009>\u2009450 ms or increases\u2009>\u200930 ms. This QT/QTc trial demonstrates that SNAC doses 12-fold higher than the 300 mg dose used in the oral formulation of semaglutide do not cause unacceptable prolongation of the QTcF interval. Clinicaltrials.gov identifier: NCT02911870. Medications that are taken orally can be broken down by acid in the stomach before they are absorbed and therefore be less effective. Oral semaglutide is a novel type 2 diabetes medication that is formulated with the absorption enhancer sodium N-(8-[2-hydroxybenzoyl] amino) caprylate (SNAC), which helps to protect against semaglutide degradation in the stomach. Regulatory authority guidelines recommend that new therapies should be tested for prolongation of the QT interval, an important part of the heart’s electrical cycle. A previous trial demonstrated that semaglutide alone, which is currently available as an injectable diabetes therapy, did not prolong the QT interval when given in doses higher than those used in patients. Therefore, the current trial was conducted to assess whether the SNAC component of oral semaglutide has any relevant prolonging effect on the QT interval. Following regulatory guidelines for trials evaluating prolongation of the QT interval, the first part of the trial aimed to find a suitably high dose of SNAC. The second part of the trial aimed to confirm that SNAC does not prolong the QT interval. The results of this trial demonstrated that a 3.6 g dose of SNAC, which is 12-fold higher than the amount contained in oral semaglutide, does not prolong the QT interval. The safety and tolerability of SNAC 1.2 g, 2.4 g and 3.6 g were assessed in this trial and no concerns were identified. These results, taken alongside those of the previous QT interval study with subcutaneous semaglutide, indicate no relevant effect of oral semaglutide on the QT interval.