Efficacy and safety of MYL-1501D versus insulin glargine in patients with type 2 diabetes after 24 weeks: Results of the phase III INSTRIDE 2 study.

AIMS: To assess the non-inferiority of MYL-1501D, a proposed biosimilar or follow-on biological agent to marketed insulin glargine, to reference insulin glargine (Lantus®; Sanofi-Aventis US LLC, Bridgewater, New Jersey) based on change in glycated hemoglobin (HbA1c). MATERIALS AND METHODS: INSTRIDE 2 was a multicentre, open-label, randomized, parallel-group, phase III non-inferiority study comparing the efficacy and safety of MYL-1501D with those of reference insulin glargine in insulin-naive and insulin-non-naive patients with type 2 diabetes mellitus receiving oral antidiabetic drugs (OADs). The primary efficacy endpoint was change in HbA1c from baseline to week 24. Secondary endpoints included metabolic readouts (eg, changes in fasting plasma glucose, insulin dosage, self-monitored blood glucose), immunogenicity and adverse events, including hypoglycaemia and nocturnal hypoglycaemic events. RESULTS: In all, 560 patients were randomized to MYL-1501D or insulin glargine in combination with OADs for 24 weeks. The mean change in HbA1c from baseline to week 24 was -0.60% (95% CI -0.78, -0.41) and - 0.66% (95% CI -0.84, -0.48) for MYL-1501D and reference insulin glargine, respectively. MYL-1501D was well tolerated and had a safety profile similar to that of reference insulin glargine. CONCLUSIONS: Demonstration of non-inferiority between MYL-1501D and reference insulin glargine for reduction of HbA1c during 24 weeks of treatment was achieved. The two treatment groups were similar in terms of secondary endpoints, including hypoglycaemia and nocturnal hypoglycaemia, local and systemic reactions, other safety variables, and immunogenicity.

Efficacy and safety of MYL-1501D vs insulin glargine in patients with type 1 diabetes after 52 weeks: Results of the INSTRIDE 1 phase III study.

AIM: To test the safety and efficacy of MYL-1501D, a proposed insulin glargine biosimilar, in patients with type 1 diabetes mellitus (T1DM). METHODS: The safety and efficacy of MYL-1501D and reference insulin glargine were evaluated in INSTRIDE 1, a 52-week, open-label, randomized, phase III study in patients with T1DM. The primary objective was to determine whether once-daily MYL-1501D was non-inferior to once-daily insulin glargine when administered in combination with mealtime insulin lispro based on change in glycated haemoglobin (HbA1c) from baseline to week 24. Secondary endpoints were changes in fasting plasma glucose, insulin dose, self-monitored blood glucose and immunogenicity from baseline, and occurrences of hypoglycaemic, nocturnal hypoglycaemic and adverse events up to week 52. RESULTS: Overall, 558 patients were randomized 1:1 to MYL-1501D or reference insulin glargine in combination with thrice-daily mealtime insulin lispro for 52 weeks. The mean change in HbA1c from baseline to week 24 was 0.14% (standard error [SE] 0.054; 95% confidence interval [CI] 0.033, 0.244) for MYL-1501D and 0.11% (SE 0.054; 95% CI 0.007, 0.220) for reference insulin glargine. MYL-1501D had a safety profile similar to that of reference insulin glargine and was well tolerated in patients with T1DM up to week 52. CONCLUSIONS: The upper 95% CI limit for mean change in HbA1c at week 24 indicated that MYL-1501D was non-inferior to reference insulin glargine. There were no clinically meaningful differences between groups in incidence of overall and nocturnal hypoglycaemia, local or systemic reactions, safety or immunogenicity.

Serendipitous discovery of a new class of agonists for the melanocortin 1 and 4 receptors and a new class of cyclophanes.

A new class of melanocortin 4 receptor (MC4r) agonists was discovered from an unexpected sidereaction in which formaldehyde caused cyclization. These cyclophanes were found to be sub micromolar agonists of the MC1 and MC4 and were less potent on the MC3 and MC5 receptor. They were shown to compete with the peptidic antagonist SHU9119 for binding to the MC4 receptor. In an acute feeding study in Sprague Dawley rats, food intake was reduced more than 50% versus vehicle after 3 h at a dose of 1 mg/kg.

Physicochemical characteristics and in vitro release from oil-based vehicles of peptidomimetics: parenteral depots for intra-articular administration.

RESULTS: Basic physicochemical properties including their apparent solubility in aqueous buffer and vegetable oils of a series of 11 peptidomimetics varying with respect to chain length and degree of N-methylation were estimated. It was observed that the compounds in contact with water transformed into sticky, slowly dissolving semisolid materials. Based on these observations, the in vitro release behavior of selected peptide derivatives from oil solutions and in situ formed precipitates was investigated using a validated in vitro release model. CONCLUSION: The results of this investigation suggest that both types of oil-based drug delivery systems might constitute alternative sustained release formulation principles of such amorphous peptide derivatives for the intra-articular route of administration.

Library of biphenyl privileged substructures using a safety-catch linker approach.

A biphenyl privileged structure library containing three attachment points were synthesized using a catechol-based safety-catch linker strategy. The method requires the attachment of a bromo-acid to the linker, followed by a Pd-catalyzed Suzuki cross-coupling reaction. Further derivatization, activation of the linker with strong acid and aminolysis afforded the respective products in high purity and good overall yield. To show the versatility of the synthesis, a 199-member library was generated. The library samples both conformational and chemical diversity about a well-known privileged substructure.

Kinetics of degradation and oil solubility of ester prodrugs of a model dipeptide (Gly-Phe).

Oil-based depot formulations may constitute a future delivery method for small peptides. Thus, a requirement is attainment of sufficient oil solubility for such active compounds. A model dipeptide (Gly-Phe) has been converted into lipophilic prodrugs by esterification at the C-terminal carboxylic acid group. The decomposition kinetics of octyl ester of Gly-Phe (IV) has been investigated at pH 7.4 (37 degrees C) and IV was shown to degrade by first-order kinetics via two parallel pathways (1) intramolecular aminolysis resulting in formation of a 2,5-diketopiperazine and (2) hydrolysis of the ester bond producing the dipeptide. The cyclisation reaction was dominating in the decomposition of methyl (II) butyl (III) octyl (IV) decyl (V) and dodecyl (VI) esters of Gly-Phe at pH 7.4. However, this degradation pathway was almost negligible for pH below 6. During degradation of the dipeptide esters in 80% human plasma pH 7.4 (37 degrees C) a minimal amount of cyclo(-Gly-Phe) was formed. A faster degradation of the esters in 80% human plasma pH 7.4 compared to those in aqueous solution pH 7.4 was suggested to be due to fast cleavage of the peptide bond. Low oil solubilities for Gly-Phe and the hydrochlorides of the dipeptide esters III and VI were observed. Although the solubility of Gly-Phe in oil solutions was enhanced by hydrophobic ion pairing with sodium decyl sulfonate the oil solubility was still less than 1 mg Gly-Phe/ml. By addition of a solubiliser, 10% N,N-dimethylacetamide (DMA), to Viscoleo the solubility of the HIP complexes increased significantly. The present study indicates that sufficient oil solubility might only be obtained for relatively small peptides by using the prodrug approach in combination with solubility enhancing organic solvents like DMA.

Recognition of privileged structures by G-protein coupled receptors.

Privileged structures are ligand substructures that are widely used to generate high-affinity ligands for more than one type of receptor. To explain this, we surmised that there must be some common feature in the target proteins. For a set of class A GPCRs, we found a good correlation between conservation patterns of residues in the ligand binding pocket and the privileged structure fragments in class A GPCR ligands. A major part of interior surface of the common ligand binding pocket of class A receptors, identified in many GPCRs, is lined with variable residues that are responsible for selectivity in ligand recognition, while other regions, typically located deeper into the binding pocket, are more conserved and retain a predominantly hydrophobic and aromatic character. The latter is reflected in the chemical nature of most GPCR privileged structures and is proposed to be the common feature that is recognized by the privileged structures. Further, we find that this subpocket is conserved even in distant orthologs within the class A family. Three pairs of ligands recognizing widely different receptor types were docked into receptor models of their target receptors utilizing available structure- activity relationships and mutagenesis data. For each pair of ligands, the ligand-receptor complexes reveal that the nature of the privileged structure binding pocket is conserved between the two complexes, in support of our hypothesis. Only part of the privileged structures can be accommodated within the conserved subpocket. Some contacts are established between the privileged structure and the nonconserved parts of the binding pocket. This implies that any one particular privileged structure can target only a subset of receptors, those complementary to the full privileged structure. Our hypothesis leads to a valuable novelty in that ligand libraries can be designed without any foreknowledge of the structure of the endogenous ligand, which in turn means that even orphan receptors can in principle now be addressed as potential drug targets.

Parallel solid-phase synthesis of disubstituted (5-biphenyltetrazolyl) hydantoins and thiohydantoins targeting the growth hormone secretagogue receptor.

An efficient solid-phase protocol for the synthesis of substituted (5-biphenyltetrazolyl)-hydantoins and -thiohydantoins has been developed. Suzuki cross-coupling between resin-bound 2-(tetrazol-5-yl)-phenylborinane and 4-bromobenzaldehyde gave the corresponding tetrazolylbiphenyl aldehyde. Subsequent reductive amination using amino acid esters gave the pivotal resin bound amino acid esters which were transformed to hydantoins or thiohydantoins via two routes: (i) treatment with isocyanates or isothiocyanates or (ii) successive treatment with triphosgene and primary amines. Using molecular modeling, we were able to jump from L-692,429, a well known non-peptidyl growth hormone secretagogue (GHS), to biphenyltetrazolyl hydantoins, obtaining compounds with IC(50) values below 600 nM after two iterative cycles only.

Kinetics of degradation of 4-imidazolidinone prodrug types obtained from reacting prilocaine with formaldehyde and acetaldehyde.

The kinetics of decomposition of 4-imidazolidinone prodrug types obtained by reacting prilocaine (I) with formaldehyde and acetaldehyde has been studied in aqueous solution in the pH range 1-7.4 at 60 and 37 degrees C, respectively. At pH<5 the hydrolysis of the derivative derived from formaldehyde (II) to yield I obeyed apparent first-order kinetics. At higher pH, the decomposition reactions proceeded to an equilibrium and the reactions could be described by first- and second-order reversible kinetics. A plot of the logarithm of the apparent first-order rate constants for hydrolysis of II against pH resulted in a sigmoidal-shaped pH-rate profile characteristic for the hydrolysis of many N-Mannich bases. A half-life at pH 7.4 (60 degrees C) of 6.9h for compound II was calculated. Compared to II the 4-imidazolidinone derived from acetaldehyde (III) exhibited enhanced instability in aqueous buffer solutions. The decomposition was followed at 37 degrees C monitoring the decrease in concentration of intact (III). At acidic pH the reactions displayed strict first-order kinetics and the disappearance of III was accompanied by a concomitant formation of I. At pH 7.4, the rate data also applied reasonably well to first-order kinetics despite the observation that small amounts of III was formed at pH 7.4 from a solution containing equimolar concentrations of acetaldehyde and prilocaine (10(-4)M). In case of III, a bell-shaped pH-rate profile was obtained by plotting the logarithm of the pseudo-first-order rate constants against pH indicating the involvement of a kinetically significant intermediate in the reaction pathway and a change of the rate-limiting step in the overall reaction with pH. For the stability studies performed at pH 6.9 and 7.4 product analysis revealed that parallel to formation of (I) an unknown compound (X) emerged. Compared to III, compound X is hydrolysed to give I at a slower rate (t(50%)=30 h at 37 degrees C). Based on LC-MS data it is suggested that (X) is an isomeric form of III, which may exist in four diastereomeric forms. Thus, at physiological pH an initial relatively fast regeneration of I from III is to be expected followed by a slower drug activation resulting from hydrolysis of the isomeric form of III.

High constitutive signaling of the ghrelin receptor--identification of a potent inverse agonist.

Ghrelin is a GH-releasing peptide that also has an important role as an orexigenic hormone-stimulating food intake. By measuring inositol phosphate turnover or by using a reporter assay for transcriptional activity controlled by cAMP-responsive elements, the ghrelin receptor showed strong, ligand-independent signaling in transfected COS-7 or human embryonic kidney 293 cells. Ghrelin and a number of the known nonpeptide GH secretagogues acted as agonists stimulating inositol phosphate turnover further. In contrast, the low potency ghrelin antagonist, [D-Arg1,D-Phe5,D-Trp7,9,Leu11]-substance P was surprisingly found to be a high potency (EC50 = 5.2 nm) full inverse agonist as it decreased the constitutive signaling of the ghrelin receptor down to that observed in untransfected cells. The homologous motilin receptor functioned as a negative control as it did not display any sign of constitutive activity; however, upon agonist stimulation the motilin receptor signaled as strongly as the unstimulated ghrelin receptor. It is concluded that the ghrelin receptor is highly constitutively active and that this activity could be of physiological importance in its role as a regulator of both GH secretion and appetite control. It is suggested that inverse agonists for the ghrelin receptor could be particularly interesting for the treatment of obesity.

The influence of conformational restriction in the C-terminus of growth hormone secretagogues on their potency.

In order to obtain more potent growth hormone secretagogues, a comparison of ipamorelin and NN703 suggested the addition of a polar group at the C-terminus of NN703. A study was conducted using constrained amines for this purpose. Here, substituted 4-piperidinylamino- and 4-dimethylaminopiperidino-substituents were found to give the most active compounds. A replacement of the 4-dimethylaminopiperidino-substituent with 4-hydroxypiperidino resulted in a series of compounds, which showed in vitro activity with EC(50) values in the low nanomolar range, and favourable kinetic properties, such as 40% oral bioavailability. The most promising compound was also tested in a swine in vivo model, resulting in a growth hormone level with a C(max) of over 40 ng mL(-1).