Using Target Engagement Biomarkers to Predict Clinical Efficacy of MetAP2 Inhibitors

Abstract

Target-engagement pharmacodynamic (PD) biomarkers are valuable tools in the prioritization of drug candidates, especially for novel, first-in-class mechanisms whose robustness to alter disease outcome is unknown. Methionine aminopeptidase 2 (MetAP2) is a cytosolic metalloenzyme that cleaves the N-terminal methionine from nascent proteins. Inhibition of MetAP2 leads to weight loss in obese rodents, dogs and humans. However, there is a need to develop efficacious compounds that specifically inhibit MetAP2 with an improved safety profile. The objective of this study was to identify a PD biomarker for selecting potent, efficacious compounds and for predicting clinical efficacy that would result from inhibition of MetAP2. Here we report the use of NMet14-3-3g for this purpose. Treatment of primary human cells with MetAP2 inhibitors resulted in an approx. 10-fold increase in NMet14-3-3g levels. Furthermore, treatment of diet-induced obese mice with these compounds reduced body weight (approx. 20%) and increased NMet14-3-3g (approx. 15-fold) in adipose tissues. The effects on target engagement and body weight increased over time and were dependent on dose and administration frequency of compound. The relationship between compound concentration in plasma, NMet14-3-3g in tissue, and reduction of body weight in obese mice was used to generate a pharmacokineticpharmacodynamic-efficacy model for predicting efficacy of MetAP2 inhibitors in mice. We also developed a model for predicting weight loss in humans using a target engagement PD assay that measures inhibitor-bound MetAP2 in blood. In summary, MetAP2 target engagement biomarkers can be used to select efficacious compounds and predict weight loss in humans. SIGNIFICANCE STATEMENT The application of target engagement pharmacodynamic biomarkers during drug development provides a means to determine the dose required to fully engage the intended target and an approach to connect the drug target to physiological effects. This work exemplifies the process of using target engagement biomarkers during preclinical research to select new drug candidates and predict clinical efficacy. We determine concentration of MetAP2 antiobesity compounds needed to produce pharmacological activity in primary human cells and in target tissues from an appropriate animal model and establish key relationships between pharmacokinetics, pharmacodynamics, and efficacy, including the duration of effects after drug administration. The biomarkers described here can aid decision-making in early clinical trials of MetAP2 inhibitors for the treatment of obesity.

Common Genetic Aberrations Associated with Metabolic Interferences in Human Type-2 Diabetes and Acute Myeloid Leukemia: A Bioinformatics Approach

“…More importantly, METAP2 is involved in the metabolism of fat-soluble vitamins [33]. Its inhibition results in weight loss in obese rodents, dogs and humans and has been proposed as a therapeutic target against obesity [45]. On the other hand, METAP2 inhibitors have been shown to induce apoptosis in leukemic cell lines [46], which renders them potent therapeutic agents also for leukemia.…”

Targeting methionine aminopeptidase 2 in cancer, obesity, and autoimmunity

“…Reversible MetAP2i for the treatment of obesity Combining a fragment-based drug discovery approach and optimization iterations based on structural studies, Takeda reported two series of reversible MetAP2i, exemplified by 15 (indazole) and 16 [pyrazolo(4,3-b)indole], showing significant and sustained weight loss in a mouse model of obesity when dosed orally [10,11]. Different parts of these lead compounds were combined to yield 17 [17,55]. Compound 17 reportedly led to sustained weight loss in obese rodents as well as to increased energy expenditure in human adipocytes derived from obese individuals [55].…”

“…Different parts of these lead compounds were combined to yield 17 [17,55]. Compound 17 reportedly led to sustained weight loss in obese rodents as well as to increased energy expenditure in human adipocytes derived from obese individuals [55]. Induced weight loss was caused by direct action of 17 on brown adipocytes [17] in contrast to previous hypotheses positing that weight loss activity was an indirect antiangiogenesis effect in adipose tissue [56].…”

“…First reported as an undesired effect of TNP-470 in the 1990s [1], it took nearly 20 years until MetAP2i were specifically developed for the treatment of obesity and other metabolic disorders [10,11,48]. Most inhibitors reported to induce nontoxic weight loss have also been shown to inhibit endothelial cell proliferation [1,17,48,55], suggesting that both effects depend on MetAP2 inhibition. For Beloranib, reduction of adipose tissue and food intake were reported to require lower doses than vasculature effects [48,50], suggesting differential systemic effects might depend on differential tissue distribution.…”

“…Vasculature-related adverse events halted the development of Beloranib first and then ZFN-1061, the two lead candidates of Zafgen [52,53]. While weight loss activity of MetAP2i was initially thought to be related to angiogenesis inhibition on adipose tissue [56,68], later evidence suggests otherwise, with A-357300, Beloranib, and 17 shown to directly impact the metabolic signature of human primary adipocytes from obese individuals as well as brown adipocytes [17,55].…”