PRS ( IC50 ≤ 100 nM ); prolyl-tRNA synthetase

Currently, an EPRS1-targeting small molecule inhibitor (named bersiporocin) is under clinical trials to evaluate its therapeutic potential against idiopathic pulmonary fibrosis (ClinicalTrials.gov identifier NCT05389215). This agent binds to the PRS component of EPRS1 and reduces proline-rich collagen synthesis via both translational and nontranslational pathways.[1]

Initially, we determined the dose of the inhibitor/bersiporocin in both in vivo and ex vivo conditions without nephrotoxicity (Supplementary Figure S8). Subsequently, when the inhibitor/bersiporocin was added during ex vivo proliferation of CD4+ or CD8+ T cells, the proliferation rate decreased depending on the inhibitor amount (Figure 5a). The inhibitor/bersiporocin also reduced proliferation and IL-17A production from cultured and stimulated γδ T cells without affecting CD44 expression (Figure 5b–d). When mice were treated with the inhibitor/bersiporocin after TIN induction, tubular injury parameters and cytokine production decreased depending on the inhibitor/bersiporocin amount (Figure 5e; Supplementary Figure S9). Fibrotic transformation of kidneys was lower when the inhibitorbersiporocin was used than when it was not used (Figure 5f and g; Supplementary Figure S10). When the inhibitor/bersiporocin was started from the mid-term in the TIN model (i.e., day 14), the degrees of both tubular injury and fibrosis were lower than those observed when the inhibitor was not used (Figure 5h–j, assessed at 4 weeks; Supplementary Figure S11, assessed at 8 weeks). The inhibitor had nonsignificant or minimal effects on the T cell–depleted condition (i.e., TIN-induced Rag1–/– mice) (Supplementary Figure S12). Collectively, an EPRS1-targeting inhibitor may slow fibrotic transformation after TIN induction by modulating the proliferation and activity of EPRS1high T cells.[1]

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Bersiporocin, a novel first-in-class prolyl-tRNA synthetase (PRS) inhibitor currently under clinical development, was shown to exert an antifibrotic effect through the downregulation of collagen synthesis in various pulmonary fibrosis models. The aim of this first-in-human, randomized, double-blind, placebo-controlled, single- and multiple-dose, dose-escalation study was to evaluate the safety, tolerability, pharmacokinetic (PK) and pharmacodynamic (PD) characteristics of bersiporocin in healthy adults. A total of 40 and 32 subjects were included in a single- (SAD) and multiple-ascending dose (MAD) study, respectively. No severe or serious adverse events were observed after a single oral dose up to 600 mg and multiple oral doses up to 200 mg twice daily for 14 days. The most common treatment-emergent adverse events were gastrointestinal adverse events. To improve the tolerability, initial bersiporocin solution was changed to the enteric-coated formulation. Afterward, the enteric-coated tablet was used in the last cohort of SAD and in the MAD study. Bersiporocin showed dose-proportional PK characteristics after a single dose up to 600 mg and multiple doses up to 200 mg. Upon reviewing the safety and PK data, the final SAD cohort (800 mg enteric-coated tablet) was canceled by the Safety Review Committee. The levels of pro-peptide of type 3 procollagen were lower after treatment with bersiporocin than after the placebo in the MAD study, whereas no significant change was observed in other idiopathic pulmonary fibrosis (IPF) biomarkers. In conclusion, the safety, PK, and PD profile of bersiporocin supported its further investigation in patients with IPF.[2]

A first‐in‐human, randomized, double‐blind, placebo‐controlled, single‐ and multiple‐dose, dose‐escalation study was performed to evaluate the safety, tolerability, PKs, and PDs of bersiporocin in healthy subjects. The study was conducted in two parts in a consecutive order: single‐ascending dose (SAD) study (part I) followed by a multiple‐ascending dose (MAD) study (part II; Figure S3). Each subject was allowed in only one cohort, either in part I or Part II, but not in both parts of the study. Eligible subjects were randomized to either bersiporocin or placebo at a ratio of 6:2 in each dose group (n = 8, each). A sentinel dosing strategy was used in each cohort whereby the first two subjects (one to bersiporocin and the other to placebo) were initially randomized, dosed, and observed for 24 h before proceeding with further randomization of the remaining six. The dose escalation and expansion to the MAD study were based on the decision of the safety review committee (SRC), which consisted of the investigator, the sponsor representative, and two external independent experts.[2]

The starting dose of bersiporocin (100 mg) in the SAD study was below the maximum recommended starting dose for a 60 kg adult, which was calculated as 154.8 mg based on a NOAEL in monkeys (safety factor = 10). The initial planned single dose levels of bersiporocin were between 100 and 1500 mg provided as a 150 mL solution. Nausea and vomiting were observed in five subjects (83.3%) in the starting dose group. Thus, to improve gastrointestinal tolerability, an enteric‐coated capsule formulation was used for the SAD cohort 1b (100 mg), cohort 2 (300 mg), and cohort 3 (600 mg). Afterward, the study drug was once again reformulated to an enteric‐coated tablet to avoid the dissolution of the capsules in the stomach. Based on the cumulative PK data and the predicted biologically active dose from bleomycin‐induced pulmonary fibrosis mouse model, the targeted dose on the human area under the plasma concentration‐time curve (AUC) was calculated to be 170 mg/day. Consequently, the SRC recommended to cancel the 800 mg cohort after reviewing cumulative safety and PK data, and the 500 mg dose level (cohort 4) was the last SAD dose in tablet formation (Figure S3). In part II of the study, the tablet formulation of bersiporocin was administered twice daily (b.i.d.) for 14 days (morning dose only on day 14) at dose levels between 25 and 200 mg in four sequential cohorts (Figure S3).[2]

On study days with intensive PK sample collections (day 1 for the SAD cohorts and the morning doses of day 1 and day 14 for the MAD cohorts), at least 10 h of overnight fasting was required prior to the dosing, and no food was allowed for at least 4 h postdose. For the rest of the doses in the MAD cohorts (i.e., the evening dose on day 1), and all doses administered on day 2 to day 13, the study drug was administered at least 1 h after the last meal, with no food or fluids allowed for at least 1.5 h after each dose. Subjects in the SAD cohort 1 were administered with a 150 mL solution (sweeting agent [Ora‐Sweet] with diluted water) containing bersiporocin 100 mg, and immediately thereafter, the residues in the bottle were rinsed with 90 mL of water. Study drugs supplied as capsules (provided in a 100 or 200 mg strength) or tablets (provided in a 25 or 100 mg strength) were taken with 240 mL of water. [2]

The safety and tolerability of bersiporocin were evaluated throughout the study periods. Serial blood and urine samples were collected to analyze the plasma and urine concentrations of bersiporocin and its metabolites (M1, M8, M10, and M19 for the MAD study only). In the MAD study, serum samples were collected to analyze biomarkers of collagen synthesis and turnover (Pro‐C3, Pro‐C6, C3M, and C6M), which were known to correlate with the disease progression of IPF. CYP2D6 genotyping was conducted in order to explore its possible impacts on PK characteristics on bersiporocin and the major metabolites.[2]

After the administration of a single dose of the oral bersiporocin enteric coated capsule, the plasma concentration of bersiporocin increased in a dose‐proportional manner (Figure 1 and Figure S4). The 90% CI of the slope of the power model included 1.0 (0.36–1.09 [slope estimate; 0.72] and 0.65–1.25 [slope estimate; 0.95], for C max and AUC0‐∞, respectively). The Vz/F, CL/F, and t 1/2 after the multiple dose did not show any dose‐dependent increment or decrement, and considerable PK variability was observed (Table 3). The plasma concentration of bersiporocin reached a C max in the range of 1.50 to 8.00 h postdose and showed a multicompartmental elimination profile (Figure 1) with a t 1/2 of ~6.91 to 9.90 h (Table 3). Comparing the PK parameters after a single dose of bersiporocin 100 mg, the T max was prolonged in both enteric coated formulations and the bioavailability was greatest in enteric coated capsules.[2]

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After multiple administrations of the bersiporocin enteric coated tablet in the MAD study, the plasma concentration of bersiporocin reached a steady‐state on day 2 and accumulated 1.88 to 3.75‐fold by repeated drug administrations (Figure 2 and Table 4). The first Helmert contrast with a p > 0.05 was observed on day 2. The plasma concentration of bersiporocin increased in a dose‐proportional manner after single and multiple doses (Figure 2 and Figure S4 and Table 4). The 90% CI of the slope of the power model included 1.0 (0.79–1.26 [slope estimate; 1.02], 0.75–1.24 [slope estimate; 0.99], and 0.89–1.64 [slope estimate, 1.25] for C max, AUC0‐last, and AUCτ, respectively). However, AUC of bersiporocin increased more than four‐folds in the 100 to 200 mg dose group. The Vz/F, CL/F, and t 1/2 did not exhibit any dose‐dependent increment or decrement, however, CL/F decreased at the day 14 dose compared to the one at the first dose (Table 4). The median T max,ss ranged from 2.0 to 6.0 h and was similar after a single dose (2.5–6 h). The t 1/2 was prolonged after multiple doses compared to the one after a single dose (Tables 3 and 4). The dose adjusted plasma exposure of bersiporocin was six‐ to nine‐fold higher in the CYP2D6 poor metabolizer compared to the median value in other phenotypes (Figure S4). Urine PK data, either from the SAD or MAD, indicated that renal elimination was not the major clearance pathway for bersiporocin (Tables 3 and 4). Four bersiporocin metabolites (M1, M8, M10, and M19) were identified in the plasma, and the plasma exposure of M1 and M8 was higher than those of other metabolites (Table 4). The mean metabolite to parent (bersiporocin) ratio ranged from 2.72 to 14.59 and from 2.45 to 10.93 for M1 and M8, respectively (Table 4). The metabolic ratio showed the tendency to decrease as the dose increased. No significant differences in the dose‐normalized C max or AUCs of bersiporocin were observed among the different CYP2D6 phenotype subjects (Figure S5). However, the dose adjusted plasma exposure of bersiporocin was six‐ to nine‐fold higher in the CYP2D6 poor metabolizer compared to the median value in other phenotypes.2[]

During the SAD study, 90 TEAEs (68 ADRs) were reported in 23 subjects (77%) who received bersiporocin, and 16 TEAEs (3 ADRs) were reported in seven subjects (70%) in the placebo group (Tables 1 and 2 and Table S2). The incidence of ADRs was reduced after changing the bersiporocin formulation from solution to the capsule (12 events in 83% of subjects and 3 events in 50% of subjects in solution and capsule groups, respectively; Table 1). During the MAD study, 150 ADRs were reported in 21 subjects (88%) in the bersiporocin group, and 11 ADRs were reported in three subjects (38%) in the placebo group. Over the dose ranges analyzed in both parts of the study, the number of ADRs tended to increase with the higher doses (Tables 1 and 2). Most ADRs reported in subjects receiving bersiporocin across the study were mild in severity; gastrointestinal disorders were the most common ADRs. There were no severe, life‐threatening, or fatal ADRs across the study.[2]

[1]. Glutamyl-prolyl-tRNA synthetase (EPRS1) drives tubulointerstitial nephritis-induced fibrosis by enhancing T cell proliferation and activity. Kidney Int. 2024 May;105(5):997-1019.

[2]. Safety, tolerability, pharmacokinetic/pharmacodynamic characteristics of bersiporocin, a novel prolyl-tRNA synthetase inhibitor, in healthy subjects. Clin Transl Sci. 2023 Jul;16(7):1163-1176

There were some limitations in this study. First, because this study was conducted with a relatively small number of healthy subjects, the occurrence of gastrointestinal AEs in some of the more susceptible subjects may have contributed to a high overall frequency of AEs in some dose groups. As this study was the first‐in‐human trial of bersiporocin, the PK characteristics of bersiporocin was evaluated in the fasted state to exclude confounding effects of food. However, considering gastrointestinal TEAEs occurred more often in the morning period compared to the evening period, administration of bersiporocin with food might improve its tolerability. Moreover, as most of the gastrointestinal AEs were mild in severity, the tolerability of bersiporocin might be enhanced by other medications, such as anti‐emetics, which needs to be further investigated in future clinical studies. Second, no clear dose–response relationship was observed in the PD biomarkers. Healthy subjects generally had lower serum biomarker levels than patients with IPF, and interindividual variability in the PD biomarker levels may have constituted a reason behind the lack of any clear dose–response relationship observed in this study.[2]
In conclusion, the safety profile of bersiporocin, and its PK and PD profile supported further investigation of this agent in patients with IPF.

C15H19CL2N3O

328.236861467361

327.09

C, 54.89; H, 5.83; Cl, 21.60; N, 12.80; O, 4.87

2241808-52-4

2241808-53-5 (HCl); 2241808-52-4

142411678

Solid powder

2.8

2

3

4

21

347

2

C1C[C@@H]([C@H](NC1)CCCN2C=NC3=C2C=CC(=C3Cl)Cl)O

VXCNMWNXDDMFSX-YPMHNXCESA-N

InChI=1S/C15H19Cl2N3O/c16-10-5-6-12-15(14(10)17)19-9-20(12)8-2-3-11-13(21)4-1-7-18-11/h5-6,9,11,13,18,21H,1-4,7-8H2/t11-,13+/m1/s1

(2R,3S)-2-[3-(4,5-dichlorobenzimidazol-1-yl)propyl]piperidin-3-ol

DWN-12088 Free Base; DWN 12088; UNII-TTU6QSK1G5; 2241808-52-4; TTU6QSK1G5; BERSIPOROCIN [INN]; (2R,3S)-2-(3-(4,5-Dichloro-1H-benzo(d)imidazol-1-yl)propyl)piperidin-3-ol; DWN12088; Bersiporocin

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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 (Please use freshly prepared in vivo formulations for optimal results.)