Research ArticleLiver disease

Targeting diacylglycerol acyltransferase 2 for the treatment of nonalcoholic steatohepatitis

See allHide authors and affiliations

Science Translational Medicine  27 Nov 2019:
Vol. 11, Issue 520, eaav9701
DOI: 10.1126/scitranslmed.aav9701
  • Fig. 1 Effect of PF-06427878 on TG metabolism, expression of lipogenic genes, and VLDL-TG secretion kinetics in WTD-fed rats.

    Animals received the indicated dose of PF-06427878 BID (n = 8) for 7 days before determination of (A) hepatic TGs and (B) plasma TGs. WTD, Western-type diet. (C) Expression of lipogenic genes in the livers of rats treated with PF-06427878 (PF7878) for 7 days (30 mg/kg BID). (D) VLDL-TG secretion kinetics in animals on high-sucrose diet (HSD) and treated with single oral dose of PF-06427878, microsomal TG transfer protein inhibitor (MTPi) CP-346086, or vehicle (n = 5). Data are analyzed by one-way ANOVA followed by Dunnett’s multiple comparison test (A to C) and two-way ANOVA followed by Bonferroni’s multiple comparison test (D). *P < 0.05, **P < 0.01, ***P < 0.001 compared with WTD- or HSD-fed animals receiving vehicle. Boxplot whiskers define minimum to maximum. (C and D) Data are means ± SEM. Values in bars are mean values for the threshold cycle in the WTD-fed group (C) and HSD-fed group (D).

  • Fig. 2 Effects of PF-06427878 on the development of liver disease in a STAM NASH-HCC mouse model.

    After the induction of NASH, mice were administered PF-06427878 at 2 mg/kg BID (4 mg/kg per day) or 20 mg/kg BID (40 mg/kg per day) or vehicle alone for 4 weeks and euthanized at 9 weeks of age. (A) Histopathological scoring of hepatic steatosis, hepatocellular ballooning, and lobular inflammation. (B) Calculated NAFLD activity score. (C) Sirius red staining was used to quantitate collagen deposition in the liver. (D) Expression of multiple lipogenic genes in the liver. (E) Expression of genes involved in hepatic stellate cell activation, regulation of fibrosis, myofibroblast function, and extracellular matrix deposition and remodeling in the liver. Data are presented as means ± SEM with n = 8 animals per group. All data are analyzed by one-way ANOVA followed by Dunnett’s multiple comparison compared with vehicle. *P < 0.05, **P < 0.01, ***P < 0.001. ns, not significant.

  • Fig. 3 Representative photomicrographs of H&E- and Sirius red–stained sections in a STAM NASH-HCC mouse model.

    After the induction of NASH, mice were administered PF-06427878 at 2 mg/kg BID (4 mg/kg per day) or 20 mg/kg BID (40 mg/kg per day) or vehicle alone for 4 weeks (n = 8 animals per group) and euthanized at 9 weeks of age. Livers were collected for histopathological analysis. Sections were cut from paraffin blocks of liver tissue prefixed with Bouin’s solution and stained with H&E or Sirius red. (A) H&E stain of the liver from vehicle- and PF-06427878–treated mice. Micro- and macrovesicular lipid deposition in hepatocytes are shown by the white arrow and black arrowhead, respectively; ballooning degeneration of hepatocytes is shown by the black arrow. Scale bars, 100 μm. (B) Sirius red stain liver sections from vehicle- and PF-06427878–treated mice. Reductions in perivenular collagen are shown by black arrows. Scale bars, 100 μm.

  • Fig. 4 Liver function tests on day 14 relative to baseline after multiple doses of placebo or PF-06427878 in healthy humans (studies B7871002 and B7871005).

    The boxplot includes median (horizontal line within box) and arithmetic mean (large open diamond within box), with 25th and 75th percentiles and whiskers to the last point within the 1.5× interquartile range and outliers in open circles. Baseline is defined as the predose measurement on day 1. PF-06427878 15, 45, 150, 450, and 1500 mg/day: n = 8, 12, 6, 8, 8, 8, and 12, respectively. *P < 0.05, **P < 0.01, ***P < 0.001, Williams’ test. Δ, change from baseline; Placeboa, study B7871002; Placebob, study B7871005.

  • Fig. 5 Reductions in liver fat on day 15 relative to baseline after multiple doses of placebo or PF-06427878 in humans (study B7871005).

    Reductions in liver fat were assessed using MRI-PDFF. Boxplot includes median (horizontal line within box) and arithmetic mean (solid diamond within box), with 25th and 75th percentiles and whiskers to last point within 1.5× interquartile range, with baseline defined as value as assessed on day −1 (n = 12 per group). P values were calculated from the differences between placebo and active treatment group LS means in the logarithmic scale. **P < 0.01.

  • Table 1 Summary of in vitro pharmacologic activity and nonclinical and clinical pharmacokinetic properties of PF-06427878.

    Summary of in vitro pharmacologic activity and nonclinical and clinical pharmacokinetic properties of PF-06427878.. Fa determined after 10 mg/kg of oral dose in 0.5% methylcellulose. CYP, cytochrome P450; DGAT1, diacylglycerol acyltransferase 1; DGAT2, diacylglycerol acyltransferase 2; IC50, half maximal inhibitory concentration; MGAT1, monoacylglycerol acyltransferase 1; MGAT2, monoacylglycerol acyltransferase 2; MGAT3, monoacylglycerol acyltransferase 3; AUCinf, area under the plasma concentration time profile from 0 extrapolated to infinity; AUClast, area under the plasma concentration time profile from 0 to the last quantifiable concentration; AUCtau, area under the plasma concentration time profile from time 0 to time tau (τ), where τ equals 8 hours; Cmax, maximum plasma concentration; CV, coefficient of variation; n, number of participants in the treatment group and contributing to the summary statistics; n1, number of participants for AUCinf and t1/2; NA, not applicable; NR, not reported; PK, pharmacokinetics; Q8H, every 8 hours; t1/2, terminal elimination half-life; Tmax, time for Cmax.

    AssayPharmacodynamic activity
    Recombinant enzyme inhibition assays: DGAT2
    Human DGAT2, IC50 (nM)99.9 ± 3.2*
    Rat DGAT2, IC50 (nM)202 ± 4.4*
    Recombinant enzyme inhibition assays: Selectivity
    Human DGAT1, IC50 (μM)>50
    Mouse MGAT1, IC50 (μM)>50
    Human MGAT2, IC50 (μM)>45
    Human MGAT3, IC50 (μM)>50
    Primary hepatocyte assays
    Human DGAT2, IC50 (nM)11.6 ± 1.3*
    Nonclinical pharmacokinetic properties
    Fraction unbound (Fu), human/rat plasma0.046/0.038
    Fraction absorbed in rat, Fa (%)78.0
    Total plasma clearance, rat, CLp (ml/min per kg)31.4
    Human CYP1A2, CYP2B6, CYP2C9, CYP2C19, CYP2D6, and CYP3A4/5 inhibition, IC50 (μM)>100
    *Means ± SEM
    Clinical pharmacokinetic properties
    n, n1Cmax (ng/ml)Tmax (hours)t1/2 (hours)AUCinf (ng·hour/ml)AUCtau (ng·hour/ml)
    Single ascending doses of PF-06427878*
    3 mg6, 16.3 (48)2.0 (0.5–3.0)NRNRNA
    10 mg6, 425.5 (74)1.5 (0.5–3.0)1.6 ± 0.381.4 (49)NA
    30 mg6, 672.0 (30)2.0 (0.5–4.0)1.7 ± 0.2242.0 (20)NA
    100 mg6, 6244.1 (26)3.1 (0.5–4.0)3.0 ± 0.9870.2 (57)NA
    300 mg6, 31092 (28)1.5 (1.0–4.0)5.2 ± 1.73046 (37)NA
    600 mg6, 51728 (41)2.0 (1.0–2.0)4.4 ± 2.25867 (33)NA
    1200 mg6, 54072 (34)2.0 (0.5–4.0)5.3 ± 2.217940 (21)NA
    2000 mg6, 59302 (63)4.0 (3.0–6.0)5.0 ± 1.043830 (41)NA
    Multiple doses of PF-06427878 with plasma PK assessed on day 14*,
    15 mg/day6, 111.2 (43)1.0 (1.0–1.0)NRNR21.5 (67)
    45 mg/day8, 439.0 (44)1.0 (1.0–2.1)7.6 ± 3.7NR109.0 (40)
    150 mg/day8, 2127.5 (51)1.0 (1.0–3.0)NRNR299.8 (54)
    450 mg/day8, 5476.4 (72)1.0 (1.0–2.0)10.3 ± 3.4NR1208 (63)
    1500 mg/day12, 101254 (69)1.0 (0.5–3.9)6.2 ± 2.4NR4403 (54)

    *Geometric mean (%CV) for all PK parameters except: median (range) from Tmax; arithmetic means ± SD for t1/2.

    †The mean value of AUClast was higher than AUCinf when AUCinf was not reportable in individual participant(s) with high AUClast value(s).

    ‡Daily administration divided Q8H with a meal.

    • Table 2 Adverse events reported by two or more healthy adult participants after repeated oral dosing of a range of PF-06427878 doses in humans (studies B7871002 and B7871005).

      Adverse events reported by two or more healthy adult participants after repeated oral dosing of a range of PF-06427878 doses in humans (studies B7871002 and B7871005)..

      Placebo*PF-06427878 dose per day (administration divided Q8H with a meal)
      15 mg45 mg150 mg450 mg1500 mg
      Number of
      participants per
      group
      20688912
      BMI, kg/m2, median
      (range)
      31.0 (24.6–44.7)26.1 (24.0–27.6)24.8 (21.4–30.2)26.8 (23.6–35.1)27.6 (25.5–31.5)33.8 (27.1–40.2)
      Number of healthy adult participants with specific adverse events
      Diarrhea201020
      Abdominal pain201100
      Headache201100
      Dyspepsia200100
      Nasal dryness102000
      Constipation010011
      Flatulence002000
      Gastroenteritis100010

      *Combining participants randomized to placebo in study B7871002 (n = 8) and B7871005 (n = 12).

      †Adverse event of moderate intensity; all other adverse events were mild in intensity.

      • Table 3 Effect of repeated oral dosing of PF-06427878 on serum fasting (studies B7871002 and B7871005) and postprandial (study B7871005) TG concentrations in humans.

        Effect of repeated oral dosing of PF-06427878 on serum fasting (studies B7871002 and B7871005) and postprandial (study B7871005) TG concentrations in humans.. Data are presented from studies B7871002 and B7871005 separately to showcase the effect with increasing doses of PF-06427878 with comparison to within-study placebo. Daily administration of PF-06427878 was divided Q8H with a meal. CI, confidence interval; LS, least squares; and TG, triglycerides.

        Dose (mg/day)n% Change from baselinePlacebo-adjusted % change from baseline
        Adjusted
        geometric LS
        means
        80% CIAdjusted
        geometric LS
        means
        80% CIP
        Fasting serum TG concentrations
        Study B7871002
        Placebo8−0.9−10.1 to 9.2
        PF-06427878, 15 mg6−8.2−17.9 to 2.7−7.3−20.1 to 7.50.5086
        PF-06427878, 45 mg8−5.4−14.2 to 4.2−4.5−16.8 to 9.50.6608
        PF-06427878, 150 mg8−22.5−29.7 to −14.6−21.8−31.8 to −10.30.0254
        PF-06427878, 450 mg8−9.5−17.9 to −0.3−8.7−20.38 to 4.70.3928
        Study B7871005
        Placebo12−24.5−34.4 to −13.1
        PF-06427878, 1500 mg12−16.4−27.3 to −3.810.8−9.2 to 35.00.5034
        Postprandial TG concentrations
        Study B7871005
        Placebo12−21.0−29.9 to −10.9
        PF-06427878, 1500 mg12−20.0−29.4 to −9.21.3−14.9 to 20.50.9236

      Supplementary Materials

      • stm.sciencemag.org/cgi/content/full/11/520/eaav9701/DC1

        Materials and Methods

        Fig. S1. Chemical structure of PF-06427878.

        Fig. S2. Effect of PF-06427878 on circulating hepatic biomarkers in Wistar Han IGS rats and cynomolgus monkeys in 2-week toxicology studies.

        Fig. S3. Subject disposition in clinical studies of PF-06427878 in healthy humans.

        Fig. S4. Descriptive summary (n, means, and SEM) and individual participant–level MRI-PDFF data for liver fat in humans (study B7871005).

        Table S1. Effect of PF-06427878 on selected clinical chemistry parameters in the STAM mouse model of NASH.

        Table S2. Effect of PF-06427878 on fasting serum lipids on day 14 in studies B7871002 and B7871005.

        Data file S1. Raw data from nonclinical in vivo studies.

      • The PDF file includes:

        • Materials and Methods
        • Fig. S1. Chemical structure of PF-06427878.
        • Fig. S2. Effect of PF-06427878 on circulating hepatic biomarkers in Wistar Han IGS rats and cynomolgus monkeys in 2-week toxicology studies.
        • Fig. S3. Subject disposition in clinical studies of PF-06427878 in healthy humans.
        • Fig. S4. Descriptive summary (n, means, and SEM) and individual participant–level MRI-PDFF data for liver fat in humans (study B7871005).
        • Table S1. Effect of PF-06427878 on selected clinical chemistry parameters in the STAM mouse model of NASH.
        • Table S2. Effect of PF-06427878 on fasting serum lipids on day 14 in studies B7871002 and B7871005.
        • Legend for Data file S1

        [Download PDF]

        Other Supplementary Material for this manuscript includes the following:

        • Data file S1 (Microsoft Excel format). Raw data from nonclinical in vivo studies.

      Stay Connected to Science Translational Medicine

      Navigate This Article