Results from in vitro and in vivo studies evaluating the bioavailability, effects of food, and administration as crushed tablet suspension on vericiguat pharmacokinetics
AAPS Open volume 8, Article number: 16 (2022)
This article describes in vitro and in vivo studies that aimed to further characterize the biopharmaceutical properties and pharmacokinetic (PK) profile of vericiguat and to guide dosing recommendations.
Five open-label, phase I studies characterized the biopharmaceutical aspects of vericiguat, including absolute bioavailability, bioavailabilities of different formulations, dose proportionality, and food effect. Area under the curve (AUC) and maximum plasma concentrations (Cmax), determined by a noncompartmental analysis, were compared by analysis of variance, and a mixed-effects power model was used to assess dose proportionality. The effect of food on the dissolution of vericiguat was evaluated in vitro using media simulating the gastrointestinal tract under fed and fasted conditions. In vitro dissolution of intact vs crushed vericiguat tablet was assessed in quality control medium (HCl at pH 2), acetate buffer at pH 4.5, and phosphate buffer at pH 6.8.
Dissolution of vericiguat increased under fed conditions. In healthy subjects, exposure (AUC and Cmax) increased ~ 40% with food vs fasted state (10 mg intact tablet) confirming a food effect on vericiguat bioavailability. Interindividual variability in exposure decreased ~ 20%, irrespective of meal type. Absolute bioavailability of vericiguat 10 mg (intact tablets, fed) was 93%. Vericiguat 2.5–10 mg demonstrated dose proportionality (intact tablets, fed) in healthy subjects. Dissolution studies showed no differences between the formulations, and this was confirmed with in vivo studies.
Vericiguat tablets should be administered with food and may be crushed for patients who have difficulty swallowing.
Vericiguat is a soluble guanylate cyclase stimulator, indicated to reduce the risk of cardiovascular death and heart failure (HF) hospitalization following a hospitalization for HF or need for outpatient intravenous (IV) diuretics, in adults with symptomatic chronic HF and ejection fraction less than 45% (Food and Drug Administration 2021a). The recommended starting dose of vericiguat is 2.5 mg orally once daily with food. The dose should be doubled approximately every 2 weeks to reach the target maintenance dose of 10 mg once daily, as tolerated by the patient (Food and Drug Administration 2021a).
Within the clinical development program, several formulations of vericiguat were investigated (Supplementary Table S1); however, vericiguat was primarily administered as immediate-release (IR) tablets with a non-functional film coating. Vericiguat has low solubility, high permeability, and is a weakly basic compound (Becker et al. 2019), in line with a Biopharmaceutics Classification System (BCS) class II drug (Food and Drug Administration 2017). Vericiguat IR tablets have predictable pharmacokinetics (PKs), with peak plasma concentration reached at approximately 4 h after oral administration with food in healthy adults and a mean elimination half-life of approximately 20–24 h (Boettcher et al. 2021a; European Medicines Agency 2021), consistent with a pharmacological profile suitable to once daily dosing. In phase I studies, vericiguat was generally well-tolerated and most treatment-emergent adverse events (TEAEs) were of mild intensity (Boettcher et al. 2021a). The most frequent TEAE in the discussed studies were “headache”, “nasopharyngitis”, “increased blood creatine phosphokinase”, “nausea”, and “dyspepsia”, reported in 33.3%, 10.8%, 7.8%, 5.9%, and 5.9% of subjects, respectively. The hemodynamic effects of vericiguat were evaluated and found to be consistent with its mode of action (Boettcher et al. 2021a). Vericiguat also has a low potential for PK and pharmacodynamic interactions with other frequently prescribed medicines (Boettcher et al. 2020, 2021b). Glucuronidation to produce the pharmacologically inactive metabolite, M-1, is the main metabolic pathway of vericiguat; 53% is excreted in urine (primarily as M-1) and 45% in feces (primarily as vericiguat) (Boettcher et al. 2020).
Here, we describe the results of five phase I studies that aimed to further characterize the biopharmaceutical properties and PK profile of vericiguat. The studies evaluated the absolute oral bioavailability and general biopharmaceutical characteristics of different formulations and doses of vericiguat in the fed and fasted states, including the effect of different types of meals (high-fat, high-calorie or low-fat, low-calorie meal). As the presence of food alters the components of gastrointestinal fluid, in vitro dissolution studies with simulated intestinal fluids (representing fed and fasted states) were also performed. The findings of these studies informed the choice of dose administration (with food) in the phase IIb SOCRATES studies (NCT01951625 and NCT01951638) and the phase III VICTORIA trial (NCT02861534), and the recommendation in the prescribing information to take vericiguat with food (Food and Drug Administration 2021a).
Some patients with chronic HF that may require treatment with vericiguat, such as those who are geriatric, hospitalized, seriously ill, or have multiple comorbidities, may be fed by nasogastric tube or be unable to swallow the whole tablet formulation; therefore, crushing the whole tablet formulation offers an alternative approach to whole tablets and is of clinical value (Food and Drug Administration 2018). Thus, an additional aim of the phase I studies was to evaluate the PK and bioavailability of vericiguat administered as a crushed tablet suspension relative to the intact tablet, to guide dosing recommendations for this patient group. To support this clinical study, in vitro studies were conducted to examine the influence of crushing the tablet on dissolution.
Materials and methods
In vitro studies
Solubility and permeability
The solubility of vericiguat was determined by adding crystalline drug substance in excess to aqueous media (hydrochloric acid [HCl] pH 2, glycine buffer pH 3, acetate buffer pH 4.5, and phosphate buffer pH 6.8). Suspensions were stirred at 37 °C for 24 h. The suspensions were then passed through a 0.45-μm membrane filter, and the clear filtrate was analyzed by high-performance liquid chromatography (HPLC) for vericiguat content.
The permeability of vericiguat was determined as previously described for the apical (A) to basal (B) and B-to-A orientation at 2 μM using a validated Caco-2 cell assay (International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) 2019; Wunder et al. 2009).
Evaluation of dissolution
Fed vs fasted state
To support in vivo PK observations in the fed and fasted states, the effect of food on dissolution was evaluated using media simulating the gastrointestinal tract under fed and fasted conditions. Intact vericiguat tablets at doses of 2.5 mg, 5 mg, and 10 mg were added to 500 mL of fasted-state simulated intestinal fluid (FaSSIF) and 500 mL of fed-state simulated intestinal fluid (FeSSIF). Both FaSSIF and FeSSIF were prepared according to the manufacturer´s instructions (www.biorelevant.com, accessed Feb 28, 2022). Dissolution studies were performed at 37 °C using United States Pharmacopeia 2 paddle apparatus with a stirring speed of 75 rpm. Ten milliliters of samples manually drawn from each of the dissolution vessels at time points 5, 10, 15, 20, 30, 40, 50, and 60 min were filtered using 0.45 µm regenerated cellulose filters (Whatman Spartan, Cytiva, Germany). For each sampling time point and vessel, a fresh filter was used. Pre-rinse volume for filtration was 6 mL. Withdrawn sampling volume was replaced by adding 10 mL of fresh FaSSIF or FeSSIF medium to each vessel after every sampling time point, respectively. Vericiguat content in the filtrate was determined by HPLC with UV-detection (Agilent, Waldbronn, Germany; Supplementary Table S2).
Crushed vs intact tablets
To investigate the influence of crushing the tablet, dissolution of intact tablet and crushed tablet suspension (2.5 mg and 10 mg) were compared in the quality control medium (900 mL 0.01 M HCl; pH 2) as well as in 900 mL of acetate buffer pH 4.5 and 900 mL of phosphate buffer pH 6.8, respectively. Dissolution studies were performed at 37 °C using United States Pharmacopeia 2 paddle apparatus with a stirring speed of 75 rpm. Ten milliliters of samples manually drawn from each of the dissolution vessels at time points 15, 30, 45, and 60 min were filtered using either 0.45 µm regenerated cellulose filters (Whatman Spartan, Cytiva, Germany; for each sampling time point and vessel, a fresh filter was used; pre-rinse volume for filtration was 6 mL; withdrawn sampling volume was replaced by adding 10 mL of fresh dissolution medium to each vessel after every sampling time point, respectively), or validated filter equivalents (e.g., G4 glass frit as part of the fully automated dissolution system RoboDisI, Erweka, Germany). Filtrates were subjected to quantification by validated HPLC methods (Agilent, Waldbronn, Germany; Supplementary Table S2).
The preparation of the tablet suspensions for in vitro dissolution testing followed the suspension preparation conducted for the vericiguat coated tablet 10 mg in the respective human PK study (Supplementary Table S1).
As the tablet suspension may sit for a few hours after preparation until administration in the clinical setting, a short-term stability study over 4 h was conducted for the crushed tablet suspension, consistent with the regulatory guidance (Food and Drug Administration 2018). For crushed tablets, dissolution was evaluated for the suspension applied to the dissolution medium immediately and 4 h (at room temperature) after preparation. Statistical comparison of dissolution curves was performed using the F2 test according to guidelines (International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) 2019; Moore and Flanner 1996; Food and Drug Administration 2021).
Phase I clinical studies
Five separate, open-label, non-placebo-controlled, single-dose, and single-center clinical studies (Table 1) were conducted between December 2011 and August 2017. All studies, except for the absolute bioavailability study, were crossover studies comparing multiple treatment regimens, with subjects randomized to treatment sequence. Healthy, white, male subjects aged ≥ 18 and ≤ 55 years with a body mass index (BMI) of ≥ 18.0 and ≤ 30.0 kg/m2 who provided written informed consent were eligible for participation. Exclusion criteria included the use of regular medication within 4 weeks of study drug administration and the use of medications that may have interfered with the study drug at least 2 weeks prior to dosing. Studies met all local and regulatory requirements and were conducted in accordance with the currently accepted version of the Declaration of Helsinki and the International Conference on Harmonization Good Clinical Practice (GCP) Guideline.
The oral formulations used in the studies were intact IR tablets, crushed IR tablets suspended in water, and a polyethylene glycol (PEG) solution formulation (Supplementary Table S1). Vericiguat was also administered as an IV infusion in the absolute bioavailability study. These four vericiguat formulations are referred to here as: intact tablets, crushed tablet suspension, PEG solution, and IV infusion.
Relative bioavailability and food effect study
The bioavailability of vericiguat intact tablets (1.25 mg and 5 mg) relative to that of PEG solution (5 mg) was assessed in a four-way crossover study (Study 2011–004,841-42; Table 1). The PEG solution was the formulation utilized in the first-in-human (FIH) studies, because the FIH studies were performed before the tablet formulation was completed and because this oral solution allows all dosing increments to be administered while ensuring independence of dissolution. This study compared the PEG and tablet formulations to bridge the results from the FIH studies. The study also investigated the effect of food (high-fat, high-calorie meal) on the PK of the intact tablet (5 mg).
Evaluation of absolute bioavailability
The absolute bioavailability of a single oral dose of vericiguat 10 mg, administered as two 5 mg intact tablets in the fed state, was characterized using a micro-dose approach (Study 2015–001,568-20; Table 1). The study utilized simultaneous administration of oral vericiguat and a 14C-labeled micro-dose of 20 μg vericiguat as a comparator. The micro-dose was administered as a 30-min IV infusion, 4 h after oral tablet dosing, coinciding with the approximate time (Tmax) to reach maximum plasma concentration (Cmax) of the intact tablet formulation.
Dose proportionality of vericiguat administered as intact tablets was examined in two studies (Study 2012–004,839-23 and Study 2016–000,980-18; Table 1), across the dose range 1.25 mg to 10 mg.
Evaluation of food effects and meal type
The effect of food on vericiguat PK was characterized in the pivotal food effect and dose proportionality study (Study 2016–000,980-18; Table 1). Vericiguat was administered either without food (fasted state) or with a high-fat, high-calorie or a low-fat, low-calorie meal (fed state). Meals were ingested 30 min before treatment. When vericiguat was taken in the fasted state, subjects underwent an overnight fast for at least 10 h before receiving the study drug. Drinking of water was permitted until 2 h pre-dose. Food and beverages on the day of dosing were standardized. Neither were allowed during the first 2 h post-dose. Water consumption only (up to 250 mL) was allowed 2–4 h post-dose. Subjects received a standardized lunch, snack, and dinner (approximately 4, 8, and 12 h post-dose, respectively).
In line with international regulatory guidelines and recommendations for food effect studies, the high-fat, high-calorie meal contained 50% fat, with calorific content at approximately 800–1000 kcal (Food and Drug Administration 2002). Conversely, in line with draft guidance, the low-fat, low-calorie meal contained 25% fat, with calorific content at 407 kcal (Food and Drug Administration 2019). A content breakdown of test meals by carbohydrate, fat, and protein content is given in Table 2.
Relative bioavailability of crushed tablets
The bioavailability of a crushed tablet suspension of vericiguat (10 mg) was examined relative to intact tablets (10 mg) under fed conditions (Study 2016–005,074-35; Table 1).
Study assessments and analyses
Blood samples for PK analyses were collected pre-dose and at 30-min intervals for the first 5 h, and at regular intervals (1–24 h) up to 72 h after single-dose administration. Vericiguat plasma concentrations were determined after protein precipitation followed by liquid chromatography mass spectrometry with tandem mass spectrometric detection, with quantitation being achieved by weighted linear regression using stable isotope-labeled internal standards (Boettcher et al. 2021a). The determined analyte concentrations in study samples were verified by assaying quality control samples of blank matrix spiked with known concentrations of the respective analytes. Concentrations above the lower limit of quantification (LLOQ) were determined with a precision within 15% and an accuracy within 85–115%, and concentrations at the LLOQ were determined with a precision of 20% and an accuracy within 80–120%.
PK parameters were calculated with WinNonlin (versions 4.1a and 5.3, Pharsight Corporation, Mountain View, CA, USA) and included area under the curve (AUC), Cmax, and dose-normalized AUC and Cmax (AUC/D and Cmax/D, respectively).
For evaluation of absolute bioavailability, AUC/D and Cmax/D of vericiguat and 14C-labeled vericiguat, determined by noncompartmental analysis, were analyzed by analysis of variance (ANOVA) including treatment and subject effects. Point estimates (least squares means) and exploratory 90% confidence intervals (CIs) were calculated for ratios between treatments. The absolute bioavailability (F) of vericiguat was defined as the AUC/D ratio of 10 mg intact vericiguat tablets to 14C-labeled 20 μg vericiguat IV infusion.
To compare the different formulations and treatments, the parameters AUC/D and Cmax/D of vericiguat were analyzed using ANOVA including sequence, subject (sequence), period, and treatment effects. Bioequivalence was determined if 90% CIs for PK ratios for AUC and Cmax were within the limits of 0.80–1.25.
For the evaluation of dose proportionality of vericiguat, three different doses (2.5 mg, 5 mg, and 10 mg, with food) were evaluated with respect to their bioavailability. A mixed-effects power model (i.e., a linear regression between log-transformed AUC and Cmax and the logarithm of the dose) was used to assess dose proportionality (Sethuraman et al. 2007; Smith et al. 2000). The 90% CI acceptance range for dose proportionality was 84–116%.
Vericiguat PK results are presented from each study. Subjects with valid PK profiles for at least two treatments were included in the PK analyses. Study periods were considered invalid for PK analysis if pre-dose concentrations were larger than 5% of Cmax (Food and Drug Administration 2014), an invalid PK reading indicated that the subject had not ingested the tablet, or were deemed invalid due to a protocol deviation.
Safety results from the five studies were pooled. As part of the safety evaluation, blood pressure, heart rate, and electrocardiograms (ECGs) were recorded. The safety analysis set comprised all subjects who received the study drug.
In vitro studies
Vericiguat is a lipophilic (logP 2.99), weakly basic (pKa 4.19) compound. In line with its pKa value, solubility is pH-dependent. Solubility values were 0.9, 2, 26, and 247 mg/L in phosphate buffer pH 6.8, acetate buffer pH 4.5, glycine buffer pH 3, and HCl pH 2, respectively, resulting in dose/solubility ratios of 11,111 mL (pH 6.8), 5000 ml (pH 4.5), 385 mL (pH 3), and 40 mL (pH 2), respectively. Therefore, vericiguat is a low solubility compound according to the definition of the BCS.
Vericiguat showed a high permeability with Papp values of 111 ± 22 nm/s for the A-to-B direction and 464 ± 37 nm/s for the B-to-A direction across Caco-2 cells. Based on these data, an efflux ratio of 4.21 was calculated suggesting an active efflux.
Fed vs fasted
Dissolution of the intact vericiguat 10 mg tablet was increased in FeSSIF compared with FaSSIF (both 500 mL; Fig. 1). Similar results were observed for vericiguat 2.5 mg and 5 mg tablets (not shown).
Crushed vs intact tablet
Figure 2A, B and C shows the dissolution curves for vericiguat 10 mg of intact tablet and crushed tablet suspension applied to dissolution medium immediately after preparation, and crushed tablet suspension applied to dissolution medium 4 h after preparation. Individual data for each tablet are shown in Supplementary Tables S3, S4 and S5. With HCl pH 2 as dissolution medium, dissolution was complete in all cases. No relevant difference was detected between crushed and intact tablet formulations in the quality control medium. Comparison of the curves for crushed tablet suspension immediately and 4 h after preparation were similar, indicating that vericiguat was stable in crushed tablet suspension for 4 h at room temperature, and that no aggregation of suspended particles occurred during the storage time. As complete dissolution was observed (100% amount dissolved), no sample loss occurred during the procedure of crushing the tablet and transferring the crushed tablet into the vessel and thus, the subject in the respective clinical trial. Another concern of crushing the tablet is that crushing may potentially lead to faster dissolution due to higher surface area, and in consequence to faster absorption, which could translate into higher Cmax values. An even faster dissolution of crushed tablet versus intact tablet cannot be demonstrated in the acidic quality control medium because dissolution after 15 min was already complete for both crushed and intact tablets. Therefore, dissolution at higher pH was performed, using the media acetate buffer pH 4.5 and phosphate buffer pH 6.8, as recommended by various guidances on comparative in vitro dissolution testing, e.g., ICH M9 (International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) 2019). pKa- and pH-dependent solubility of vericiguat demonstrated a strong decrease in solubility between pH 2 and 3 (and further from 3 to 4.5 and 6.8), in line with the pKa value of ~ 4. In line with this, lower dissolution of vericiguat from tablets was observed in dissolution media acetate buffer pH 4.5 (Fig. 2B) and phosphate buffer pH 6.8 (Fig. 2C). However, no difference in dissolution between the intact tablet and crushed tablet suspension was observed at a higher pH, as indicated by pairwise F2 calculations (Table 3). In all cases, the F2 value was > 50. Furthermore, the in-use stability study of the crushed tablet suspension over 4 h at room temperature revealed no difference in dissolution at pH 4.5 and pH 6.8 (Table 3; Fig. 2B, C), as F2 values were > 50 in all cases.
Data are shown for the 10 mg tablet. Similar findings were observed for the 2.5 mg dose (not shown).
Phase I clinical studies
Across the five studies described here (Table 1), a total of 96 White males enrolled and completed treatment. The mean age of all subjects and mean BMI ranged from 28.1 to 38.5 years and 23.7 to 25.0 kg/m2, respectively, across studies. Five subjects withdrew from their respective studies early. Of these five subjects, two discontinued due to TEAEs (described below), one subject was withdrawn at the investigator’s decision due to the omission of a treatment period, another subject reported behavioral changes (that were considered not drug-related), and one was withdrawn due to a positive alcohol test.
Absolute and relative bioavailability
Under fed conditions, oral bioavailability of vericiguat was near complete, as vericiguat 10 mg (administered orally as two intact 5 mg tablets) followed by IV infusion of [14C] vericiguat 20 µg had an AUC/D relative to IV infusion of 93% (Table 4; Supplementary Figure S1 and S2).
In the fasted state, the relative bioavailability of 5 mg vericiguat was reduced following administration as intact tablets relative to the PEG solution (Supplementary Figure S3 and S4). The AUC of the tablet was 29% lower and the Cmax was 40% lower than the PEG solution. Oral administration of vericiguat 1.25 mg intact tablet showed similar bioavailability to the 5 mg PEG solution, based on dose-normalized exposure.
Effect of food
The effect of food on the PK of vericiguat indicated by the dissolution studies was confirmed in vivo. For both 5 mg and 10 mg vericiguat doses, administration of the intact vericiguat tablet with food increased median Tmax from 1.5–2.0 h (fasted) to 4.0–4.5 h (fed). At the 5 mg dose, vericiguat AUC and Cmax increased by 19% and 9%, respectively, with food relative to the fasted state and the 90% CIs were slightly above the upper limit for bioequivalence. The interindividual variability of PK parameters reduced when vericiguat 5 mg was administered with food: the coefficient of variation (CV) was 20–45% in the fasted state and < 20% with food.
At the 10 mg dose, AUC and Cmax were further increased by 44% and 41%, respectively, when administered with food (high-fat, high-calorie meal) compared with the fasted state, with 90% CIs above the limit of bioequivalence (Table 5; Supplementary Figure S5, S6, S7 and S8). AUC was 5600 µg*h/L and 3890 µg*h/L in the fed and fasted states, respectively. PK variability was reduced when vericiguat tablet was administered with food: the variability in exposure (AUC) was reduced to 19% from 41% and variability of Cmax was reduced to 16% from 60% relative to the fasted state.
Effect of type of food
The type of meal consumed had no effect on AUC/D, with the 90% CIs for AUC/D falling within the limits for bioequivalence. However, 90% CI for Cmax/D was above the upper limit. As this was only slightly over the upper limit and in line with the lower calorie count, and its lower effect on a delay of gastric emptying than a high calorie count, the increase in Cmax/D with a low-fat, low-calorie meal relative to a high-fat, high-calorie meal was not considered clinically relevant (Table 5; Supplementary Figure S9 and S10).
Overall, geometric mean AUC and Cmax increased with increasing vericiguat doses (Fig. 3). In the exploratory dose-proportionality study, exposure of vericiguat 1.25–10 mg administered in the fed state increased in a dose-proportional manner. Further investigation on the pivotal food effect and dose proportionality study confirmed vericiguat PK was dose-proportional when taken with food. The point estimates for the slope of the linear regression between log-transformed AUC and Cmax, respectively, and the logarithm of the dose (β) and the associated 90% CIs (Sethuraman et al. 2007; Smith et al. 2000) were within the acceptance range of 84–116% for dose proportionality (AUC: 100.8% [90% CI 94.1–107.5%]; Cmax: 97.8% [90% CI 91.8–103.8%].
Effects of administering vericiguat as a crushed tablet suspension relative to intact tablets
Findings from dissolution studies, which showed no differences between the formulations, were confirmed with in vivo studies. Plasma concentrations of vericiguat after administration of 10 mg crushed tablet suspension and 10 mg intact tablet with food are shown in Supplementary Figure S9 and S10. The relative bioavailability of vericiguat 10 mg as a crushed tablet suspension with respect to AUC and Cmax was equivalent to intact tablets (with food), as demonstrated by ANOVA. The point estimates for the ratios of AUC/D and Cmax/D were near unity (Fig. 4A, B) and exploratory 90% CIs were within the limits for bioequivalence (Table 6).
A pooled analysis of all four formulations of vericiguat up to 10 mg in 102 healthy subjects demonstrated that vericiguat was generally well-tolerated. No deaths or serious adverse events occurred. Of the two subjects who discontinued due to TEAEs, one was due to a TEAE of common cold, considered unrelated to the study drug, and the other subject was due to events of rash and pruritus, which were mild in intensity and judged by the investigator as related to vericiguat. No trends in the incidence of drug-related adverse events (AEs) were observed across any of the vericiguat formulations tested (14.8–24.7% for vericiguat up to 10 mg).
In total, 74 (72.5%) subjects experienced at least one TEAE. No TEAEs of severe intensity were reported.
The effects of vericiguat on vital signs, ECG, and laboratory test findings were consistent with the mode of action of vericiguat, and in line with the formulations tested.
Vericiguat showed a typical biopharmaceutical profile for a BCS class II drug. The biopharmaceutical properties of different doses and formulations of vericiguat were characterized and included an evaluation of the bioavailability, impact of crushing the tablet, dose proportionality, and the effects of food on the PK profile of vericiguat, as well as an assessment of the effects of ingesting different meal types before receiving vericiguat.
We demonstrated that the absolute bioavailability of vericiguat administered as intact tablets relative to the IV formulation was high at 93% under fed conditions. Furthermore, the relative bioavailability assessments demonstrated that vericiguat administered as intact tablets resulted in delayed vericiguat absorption relative to the PEG solution formulation.
In biorelevant media, dissolution of the intact vericiguat tablet was increased in FeSSIF compared with FaSSIF, indicating a higher rate of vericiguat solution formation in the fed state relative to the fasted state (Fig. 1). In line with dissolution data, the effect of food on the PK of vericiguat was confirmed in vivo. Ingestion of the tablet with food reduced PK variability and increased vericiguat exposure compared with the fasted state.
With poorly soluble weak bases, the question of whether an increase in gastric pH after food intake (Koziolek et al. 2015a, 2015b) may decrease dissolution in the stomach resulting in a potential negative food effect must be considered. Alternatively, bile salts, lecithin, and food components may promote formulation and active pharmaceutical ingredient (API) wettening and dissolution, resulting in a positive food effect. As suggested by in vitro dissolution experiments in FaSSIF and FeSSIF (Fig. 1), the increased bioavailability of vericiguat after administration with food was likely due to improved solubility and dissolution due to bile salts and food components enhancing wettability and, therefore, improved absorption (Boettcher et al. 2021a). In a separate study (data not shown), dissolution of vericiguat tablets was recorded in a two-stage biorelevant dissolution model (slightly adapted from Mann et al. (Mann et al. 2017)) that represents gastric to intestinal transfer. Data revealed that under simulated fed conditions (stomach: 250 mL of fasted-state simulated gastric fluid (FaSSGF) adjusted to pH 4.0, dissolution recorded for 30 min; after 30 min 250 mL of a double concentrated FeSSIF was added to reach FeSSIF of pH 5.0, dissolution recorded for another 150 min), up to approximately 10% amount of API dissolved was observed in FaSSGF adjusted to pH 4.0. After addition of 250 mL of the double-concentrated FeSSIF, the dissolution curves in the resulting 500 mL of FeSSIF pH 5.0 were very similar to dissolution curves obtained in FeSSIF without the prior exposure of the tablets to FaSSGF pH 4.0. The presence of food also leads to a physiological effect whereby gastric emptying is delayed. This effect increased with an increasing amount of calorie intake. In line with this, a prolonged median Tmax of the intact tablet demonstrated a delayed absorption in the fed state relative to the fasted state.
A limitation of dissolution studies in one-compartment dissolution systems is that they do not investigate complex mechanistic processes such as gastric emptying, potential vericiguat precipitation, and re-dissolution in the small intestine of vericiguat already dissolved in the stomach. Further investigation would be required to determine these processes. For example, data obtained from in vitro set-ups, in turn, can be used to inform a respective physiologically-based PK (PBPK) model (Kambayashi et al. 2016; Ruff et al. 2017; Pathak et al. 2017; Kourentas et al. 2016; Hens et al. 2017). A verified PBPK model of vericiguat and its major metabolite, M-1, has been developed based on in vitro and clinical PK data to provide a quantitative understanding of the disposition pathways and PK in healthy adults (Frechen et al. 2020). Vericiguat could be tested in a human in vivo aspiration study, in which real-time dissolution and precipitation are measured in the stomach and small intestine by tube sampling after oral administration of respective formulations. Such studies have been performed for other poorly soluble weak bases such as dipyridamole, ketoconazole (Psachoulias et al. 2011) and posaconazole (Hens et al. 2016a, 2016b), and have been used as a backbone to calibrate in vitro multicompartment dissolution/precipitation set-ups. However, these types of investigations are beyond the scope of this article, but certainly of interest for the future.
As the calories of a meal can cause physiological gastrointestinal changes that affect systemic availability of a drug, we investigated two meal types (high-fat, high-calorie or low-fat, low-calorie), in accordance with guidelines (Food and Drug Administration 2019). The type of meal did not seem to have a clinically meaningful effect on the PK profile of vericiguat. Over the dose range studied, vericiguat had linear PK, demonstrating dose proportionality, consistent with previous studies (Boettcher et al. 2019). For BCS class II compounds, food effect is driven by bile salt solubilization, a response to the fat content often anticipated due to an increase in bile micelle concentrations. The lack of a meal-type effect for vericiguat supports the reasoning that for some BCS class II compounds the in vivo solubilization effect can be maximized with lower-fat-content meals compared with the standard meal commonly used in food effect studies or points to additional mechanisms, such as improved wetting facilitating dissolution, which may not require a large bile salt concentration.
In vitro dissolution studies also allowed a direct comparison between crushed versus intact tablets and complemented the respective clinical evaluations of the formulations. The dissolution study demonstrated that no vericiguat was lost during crushing and harvesting the crushed tablet, and that dissolution of the crushed tablet was not impaired by aggregation of the crushed tablet particles during the in-use stability study at room temperature. Furthermore, crushing the tablet did not increase the dissolution when compared with intact tablet, as indicated by comparative dissolution data in acetate buffer pH 4.5 and phosphate buffer pH 6.8. These in vitro dissolution data in media listed in the various bioequivalence guidelines (e.g., ICH M9 (International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) 2019)) reinforce the relevance of these in vitro dissolution media and conditions for the in vivo biopharmaceutical performance when it comes to formulation comparison.
Consistent findings were observed in in vivo studies, which demonstrated that systemic exposure or absorption (AUC and Cmax) of vericiguat was comparable following administration of crushed tablet suspension and intact tablets in healthy subjects. One may speculate that there may be a difference in the rate of gastric emptying of vericiguat between intact and crushed tablets due to the magenstraße (stomach road) (Pal et al. 2007; Kiyota et al. 2022; Grimm et al. 2017), a normal physiological mechanism by which co-ordinated contraction waves move liquid content along a narrow path through the stomach to the duodenum (Pal et al. 2007). Faster gastric emptying of dissolved and finely dispersed drug may lead to earlier onset of peak plasma concentrations with the crushed tablet suspension. However, given that there were no relevant effects of crushing the tablet on Cmax, it is unlikely that gastric emptying of vericiguat differed significantly between the intact tablet and crushed tablet suspension. Therefore, concerns that the administration of vericiguat as a crushed tablet suspension may alter systemic absorption were addressed here. These findings support the use of vericiguat in crushed tablet suspension as a viable method of administration and provide clinicians with an additional treatment option to administer vericiguat to very ill patients, or those with dysphagia, who are unable to swallow whole tablets.
Vericiguat was generally well-tolerated across the five phase I studies. The types of AE reported were consistent with the mode of action of vericiguat and no trends in the incidence of drug-related AEs were observed between vericiguat formulations. These data demonstrate that administration of vericiguat as an intact tablet or as a crushed tablet suspension was generally well-tolerated, with an acceptable safety profile.
The interpretation of the study results is potentially limited by missing data. Subjects were excluded from the analysis, in accordance with a standardized GCP-conformed process, if they had a study period that was invalid for PK analysis. Individual PK samples were excluded if they were damaged in transport. Missing data were not replaced; however, missing data were predicted and accounted for in the determination of sample size to ensure adequate statistical power for the analyses in those studies that were powered.
Oral bioavailability of vericiguat was near complete following administration of the intact tablet under fed conditions, and vericiguat PKs were dose-proportional when taken with food. Ingestion of the intact vericiguat tablet with food increased vericiguat exposure and reduced PK variability compared with the fasted state. Meal type had no clinically relevant effect on vericiguat exposure.
No relevant difference was detected between crushed and intact tablet formulations in in vitro dissolution studies, and phase I studies demonstrated that, in the fed state, the relative bioavailability of vericiguat crushed tablets was equivalent to intact tablets. Vericiguat was stable in crushed tablet suspension for 4 h at room temperature.
Vericiguat was generally well-tolerated, with an AE profile consistent with its mode of action.
Overall, the findings from the in vitro and phase I studies presented here provided the basis for the dosing recommendation to administer vericiguat with food in the SOCRATES-REDUCED (Gheorghiade et al. 2015) and VICTORIA (Armstrong et al. 2020) studies, irrespective of meal type. These results also provide important guidance on the potential for administering vericiguat in crushed tablet formulation.
Active pharmaceutical ingredient
Area under the curve
Analysis of variance
Biopharmaceutics Classification System
Body mass index
- C max :
Maximum plasma concentration
- C max/D:
Coefficient of variation
Fasted-state simulated intestinal fluid
Fasted-state simulated gastric fluid
Fed-state simulated intestinal fluid
Treatment-emergent adverse events
Time to reach Cmax
Food and Drug Administration. M9 Biopharmaceutics classification system-based biowaivers. 2021b. https://www.fda.gov/media/148472/download. Accessed 2 Mar 2022
Armstrong PW, Pieske B, Anstrom KJ, Ezekowitz J, Hernandez AF, Butler J et al (2020) Vericiguat in patients with heart failure and reduced ejection fraction. N Engl J Med 382:1883–1893
Becker C, Boettcher M, Loewen S, Mueck W. Biopharmaceutical profile, bioavailability, food effect, and pharmacokinetics of vericiguat: a novel soluble guanylate cyclase stimulator. The American Association of Pharmaceutical Scientists (AAPS); 2019 November 3–6, 2019; San Antonio, TX. Abstract M1430 - 13 - 86. https://www.eventscribe.com/2019/PharmSci360/fsPopup.asp?efp=SUlFUEhHSFQ4MDkx&PosterID=235054&rnd=0.5702747&mode=posterinfo. Accessed 10 Oct 2022
Boettcher M-F, Thomas D, Mueck W, Loewen S, Arens E, Yoshikawa K et al (2019) Safety, pharmacodynamic and pharmacokinetic characterisation of vericiguat: key results from six phase I studies in healthy subjects. Eur J Clin Pharmacol 21(Suppl S1):293
Boettcher M, Gerisch M, Lobmeyer M, Besche N, Thomas D, Gerrits M et al (2020) Metabolism and pharmacokinetic drug-drug interaction profile of vericiguat, a soluble guanylate cyclase stimulator: results from preclinical and phase I healthy volunteer studies. Clin Pharmacokinet 59:1407–1418
Boettcher M, Thomas D, Mueck W, Loewen S, Arens E, Yoshikawa K et al (2021a) Safety, pharmacodynamic, and pharmacokinetic characterization of vericiguat: results from six phase I studies in healthy subjects. Eur J Clin Pharmacol. https://doi.org/10.1007/s00228-020-03023-7:527-37
Boettcher M, Loewen S, Gerrits M, Becker C (2021b) Pharmacodynamic and pharmacokinetic interaction profile of vericiguat: Results from three randomized phase I studies in healthy volunteers. Clin Pharmacokinet 60:337–351
European Medicines Agency. VerquvoTM Summary of Product Characteristics. 2021. https://www.ema.europa.eu/en/documents/product-information/verquvo-epar-product-information_en.pdf. Accessed 11 May 2022
Food and Drug Administration. Food-effect bioavailability and fed bioequivalence studies. 2002. https://www.fda.gov/regulatory-information/search-fda-guidance-documents/food-effect-bioavailability-and-fed-bioequivalence-studies. Accessed 11 May 2022
Food and Drug Administration. Guidance for industry. Bioavailability and bioequivalence studies submitted in NDAs or INDs — general considerations. 2014. https://www.fda.gov/media/88254/download. Accessed 11 May 2022
Food and Drug Administration. Waiver of in vivo bioavailability and bioequivalence studies for immediate-release solid oral dosage forms based on a biopharmaceutics classification system. 2017. https://www.gmp-compliance.org/files/guidemgr/UCM070246.pdf. Accessed 11 May 2022
Food and Drug Administration. Use of liquids and/or soft foods as vehicles for drug administration: General considerations for selection and in vitro methods for product quality assessments - Guidance for Industry. 2018. https://www.fda.gov/media/114872/download. Accessed 11 May 2022
Food and Drug Administration. Assessing the effects of food on drugs in INDs and NDAs — clinical pharmacology considerations guidance for industry. 2019. https://www.fda.gov/regulatory-information/search-fda-guidance-documents/assessing-effects-food-drugs-inds-and-ndas-clinical-pharmacology-considerations. Accessed 11 May 2022
Food and Drug Administration. VerquvoTM (vericiguat) tablets. Highlights of prescribing information. 2021a. https://www.accessdata.fda.gov/drugsatfda_docs/label/2021/214377s000lbl.pdf. Accessed 11 May 2022.
Frechen S, Ince I, Dallmann A, Gerisch M, Jungmann N, Becker C, et al. (2020) Physiologically-based pharmacokinetic (PBPK) exploration of extrinsic factors influencing vericiguat pharmacokinetics. Eur Heart J 41(Suppl 2):ehaa946.3329
Gheorghiade M, Greene SJ, Butler J et al (2015) Effect of vericiguat, a soluble guanylate cyclase stimulator, on natriuretic peptide levels in patients with worsening chronic heart failure and reduced ejection fraction: the SOCRATES-REDUCED randomized trial. J Am Med Assoc 314:2251–2262
Grimm M, Scholz E, Koziolek M, Kuhn JP, Weitschies W (2017) Gastric water emptying under fed state clinical trial conditions is as fast as under fasted conditions. Mol Pharm 14:4262–4271
Hens B, Brouwers J, Corsetti M, Augustijns P (2016a) Supersaturation and precipitation of posaconazole upon entry in the upper small intestine in humans. J Pharm Sci 105:2677–2684
Hens B, Corsetti M, Brouwers J, Augustijns P (2016b) Gastrointestinal and systemic monitoring of posaconazole in humans after fasted and fed state administration of a solid dispersion. J Pharm Sci 105:2904–2912
Hens B, Tsume Y, Bermejo M, Paixao P, Koenigsknecht MJ, Baker JR et al (2017) Low buffer capacity and alternating motility along the human gastrointestinal tract: implications for in vivo dissolution and absorption of ionizable drugs. Mol Pharm 14:4281–4294
International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH). Guideline M9: Biopharmaceutics classification system-based biowaivers. 2019. https://database.ich.org/sites/default/files/M9_Guideline_Step4_2019_1116.pdf. Accessed 2 Mar 2022
Kambayashi A, Yasuji T, Dressman JB (2016) Prediction of the precipitation profiles of weak base drugs in the small intestine using a simplified transfer (“dumping”) model coupled with in silico modeling and simulation approach. Eur J Pharm Biopharm 103:95–103
Kiyota T, Kambayashi A, Takagi T, Yamashita S (2022) Importance of gastric secretion and the rapid gastric emptying of ingested water along the lesser curvature (“Magenstrasse”) in predicting the in vivo performance of liquid oral dosage forms in the fed state using a modeling and simulation. Mol Pharm 19:642–653
Kourentas A, Vertzoni M, Symillides M, Hens B, Brouwers J, Augustijns P et al (2016) In vitro evaluation of the impact of gastrointestinal transfer on luminal performance of commercially available products of posaconazole and itraconazole using BioGIT. Int J Pharm 515:352–358
Koziolek M, Schneider F, Grimm M, Modebeta C, Seekamp A, Roustom T et al (2015a) Intragastric pH and pressure profiles after intake of the high-caloric, high-fat meal as used for food effect studies. J Control Release 220:71–78
Koziolek M, Grimm M, Becker D, Iordanov V, Zou H, Shimizu J et al (2015b) Investigation of pH and temperature profiles in the GI tract of fasted human subjects using the Intellicap((R)) system. J Pharm Sci 104:2855–2863
Mann J, Dressman J, Rosenblatt K, Ashworth L, Muenster U, Frank K et al (2017) Validation of dissolution testing with biorelevant media: an OrBiTo study. Mol Pharm 14:4192–4201
Moore JW, Flanner HH (1996) Mathematical comparison of curves with an emphasis on in vitro dissolution profiles. Pharm Tech 20:64–74
Pal A, Brasseur JG, Abrahamsson B (2007) A stomach road or “Magenstrasse” for gastric emptying. J Biomech 40:1202–1210
Pathak SM, Ruff A, Kostewicz ES, Patel N, Turner DB, Jamei M (2017) Model-based analysis of biopharmaceutic experiments to improve mechanistic oral absorption modeling: an integrated in vitro in vivo extrapolation perspective using ketoconazole as a model drug. Mol Pharm 14:4305–4320
Psachoulias D, Vertzoni M, Goumas K, Kalioras V, Beato S, Butler J et al (2011) Precipitation in and supersaturation of contents of the upper small intestine after administration of two weak bases to fasted adults. Pharm Res 28:3145–3158
Ruff A, Fiolka T, Kostewicz ES (2017) Prediction of Ketoconazole absorption using an updated in vitro transfer model coupled to physiologically based pharmacokinetic modelling. Eur J Pharm Sci 100:42–55
Sethuraman VS, Leonov S, Squassante L, Mitchell TR, Hale MD (2007) Sample size calculation for the power model for dose proportionality studies. Pharm Stat 6:35–41
Smith BP, Vandenhende FR, DeSante KA, Farid NA, Welch PA, Callaghan JT et al (2000) Confidence interval criteria for assessment of dose proportionality. Pharm Res 17:1278–1283
Wunder F, Gnoth MJ, Geerts A, Barufe D (2009) A novel PDE2A reporter cell line: characterization of the cellular activity of PDE inhibitors. Mol Pharm 6:326–336
The authors would like to thank the healthy subjects and study site personnel involved in these studies. Medical writing support was provided by Laila Guzadhur, PhD, of Scion, London, UK, supported by Bayer and Merck Sharp & Dohme LLC, a subsidiary of Merck & Co., Inc., Rahway, NJ, USA according to Good Publication Practice guidelines (https://www.acpjournals.org/doi/10.7326/M15-0288). The Sponsor was involved in the study design, collection, analysis, and interpretation of data, as well as data checking of information provided in the manuscript. However, ultimate responsibility for opinions, conclusions and data interpretation lies with the authors.
Clinical trial registry data
16 December 2011
30 March 2012
08 January 2013
13 February 2013
07 October 2015
28 October 2015
21 June 2016
13 October 2016
16 May 2017
29 August 2017
Funding for this research was provided by Bayer AG, Berlin, Germany, and Merck Sharp & Dohme LLC, a subsidiary of Merck & Co., Inc., Rahway, NJ, USA.
W. Mueck, U. Muenster, and C. Becker are employees of Bayer AG and may own stock in the company. M. Lobmeyer and M. Boettcher are former employees of Bayer AG and may own stock in the company. S. Loewen is an employee of Chrestos Concept GmbH & Co. KG, which received funding for this analysis from Bayer AG.
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Vericiguat formulations administered within the clinical development program. Table S2. HPLC conditions for determination of vericiguat content in filtrate in dissolution studies. Table S3. Dissolution of vericiguat 10 mg as an intact tablet, crushed tablet suspension immediately after preparation, and as a crushed tablet suspension 4 h after preparation in 900 mL 0.01M HCl pH 2 at 37°C at 75 rpm. Table S4. Dissolution of vericiguat 10 mg as an intact tablet, crushed tablet suspension immediately after preparation, and as a crushed tablet suspension 4 h after preparation in 900 mL acetate buffer pH 4.5 at 37°C at 75 rpm. Table S5. Dissolution of vericiguat 10 mg as an intact tablet, crushed tablet suspension immediately after preparation, and as a crushed tablet suspension 4 h after preparation in 900 mL acetate buffer pH 6.8 at 37°C at 75 rpm. Figure S1. Mean (standard deviation) plasma concentrations of vericiguat (µg/L) after a single dose of vericiguat (intact tablet 10 mg) followed by a single 30-min intravenous infusion of 20 μg 14C-labeled vericiguat starting 4 h after oral vericiguat dosing (n = 10). Figure S2. Individual plasma concentrations of vericiguat (µg/L) after a single dose of vericiguat (intact tablet 10 mg) followed by a single 30-min intravenous infusion of 20 μg 14C-labeled vericiguat starting 4 h after oral vericiguat dosing (n = 10). Figure S3. Mean (standard deviation) plasma concentrations of vericiguat (µg/L) (dose normalized) after a single dose of vericiguat (intact tablet [fed and fasted] and PEG solution [fasted]), n = 15. Figure S4. Individual plasma concentrations of vericiguat (µg/L) after a single dose of vericiguat (n = 15) (A) 1.25 mg intact tablet fasted, (B) 5 mg intact tablet fasted, (C) 5 mg PEG solution fasted, (D) 5 mg intact tablet fed. Figure S5. Mean (standard deviation) plasma concentrations of vericiguat (µg/L) after a single dose of vericiguat (intact tablets [fed], n = 13). Figure S6. Individual plasma concentrations of vericiguat (µg/L) after a single dose of vericiguat (intact tablets [fed and fasted], n = 13). (A) 1.25 mg intact tablet fed, (B) 2.5 mg intact tablet fed, (C) 5 mg intact tablet fed, (D) 10 mg intact tablet fed. Figure S7. Mean (standard deviation) plasma concentrations of vericiguat (µg/L) after a single dose of vericiguat (intact tablet [fed and fasted], n = 29). Figure S8. Individual plasma concentrations of vericiguat (µg/L) after a single dose of vericiguat (A) 2.5 mg fed, (B) 5 mg fed, (C) 10 mg fed, (D) 10 mg fasted. Figure S9. Mean plasma concentrations of vericiguat (µg/L) after a single dose of vericiguat (intact tablet and crushed tablet, n = 29). Figure S10. Individual plasma concentrations of vericiguat (µg/L) after a single dose of vericiguat 10 mg (intact tablet and crushed tablet formulations, n = 29) (A) crushed tablet high-fat, high-calorie meal, (B) intact tablet high-fat, high-calorie meal, (C) intact tablet low-fat, low-calorie meal.
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Becker, C., Boettcher, M., Muenster, U. et al. Results from in vitro and in vivo studies evaluating the bioavailability, effects of food, and administration as crushed tablet suspension on vericiguat pharmacokinetics. AAPS Open 8, 16 (2022). https://doi.org/10.1186/s41120-022-00063-4