Pharmacokinetics, safety of a single dose and multiple doses of voriconazole injection of two formulations, in Chinese healthy volunteers

Abstract

Voriconazole is a first-line medicine for treating invasive fungal infections. We evaluated the pharmacokinetics (PK) and safety of single/multiple doses of voriconazole injection of Hailing Pharmaceutical Group (Test, T), an imitation of Vfend® (Reference, R). Healthy subjects (n = 36) randomly received a once-daily dose of T or R 3 or 4 mg/kg on Day 1 (single dose), a once-daily dose of T or R 6 mg/kg on Day 4, and then six consecutive days for twice-daily doses of T or R 3 or 4 mg/kg (multiple doses). The plasma was collected up to 72 h at time points after dosing on Day 1/10. Samples were measured by the liquid chromatography tandem mass spectrometry method. PK parameters were confirmed according to a non-compartmental model. The relationship between the PK profiles of T and R revealed the different behavior in 3- and 4-mg/kg groups. After single/multiple doses in the 3-mg/kg group, the mean value for the area under the plasma concentration–time curve (AUC_0−t, AUC_0−∞) of R is about twice T. However, there was a high degree of similarity in the 4-mg/kg group. The maximum plasma concentration (C_max) of T and R showed no noticeable difference in the two groups. The median T_max of T and R were within 2.0–2.13 h in the 3-mg/kg group and 2.0–2.17 h in the 4-mg/kg group. Severe adverse events did not occur. No clinically significant differences were found in safety and tolerance between T and R. This clinical study indicated that voriconazole injection might provide a safer alternative medicine.

INTRODUCTION

In recent years, the incidence of fungal infections has increased significantly with the influence of broad-spectrum antibiotics, chemotherapy drugs, immunosuppressants, AIDS, radiotherapy, and organ transplantation. Fungal infections are a severe threat to human health, especially invasive fungal infections (IFIs), which make them hard to treat.¹ Currently, azoles, echinocandins, polyenes, and pyrimidine analogs are still the most commonly used antifungal drugs for the treatment of IFIs in the clinic.²

Voriconazole is triazole as a first-line medicine for treating IFIs.³ Since Pfizer Company developed it in 2002, it is preferred for patients with more serious illnesses or intra-cavitary fungal infections.⁴ Specifically, it is recommended to treat invasive aspergillosis, candidemia, disseminated infections that are caused by Candida species, and esophageal candidiasis in adults.⁵ Voriconazole can inhibit the fungal cytochrome P450 (CYP) enzyme lanosterol 14-α-demethylase and reduce ergosterol synthesis, an essential component of fungal cell membranes.^6,7 Voriconazole is mainly metabolized by the CYP2C19 enzyme in the liver, and CYP2C9 and CYP3A4 are secondary metabolic enzymes.⁸

Voriconazole injection of Hailing Pharmaceutical Group has achieved a breakthrough in improving the solubility of voriconazole with different excipients for the first time in China. Voriconazole (Vfend®, Pfizer) is available in a various types, and a 200 mg powder for infusion is used in this trial. Hailing Pharmaceutical developed the voriconazole 200 mg powder for infusion, an imitation of the original drug. Nevertheless, Hailing Pharmaceutical is not in the market yet in China. Our study designed the 3 and 4 mg/kg of voriconazole injection groups. Through the phase I clinical study, the primary objectives were to assess the pharmacokinetics (PK) of Hailing Pharmaceutical and Vfend®. Moreover, the secondary objectives were to evaluate the safety of the T and R formulations in Chinese HVs. At the single-dose phase, we could find out PK metabolism behavior, obtain PK parameters of single-dose, and explore the relationship of dose exposure. A multiple-dose escalation PK study was carried out based on a single-dose escalation PK study to explore the PK metabolism behavior of continuous multiple doses and understand the characteristics of accumulation and fluctuation in vivo. The pharmacokinetics data from these single/multiple doses studies are presented here. Currently, the recommended voriconazole dose is 6 mg/kg in the clinic. The purpose of designing the low concentration is to provide certain data for the bioequivalence (BE) test subsequently on the dosage choice.

MATERIALS AND METHODS Study design

The PK comparison study of voriconazole for injection was a single-center, randomized, open-label, positive drug control, single/multiple-dose, and parallel-design: a 3-mg/kg group (n = 18) and a 4-mg/kg group (n = 18). Each group contained 18 HVs, and they were randomly given voriconazole injection produced by Hainan Hailing Pharmaceutical, Hainan, China (n = 9) or Vfend® (n = 9) intravenously for 120 ± 5 min. Thirty-six HVs received voriconazole intravenously in two formulations simultaneously. On Day 1, a dose of T (3 or 4 mg/kg) or R (3 or 4 mg/kg) was given intravenously. On Day 4, twice-daily doses of T or R (6 mg/kg) were given intravenously. From Day 5–10, subjects were administered twice-daily IV doses of T (3 or 4 mg/kg) or R (3 or 4 mg/kg). Then, the blood samples were collected from D1/D10 for 72 h; the specific administration plans are shown in Figure 1.

Inclusion criteria

The inclusion criteria were as follows: (1) healthy volunteers (HVs) of either gender and appropriate sex ratio, age between 18 and 45 years old, weight ≥50 kg, body mass index (BMI) range from 19.0 to 26.0; (2) subjects were informed of the lab process and possible adverse events (AEs); (3) acted as subjects voluntarily and had signed the informed consent before the studies; (4) not pregnant during the study or using any contraceptives within 6 months; and (5) subjects understand and comply with the requirements of this trial.

Exclusion criteria

The exclusion criteria were as follows: (1) subjects were allergic to triazoles, their excipients, or other drugs; (2) subjects had any chronic or serious illness that might affect the results of the study; (3) subjects had needle sickness or blood sickness in history; (4) subjects received vaccination within 3 months before the administration; (5) subjects with clinically significant abnormality from laboratory tests or specialist examination, such as an electrocardiogram: male ≥ 450 ms or female ≥ 460 ms; (6) subjects had used any kinds of drugs within 2 weeks before the test; (7) subjects had participated in another clinical trial within 3 months; (8) subjects had a history of intemperance, heavy smoking, or excessive intake of caffeine in the last 3 months; (9) subjects underwent surgery within 30 days or will plan to have surgery during the study period; and (10) subjects deemed unsuitable for inclusion for other reasons.

Eligible volunteers of the PK comparison study were required to stay in Phase I Clinical Research Center for 1 day before agent administration and stay 13 days until finished. The subjects had a formal dinner before drug administration, and they were required to be fasting after 22:00.

PK assessment

During the PK comparison study, blood samples were collected from Chinese HVs to measure the level of voriconazole after given agents intravenously at D1/D10 at the following time points: 0, 0.25, 0.50, 1.00, 1 h 20 min, 1 h 40 min, 2.00, 2 h 10 min, 2 h 20 min, 2 h 30 min, 2 h 45 min, 3.00, 4.00, 6.00, 8.00, 12.00, 24.00, 36.00, 48.00, and 72.00 h. The first 1 ml of blood was discarded, and then 4 ml of blood samples were collected and stored in K2-ethylenediaminetetraacetic acid tubes. All samples were allowed to centrifuge at 2000g and stand at 4°C for 10 min, and then each sample was separated into two polypropylene tubes. Finally, tubes were stored at −70°C for future analysis.

Safety assessment

Safety assessment was an index used to evaluate the variation after giving voriconazole intravenously, and assessed items included clinical symptoms, laboratory evaluation, AEs, 12-lead electrocardiography, and vital signs (temperature, body pressure, and heart rate). The AE evaluation indicators were clinical signs, severity, duration, therapeutic measures, and prognosis. And, the correlation between the AEs and drug dosage was explored.

PK and statistical analysis

A non-compartmental model on Phoenix WinNonlin 8.2 (Certara, Princeton, NJ, USA) was used to calculate the analysis of the PK parameters for the study. Statistical analysis was performed with SAS 9.4 Statistical Package (Cary, NC, USA).

The PK parameters for the PK comparison study in single-dose steady-state included maximum plasma concentration (C_max), time to C_max (T_max), the terminal elimination half-life (t_1/2), area under the plasma concentration-time curve (AUC), AUC from time 0 to t quantifiable sampling point (AUC_0−t), AUC from time zero to infinity (AUC_0−∞), apparent clearance rate (CL/F), and elimination rate constant (V_Z/F). The PK parameters for the PK comparison study in multiple doses were peak concentration at steady state (C_max,ss), time to reach peak serum concentration at constant state (T_max,ss), t_1/2, V_Z/F, apparent clearance (CL_ss), average steady-state concentration (C_av,ss), R_AUC, R_Cmax, AUC_tau. The units of data were consistent between PK parameters and the test data.

Liquid chromatography–tandem mass spectrometry

The plasma concentration of voriconazole was measured by using an Agilent 1200 high-performance liquid chromatography system from Agilent Technologies and API 4000™ from AB Sciex. Voriconazole and ketoconazole (internal standards, IS) were purchased from the Hainan Hailing Pharmaceutical Group, and the purity of both chemicals was above 98%. Acetonitrile and methanol belonged to Fisher Scientific. The other reagents were all of the analytical grades. Chromatographic separation was achieved on an Xbridege-C19 column (3.5 μm, 4.6 × 100 mm) from waters at a column temperature of 40°C. Voriconazole and IS were extracted from serum by protein precipitation. They were diluted with the mobile phase (solvent A), which was 1 mg/L sodium acetate in ultra-pure water containing 0.01% formic acid, and the organic phase (solvent B) was acetonitrile. The total running time was 9 min and delivered at 0.3 ml/min. Calibration standards and control samples were used in each experiment for quality control. In positive ion mode, the mass spectrometer was performed, and the mass transition pairs were m/z 350.3 → 281.1 for voriconazole and m/z 531.3 → 82.0 for ketoconazole (IS). The PK analyses and statistical analyses were measured.

RESULTS Characteristics of HVs at baseline

Thirty-six HVs were enrolled in the PK comparison study. We collected the baseline characteristics and demographics of all subjects in Table 1. The mean age was 29.44 ± 5.87 years, and the mean weight was 64.78 ± 7.85 kg in the 3-mg/kg group. The mean age and weight were 28.83 ± 7.46 years and 62.93 ± 8.21 kg, respectively, in the 4-mg/kg group.

TABLE 1 Baseline demographic characteristics (mean ± standard deviation) of HVs

	3 mg/kg			4 mg/kg
	T (n = 9)	R (n = 9)	ALL (n = 18)	T (n = 9)	R (n = 9)	ALL (n = 18)
Sex, n (%)
Male	7 (77.8)	6 (66.7)	13 (72.2)	8 (88.9)	6 (66.7)	14 (77.8)
Female	2 (22.2)	3 (33.3)	5 (27.8)	1 (11.1)	3 (33.3)	4 (22.2)
Age	28.11 ± 6.66	30.78 ± 4.99	29.44 ± 5.87	24.44 ± 3.88	33.22 ± 7.74	28.83 ± 7.46
Weight (kg)	67.84 ± 6.32	61.71 ± 8.36	64.78 ± 7.85	63.79 ± 6.45	62.08 ± 10.00	62.93 ± 8.21
Height (cm)	169.06 ± 8.81	162.78 ± 7.01	165.92 ± 8.37	169.56 ± 5.72	164.33 ± 10.61	166.94 ± 8.70
BMI (kg/m2)	23.74 ± 1.30	23.20 ± 1.69	23.47 ± 1.49	22.14 ± 1.44	22.87 ± 1.60	22.51 ± 1.52

Plasma concentration–time profiles

PK parameters of each administration group were analyzed by testing plasma concentration. The mean plasma concentration–time profile and the semi-logarithm of voriconazole were illustrated in Figure 2. The trend of C_max and AUC of T and R formulations was consistent with the increasing dose both in the 3- and 4-mg/kg groups.

Single-dose PK of voriconazole: The plasma concentration of voriconazole in the 3-mg/kg group achieved a C_max of 1471.11 ± 227.68 (ng/ml) at 2.00 (median) after giving T and 1443.33 ± 449.58 (ng/ml) at 2.00 h (median) after giving R. In the 4-mg/kg group, C_max was 2150.00 ± 340.81 (ng/ml) at 2.17 h (median) after giving T and 2356.67 ± 251.15 (ng/ml) at 2.00 h (median) after giving R. The mean of t_1/2 arrived at 6.27 ± 1.12 h of T in the 3-mg/kg group, 7.75 ± 4.62 h of R in the 3-mg/kg group, 6.18 ± 1.04 h of T in the 4-mg/kg group, and 6.66 ± 0.81 h of R in the 4-mg/kg group. They are illustrated in Figure 2A,C.

Multiple-dose PK of voriconazole: The plasma concentration of voriconazole in the 3-mg/kg group achieved a C_max,ss of 3735.56 ± 1465.28 (ng/ml) at 2.13 (median) after giving T and 4792.22 ± 2430.12 (ng/ml) at 2.11 h (median) after giving R. In the 4-mg/kg group, C_max was 6752.22 ± 2128.90 (ng/ml) at 2.04 (median) after giving T and 6415.71 ± 1770.92 (ng/ml) at 2.07 h (median) after giving R. The mean of t_1/2 arrived at 9.25 ± 4.52 h of T in the 3-mg/kg group, 14.08 ± 12.3 h of R in the 3-mg/kg group, 11.71 ± 8.43 h of T in the 4-mg/kg group, and 11.26 ± 4.9 h of R in the 4-mg/kg group. The results are illustrated in Figure 2B,D. The plasma concentrations of two formulations after single/multiple-dose represented that which was absorbed quickly, initially declined rapidly, then showed a slight decline.

Two participants dropped out during this clinical study. Data (P033) were lost due to the AE of urolithiasis on Day 8 at 4-mg/kg R group. Data (P036) were lost because the investigator concluded that withdrawal would benefit the subject on Day 7 at 4-mg/kg R group.

PK parameters of voriconazole

PK parameters of voriconazole analyses were based on the non-compartmental analysis module. The main PK parameters included C_max, T_max, T_1/2, AUC_0−t, AUC_0−∞, and elimination rate constant (λz). The results of PK parameters of voriconazole after single/multiple doses are listed in Table 2. AUC_0−t occupied more than 90% of AUC_0−∞ in this clinical study, revealing that the plasma concentration–time profiles were well described.

TABLE 2 The pharmacokinetic parameters following single/multiple doses of voriconazole for injection

Summary of main pharmacokinetic parameters of voriconazole for a single dose (D1) and a multiple dose (D10) (mean ± SD, CV%)
	Parameters	3 mg/kg		4 mg/kg
		T (n = 9)	R (n = 9)	T (n = 9)	R (n = 9)
Single-dose	Cmax (ng/ml)	1471.11 ± 227.68 (15.48)	1443.33 ± 449.58 (31.15)	2150.00 ± 340.81 (15.85)	2356.67 ± 251.15 (10.66)
	AUC0−t (h × ng/ml)	5582.80 ± 1063.50 (19.05)	9582.25 ± 9250.95 (96.54)	11179.59 ± 3564.67 (31.89)	13411.03 ± 6067.87 (45.25)
	AUC0−∞ (h × ng/ml)	5721.90 ± 1091.87 (19.08)	10069.34 ± 10064.78 (99.95)	11381.07 ± 3538.49 (31.09)	13596.31 ± 6134.26 (45.12)
	t1/2 (h)	6.27 ± 1.12 (17.88)	7.75 ± 4.62 (59.57)	6.18 ± 1.04 (16.87)	6.66 ± 0.81 (12.11)
	Tmax (h)a	2.00 (1.67 ~ 2.00)	2.00 (1.67 ~ 2.17)	2.17 (2.00 ~ 2.33)	2.00 (1.67 ~ 2.17)
	CL/F(ml/h)	36770.66 ± 7944.45 (21.61)	28463.57 ± 14157.19 (49.74)	23772.41 ± 5551.16 (23.35)	22144.50 ± 10861.72 (49.05)
	Vz/F (ml)	323025.82 ± 31684.51 (9.81)	247401.32 ± 59683.17 (24.12)	208440.15 ± 47310.10 (22.70)	205839.22 ± 88474.58 (42.98)
Multiple-dose steady state	CLss (ml/h)	9368.93 ± 4969.79 (53.05)	6717.65 ± 4129.99 (61.48)	4924.47 ± 1595.85 (32.41)	5800.32 ± 4017.45 (69.26)
	Cmax,ss (ng/ml)	3735.56 ± 1465.28 (39.23)	4792.22 ± 2430.12 (50.71)	6752.22 ± 2128.90 (31.53)	6415.71 ± 1770.92 (27.60)
	Cav,ss (ng/ml)	2292.07 ± 1239.15 (54.06)	3331.35 ± 2275.16 (68.30)	4811.68 ± 1853.74 (38.53)	4418.19 ± 1968.74 (44.56)
	AUCtau (h × ng/ml)	27504.89 ± 14869.77 (54.06)	39976.24 ± 27301.95 (68.30)	57740.14 ± 22244.94 (38.53)	53018.27 ± 23624.86 (44.56)
	Tmax，ss (h)	2.13 ± 0.16 (7.62)	2.11 ± 0.17 (7.91)	2.04 ± 0.18 (8.89)	2.07 ± 0.13 (6.30)
	t1/2 (h)	9.25 ± 4.52 (48.83)	14.08 ± 12.3 (87.56)	11.71 ± 8.43 (71.98)	11.26 ± 4.9 (44.34)
	Vz/F (ml)	106283.48 ± 30539.51 (28.73)	94830.81 ± 22626.74 (23.86)	70139.86 ± 25942.96 (36.99)	77095.90 ± 26715.74 (34.65)
	RAUC (%)	4.71 ± 1.66 (35.31)	4.61 ± 1.28 (27.83)	5.15 ± 1.18 (22.98)	3.92 ± 0.59 (15.00)
	RCmax (%)	2.49 ± 0.64 (25.54)	3.19 ± 0.67 (21.03)	3.14 ± 0.82 (26.06)	2.70 ± 0.72 (26.66)

Note: P033 (4 mg/kg, R group) quitted after completing the first D8 administration and P036 (4 mg/kg, R group) quit after completing the first D7 administration, neither of which could calculate the pharmacokinetic parameters after multiple dose. R_AUC, geometric mean ratio of multiple administration AUC_tau to single administration AUC_0–t; R_Cmax, geometric mean ratio of multiple administration C_max,ss to single administration C_max.

^aT_max was expressed in the median (minimum to maximum).

Single-dose PK of voriconazole: Following the single-dose administration of 3 or 4 mg/kg, peak plasma concentrations were reached at a similar time, with median T_max reaching the peak 2 h after administration. In terms of T_1/2, R formulation was 1.5 h later than T formulation in the 3-mg/kg group, but there were no significant difference in the 4-mg/kg group. C_max and AUC of two formulations increased in an approximately dose-proportional manner across. And, the C_max of T was similar to the R formulation in the 3- and 4-mg/kg group. The AUC of the R formulation was about twice as high as the T formulation in the 3-mg/kg group, but the AUC of the two formulations was close in the 4-mg/kg group.

Multiple-dose PK of voriconazole: Similar to the single-dose administration, the trends of C_max,_ss, C_av,ss, and AUC_tau of two formulations were nearly both in the 3- and 4-mg/kg group. The C_max,_ss, C_av,ss, and AUC_tau of the R formulation were more extensive than the T formulation in the 3-mg/kg group, and the results were reversed in the 4-mg/kg group. The T_max,ss of the T formulation was similar to the R formulation and reached the peak 2 h after administration. The t_1/2 of the T formulation ranged from 5.72 to 30.94 h, and the other went from 5.94 to 45.64 h.

Safety analysis

Throughout the entire clinical trial, 36 HVs were included in the safety analysis after receiving the voriconazole intravenously. AEs were taken as the main evaluation indicators in the safety analysis. The indicators included ocular diseases, gastrointestinal diseases, laboratory examinations, neurological diseases, etc. Furthermore, 29 AEs (100%, 9/9) occurred in the 3-mg/kg T group. Thirty-five AEs (100%, 9/9) occurred in the 3-mg/kg R group. Thirty-seven AEs (100%, 9/9) occurred in the 4-mg/kg T group. Thirty-two AEs (100%, 9/9) occurred in the 4-mg/kg R group. In the 3-mg/kg group, tow subjects (11.1%) had two important AEs, one of all AEs occurred after giving T, and the other was due to R. In the 4-mg/kg group, three subjects (16.7%) had six important AEs, one of all AEs was observed after giving T, and the rest was due to R. Both study groups did not occur serious AEs, serious adverse reactions, or adverse reactions leading to withdrawal.

Two participants drop out during this clinical study, due to the AEs of urolithiasis and the investigator concluded that withdrawal would benefit at 4-mg/kg R group. Data are presented in Table 3.

TABLE 3 Adverse events in the study

SOC/PT	3-mg/kg group				4-mg/kg group
	T (n = 9)		R (n = 9)		T (n = 9)		R (n = 9)
	Case	n (%)	Case	n (%)	Case	n (%)	Case	n (%)
TEAM1	29	9 (100)	35	9 (100)	37	9 (100)	32	9 (100)
Drug-related TEAEs	28	9 (100)	35	9 (100)	36	9 (100)	31	9 (100)
SAMs	0	0 (0)	0	0 (0)	0	0 (0)	0	0 (0)
Drug-related SAMs	0	0 (0)	0	0 (0)	0	0 (0)	0	0 (0)
IAMs	1	1 (11.1)	1	1 (11.1)	1	1 (11.1)	5	2 (22.2)
TEAEs leading to withdrawal	0	0 (0)	0	0 (0)	0	0 (0)	1	1 (11.1)
Drug treatment-related TEAEs	0	0 (0)	0	0 (0)	0	0 (0)	0	0 (0)
Total	29	9 (100)	35	9 (100)	37	9 (100)	32	9 (100)
Ocular diseases	9	7 (77.8)	10	6 (66.7)	13	9 (100)	7	4 (44.4)
Photopsy	7	6 (66.7)	7	5 (55.6)	12	9 (100)	6	3 (33.3)
Visual damage	1	1 (11.1)	2	2 (22.2)	0	0 (0)	0	0 (0)
Amaurosis	1	1 (11.1)	0	0 (0)	0	0 (0)	0	0 (0)
Xerophthalmia	0	0 (0)	1	1 (11.1)	1	1 (11.1)	0	0 (0)
Ophthalmodynia	0	0 (0)	0	0 (0)	0	0 (0)	1	1 (11.1)
Diseases of gastrointestinal system	5	4 (44.4)	9	4 (44.4)	8	7 (77.8)	9	8 (88.9)
Thirst	2	2 (22.2)	4	2 (22.2)	7	7 (77.8)	8	8 (88.9)
Constipation	2	2 (22.2)	3	2 (22.2)	0	0 (0)	0	0 (0)
Dental ulcer	0	0 (0)	2	0 (0)	1	1 (11.1)	1	1 (11.1)
Hematochezia	1	1 (11.1)	0	1 (11.1)	0	0 (0)	0	0 (0)
Laboratory examination	6	4 (44.4)	6	2 (22.2)	3	2 (22.2)	11	3 (33.3)
AST increased	1	1 (11.1)	2	2 (22.2)	0	0 (0)	1	1 (11.1)
γ-GGT increased	1	1 (11.1)	2	2 (22.2)	2	2 (22.2)	1	1 (11.1)
TG increased	1	1 (11.1)	1	1 (11.1)	0	0 (0)	1	1 (11.1)
FIB increased	1	1 (11.1)	0	0 (0)	0	0 (0)	0	0 (0)
D-D dimer increased	1	1 (11.1)	0	0 (0)	0	0 (0)	0	0 (0)
Bacterial positive	1	1 (11.1)	0	0 (0)	0	0 (0)	0	0 (0)
ALT increased	0	0 (0)	1	1 (11.1)	1	1 (11.1)	1	1 (11.1)
LDH increased	0	0 (0)	0	0 (0)	0	0 (0)	1	1 (11.1)
Heart rate increased	0	0 (0)	0	0 (0)	0	0 (0)	6	1 (11.1)
Vascular and lymphatic disease	3	1 (11.1)	3	2 (22.2)	2	1 (11.1)	2	1 (11.1)
Hypertension	2	1 (11.1)	2	1 (11.1)	0	0 (0)	0	0 (0)
Hypotension	1	1 (11.1)	1	1 (11.1)	2	1 (11.1)	2	1 (11.1)
Diseased of the nervous system	3	2 (22.2)	3	1 (11.1)	3	2 (22.2)	0	0 (0)
Headache	1	1 (11.1)	3	1 (11.1)	1	1 (11.1)	0	0 (0)
Swirl	2	1 (11.1)	0	0 (0)	1	1 (11.1)	0	0 (0)
Hypaesthesia	0	0 (0)	0	0 (0)	1	1 (11.1)	0	0 (0)
Diseases of respiratory system, chest, and mediastinum	0	0 (0)	3	1 (11.1)	2	2 (22.2)	0	0 (0)
Epistaxis	0	0 (0)	3	1 (11.1)	2	2 (22.2)	0	0 (0)
Systemic diseases and various reactions at administration sites	2	2 (22.2)	0	0 (0)	3	1 (11.1)	0	0 (0)
Chest discomfort	2	2 (22.2)	0	0 (0)	1	1 (11.1)	0	0 (0)
Chest pain	0	0 (0)	0	0 (0)	2	1 (11.1)	0	0 (0)
Diseases of skin and subcutaneous tissue	0	0 (0)	1	1 (11.1)	0	0 (0)	0	0 (0)
Rash	0	0 (0)	1	1 (11.1)	0	0 (0)	0	0 (0)
Psychotropic	1	1 (11.1)	0	0 (0)	0	0 (0)	0	0 (0)
Injection of fear	1	1 (11.1)	0	0 (0)	0	0 (0)	0	0 (0)
Musculoskeletal and connective tissue diseases	0	0 (0)	0	0 (0)	2	1 (11.1)	0	0 (0)
Physical pain	0	0 (0)	0	0 (0)	1	1 (11.1)	0	0 (0)
Arthralgia	0	0 (0)	0	0 (0)	1	1 (11.1)	0	0 (0)
Diseases of the blood and lymphatic system	0	0 (0)	0	0 (0)	0	0 (0)	1	1 (11.1)
Anemia	0	0 (0)	0	0 (0)	0	0 (0)	1	1 (11.1)
Diseases of kidney and urinary system	0	0 (0)	0	0 (0)	0	0 (0)	1	1 (11.1)
Urolithiasis	0	0 (0)	0	0 (0)	0	0 (0)	1	1 (11.1)
Diseases of the heart organ	0	0 (0)	0	0 (0)	1	1 (11.1)	1	1 (11.1)
Palpitation	0	0 (0)	0	0 (0)	0	0 (0)	1	1 (11.1)
Infranodal extrasystole	0	0 (0)	0	0 (0)	1	1 (11.1)	0	0 (0)

Note: Data are expressed as number of participants (%). In addition to serious adverse events, any adverse events occurring that lead to the introduction of targeted medical measures (such as drug withdrawal, dose reduction, and symptomatic treatment) and significant abnormalities in hematological or other laboratory tests.

Abbreviations: IAEs, important adverse events; SAEs, serious adverse events; TEAEs, treatment-emergent adverse events.

¹Adverse events after first dose.

DISCUSSION

Since Pfizer first launched voriconazole in 2002, voriconazole has been playing an essential role in antifungal therapy to treat invasive aspergillosis.⁹ The voriconazole injection of Hailing Pharmaceutical is a new imitation of Vfend®, which is not on the market yet. The purpose of this clinical research was to understand the similarities between the T (Hainan, Hailing Pharmaceutical) and R (Pfizer) and resolve the remaining non-clinical evaluation.¹⁰ Comparison clinical trials were always required to demonstrate similarity in safety and efficacy between the generic drug and the innovator's product.¹¹ Data and information were required to support the demonstration of interchangeability.¹²

This phase I study revealed that we could not find a significant difference between the T and R formulations in the PK parameters after single/multiples doses. In our clinical study, we found that after a single intravenous dose of 3 mg/kg voriconazole, the AUC_0−t of T and R were found to be 5582.80 ± 1063.50 (h × ng/ml) and 9582.25 ± 9250.95 (h × ng/ml); AUC_0−∞ of T and R were found to be 5721.90 ± 1091.87 (h × ng/ml) and 10069.34 ± 10064.78 (h × ng/ml). After multiple intravenous doses of 3 mg/kg voriconazole, we also found a significant difference between the T and R formulations of PK parameters of AUC_tau. However, after single/multiple intravenous doses of 4 mg/kg voriconazole, the PK parameters of AUC_0−t, AUC_0−∞, and AUC_tau were similar between the T and R formulations. As we know, voriconazole PK is highly variable, and trough concentrations vary more than 100-fold in patients.¹³ Consulting the kinds of literature, we found the results of elimination are approximately linear PK at lower doses, but it's not observed at higher doses.¹⁴ Therefore, we thought that the different dose administrations would influence the metabolism of voriconazole in humans. Nevertheless, the factors influencing human metabolism and the pharmacodynamics of fungal infection treatment remain unclear. Dose-dependent auto-inhibition was put forward as the underlying mechanism for voriconazole's nonlinearity in the previous literature.¹⁵ They had the same discoveries: Hohmann et al. analyzed the PK and metabolism of 50 and 400 mg doses of IV and oral voriconazole, respectively, in HVs,¹⁶ and Jing Zhang et al. had studies done on patients.¹⁷ However, most voriconazole PK equivalence and safety studies were conducted following a single administration.¹⁸ And little or irrelevant between dose and plasma concentration had been reported previously.¹⁹ In our research, we got the PK parameters data of the plasma concentration after multiple doses in Chinese HVs. Meanwhile, from the difference of AUC_0−t between the two formulations, suggestions of dose can be given in clinical medicine about T formulation. Through our single/multiple doses study, the results could provide a basis for our BE evaluation experiment subsequently.

Voriconazole of Vfend and its imitation (Hainan, Hailing Pharmaceutical) were generally well tolerated. In relevant literature reports, the range of AEs to voriconazole was 12.5%–85.7% among individual studies.²⁰ The most common site of AEs mainly occurred in the skin, ocular, and gastrointestinal.²¹ In our study, all AEs were slight. And there was no clinically significant change in laboratory evaluation, 12-lead electrocardiography, and vital signs. A double-blind, placebo-controlled study by Eberhart Zrenner et al. found that the vision of HVs was affected after multiple voriconazole doses.²² In our PK comparison study, the main clinical manifestations of AEs were photopsia, visual damage, amaurosis, xerophthalmia, and ophthalmodynia after dosing, and the characteristics of AEs were lasted a few minutes, exhibited nonprogressive and reversible effects. It's consistent with the previous studies on voriconazole in vivo.²³ During the study, the characteristics of AEs were transient and self-healing. Through the clinical experiments, the probability and frequency of AEs were not significantly different in the 3- and 4-mg/kg groups between the two formulations.

There were still some study limitations: Voriconazole was mainly used in patients with fungal infections, but the subjects were all healthy volunteers in this study. Research has reported that the CYP2C19 PM/extensive metabolizer polymorphism can influence the PK of voriconazole,²⁴ but we did not do further tests.

CONCLUSIONS

The results collected from the PK comparison study demonstrated the biosimilarity between the T formulation (Hailing Pharmaceutical Group) and the R formulation (Vfend®) in healthy Chinese volunteers. The results of this clinical study support the feasibility of further investigation of the efficacy and safety of voriconazole injection of Hailing Pharmaceutical Group healthy Chinese volunteers. And a single-center, randomized, single-dose, 2-cycle, fasting-does BE study has been completed, and the results are forthcoming.

FUNDING INFORMATION

This study was supported by the National Natural Science Foundation of China (81971172), Distinguished Young Scientists, Natural Science Foundation of Zhejiang Province, China (LR21H090001), and The Key Research and Development Program of Zhejiang Province (WKJ-ZJ-1914).

CONFLICT OF INTEREST

Chunqi Huang, Yannan Wang, Yi Wu, Sisi Lin, Rui Hao, Jin Yu, Lu Fang, Jingjing Zhu, Di Zhao, Shengjia Tong, Yongkai Si, Tiantian Ye, Zeyu Wu, Hui Huang, Zhuoyan Wang, and Ying Wang declare that there is no potential conflict of interest.

DATA AVAILABILITY STATEMENT

The datasets generated during and/or analyzed during the current study are available from the corresponding author upon reasonable request.

ETHICS STATEMENT

The trial design was granted by (2021YW042) the National Medical Products Association on March 24, 2021 and the Ethics Committee of the Zhejiang Provincial People's Hospital (Hangzhou City, China). The clinical trial proceeded under the Declaration of Helsinki and its later amendments. All participants signed the informed consent form. The trial was conducted by the Zhejiang Provincial People's Hospital-Phase I Clinical Research Center. The trial was registered at chinadrugtrials.org.cn (NMPA202100180-01).