Side Effects Overview
6 ADVERSE REACTIONS The most common adverse reaction occurring in ≥1% of subjects is nasopharyngitis. (6.1) To report SUSPECTED ADVERSE REACTIONS, contact Acrotech Biopharma Inc. at 1-888-292-9617 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trial Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. The safety of ADQUEY was assessed in two double-blind, vehicle-controlled clinical trials (Trial 2 and Trial 3) that enrolled 532 adult and pediatric subjects 2 years of age and older in Japan with mild to moderate atopic dermatitis (AD). Subjects applied ADQUEY or vehicle ointment topically twice daily for 4 weeks [ see Clinical Studies (14) ]. Adverse reactions reported by ≥1% of ADQUEY-treated subjects and more frequently than in subjects receiving vehicle are listed in Table 1. Table 1: Adverse Reactions Occurring in ≥1% of Adult and Pediatric Subjects 2 Years of Age and Older Treated with ADQUEY for Mild to Moderate Atopic Dermatitis (and Greater than Vehicle) through Week 4 in Trials 2 and 3 Adverse Reaction ADQUEY (N=267) n (%) Vehicle (N=265) n (%) Nasopharyngitis 16(6) 10(4) Less common (<1%) adverse reactions in subjects treated with ADQUEY in Trials 2 and 3 included application site folliculitis, contact dermatitis, application site rash, and molluscum contagiosum. In Trial 1, a vehicle-controlled dose ranging trial, 43 subjects 10 years of age and older in the United States, Australia, and Poland received ADQUEY topically twice daily for 8 weeks and the safety profile was consistent with Trials 2 and 3. In two additional vehicle-controlled dose ranging trials (Trial 4 and Trial 5), 92 subjects 2 years of age and older in Japan received ADQUEY topically twice daily for 4 weeks (Trial 4) and twice daily for 8 weeks (Trial 5) and the safety profile was consistent with Trials 2 and 3. In open-label trials of both Japanese and United States (US) subjects, 857 adult and pediatric subjects continued twice-daily treatment with ADQUEY for up to 52 weeks. The following application site adverse reactions occurred that led to drug discontinuation: pain, pruritus, vesicles, blistering, erythema, burning and contact dermatitis. 6.2 Postmarketing Experience The following adverse reactions have been identified during post approval use of ADQUEY. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. General disorders and administration site condition : application site swelling.
Pharmacokinetics
12.3 Pharmacokinetics Absorption The pharmacokinetics (PK) of ADQUEY were investigated in 31 pediatric subjects 2 years of age and older with moderate to severe atopic dermatitis and a mean ± SD body surface area (BSA) involvement of 44 ± 13% (range 25% to 80%). In this trial, subjects applied an average of approximately 4.3 g of ADQUEY ointment, 1% (dose range was 1.7 to 11.7 g per application) twice daily for 2 weeks. Plasma concentrations were quantifiable in all the subjects. On Day 15, the mean ± SD maximum plasma concentration (C max ) and area under the concentration time curve from 0 to 8 hours post dose (AUC 0-8 ) for difamilast were 16.9 ± 21.9 ng/mL and 86.2 ± 79.6 ng*h/mL, respectively. Systemic concentrations of difamilast were at steady state by Day 15, with no evidence of accumulation. The PK of ADQUEY were investigated in 31 adult subjects with mild to moderate atopic dermatitis and a mean ± SD BSA involvement of 6 ± 3% (range 3% to 19%). Subjects applied an average of approximately 0.9 g of ADQUEY ointment, 1% (dose range was 0.1 to 3.8 g per application) twice daily for 4 weeks. On Day 29, the mean ± SD C max and AUC 0-12 for difamilast were 0.76 ± 1.16 ng/mL and 6.10 ± 8.85 ng*h/mL, respectively. Distribution Difamilast serum protein binding is 99% and is not concentration-dependent, in vitro. Elimination Metabolism Difamilast is substantially metabolized to form three major metabolites in the plasma via CYP3A4-mediated O-deethylation (Metabolite 1), CYP1A2-mediated hydroxylation (Metabolite 2), and enzymatic hydrolysis (Metabolite 3). Excretion After both single dosing and twice daily administration of difamilast ointment 1% in healthy Japanese subjects for 2 weeks, difamilast and Metabolite 1 were undetectable in urine. The urinary excretion ratios of all the other metabolites were less than 0.1% of the administered dose. Specific Populations No dedicated clinical trials have been conducted to assess the impact of intrinsic factors on the PK of difamilast. Based on cross-study analyses, no substantial differences in the PK of difamilast were observed based on age (2-70 years), sex, race, mild or moderate renal impairment, or mild or moderate hepatic impairment. The effect of severe renal impairment (eGFR < 30 mL/min), or severe (Child-Pugh Class C) hepatic impairment on difamilast PK is unknown. Pediatric Patients The plasma difamilast trough concentration corrected by dose in pediatric patients was 1.3 to 1.9 times higher than that in adults (on Day 1 and Day 15, respectively). Drug Interaction Studies Clinical Studies No clinical drug interaction trials have been conducted with topical difamilast. In Vitro Studies CYP450 Enzymes: Difamilast is a substrate of CYP3A4 and CYP1A2. Difamilast is not expected to inhibit CYP1A2, CYP2A6, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP2E1, and CYP3A4 at clinically relevant concentrations. Induction of CYP1A2, CYP2B6, CYP2C9, and CYP3A4 by difamilast is expected to be low at clinically relevant concentrations. Transporter Systems: Difamilast is a substrate of breast cancer resistance protein (BCRP),but is not a substrate of P-glycoprotein (P-gp), OATP1B1, or OATP1B3. Difamilast is not expected to inhibit P-gp, BCRP, OAT1, OAT3, OCT1, OCT2, OATP1B1, OATP1B3, MATE1, or MATE2-K at clinically relevant concentrations.