Effects of Genetic Polymorphisms of Cathepsin A on Metabolism of Tenofovir Alafenamide

Cathepsin A (CatA) is important as a drug-metabolizing enzyme responsible for the activation of prodrugs, such as the anti-human immunodeficiency virus drug Tenofovir Alafenamide (TAF). The present study was undertaken to clarify the presence of polymorphisms of the CatA gene in healthy Japanese subjects and the influence of gene polymorphism on the expression level of CatA protein and the drug-metabolizing activity. Single-strand conformation polymorphism method was used to analyze genetic polymorphisms in healthy Japanese subjects. Nine genetic polymorphisms were identified in the CatA gene. The polymorphism (85_87CTG>-) in exon 2 was a mutation causing a deletion of leucine, resulting in the change of the leucine 9-repeat (Leu9) to 8-repeat (Leu8) in the signal peptide region of CatA protein. The effect of Leu8 on the expression level of CatA protein was evaluated in Flp-In-293 cells with a stably expressed CatA, resulting in the expression of CatA protein being significantly elevated in variant 2 with Leu8 compared with Leu9. Higher concentrations of tenofovir alanine (TFV-Ala), a metabolite of TAF, were observed in the Leu8-expressing cells than in the Leu9-expressing cells using LC/MS/MS. Our findings suggest that the drug metabolic activity of CatA is altered by the genetic polymorphism.

Are Fatigue and Pain Overlooked in Subjects with Stable Chronic Obstructive Pulmonary Disease?

Although there have been many published reports on fatigue and pain in patients with chronic obstructive pulmonary disease (COPD), it is considered that these symptoms are seldom, if ever, asked about during consultations in Japanese clinical practice. To bridge this gap between the literature and daily clinical experience, the authors attempted to gain a better understanding of fatigue and pain in Japanese subjects with COPD. The Brief Fatigue Inventory (BFI) to analyse and quantify the degree of fatigue, the revised Short–Form McGill Pain Questionnaire 2 (SF-MPQ-2) for measuring pain and the Kihon Checklist to judge whether a participant is frail and elderly were administered to 89 subjects with stable COPD. The median BFI and SF-MPQ-2 Total scores were 1.00 [IQR: 0.11–2.78] and 0.00 [IQR: 0.00–0.27], respectively. They were all skewed toward the milder end of the respective scales. A floor effect was noted in around a quarter on the BFI and over half on the SF-MPQ-2. The BFI scores were significantly different between groups regarding frailty determined by the Kihon Checklist but not between groups classified by the severity of airflow limitation. Compared to the literature, neither fatigue nor pain are considered to be frequent, important problems in a real-world Japanese clinical setting, especially among subjects with mild to moderate COPD. In addition, our results might suggest that fatigue is more closely related to frailty than COPD.

1115. Evaluation of Gepotidacin (GSK2140944) Pharmacokinetics and Food Effect in Japanese Subjects

Background Gepotidacin, a novel, first-in-class triazaacenaphthylene antibiotic, inhibits bacterial replication and has in vitro and in vivo activity against key pathogens, including drug-resistant strains, associated with a range of infections. Gepotidacin is currently in Phase 3 clinical studies for the treatment of uncomplicated urinary tract infections and gonorrhea. This study (NCT02853435) was designed to assess gepotidacin pharmacokinetics (PK) in Japanese subjects (fasted and fed). Methods A tablet formulation of 750 mg gepotidacin free base was used in the study, which was conducted in two parts: Part 1, gepotidacin PK was assessed following 1500 and 3000 mg single oral doses in the fasted state; and Part 2, gepotidacin PK was assessed following 1500, 2250, and 3000 mg single oral doses in the fed state. Serial blood and urine samples were collected in both study parts. Results Part 1: The area under the plasma drug concentration-time curve from time 0 to infinity (AUC[0–∞]) and maximum observed concentration (Cmax) were slightly higher in Japanese subjects than in Caucasian subjects at the same dose levels and with the same formulation. Following gepotidacin dosing in the fasted state, the 1500 mg dose was tolerated, while the 3000 mg dose was poorly tolerated with mild or moderate gastro-intestinal adverse effects (GI AEs) reported by most subjects shortly after being dosed. Part 2: PK was linear with doses in the range of 1500–3000 mg. Administration of gepotidacin 3000 mg tablets in the fed state slightly reduced Cmax and slightly increased AUC at the 3000 mg dose level. The 1500 and 2250 mg doses were tolerated while the 3000 mg dose was better tolerated compared to the fasted state with fewer and short-lived GI AEs, mostly mild in intensity. After oral administration of 1500–3000 mg, high urine drug concentrations were achieved, remaining above the minimum inhibitory concentration of 4 μg/mL for up to 24 hours. Conclusion The PK of gepotidacin following administration of a single oral dose to Japanese subjects was linear from 1500–3000 mg and food decreased Cmax without impact on exposure (AUC). Administration of gepotidacin with food resulted in an improved GI tolerability profile at the higher dose tested in Japanese subjects. Disclosures Mohammad Hossain, PhD, GlaxoSmithKline plc. (Employee, Shareholder, Former employee of and past/current shareholder in GlaxoSmithKline plc.) Courtney Tiffany, BSc, GlaxoSmithKline plc. (Employee, Shareholder, Former employee of and past/current shareholder in GlaxoSmithKline plc.) Aline Barth, MSC;PHD, GlaxoSmithKline plc. (Employee, Shareholder, Employee of and shareholder in GlaxoSmithKline plc.) Aparna Raychaudhuri, Ph.D., GlaxoSmithKline plc. (Employee, Shareholder, Former employee of and past/current shareholder in GlaxoSmithKline plc.) Etienne F. Dumont, MD, GlaxoSmithKline plc. (Employee, Shareholder, Former employee of and shareholder in GlaxoSmithKline plc.)

Effect of Conventional Medical Therapy or Laparoscopic Sleeve Gastrectomy on Urinary Albumin in Japanese Subjects with Severe Obesity: An Observational Study

<b><i>Introduction:</i></b> In patients with severe obesity, albuminuria can be improved by both conventional medical therapy and bariatric surgery. The purpose of this study was to compare the impact of weight loss achieved through conventional medical therapy or laparoscopic sleeve gastrectomy (LSG) on albuminuria in Japanese subjects with severe obesity and identify the factors involved. <b><i>Methods:</i></b> We retrospectively evaluated the clinical characteristics including the urinary albumin/creatinine ratio (UACR) of 340 consecutive subjects with a body mass index ≥35 who received LSG (<i>n</i> = 242) or medical therapy (<i>n</i> = 98) between 2010 and 2018 and were followed for at least 12 months. <b><i>Results:</i></b> The baseline of the UACR was not different between the 2 groups. At the 12-month follow-up, total weight loss (TWL) and decreases in glycosylated hemoglobin (HbA1c) and log_e UACR were greater in the LSG group than in the medical therapy group (body weight; −35.7 kg vs. −8.0 kg, <i>p</i> &#x3c; 0.001, HbA1c; −1.4% vs. −0.7%, <i>p</i> &#x3c; 0.001, log_e UACR; −0.3 vs. 0.9, <i>p</i> &#x3c; 0.001). The rate of complete remission of diabetes was significantly higher in the LSG group than in the medical therapy group. At 12 and 36 months (<i>n</i> = 111 in the medical therapy group, <i>n</i> = 56 in the LSG group at 36 months), log_e UACR increased in the medical therapy group, while it remained unchanged or decreased in the LSG group. In subjects with microalbuminuria and macroalbuminuria, changes in the log_e UACR correlated with percent total body weight loss (%TWL) in both groups at 12 months. Percent TWL contributed independently to the change in the log_e UACR, irrespective of whether LSG was performed. In receiver-operating characteristic analysis, a weight loss of 7.8% predicted a decrease in the UACR (∆UACR &#x3c;0 at 12 months). <b><i>Conclusion:</i></b> Our analysis suggests that albuminuria may increase over time if only medical therapy is continued. To improve albuminuria, weight loss may be more important than whether LSG is performed.

Does reactogenicity after a second injection of the BNT162b2 vaccine predict spike IgG antibody levels in healthy Japanese subjects?

Background Adverse reactions are more common after the second injection of messenger RNA vaccines such as Pfizer/BioNTech’s BNT162b2. We hypothesized that the degree and severity of reactogenicity after the second injection reflects the magnitude of antibody production against the SARS CoV-2 virus spike protein (spike IgG). Methods and results Blood samples were obtained from 67 Japanese healthcare workers three weeks after the first injection and two weeks after the second injection of the BNT162b2 vaccine to measure spike IgG levels. Using questionnaires, we calculated an adverse event (AE) score (0–11) for each participant. The geometric mean of spike IgG titers increased from 1,047 antibody units (AU/mL) (95% confidence interval (95% CI): 855–1282 AU/mL) after the first injection to 17,378 AU/mL (95% CI: 14,622–20,663 AU/mL) after the second injection. The median AE score increased from 2 to 5. Spike IgG levels after the second injection were negatively correlated with age and positively correlated with spike IgG after the first injection. AE scores after the second injection were not significantly associated with log-transformed spike IgG after the second injection, when adjusted for age, sex, AE score after the first injection, and log-transformed spike IgG after the first injection. Conclusions Although the sample size was relatively small, reactogenicity after the second injection may not accurately reflect antibody production.