Pharmacokinetics of oral neratinib during co-administration of ketoconazole in healthy subjects

AIM

The primary objective was to evaluate the pharmacokinetics of a single dose of neratinib, a potent, low-molecular-weight, orally administered, irreversible pan-ErbB (ErbB-1, -2, -4) receptor tyrosine kinase inhibitor, during co-administration with ketoconazole, a potent CYP3A4 inhibitor.

METHODS

This was an open-label, randomized, two-period, crossover study. Fasting healthy adults received a single oral dose of neratinib 240 mg alone and with multiple oral doses of ketoconazole 400 mg. Blood samples were collected up to 72 h after each neratinib dose. Plasma concentration data were analyzed using a noncompartmental method. The least square geometric mean ratios [90% confidence interval (CI)] of C_max(neratinib+ketoconazole) : C_max(neratinib alone), and AUC(neratinib+ketoconazole) : AUC(neratinib alone) were assessed.

RESULTS

Twenty-four subjects were enrolled. Compared with neratinib administered alone, co-administration of ketoconazole increased neratinib C_max by 3.2-fold (90% CI: 2.4, 4.3) and AUC by 4.8-fold (3.6, 6.5). Median t_max was 6.0 h with both regimens. Ketoconazole decreased mean apparent oral clearance of neratinib from 346 l h⁻¹ to 87.1 l h⁻¹ and increased mean elimination half-life from 11.7 h to 18.0 h. The incidence of adverse events was comparable between the two regimens (50% neratinib alone, 65% co-administration with ketoconazole).

CONCLUSION

Co-administration of neratinib with ketoconazole, a potent CYP3A inhibitor, increased neratinib C_max by 3.2-fold and AUC by 4.8-fold compared with administration of neratinib alone. These results indicate that neratinib is a substrate of CYP3A and is susceptible to interaction with potent CYP3A inhibitors and, thus, dose adjustments may be needed if neratinib is administered with such compounds.     

建立用大鼠肝微粒体快速考察药物体外CYP3A1活性抑制的方法

目的 研究酮康唑对大鼠肝微粒体细胞色素P450同工酶3A1( CYP3A1)活性的作用,建立一种用大鼠肝微粒体快速考察药物体外CYP3A1活性抑制的方法.方法 采集大鼠肝微粒体,随机分为对照组和药物处理组.酮康唑药物处理组分别加入不同浓度的酮康唑,对照组只加入培养液,混匀后放入37℃培养箱中孵育15 min,然后加入CYP 3A1底物睾酮,继续孵育10 min,最后加入内标物氢化可的松.用HPLC法测定睾酮经大鼠肝微粒体温孵后生成6-β羟基睾酮的量,代表CYP3A1的活性.结果 各个处理组与对照组的比较差异均有显著性差异(P＜0.05);提示在一定浓度范围内,大鼠同工酶CYP3A1的相对活性百分比随着酮康唑浓度的增加而逐渐减低,各处理组与对照组比较差异均有显著性意义(P＜0.5).半数抑制浓度( IC50)值为3.25 μg/ml.结论 酮康唑对大鼠肝微粒体细胞色素P450同工酶3A1的活性有强抑制作用,建立的通过大鼠肝微粒体快速考察药物体外CYP3A1探针抑制的方法重复性和稳定性均良好,为评价新药对大鼠肝微粒体CYP3A1的活性的体外作用提供可靠的检测手段.     

萘替芬酮康唑乳膏联合地奈德乳膏治疗面部脂溢性皮炎疗效观察

目的:观察萘替芬酮康唑乳膏及地奈德乳膏联合疗法治疗面部脂溢性皮炎的临床疗效。方法:30例面部脂溢性皮炎应用萘替芬酮康唑乳膏及地奈德乳膏联合外用治疗,治疗,2,3周及4周结束后观察临床疗效及不良反应,停药后1,2周随诊。结果:4周后痊愈率为86.67%,总有效率为100%。停药后1,2周随诊未见复发。未发现不良反应。结论:此方法治疗面部脂溢性皮炎治愈率高,疗效显著,耐受性好,安全性高,复发率低,是一种较理想的治疗面部脂溢性皮炎的有效方法。     

Biotransformation and in vitro assessment of metabolism-associated drug–drug interaction for CRx-102, a novel combination drug candidate

CRx-102 is an oral synergistic combination drug which contains the cardiovascular agent, dipyridamole (DP) and a very low dose of the glucocorticoid, prednisolone (PRED). CRx-102 works through a novel mechanism of action in which DP selectively amplifies the anti-inflammatory activity of PRED without replicating its side effects. CRx-102 is in clinical trials for the treatment of osteoarthritis. Here we delineate the in vitro metabolism and explore the potential for a drug–drug interaction between the active agents in CRx-102. Our study using human hepatocyte suspensions showed that both DP and PRED were metabolized by CYP3A4 isozymes, resulting in the formation of diverse arrays of both oxidative and oxidative-reduced metabolites. Within phase 1 biotransformation, CYP3A4 was one of the pathways responsible for the metabolism of PRED, while phase 2 biotransformation played a significant role in the metabolism of DP. Glucuronidation of DP was substantial and was catalyzed by many UGT members, specifically those in the UGT1A subfamily. Based on the tandem mass (MS/MS) product ion spectra (PIS) acquired, the major metabolites of both agents, namely, monooxygenated, mono-N-deethanolaminated, dehydrogenated and O-glucuronidated metabolites of DP and the monooxygenated (e.g., 6-hydroxyl), dehydrogenated (prednisone) and reduced (20-hydroxyl) metabolites of PRED, were identified and elucidated. The affinities for DP biotransformation, including CYP3A4-mediated oxidative pathways and UGT-mediated O-glucuronidation, appeared high (K_m < 10 μM), as compared with the modest affinities of PRED biotransformation catalyzed by CYP3A4 (K_m ∼ 40–170 μM). DP, but not PRED, exerted a minimal inhibitory effect on the drug-metabolizing CYP isoforms, including CYP3A4, which was determined using a panel of CYP isoform-preferred substrate activities in pooled human liver microsomal (HLM) preparations and microsomal preparations containing the recombinant enzymes (K_i ∼ 2–12 μM). Using the DP maximal plasma concentration (C_max) observed in the clinic and a predictive mathematical model for metabolism-associated drug–drug interaction (DDI), we have demonstrated that there is little likelihood of a pharmacokinetic interaction between the two active agents in CRx-102.     

电位滴定法测定酮康唑含量能力验证的结果分析

以酮康唑为模型药物,统计了CNAS T0382电位滴定法测定药品含量能力验证的结果,并对离群数据进行技术分析.     

In vitro susceptibility of the seven Malassezia species to ketoconazole, voriconazole, itraconazole and terbinafine

Fifty-five strains, either authentic or ex-type, of seven Malassezia species were investigated for in vitro susceptibility to various concentrations (0.03-64.0 microg/mL) of three azole drugs, ketoconazole, voriconazole and itraconazole, as well as the allylamine terbinafine, using the agar dilution method. All strains of the seven Malassezia species were susceptible to the three azole drugs at low concentrations. M. furfur, M. sympodialis, M. slooffiae, M. pachydermatis, M. globosa, M. obtusa and M. restricta were most sensitive to ketoconazole and itraconazole, with minimum inhibitory concentrations (MICs) ranging from < or = 0.03 to 0.125 microg/mL. The recently introduced antifungal, voriconazole, was also very effective, with MIC80 values < or = 0.03 microg/mL for 80% of strains. MICs of terbinafine against the seven Malassezia species ranged from ketoconazole, voriconazole, itraconazole and terbinafine. Strains of M. furfur, M. globosa and M. obtusa were more tolerant to terbinafine than the remaining Malassezia species; M. sympodialis was highly susceptible. M. furfur strains tested with terbinafine ranged from highly susceptible to relatively resistant. Correct identification of Malassezia species could facilitate selection of appropriate antifungal therapy.     

Comparative efficacy of various treatment regimens for androgenetic alopecia in men

Our understanding of the aetiology of androgenetic alopecia (AGA) has substantially increased in recent years. As a result, several treatment modalities have been tried with promising results especially in early stages of AGA. However, as far as has been ascertained, there is no comprehensive study comparing the efficacy of these agents alone and in combination with each other. One hundered male patients with AGA of Hamilton grades II to IV were enrolled in an open, randomized, parallel-group study, designed to evaluate and compare the efficacy of oral finasteride (1 mg per day), topical 2% minoxidil solution and topical 2% ketoconazole shampoo alone and in combination. They were randomized into four groups. Group I (30 patients) was administered oral finasteride, Group II (36 patients) was given a combination of finasteride and topical minoxidil, Group III (24 patients) applied minoxidil alone and Group IV (10 patients) was administered finasteride with topical ketoconazole. Treatment efficacy was assessed on the basis of patient and physician assessment scores and global photographic review during the study period of one year. At the end of one year, hair growth was observed in all the groups with best results recorded with a combination of finasteride and minoxidil (Group II) followed by groups IV, I and III. Subjects receiving finasteride alone or in combination with minoxidil or ketoconazole showed statistically significant improvement (p<0.05) over minoxidil only recipients. No signifcant side-effects related to the drugs were observed. In conclusion, it is inferred that the therapeutic efficacy is enhanced by combining the two drugs acting on different aetiological aspects of AGA.     

Subcutaneous zygomycosis: report of 10 cases from two institutions in North India

Background Subcutaneous zygomycosis is an uncommon condition observed in tropics. Few series have been published, particularly from the northern regions of India. Objectives The aim of this study was to describe clinical, investigative and therapeutic details in subcutaneous zygomycosis observed in two teaching hospitals in Delhi. Patients and methods Ten patients seen over a period of 10 years (1999–2009) form the material for this report. Results There were four children and six adults. In four children, the presentation was a subcutaneous localized mass or gradually spreading plaque. In the others, it was observed over nasal region of face, spreading inward into mucosal sites and paranasal sinuses, and outward to the contiguous areas. Regional lymphadenopathy was present in two with facial lesions. Majority showed a granulomatous infiltrate with admixture of other cells, mainly eosinophils. Aseptate or poorly septate hyphae were observed in seven. In one patient in whom no hyphae were observed, there was dense perivascular inflammation. Organisms were cultured from four patients, Basidiobolus ranarum in two and Syncephalastrum racemosum in two. The main therapy used was a saturated solution of potassium iodide (KI). Four received only KI of which two attained cure after 3 months and 9 months respectively, and the other two showed signs of regression. In one boy subsidence was associated with reduced circumference of thigh. Ketoconazole or itraconazole was given with KI to hasten regression when response was slow or there were side‐effects to KI. Conclusion Awareness and early recognition will prevent disfigurement produced by advanced disease, misdiagnosis and unnecessary surgical intervention.     

Topical 2% ketoconazole cream monotherapy significantly improves adult female acne: A double‐blind,randomized placebo‐controlled trial

The emergence of bacterial resistance is a global crisis. Prolonged use of antibiotics especially in acne is one issue of concern among dermatologists. Ketoconazole (KTZ) cream, a topical antifungal with anti‐inflammatory and antiandrogenic actions, can decrease lipase activity of Cutibacterium acnes in vitro. We evaluated the efficacy and safety of KTZ cream in mild adult female acne (AFA) by conducting a randomized, double‐blind, placebo‐controlled trial using KTZ 2% and placebo cream twice daily for 10 weeks. We assessed the improvement of clinical severity, measured by AFA score graded by investigators and participants, and the change of acne count. Forty‐one participants enrolled in our study. The proportion of participants with acne improvement from baseline (42.9% vs 9.5%, P = 0.015) and the success rate (45.0% vs 14.3%, P = 0.043) in the KTZ group were significantly higher than that of the placebo group. The most common adverse events were dryness and itching. The percentage change of acne count decreased significantly compared with baseline but did not differ statistically between the two groups (P = 0.268). We concluded that the KTZ monotherapy showed a plausible effect in improving AFA with excellent safety profile. It should be considered as a viable option for mild AFA treatment.     

Effect of a single administration of ketoconazole on total and physiologically free plasma testosterone and 17β-oestradiol levels in healthy male volunteers

Summary The effect of a single oral dose of 400 mg ketoconazole, given as an 80 mg/ml suspension, on total and physiologically free (i.e. non-sex hormonebound) testosterone and 17-oestradiol has been investigated in 6 healthy male volunteers. The two steroids fell to nadir levels of 18 and 60% of their respective initial concentrations 6 hours after drug intake, and then completely recovered. Although in vitro slight displacement of testosterone from the sex-hormone binding globulin, by high doses of ketoconazole was found, the physiologically free concentration of testosterone in vivo was closely correlated with that of the total hormone, suggesting that there is no direct interference with sex-hormone binding globulin in vivo. Plasma LH and FSH were not significantly modified by treatment. The effect of ketoconazole on plasma oestradiol levels was less pronounced and was not clearly related to a block of the aromatase system, as reported in vitro.This work was presented in part at the International Symposium on the Regulation of Androgen Actions, Montreal, 29th June–1st July 1984