新型抗真菌药物研究进展

侵袭性真菌感染(invasive fungal infections,IFI)以其逐年上升的发病率和致死率,已经成为人类健康的严重威胁。临床常用的抗真菌药物包括氮唑类、多烯类以及棘白菌素类等。药物治疗作为应对IFI的主要策略,现有的药物种类明显不足,并且受到真菌耐药性和药物毒副作用等越来越多的制约,使得对抗真菌新药的需求愈加迫切。新型抗真菌药物的研发策略主要包括改造现有临床常用药物和发现新靶点药物两个方面。近年值得关注的研发中的新型抗真菌药物包括:氮唑类药物VT-1161和VT-1129、葡聚糖合成酶抑制剂CD101和SCY-078、GPI锚合成抑制剂E1210、嘧啶合成抑制剂F901318、抗真菌中药和增效剂,以及其他抗真菌新药如T-2307、尼可霉素Z和VL-2397等。该文主要综述了上述新药的研究进展,包括作用机制、体内外活性以及临床试验等。     

白色念珠菌氟康唑耐药相关基因研究进展

近 2 0年来由于临床上对癌症患者、器官移植患者大量使用化疗药物、广谱抗生素和免疫抑制剂 ,以及艾滋病 (AIDS)的流行 ,使深部真菌感染的发生率在免疫受损的病人群体中急剧升高。深部真菌感染已日益成为一种常见病、多发病 ,并已逐渐成为这类疾病患者死亡的主要原因之一。深部真菌感染中最常见菌属是念珠菌属 (Candidaspecies) ,其中以白色念珠菌 (Candidaalbicans)为最常见菌种。目前临床上常用的抗真菌药物有两大类 :干扰真菌细胞膜脂质合成的药物(二性霉素B ,唑类药物 )和干扰真菌核酸合成的药物 (5 氟胞嘧啶 )。由于唑类药物中的氟…     

三唑类抗真菌新药泊沙康唑和伏立康唑简介

随着侵袭性真菌感染的发病率和死亡率逐年增多,新近问世的新型抗真菌药物也越来越多。新一代广谱三唑类抗真菌药物泊沙康唑和伏立康唑,在体内和体外均有较强的抗真菌活性,临床上用其来预防和治疗侵袭性真菌感染。两药具有共有的作用机制,在抗真菌活性、药物代谢及安全性方面有着各自特点。分子结构上泊沙康唑和伏立康唑优于原有药物伊曲康唑和氟康唑,从而具备更强、更广的抗菌谱。两药的研发和应用表明抗真菌药物研究正朝着高效、广谱、低毒的方向发展,成为治疗各种类型真菌感染新的有力手段。然而,两药在临床研究和血药浓度监测方面仍待深入探究。本文将从分子结构、作用机制、适应症和药代动力学方面介绍两药,并对两药在未来的临床应用进行展望,为临床应用提供帮助。     

棘白菌素类抗真菌药

棘白菌素（Echinocandins）是一类新型抗真菌药物,自21世纪初开始在临床上应用,Et前已上市的药物包括卡泊芬净（caspofungin）、米卡芬净（micafungin）、阿尼芬净（anidulafungin）。现对这3种药物的结构特点、作用机制、药代动力学、抗真菌谱、适应症、不良反应、药物相互作用、禁忌症等方面的研究现状和进展加以介绍。     

米卡芬净预防血液系统恶性肿瘤患者侵袭性真菌感染有效性和安全性的Meta分析

目的系统评价米卡芬净预防血液系统恶性肿瘤患者侵袭性真菌感染(IFIs)的有效性及安全性,为临床治疗提供循证参考。方法计算机检索PubMed、Embase、Cochrane图书馆、中国知网(CNKI)、万方数据,检索时限为建库起至2021年1月,收集米卡芬净(试验组)对比常规抗真菌药物(两性霉素B及三唑类抗真菌药,对照组)的随机对照试验(RCT),对符合纳入标准的临床研究进行资料提取并采用Cochrane系统评价员手册5.0.2进行质量评价后,采用Rev Man 5.3统计软件对突破性IFIs、真菌感染死亡率、全因死亡率及因不良反应停药的发生率进行Meta分析。结果共纳入9项RCT,合计2 479例患者。Meta分析结果显示,试验组患者突破性IFIs发生率[OR=0.74,95%CI(0.50,1.07),P=0.11]、真菌感染死亡率[OR=0.73,95%CI(0.46,1.17),P=0.19]和全因死亡率[OR=0.94,95%CI(0.69,1.28),P=0.7]与对照组相比,差异无统计学意义;因不良反应停药的发生率[OR=0.46,95%CI(0.32,0.66),P<0.0001]显著低于对照组,差异有统计学意义。结论米卡芬净用于预防血液系统恶性肿瘤患者IFIs的效果与两性霉素B及三唑类抗真菌药物相当,且安全性更高。     

国产卡泊芬净对曲霉菌的体外活性评估

目的以进口卡泊芬净(原研药)为对照,评估国产卡泊芬净(仿制药)对曲霉菌的体外抗菌活性及与进口卡泊芬净的一致性。方法 利用北京协和医院分离的75株侵袭性曲霉菌,采用CLSI推荐的微量液基稀释法对8种抗真菌药物进行体外敏感性试验。结果 棘白菌素类药物的MEC值总体低于唑类药物的MIC值,而米卡芬净的MEC 50 和MEC 90 比卡泊芬净低出2个梯度。除了对1株黄曲霉的MIC值为4 μg/mL,两性霉素B对其余74株菌株的MIC值≤2 μg/mL。全部菌株对伏立康唑和泊沙康唑均敏感,分别有16株烟曲霉、2株黄曲霉和5株黑曲霉对伊曲康唑耐药。国产卡泊芬净和进口卡泊芬净仅对11株曲霉菌的MEC值存在不一致,且国产卡泊芬净仅较卡进口泊芬净只低一个浓度梯度。卡泊芬净和米卡芬净对超过76%的曲霉菌24 h和48 h的药敏测定结果完全一致。结论 相较于唑类药物和两性霉素B,卡泊芬净对曲霉菌具有很好的体外抗真菌活性,且国产卡泊芬净与进口卡泊芬净的体外抗菌活性基本高度一致。     

基于新靶点的抗真菌药物研究进展

侵袭性真菌感染的发病率正逐年上升。现有抗真菌药物由于抗菌谱有限、副作用大等原因,致使临床应用受限。因此,基于新靶点的抗真菌药物成为治疗真菌感染的迫切需要。近年来,抗真菌药物研究取得较大进展。其中,抑制真菌细胞壁合成的药物（如E1210和D11?2040）、抑制蛋白激酶或蛋白磷酸酶信号通路的药物（如KP?372?1、17?AAG、Mycograb）、靶向真菌毒力因子的单克隆抗体（如C7、213 Bi?18B7、188 Re?18B7）、激活宿主免疫系统的疫苗[如PEV7和β?（ Man）3?Fba?TT]等,正引起人们的关注。     

天然植物抗假丝酵母菌活性成分的研究

临床真菌感染的发病率和死亡率逐年上升,其中以假丝酵母菌为代表的侵袭性真菌感染尤为严重,目前主要抗真菌药物的耐药性日趋严重,且多数具有毒副作用,寻找安全有效的新型抗真菌药物迫在眉睫。天然植物中抗真菌活性成分来源广泛,具有低毒、广谱、作用途径多样化等优点,成为新型抗真菌药物的一个重要研究方向。本文主要综述了近年来从天然植物中筛选抗假丝酵母菌活性成分的研究。     

抗侵袭性真菌感染单克隆抗体研究进展

近20多年来,随着免疫缺陷患者的增多,侵袭性真菌感染发病率呈持续上升趋势,死亡率高居不下。现用的抗真菌药物主要有氮唑类、多烯类、棘白菌素类等,存在品种少、真菌耐药性增加和毒副作用大等问题,迫切需要研制新型抗真菌药物。单克隆抗体具有精准靶向的抗真菌作用,兼有调节机体免疫反应的功能,是治疗真菌感染的一种可行且具有独特优势的药物。从作用靶点分类,可以分为靶向真菌表面多糖、毒力因子、蛋白和跨界抗真菌单克隆抗体。从抗体来源分类又可以分为天然抗体和重组抗体。其作用机制包括直接抗真菌作用,即对毒素中和或对真菌的直接抑制作用;以及免疫增强作用,主要是补体的活化以驱动吞噬细胞清除或破坏致病真菌、中性粒细胞调理吞噬作用的激活以及诱导巨噬细胞调理吞噬。本文从药效学等方面总结了目前抗真菌感染单克隆抗体的研究进展,以及存在的问题。此外,针对抗真菌单克隆抗体的新型制备方法与传统制备方法进行了对比,并探讨了未来的发展方向。     

侵袭性真菌感染的分子诊断现状

近年来陧袭性真菌感染的发病率不断升高,侵袭性真菌感染的早期、准确诊断对于合理选用抗真菌药物,提高抗真菌疗效至关重要：另外,及时诊断侵袭性真菌感染可以减少经验性抗真菌治疗,降低抗真菌药物的选择性压力,     

Hsp21 Potentiates Antifungal Drug Tolerance in Candida albicans

Systemic infections of humans with the fungal pathogen Candida albicans are associated with a high mortality rate. Currently, efficient treatment of these infections is hampered by the relatively low number of available antifungal drugs. We recently identified the small heat shock protein Hsp21 in C. albicans and demonstrated its fundamental role for environmental stress adaptation and fungal virulence. Hsp21 was found in several pathogenic Candida species but not in humans. This prompted us to investigate the effects of a broad range of different antifungal drugs on an Hsp21-null C. albicans mutant strain. Our results indicate that combinatorial therapy targeting Hsp21, together with specific antifungal drug targets, has strong synergistic potential. In addition, we demonstrate that Hsp21 is required for tolerance to ethanol-induced stress and induction of filamentation in response to pharmacological inhibition of Hsp90. These findings might pave the way for the development of new treatment strategies against Candida infections.     

Rare Fungal Infections in Children: An Updated Review of the Literature

An increasing trend of reports of rare fungal diseases has been observed to be mainly associated with the substantial increase of high-risk immunocompromised children, as well as with the selective pressure of antifungal drugs. On the other hand, recent reports have shown that several species of these rare fungi may also cause infections in immunocompetent children without obvious underlying conditions. The clinical spectrum of these infections, and most importantly their outcome, varies greatly, implying for a rather heterogenic group of pediatric infections. Various types of superficial and subcutaneous fungal infections, as well as systemic and disseminated life-threatening infections, have been reported. Prompt diagnosis and appropriate treatment of rare fungal diseases in children remains a great challenge. Several treatment options have been used, ranging from localized to combination treatment with extensive surgical excision and long-term antifungal therapy. We review contemporary data of rare fungal infections in pediatric patients focusing on epidemiology, mycology, management and outcome, published during the last three years.     

The role of adjuvant agents in treating fungal diseases

Invasive fungal infections (IFIs) remain a significant cause of morbidity and mortality despite the recent introduction of new antifungal medications. In this review, the available data on the use of adjuvant agents for the treatment of IFIs are discussed. Cytokines such as interferon-γ, colony-stimulating factors, granulocyte transfusions, and the monoclonal antibody efungumab may have in a role in the management of IFIs through augmentation of the host immune response, whereas pathogen-specific vaccines may help prevent infection. Pentraxin 3, an acute phase protein, may assist in the prevention and treatment of aspergillosis. Deferasirox, an iron chelator, is being investigated as an adjunctive therapy for the treatment of zygomycosis. Lactoferrin, an ironbinding protein, appears to have activity in Candida and Aspergillus infections, and omiganan may help prevent fungal catheter-related infections. Although none of these agents are currently approved for the treatment of IFIs, they may be involved in current and/or future treatment options when used in combination with antifungal drugs.     

Synergy between ajoene and ketoconazole in isolates of Microsporum canis. A preliminary study using fractional inhibitory concentration technique (FIC)

Fungal infections are probably the most frequent infectious diseases affecting human being. Resistance to different anti-fungal drugs, and their bioavailability in the infection site, represent a problem for treatment. Looking for effective solutions, combination of two or more antifungal drugs to obtain an additive effect or synergic effect that potent antifungal activity has been investigated. In this study, the effect (additive, antagonist or synergistic) of ajoene and ketoconazole combination was evaluated in the growth and proliferation of filamentous fungi. Interactions in vitro were investigated in three isolates of Microsporum canis through a preliminary study using micro dilution, according to recommendations of NCCLS M-38A, with several modifications. Results obtained for CIF of each isolates studied (CIF = 0.18 0.36 microM), demonstrate that exists a very potent synergistic effect, when they are combined, and it represents a hope for future clinic trials to treat resilient fungal infections caused by M. canis.     

AmBisome,tres retos: infección por Candida auris,infección del sistema nervioso central e infección asociada a biopelículas

The treatment of invasive fungal infections remains a challenge, both for the diagnosis and for the need of providing the appropriate antifungal therapy. Candida auris is a pathogenic yeast that is responsible for hospital outbreaks, especially in intensive care units; it is characterized by a high resistance to the antifungal agents and can become multidrug-resistant. At present, the recommended antifungal agents for the invasive infections with this pathogen are echinocandins, always after carrying out an antifungal susceptibility testing. In case of no clinical response or persistent candidemia, the addition of liposomal amphotericin B or isavuconazole may be considered. Both fungal infection of the central nervous system and that associated with biomedical devices remain rare entities affecting mainly immunocompromised patients. However, an increase in their incidence in recent years, along with high morbidity and mortality, has been shown. The treatment of these infections is conditioned by the limited knowledge of the pharmacokinetic properties of antifungals. A better understanding of the pharmacokinetic and pharmacodynamic parameters of the different antifungals is essential to determine the efficacy of the antifungal agents in the treatment of these infections.     

Antifungals discovery: an insight into new strategies to combat antifungal resistance

Undeniably, new antifungal treatments are necessary against pathogenic fungi. Fungal infections have significantly increased in recent decades, being highlighted as important causes of morbidity and mortality, particularly in immunocompromised patients. Five main antifungal classes are used: (i) azoles, (ii) echinocandins, (iii) polyenes, (iv) allylamines and (v) pyrimidine analogues. Moreover, the treatment of mycoses has several limitations, such as undesirable side effects, narrow activity spectrum, a small number of targets and fungal resistance, which are still of major concern in clinical practice. The discovery of new antifungals is mostly achieved by the screening of natural or synthetic/semisynthetic chemical compounds. The most recent discoveries in drug resistance mechanism and their avoidance were explored in a review, focusing on different antifungal targets, as well as new agents or strategies, such as combination therapy, that could improve antifungal therapy.

Significance and Impact of the Study

The failure to respond to antifungal therapy is complex and is associated with microbiological resistance and increased expression of virulence in fungal pathogens. Thus, this review offers an overview of current challenges in the treatment of fungal infections associated with increased antifungal drug resistance and the formation of biofilms in these opportunistic pathogens. Furthermore, the most recent and potential strategies to combat fungal pathogens are explored here, focusing on new agents as well as innovative approaches, such as combination therapy between antifungal drugs or with natural compounds.     

In?vitro and in?vivo study on the effect of antifungal agents on hematopoietic cells in mice

Liposomal amphotericin B, voriconazole, and caspofungin are currently used for systemic and severe fungal infections. Patients with malignant diseases are treated with granulocyte-colony stimulating factor (G-CSF) for the recovery of granulocytes after chemotherapy or hematopoietic cell (HC) transplantation. Since they have a high incidence of fungal infections, they inevitably receive antifungal drugs for treatment and prophylaxis. Despite their proven less toxicity for various cell types comparatively with amphotericin B and the decrease in the number of leukocytes that has been reported as a possible complication in clinical studies, the effect of liposomal amphotericin B, voriconazole, and caspofungin on HCs has not been clarified. The present study aimed to examine the in vitro and in vivo effect of these three modern antifungals on HCs. Colony-forming unit (CFU) assays of murine bone marrow cells were performed in methylcellulose medium with or without cytokines and in the presence or absence of various concentrations of liposomal amphotericin B, voriconazole, and caspofungin. In the in vivo experiments, the absolute number of granulocytes was determined during leukocyte recovery in sublethally irradiated mice receiving each antifungal agent separately, with or without G-CSF. In vitro, all three antifungal drugs were nontoxic and, interestingly, they significantly increased the number of CFU-granulocyte-macrophage colonies in the presence of cytokines, at all concentrations tested. This was contrary to the concentration-dependent toxicity and the significant decrease caused by conventional amphotericin B. In vivo, the number of granulocytes was significantly higher with caspofungin plus G-CSF treatment, higher and to a lesser extent higher, but not statistically significantly, with voriconazole plus G-CSF and liposomal amphotericin B plus G-CSF treatments, respectively, as compared with G-CSF alone. These data indicate a potential synergistic effect of these antifungals with the cytokines, in vitro and in vivo, with subsequent positive effect on hematopoiesis.     

An update on the pharmacoeconomics of antifungal pharmacotherapy

The incidence and severity of invasive fungal infections are on the rise and they pose a risk of significant morbidity and mortality. The cost burden of fungal infections in the United States is high. There are many newer, less toxic antifungal agents to manage these challenging infections; however, these agents also carry a high cost of their own. When considering an antifungal agent for a specific patient, it is important to consider safety, efficacy, and cost, thus making it essential to continually evaluate the antifungal pharmacoeconomic literature to assist in the therapeutic decision-making process for patients with invasive fungal infections. Unfortunately, there is a lack of pharmacoeconomic studies addressing the costs associated with the treatment and prevention of fungal infections. Future large-scale clinical studies should include pharmacoeconomic analyses and end points that encompass all costs associated with antifungal drug use, not solely drug acquisition costs.