Cisplatin-Associated Ototoxicity: A Review for the Health Professional

Cisplatin is an effective drug used in the treatment of many cancers, yet its ototoxic potential places cancer patients, exposed to this drug, at risk of hearing loss, thus negatively impacting further on a patient’s quality of life. It is paramount for health care practitioners managing such patients to be aware of cisplatin’s ototoxic properties and the clinical signs to identify patients at risk of developing hearing loss. English peer-reviewed articles from January 1975 to July 2015 were assessed from PubMed, Science Direct, and Ebscohost. Seventy-nine articles and two books were identified for this review, using MeSH terms and keywords such as “ototoxicity”, “cisplatin”, “hearing loss”, and “ototoxicity monitoring”. This review provides an up-to-date overview of cisplatin-associated ototoxicity, namely, its clinical features, incidence rates, and molecular and cellular mechanisms and risk factors, to health care practitioners managing the patient with cancer, and highlights the need for a team-based approach to complement an audiological monitoring programme to mitigate any further loss in the quality of life of affected patients, as there is currently no otoprotective agent recommended routinely for the prevention of cisplatin-associated ototoxicity. It also sets the platform for effective dialogue towards policy formulation and strengthening of health systems in developing countries

In vivo evaluation of an Ultra-fast Disintegrating Wafer matrix : a molecular simulation approach to the ora-mucoadhesivity

The purpose of this study was to design and evaluate the performance of an Ultra-fast Disintegrating Wafer (U-D-WAF) loaded with highly water soluble diphenhydramine hydrochloride (DPH) through the oramucosa of the Large White Pig model. For the first time this work explored the oramucosivity of the U-D-WAF by detailed molecular modeling of the matrix on buccal tissue in order to mechanistically deduce the mucodhesivity. The U-D-WAF was formulated using a blend of hydroxypropylcellulose, poly(acrylic) acid, sodium starch glycolate and β –cyclodextrin in accordance with a Box-Benkhen experimental design for optimization prior to ex vivo permeation and in vivo release studies in the Large White Pig. Molecular simulation studies assess the mucoadhesivity of the U-D-WAF to the oramucosa. A mean Drug Entrapment Efficiency of 72.96 ± 4.32%, disintegration time of 29.33 ± 15.91 s and drug release after 60 s of 86.32 ± 20.37% was recorded. Ex vivo permeation studies revealed cumulative drug permeation of 86.32 ± 20.34% 60 s after onset. In vivo evaluation of the optimized U-D-WAF had a Cmax = 59 μgL−1 approximately 300 s after administration. The ultrafast disintegration of the U-D-WAF matrix with desirable mucoadhesivity in in vitro and in vivo studies makes it suitable for effective and rapid oramucosal drug delivery.The National Research Foundation (NRF) and the Technology Innovation Agency (TIA) of South Africa.http://www.elsevier.com/locate/jddst2018-02-20hj2018Paraclinical Science

A Micro-In-Macro Gastroretentive System for the Delivery of Narrow-Absorption Window Drugs

A micro-in-macro gastroretentive and gastrofloatable drug delivery system (MGDDS), loaded with the model-drug ciprofloxacin, was developed in this study to address the limitations commonly experienced in narrow-absorption window (NAW) drug delivery. The MGDDS, which consists of microparticles loaded in a gastrofloatable macroparticle (gastrosphere) was designed to modify the release of ciprofloxacin, allowing for an increased drug absorption via the gastrointestinal tract. The prepared inner microparticles (1–4 µm) were formed by crosslinking chitosan (CHT) and Eudragit® RL 30D (EUD), with the outer gastrospheres prepared from alginate (ALG), pectin (PEC), poly(acrylic acid) (PAA) and poly(lactic-co-glycolic) acid (PLGA). An experimental design was utilized to optimize the prepared microparticles prior to Fourier Transition Infrared (FTIR) spectroscopy, Scanning Electron Microscopy (SEM) and in vitro drug release studies. Additionally, the in vivo analysis of the MGDDS, employing a Large White Pig model and molecular modeling of the ciprofloxacin-polymer interactions, were performed. The FTIR results determined that the crosslinking of the respective polymers in the microparticle and gastrosphere was achieved, with the SEM analysis detailing the size of the microparticles formed and the porous nature of the MGDDS, which is essential for drug release. The in vivo drug release analysis results further displayed a more controlled ciprofloxacin release profile over 24 h and a greater bioavailability for the MGDDS when compared to the marketed immediate-release ciprofloxacin product. Overall, the developed system successfully delivered ciprofloxacin in a control-release manner and enhanced its absorption, thereby displaying the potential of the system to be used in the delivery of other NAW drugs

Sequential delivery of antibiotics and probiotics employing a dual release mechanism

Antibiotic therapy has been proven to be vital for the treatment of life-threatening bacterial infections. Oral antibiotic therapy, however, results in unwanted side effects such as the intestinal flora destruction, allowing for the colonization of foreign bacteria. This phenomenon results in the occurrence of antibioticassociated diarrhea. Probiotic supplementation has been the choice adjunctive prophylaxis for this condition allowing for the bacterial adhesion of intestinal mucosal binding sites. Probiotic bacteria are, however, susceptible to the bactericidal effects of broad-spectrum antibiotics, resulting in many probiotic formulations being prescribed two hours after the ingestion of the antibiotic formulation. This is, however, not always adhered to, with many patients taking the antibiotic and probiotic concomitantly resulting in the destruction of the probiotic bacteria. This study provides for the design, development, characterization and evaluation of an oral delivery system for the concurrent administration of antibiotics and probiotics employing a dual release mechanism or ‘Dual-Biotic System’. The premise behind the development of this system is to allow for the concurrent administration of antibiotics and probiotics where the probiotic bacteria are only released two hours after the antibiotic, in which time the antibiotic would be absorbed into systemic circulation, preventing physical interaction between the systems and thus preventing bacterial destruction. Amoxicillin was chosen as the model antibiotic in this study due to its spectrum of activity and wide utilization in oral antibiotic therapy

A Novel Intrauterine Device for the Spatio-Temporal Release of Norethindrone Acetate as a Counter-Estrogenic Intervention in the Genitourinary Syndrome of Menopause

The genitourinary syndrome of menopause (GSM) is a widely occurring condition affecting millions of women worldwide. The current treatment of GSM involves the use of orally or vaginally administered estrogens, often with the risk of endometrial hyperplasia. The utilization of progestogens offers a means to counteract the effects of estrogen on the endometrial tissue, decreasing unwanted side effects and improving therapeutic outcomes. In this study, a norethindrone acetate (NETA)-loaded, hollow, cylindrical, and sustained release platform has been designed, fabricated, and optimized for implantation in the uterine cavity as a counter-estrogenic intervention in the treatment of GSM. The developed system, which comprises ethyl cellulose (EC) and polycaprolactone (PCL), has been statistically optimized using a two-factor, two-level factorial design, with the mechanical properties, degradation, swelling, and in vitro drug release of NETA from the device evaluated. The morphological characteristics of the platform were further investigated through scanning electron microscopy in addition to cytocompatibility studies using NIH/3T3 cells. Results from the statistical design highlighted the platform with the highest NETA load and the EC-to-PCL ratio that exhibited favorable release and weight loss profiles. The drug release data for the optimal formulation were best fitted with the Peppas–Sahlin model, implicating both diffusion and polymer relaxation in the release mechanism, with cell viability results noting that the prepared platform demonstrated favorable cytocompatibility. The significant findings of this study firmly establish the developed platform as a promising candidate for the sustained release of NETA within the uterine cavity. This functionality serves as a counter-estrogenic intervention in the treatment of GSM, with the platform holding potential for further advanced biomedical applications

3D Printed, PVA–PAA Hydrogel Loaded-Polycaprolactone Scaffold for the Delivery of Hydrophilic In-Situ Formed Sodium Indomethacin

3D printed polycaprolactone (PCL)-blended scaffolds have been designed, prepared, and evaluated in vitro in this study prior to the incorporation of a polyvinyl alcohol–polyacrylic acid (PVA–PAA) hydrogel for the delivery of in situ-formed sodium indomethacin. The prepared PCL–PVA–PAA scaffold is proposed as a potential structural support system for load-bearing tissue damage where inflammation is prevalent. Uniaxial strain testing of the PCL-blended scaffolds were undertaken to determine the scaffold’s resistance to strain in addition to its thermal, structural, and porosimetric properties. The viscoelastic properties of the incorporated PVA–PAA hydrogel has also been determined, as well as the drug release profile of the PCL–PVA–PAA scaffold. Results of these analyses noted the structural strength, thermal stability, and porosimetric properties of the scaffold, as well as the ability of the PCL–PVA–PAA scaffold to deliver sodium indomethacin in simulated physiological conditions of pH and temperature. The results of this study therefore highlight the successful design, fabrication, and in vitro evaluation of a 3D printed polymeric strain-resistant supportive platform for the delivery of sodium indomethacin

Cisplatin-associated ototoxicity amongst cervical cancer patients: A prospective cohort study in south Africa.

BackgroundConcurrent chemoradiotherapy using weekly cisplatin remains standard of care for locally advanced cervical cancer in Sub-Saharan Africa. While cisplatin remains a popular cancer chemotherapeutic, it has an irreversible ototoxic effect on patients' auditory system. However, there is a paucity of epidemiological information on its extent and severity during cervical cancer treatment. In a region with a high burden of cervical cancer, this has serious consequences for aural intervention and rehabilitation.Methods and findingsUsing a prospective cohort study design, 82 patients with incident cervical cancer, receiving weekly cisplatin chemotherapy (50 mg/m2 body surface) at a tertiary level hospital in KwaZulu-Natal Province of South Africa, underwent audiological assessments at various intervals. We describe the temporal impact of cisplatin exposure on hearing loss, its combined effect with HIV-infection, and estimate ototoxicity incidence in this cohort. The median age was 52 years with Stages IIB (45%) and IIIB (35.4%) cancers being most common. Complaints of reduced hearing sensitivity increased significantly (pConclusionThe findings of this epidemiologic study highlight the temporal course and severity of ototoxicity experienced by cervical cancer patients treated with cisplatin, with greater impact in HIV-positive subgroup, thus underscores the need for audiological monitoring and timely interventions in this cohort

Baseline audiological profiling of South African females with cervical cancer : an important attribute for assessing cisplatin-associated ototoxicity

CITATION: Cervical cancer, J., et al. 2021. Baseline audiological profiling of South African females with cervical cancer : an important attribute for assessing cisplatin-associated ototoxicity. BMC Women’s Health, 21:164, doi:10.1186/s12905-021-01313-5.The original publication is available at https://bmcwomenshealth.biomedcentral.comBackground: Cisplatin is a popular antineoplastic agent used to treat cervical cancer in women from low and middle-income countries. Cisplatin treatment is associated with ototoxicity, often resulting in hearing loss. In light of this, it is crucial to conduct baseline audiological assessments prior to treatment initiation in order to evaluate the extent of cisplatin-associated-ototoxicity. Additionally, the identification of inherent risk factors and hearing patterns in specific patient cohorts is needed, especially in South Africa, a middle-income country characterized by the quadruple burden of disease (Human Immunodeficiency Virus (HIV), Tuberculosis (TB), Diabetes and Hypertension). Methods: This study aimed to describe a profile of risk factors and hearing in a cohort of females with cervical cancer before cisplatin treatment commenced. A descriptive study design that included 82 cervical cancer patients, who underwent audiological evaluation prescribed for ototoxicity monitoring was conducted. Results: All participants (n = 82) presented with risk factors (diabetes, hypertension, HIV, and antiretroviral therapy) for cisplatin ototoxicity and/or pre-existing sensorineural hearing loss. High-frequency tinnitus was the most common otological symptom experienced by 25 (31%) participants. Fifty-nine (72%) participants presented with normal hearing, twenty-two (27%) with a sensorineural hearing loss, and 36% were diagnosed with mild hearing loss. Abnormal Distortion Product Otoacoustic Emissions (DPOAE) findings were obtained bilaterally in two participants (2.4%), in the right ear only of another two (2.4%) participants and the left ear of three participants (3.7%). Most participants (94%) had excellent word recognition scores, demonstrating an excellent ability to recognize words within normal conversational levels under optimal listening conditions. Age was significantly associated with hearing loss at all thresholds. Among the co-morbidities, an HIV positive status significantly triggered hearing loss, especially at higher frequencies. Conclusion: This study demonstrated that South African females with cervical cancer present with various co-morbidities, which may predispose them to develop cisplatin-associated -ototoxic hearing loss. Identification of these comorbidities and hearing loss is essential for the accurate monitoring of cisplatin toxicities. Appropriate management of these patients is pivotal to reduce the adverse effects that hearing impairment can have on an individual’s quality of life and to facilitate informed decision-making regarding the commencement of cisplatin chemotherapy.https://bmcwomenshealth.biomedcentral.com/articles/10.1186/s12905-021-01313-5Publisher's versio

Drug Delivery Strategies for Antivirals against Hepatitis B Virus

Chronic hepatitis B virus (HBV) infection poses a significant health challenge due to associated morbidity and mortality from cirrhosis and hepatocellular cancer that eventually results in the breakdown of liver functionality. Nanotechnology has the potential to play a pivotal role in reducing viral load levels and drug-resistant HBV through drug targeting, thus reducing the rate of evolution of the disease. Apart from tissue targeting, intracellular delivery of a wide range of drugs is necessary to exert a therapeutic action in the affected organelles. This review encompasses the strategies and techniques that have been utilized to target the HBV-infected nuclei in liver hepatocytes, with a significant look at the new insights and most recent advances in drug carriers and their role in anti-HBV therapy

In vitro and in vivo evaluation of an oral multi-layered multi-disk tablet for specialized chronotherapeutic drug delivery

Chronotherapeutic disorders such as hypertension, cardiovascular disease and asthma commonly involve the use of controlled zero-order release formulations. Ideally, the required drug should be released at predetermined rates with two or more pulses released from the dosage form. This ultimately exposes the patient to drug only when required, reducing the number of dosages, reducing side-effects and increasing patient compliance. The aim of this research was to evaluate two Multi-Layered Multi-Disk Tablet (MLMDT) systems incorporating drug-loaded disks enveloped by three polymeric layers. The model drugs used for each system were theophylline and diltiazem hydrochloride. The proposed chronotherapeutic system was designed to provide a lag phase and then two pulses of drug release separated by a ‘switch-off’ phase. In vitro drug release analysis revealed that the MLMDT generated a lag phase or a ‘switch-off’ phase followed by two pulses of drug release over the evaluated 24 h period. In vivo testing was undertaken using a Large White Pig Model, where concentration analysis from the evaluated conventional products revealed increasing plasma concentrations up to 2 h followed by a steady decline in concentration while the developed MLMDT displayed two pulse prolonged drug release profile separated by a switch-off phase.The National Research Foundation (NRF) of South Africa.http://www.elsevier.com/locate/jddst2019-06-01hj2019Paraclinical Science