Idarubicin-loaded ONCOZENE drug-eluting embolic agents for chemoembolization of hepatocellular carcinoma: in vitro loading and release and in vivo pharmacokinetics

Transarterial Chemoembolization with Epirubicin-Loaded Microspheres for Hepatocellular Carcinoma: A Prospective, Single-Arm, Multicenter, Phase 2 Study (STOPPER Trial)

PURPOSE

While the role of drug-eluting beads transarterial chemoembolization (DEB-TACE) for hepatocellular carcinoma (HCC) is established, questions regarding appropriate bead size for use in patients remain. This trial evaluated the effectiveness and safety of DEB-TACE using small-size (≤ 100 μm) microspheres loaded with epirubicin.

MATERIALS AND METHODS

This prospective, single-arm, multicenter study enrolled patients diagnosed with HCC who underwent DEB-TACE using 40 (range, 30-50), 75 (range, 60-90), or 100 (range, 75-125) μm epirubicin-loaded microspheres (TANDEM microspheres, Varian Medical). Bead size was at the discretion of treating physicians and based on tumor size and/or vascular structure. The primary outcome measure was 6-month objective response rate (ORR). Secondary outcome measures were 30-day and 3-month ORR, time to tumor progression and extrahepatic spread, proportion of progression-free survival and overall survival (OS) at one year, and incidence of treatment-associated adverse events.

RESULTS

Data from 108 patients from ten centers was analyzed. Six-month ORR was 73.3 and 71.3% based on European association for the study of the liver (EASL) and modified response evaluation criteria in solid tumors (mRECIST) criteria, respectively. Thirty-day ORR was 79.6% for both EASL and mRECIST criteria with 3-month ORR being 80.0 and 81.0%, respectively, for each criteria. One-year PPF and OS rate were 60.3 and 94.3%. There was a total of 30 SAEs reported to be likely to definitely associated with microsphere (n = 9), epirubicin (n = 9), or procedure (n = 12) with none resulting in death.

CONCLUSION

DEB-TACE using epirubicin-loaded small-sized (≤ 100 μm) microspheres demonstrates promising local tumor control and acceptable safety in patients with HCC.

TRIAL REGISTRATION

Clinicaltrials.gov NCT03113955; registered April 14, 2017. Trial Registration Clinicaltrials.gov NCT03113955; registered April 14, 2017.

LEVEL OF EVIDENCE

2, Prospective, Non-randomized, Single-arm, study.

Recent advances and applications of microspheres and nanoparticles in transarterial chemoembolization for hepatocellular carcinoma

Transarterial chemoembolization (TACE) is a recommended treatment for patients suffering from intermediate and advanced hepatocellular carcinoma (HCC). As compared to the conventional TACE, drug-eluting bead TACE demonstrates several advantages in terms of survival, treatment response, and adverse effects. The selection of embolic agents is critical to the success of TACE. Many studies have been performed on the modification of the structure, size, homogeneity, biocompatibility, and biodegradability of embolic agents. Continuing efforts are focused on efficient loading of versatile chemotherapeutics, controlled sizes for sufficient occlusion, real-time detection intra- and post-procedure, and multimodality imaging-guided precise treatment. Here, we summarize recent advances and applications of microspheres and nanoparticles in TACE for HCC. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

Anticancer Drugs for Intra-Arterial Treatment of Colorectal Cancer Liver Metastases: In-Vitro Screening after Short Exposure Time

To treat colorectal liver metastases, intra-arterial chemotherapies may complete therapeutic arsenal. Drugs using intra-arterially are very heterogeneous. The aim of this study was to select the most efficient drug on a panel of colorectal cancer (CRC) cell lines (Caco-2, HCT 116, HT 29, SW 48, SW 480, SW 620) exposed for 30 min to 12 cytotoxic agents (doxorubicin, epirubicin, idarubicin, 5-FU, raltitrexed, gemcitabine, cisplatin, oxaliplatin, mitomycin C, irinotecan, streptozocin, paclitaxel) at different concentrations. The effect on cell viability was measured using the WST-1 cell viability assay. For each drug and cell line, the IC₅₀ and IC₉₀ were calculated, which respectively correspond to the drug concentration (mg/mL) required to obtain 50% and 90% of cell death. We also quantified the cytotoxic index (CyI₉₀ = C Max/IC₉₀) to compare drug efficacy. The main findings of this study are that idarubicin emerged as the most cytotoxic agent to most of the tested CRC cell lines (Caco-2, HT29, HCT116, SW620 and SW480). Gemcitabine seemed to be the most efficient chemotherapy for SW48. Interestingly, the most commonly used cytotoxic agents in the systemic and intra-arterial treatment of colorectal liver metastasis (CRLM) (oxaliplatin, 5-FU, irinotecan) showed very limited cytotoxicity to all the cell lines.

Transarterial Chemoembolization of Hepatocellular Carcinoma with Oncozene Microspheres: An Initial, Short-Term Clinical Experience-A Retrospective, Matched, Comparison Study

Background: The purpose of this study is to describe a single institution's experience using Oncozene (OZ) microspheres for transarterial chemoembolization (OZ-TACE) of hepatocellular carcinoma (HCC), and to compare tolerability, safety, short-term radiographic tumor response, progression-free survival (PFS), and overall survival (OS) of these procedures to TACE (LC-TACE) performed with LC beads (LC). Methods: A retrospective, matched cohort study of patients undergoing DEB-TACE (drug-eluting bead transarterial chemoembolization) with OZ or LC was performed. The cohort comprised 23 patients undergoing 29 TACE with 75 or 100 μm OZ and 24 patients undergoing 29 TACE with 100-300 μm LC. Outcome measures were changes in liver function tests, complications, treatment tolerability, short-term radiographic tumor response according to modified RECIST criteria for HCC, PFS, and 1-year OS. The Mann-Whitney U test, Fisher exact test, and log rank test were used to compare the groups. Results: The BCLC or Child-Pugh scores were similar between the OZ and LC group. However, the two groups differed with respect to the etiology of background cirrhosis (p = 0.02). All other initial demographic and tumor characteristics were similar between the two groups. OZ-TACE used less doxorubicin per treatment compared to LC-TACE (median 50 vs. 75 mg; p = 0.0005). Rates of pain, nausea, and postembolization syndrome were similar, irrespective of the embolic agent used. OZ-TACE resulted in an overall complication rate comparable to LC-TACE (20.7% vs. 10.3%; p = 0.47). LC-TACE resulted in a higher percent increase in total bilirubin on post-procedure day 1 (median 18.8 vs. 0%; p = 0.05), but this difference resolved at 1 month. Both OZ-TACE and LC-TACE resulted in similar complete (31% vs. 24%) and objective (66% vs. 79%) target lesion response rates on 1-month post-TACE imaging. Both OZ-TACE and LC-TACE had similar median progression-free survival (283 vs. 209 days; p = 0.14) and 1-year overall survival rates (85% vs. 76%; p = 0.30). Conclusion: With a significantly reduced dose of doxorubicin, TACE performed with Oncozene microspheres in a heterogeneous patient population is well-tolerated, safe, and produces a similar radiological response and survival rate when compared to LC Bead TACE.

The short-term safety and efficacy of TANDEM microspheres of various sizes and doxorubicin loading concentrations for hepatocellular carcinoma treatment

Drug-eluting bead transarterial chemoembolization (DEB-TACE) is the most common treatment for unresectable hepatocellular carcinoma (HCC). However, the effect of drug loading concentration and microsphere size on treatment outcomes remains unclear. This retrospective study compares the outcomes of 87 HCC patients who underwent DEB-TACE with half-loaded or full-loaded doxorubicin (maximum capacity 50 mg/mL) in 75-µm or 100-µm microspheres. Treatment with 100-μm microspheres resulted in significantly lower rates of procedure-related complications (6.6% vs. 26.9%; P < 0.05), post-embolization syndrome (32.8% vs. 61.5%, P < 0.05), SIR complications (32.8% vs. 61.5%; P < 0.01) and adverse events involving abdominal pain (19.7% vs. 42.3%; P < 0.05). Half-load doxorubicin microspheres resulted in greater treatment response (OR, 4.00; 95% CI 1.06–15.13; P, 0.041) and shorter hospital stays (OR, − 1.72; 95% CI − 2.77–0.68; P, 0.001) than did microspheres loaded to full capacity. Stratified analysis further showed that patients treated with 100-μm half-load doxorubicin microspheres had a higher CR (63.6% vs 18.0%) and ORR (90.9 vs 54.0%) and a shorter hospital stay (1.6 ± 1.3 vs 4.2 ± 2.3 days) than did those treated with full-load microspheres (P < 0.05). Thus, the drug-loading concentration of microspheres in DEB-TACE should be carefully considered.

Optimized Loading of Idarubicin in CalliSpheres® Drug-Eluting Beads and Characterization of Release Profiles and Morphological Properties

This study aimed to investigate the idarubicin loading method, compatible stability with contrast agent, release profiles, and morphological properties of 50-150, 100-300, and 300-500 μm CalliSpheres^®. The amounts of idarubicin added, loading medium, loading condition, and drug concentration were investigated as factors influencing drug loading efficiency. The drug loading rate was negatively correlated with the amount drug added and diameter of CalliSpheres^® and positively correlated with the drug concentration. Compared to loading in purified water and incubation at room temperature, 5% glucose, heating, and ultrasound could accelerate drug loading. The idarubicin loading efficiency was above 95% after 10 min for all three CalliSpheres^® with the optimized method of adding 20 mg of idarubicin at a concentration of 2 mg/mL and incubating at room temperature. The drug leak rate was under 1% within 8 h after mixing with iopamidol. Drug release tests indicated the sustained-release performance of CalliSpheres^®, and the time to reach 75% of the release plateau level was 8, 26, and 51 min for 50-150, 100-300, and 300-500 μm CalliSpheres^®, respectively. After idarubicin loading, the diameters increased by 12%, 36%, and 38% for 50-150, 100-300, and 300-500 μm CalliSpheres^®, respectively, and the surface of CalliSpheres^® was observed to become smoother than that before drug loading. All three CalliSpheres^® presented satisfactory loading efficiency with the optimized method, as well as proper compatible stability and sustained release performance. Among them, 100-300 μm CalliSpheres^® are recommended.

Timeline of Translational Formulation Technologies for Cancer Therapy: Successes, Failures, and Lessons Learned Therefrom

Over the past few decades, the field of cancer therapy has seen a significant change in the way in which formulations are designed and developed, resulting in more efficient products that allow us to ultimately achieve improved drug bioavailability, efficacy, and safety. However, although many formulations have entered the market, many others have fallen by the wayside leaving the scientific community with several lessons to learn. The successes (and failures) achieved with formulations that have been approved in Europe and/or by the FDA for the three major types of cancer therapy (peptide-based therapy, chemotherapy, and radiotherapy) are reviewed herein, covering the period from the approval of the first prolonged-release system for hormonal therapy to the appearance of the first biodegradable microspheres intended for chemoembolization in 2020. In addition, those products that have entered phase III clinical trials that have been active over the last five years are summarized in order to outline future research trends and possibilities that lie ahead to develop clinically translatable formulations for cancer treatment.

Clinical Pharmacokinetics and Pharmacodynamics of Transarterial Chemoembolization and Targeted Therapies in Hepatocellular Carcinoma

The management of hepatocellular carcinoma (HCC) is based on a multidisciplinary decision tree. Treatment includes loco-regional therapy, mainly transarterial chemoembolization, for intermediate-stage HCC and systemic therapy with oral tyrosine kinase inhibitors (TKIs) for advanced HCC. Transarterial chemoembolization involves hepatic intra-arterial infusion with either conventional procedure or drug-eluting-beads. The aim of the loco-regional procedure is to deliver treatment as close as possible to the tumor both to embolize the tumor area and to enhance efficacy and minimize systemic toxicity of the anticancer drug. Pharmacokinetic studies applied to transarterial chemoembolization are rare and pharmacodynamic studies even rarer. However, all available studies lead to the same conclusions: use of the transarterial route lowers systemic exposure to the cytotoxic drug and leads to much higher tumor drug concentrations than does a similar dose via the intravenous route. However, reproducibility of the procedure remains a major problem, and no consensus exists regarding the choice of anticancer drug and its dosage. Systemic therapy with TKIs is based on sorafenib and lenvatinib as first-line treatment and regorafenib and cabozantinib as second-line treatment. Clinical use of TKIs is challenging because of their complex pharmacokinetics, with high liver metabolism yielding both active metabolites and their common toxicities. Changes in liver function over time with the progression of HCC adds further complexity to the use of TKIs. The challenges posed by TKIs and the HCC disease process means monitoring of TKIs is required to improve clinical management. To date, only partial data supporting sorafenib monitoring is available. Results from further pharmacokinetic/pharmacodynamic studies of these four TKIs are eagerly awaited and are expected to permit such monitoring and the development of consensus guidelines.

Idarubicin-Loaded ONCOZENE Drug-Eluting Bead Chemoembolization in a Rabbit Liver Tumor Model: Investigating Safety, Therapeutic Efficacy, and Effects on Tumor Microenvironment

PURPOSE

To investigate toxicity, efficacy, and microenvironmental effects of idarubicin-loaded 40-μm and 100-μm drug-eluting embolic (DEE) transarterial chemoembolization in a rabbit liver tumor model.

MATERIALS AND METHODS

Twelve male New Zealand White rabbits with orthotopically implanted VX2 liver tumors were assigned to DEE chemoembolization with 40-μm (n = 5) or 100-μm (n = 4) ONCOZENE microspheres or no treatment (control; n = 3). At 24-72 hours postprocedurally, multiparametric magnetic resonance (MR) imaging including dynamic contrast-enhanced (DCE), diffusion-weighted imaging (DWI), and biosensor imaging of redundant deviation in shifts (BIRDS) was performed to assess extracellular pH (pHe), followed by immediate euthanasia. Laboratory parameters and histopathologic ex vivo analysis included fluorescence confocal microscopy and immunohistochemistry.

RESULTS

DCE MR imaging demonstrated a similar degree of devascularization of embolized tumors for both microsphere sizes (mean arterial enhancement, 8% ± 12 vs 36% ± 51 in controls; P = .07). Similarly, DWI showed postprocedural increases in diffusion across the entire lesion (apparent diffusion coefficient, 1.89 × 10^-3 mm²/s ± 0.18 vs 2.34 × 10^-3 mm²/s ± 0.18 in liver; P = .002). BIRDS demonstrated profound tumor acidosis at baseline (mean pHe, 6.79 ± 0.08 in tumor vs 7.13 ± 0.08 in liver; P = .02) and after chemoembolization (6.8 ± 0.06 in tumor vs 7.1 ± 0.04 in liver; P = .007). Laboratory and ex vivo analyses showed central tumor core penetration and greater increase in liver enzymes for 40-μm vs 100-μm microspheres. Inhibition of cell proliferation, intratumoral hypoxia, and limited idarubicin elution were equally observed with both sphere sizes.

CONCLUSIONS

Noninvasive multiparametric MR imaging visualized chemoembolic effects in tumor and tumor microenvironment following DEE chemoembolization. Devascularization, increased hypoxia, coagulative necrosis, tumor acidosis, and limited idarubicin elution suggest ischemia as the predominant therapeutic mechanism. Substantial size-dependent differences indicate greater toxicity with the smaller microsphere diameter.

Survival Outcomes of Very Small Drug-Eluting Beads Used in Chemoembolization of Unresectable Hepatocellular Carcinoma

PURPOSE

To assess the safety and efficacy of transarterial chemoembolization using a 75-μm drug-eluting embolic (DEE) in patients with unresectable hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

The medical records of 109 patients with a mean age of 64.1 years (range 85-49) treated for unresectable HCC between November 2013 and August 2016 with transarterial chemoembolization using a 75-μm DEE were retrospectively reviewed. Patients who had prior therapy for HCC were excluded. Child-Pugh A patients and Barcelona Clinic Liver Cancer stages A/B patients constituted 68.8% and 65.1% of the patients, respectively. The mean size of the index tumors was 5.8 cm (range 18.5-1.2) with 42 (39%) patients with central tumors around the porta-hepatis region. Portal vein invasion was seen in 10 (9.2%) patients. Tumor response was categorized according to the modified Response Evaluation Criteria in Solid Tumors 1.1, and the toxicity profile was assessed using Common Terminology Criteria for Adverse Events, version 4.03.

RESULTS

At 1-month follow-up, complete response, objective response, and disease control was seen in 23%, 66%, and 90%, respectively. The median progression-free survival was 11.2 months. The median overall survival was 25.1 months (33.4 months for Child-Pugh A and 28.2 months for Barcelona Clinic Liver Cancer stages A/B), and transplant-free survival was 21.3 months. The 6-, 12-, and 24-month survivals were 91.7%, 75.5%, and 50.5%, respectively. Grade 3 toxicity was seen in 1.8% of the patients; no grade 4 or 5 toxicity was reported.

CONCLUSIONS

Transarterial chemoembolization using 75-μm DEE is safe and efficacious in the treatment of HCC.

Advances in Biomaterials and Technologies for Vascular Embolization

Minimally invasive transcatheter embolization is a common nonsurgical procedure in interventional radiology used for the deliberate occlusion of blood vessels for the treatment of diseased or injured vasculature. A wide variety of embolic agents including metallic coils, calibrated microspheres, and liquids are available for clinical practice. Additionally, advances in biomaterials, such as shape-memory foams, biodegradable polymers, and in situ gelling solutions have led to the development of novel preclinical embolic agents. The aim here is to provide a comprehensive overview of current and emerging technologies in endovascular embolization with respect to devices, materials, mechanisms, and design guidelines. Limitations and challenges in embolic materials are also discussed to promote advancement in the field.

Super-Selective Transarterial Chemoembolization with Doxorubicin-Loaded Drug-Eluting Beads Sized Below and Above 100 Microns in Hepatocellular Carcinoma: A Comparative Study

Objectives To compare efficacy and safety of super-selective DEB-TACE with doxorubicin-loaded microspheres sized below and above 100 microns for treatment of hepatocellular carcinoma (HCC). Material and methods All consecutive patients with HCC who underwent DEB-TACE were included in this retrospective study. Regarding to microsphere size (>100 microns or <100 microns), patients were determined as Group A (n = 28) and Group B (n = 30), respectively. Results Of the 58 patients (78% males), no statistically significant difference was found between the two groups in terms of age and gender (P = 0.388, P = 0.888, respectively). There were no significant differences between the two groups in terms of BCLC stages, presence of chronic liver disease, and Child-Pugh classes (P = 0.593, P = 0.081, P = 0.391, respectively). Although statistically insignificant, median overall survival (19 months vs 32 months, P = 0.190) and median progression-free survival (13 months vs 20 months (P = 0.574) were longer and 1-3-years objective response rates (7.40% vs 23.33%, P = 0.330) were higher in Group B than in Group A, respectively. No mortality or major complications were observed. Grade I/ II adverse events were detected in all patients. Transient elevations in liver function tests (Grade III adverse events) were similar in both groups (3.57% vs 3.33%; P = 0.980). Conclusion Super-selective DEB-TACE with doxorubicin-loaded microspheres sized <100 microns is an effective and safe method for the HCC treatment. Objective response rates are higher and survival durations are longer after DEB-TACE performed with doxorubicin-loaded microspheres sized below 100 microns. Keywords Chemoembolization Doxorubicin Microspheres Drug-eluting beads Hepatocellular carcinoma

Transarterial Chemoembolization of Hepatocellular Carcinoma with Idarubicin-Loaded Tandem Drug-Eluting Embolics

: Objective: To describe the responses, toxicities and outcomes of HCC patients treated by transarterial chemoembolization (TACE) using idarubicin-loaded TANDEM beads. Materials and Methods: Seventy-two consecutive patients (mean age: 71 years (58-84 years)) with HCC were treated by TACE using idarubicin-loaded TANDEM in a first line, over a five-year period. Most patients (89%) had liver cirrhosis classified as Child-Pugh A (90%). BCLC B classification applied in 85% of cases. Baseline tumor burden was limited to one to three nodules in 92% of cases, unilobar in 88% cases, with a median tumor diameter of 55 mm (range: 13-150 mm). Toxicity was assessed using NCI CTC AE v4.0. Response was assessed using mRECIST criteria. Time-to-treatment failure (TTTF) and overall survival (OS) were also calculated based on Kaplan-Meier method. Result: Of 141 TACE sessions performed with bead sizes of 100 and 75 µm in 42 (29.8%) and 99 (70.2%) sessions, respectively. In 78% of all TACE sessions, the full dose of idarubicin-loaded beads was injected. Grade 3-4 AE were observed after 73 (52%) sessions, most of them being biological. Multi-organ failure was observed three days after the first TACE in a Child B patients, unfortunately leading to death. Overall, the best objective response rate (ORR) was 65%. Median follow-up lasted 14.3 months (95% CI: 11.2-18.8 months). Median TTTF and OS were 14.4 months (95% CI: 7.2-24.6 months) and 34.6 months (95% CI: 24.7-not reached) respectively. Conclusion: In this retrospective study involving well-selected HCC patients, high ORR and long TTTF and OS are observed after TACE using idarubicin-loaded TANDEM. A randomized trial is needed.

An In Vitro Evaluation of Four Types of Drug-Eluting Embolics Loaded with Idarubicin

PURPOSE

This study compared loading, elution, and stability of drug-eluting embolic beads (DEBs) loaded with idarubicin.

MATERIALS AND METHODS

DC Bead (100-300 μm), HepaSphere (30-60 μm), LifePearl (200 μm), and Tandem (100 μm) DEBs were loaded with 5 mg/mL idarubicin. Loading, elution, diameter changes, loading stability over 2 weeks in storage, and time in suspension were determined for each of the DEBs.

RESULTS

Loading of more than 99% of idarubicin was achieved within 15 minutes for LifePearl, DC Bead, and Tandem beads. LifePearl, DC Bead, HepaSphere, and Tandem beads eluted 75% of the total idarubicin released in 13, 24, 42, and 91 minutes, respectively. In vitro elution was completed in 2 hours with 73% ± 3%, 74% ± 3%, 65% ± 6%, and 7% ± 0% of the loaded idarubicin eluted for LifePearl, DC Bead, HepaSphere, and Tandem, respectively. Statistically significant differences were observed at every time point between at least 2 of the products. Overall, in vitro idarubicin elution was rapid and nearly complete for LifePearl, DC Bead, and HepaSphere beads but was minimal and slow from Tandem beads. The average diameter of DEBs after loading was reduced by 5% for LifePearl, whereas it was increased by 9% and 1% for DC Bead and Tandem, respectively. After loading, time in suspension was 11 ± 4 and 10 ± 2 minutes for LifePearl and HepaSphere, respectively, whereas DC Bead and Tandem beads were held in suspension for greater than 20 minutes.

CONCLUSIONS

Although all 4 DEBs loaded idarubicin within 15 minutes with minimal changes in diameter, the elution amounts, rates of release, and time in suspension varied.

Blood and urine analyses after radioembolization of liver malignancies with [166Ho]Ho-acetylacetonate-poly(l-lactic acid) microspheres

BACKGROUND

[¹⁶⁶Ho]Ho-acetylacetonate-poly(L-lactic acid) microspheres were used in radioembolization of liver malignancies by intra-arterial administration. The primary aim of this study was to assess the stability and biodistribution of these microspheres.

MATERIALS AND METHODS

Peripheral blood and urine samples were obtained from two clinical studies. Patient and in vitro experiment samples were analyzed using inductively coupled plasma mass spectrometry (ICP-MS), gamma-ray spectroscopy, light microscopy, Coulter particle counting, and high performance liquid chromatography (HPLC).

RESULTS

The median percentage holmium compared to the total amount injected into the hepatic artery was 0.19% (range 0.08-2.8%) and 0.32% (range 0.03-1.8%) in the 1 h blood plasma and 24 h urine, respectively. Both the blood plasma and urine were correlated with the neutron irradiation exposure required for [¹⁶⁶Ho]Ho-AcAc-PLLA microsphere production (ρ = 0.616, p = 0.002). After a temporary interruption of the phase 2 clinical study, the resuspension medium was replaced to precipitate [¹⁶⁶Ho]Ho³⁺ pre-administration using phosphate. The in vitro near-maximum neutron irradiation experiments showed significant [¹⁶⁶Ho]Ho-AcAc-PLLA microsphere damage.

CONCLUSION

The amount of holmium in the peripheral blood and urine samples after [¹⁶⁶Ho]Ho-AcAc-PLLA microsphere intrahepatic infusion was low. A further decrease was observed after reformulation of the resuspension solution but minimization of production damage is necessary.

DEB-TACE: a standard review

Drug-eluting bead transarterial chemoembolization (DEB-TACE) is a relative new endovascular treatment based on the use of microspheres to release chemotherapeutic agents within a target lesion with controlled pharmacokinetics. This aspect justifies the immediate success of DEB-TACE, that nowadays represents one of the most used treatments for unresectable hepatocellular carcinoma. However, there is no consensus about the choice of the best embolotherapy technique. In this review, we describe the available microspheres and report the results of the main comparative studies, to clarify the role of DEB-TACE in the hepatocellular carcinoma management. We underline that there is no evidence about the superiority of DEB-TACE over conventional TACE in terms of efficacy, but there may be some benefits with respect to safety especially with the improvement of new technologies.

Liver chemoembolization of hepatocellular carcinoma using TANDEM® microspheres

Transarterial chemoembolization (TACE) combines intra-arterial delivery of a chemotherapeutic agent with selective embolization to obtain a synergistic effect. TACE is recognized as the standard treatment of hepatocellular carcinoma patients at an intermediate stage. If conventional TACE, defined as the injection of an emulsion of a drug with ethiodized oil, still has a role to play, the development of drug-eluting beads has allowed many improvements and optimization of the technique. TANDEM^® microspheres are second-generation drug-loadable microspheres. This device raised a special interest due to its tightly calibrated spherical microspheres, with small sizes down to 40 μm available. In this review, we describe the technical characteristics of these microspheres, analyze the scientific literature and hypothesize on the future perspectives.

Short-term efficacy of transarterial chemoembolization with epirubicin-loaded superabsorbent polymer microspheres for hepatocellular carcinoma: comparison with conventional transarterial chemoembolization

PURPOSE

This study aimed to compare the short-term efficacy of transarterial chemoembolization (TACE) with epirubicin-loaded superabsorbent polymer embolics (SAP) and conventional TACE in TACE-naïve patients with unresectable hepatocellular carcinoma (HCC).

METHODS

Fifty consecutive patients (mean age, 72.8 years; hepatitis C, 46%; BCLC-A or B, 52% or 48%) treated with TACE with SAP during 2013-2015 and 55 consecutive patients (mean age, 71.8 years; hepatitis C, 40%; BCLC-A or B, 51% or 49%) treated with conventional TACE during 2011-2013 were evaluated. Safety evaluations were based on CTCAE ver. 4.0. Short-term efficacies, i.e., at 1 month after TACE, were assessed using the European Association for the Study of the Liver criteria. Overall survival rates were calculated using the Kaplan-Meier method. Short-term response markers were analyzed by univariate and multivariate analyses.

RESULTS

There was no significant difference in the incidence of any grade of adverse events. The objective response rates were 50% and 62% in patients treated with TACE with SAP and with conventional TACE, respectively (P = 0.358). The overall survival rates were not significantly different (P = 0.810); the 1-year survival rates and the median survival time of the patients treated with TACE with SAP and with conventional TACE were 76% and 74%, and 18 months and 21 months, respectively. Overall survival was related to the short-term response. An alpha-fetoprotein level <1,000 ng/mL was a significant short-term response marker on multivariate analysis.

CONCLUSIONS

For TACE-naïve patients, TACE with SAP and conventional TACE had comparable safety and short-term efficacies.

Preparation and characterisation of vandetanib-eluting radiopaque beads for locoregional treatment of hepatic malignancies

Since their introduction around a decade ago, embolic drug-eluting beads (DEBs) have become a well-established treatment option for the locoregional transarterial treatment of hepatic malignancies. Despite this success, the therapy is seen to be limited by the choice of drug and more effective options are therefore being sought. These include the small molecule multi-tyrosine kinase inhibitors (MTKi), which exert an anti-angiogenic and anti-proliferative effect that could be highly beneficial in combating some of the unwanted downstream consequences of embolization. Vandetanib is an MTKi which acts against such targets as vascular endothelial growth factor receptor (VEGFR) and epithelial growth factor receptor (EGFR) and has demonstrated modest activity against hepatocellular carcinoma (HCC), albeit with some dose-limiting cardiac toxicity. This makes this compound an interesting candidate for DEB-based locoregional delivery. In this study we describe the preparation and characterisation of vandetanib DEBs made from DC Bead™ and its radiopaque counterpart, DC Bead LUMI™. Drug loading was shown to be dependent upon the pH of the drug loading solution, as vandetanib has multiple sites for protonation, with the bead platform also having a fundamental influence due to differences in binding capacities and bead shrinkage effects. Fourier transform infrared (FTIR) spectroscopy and energy dispersive X-ray (EDX) Spectroscopy confirmed drug interaction is by ionic interaction, and in the case of the radiopaque DEB, the drug is distributed uniformly inside the bead and contributes slightly to the overall radiopacity by virtue of a bromine atom on the vandetanib structure. Drug release from both bead platforms is controlled and sustained, with a slightly slower rate of release from the radiopaque bead due to its more hydrophobic nature. Vandetanib DEBs therefore have suitable characteristics for intra-arterial delivery and site-specific sustained release of drug into liver tumours.

Interventional oncology for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer and is increasing in incidence. The overall prognosis of patients with liver cancer is poor. The Barcelona Clinic Liver Cancer (BCLC) classification in 5 stages is endorsed by European Association for the Study of the Liver (EASL) and American Association for the Study of Liver Disease (AASLD). This classification is recommended for treatment allocation. Because a small proportion of patients are suitable for curative surgical treatment, various locoregional therapies are widely used to manage patients with HCC. The image-guided therapies, also called interventional radiology or interventional oncology (IO) techniques consisted in percutaneous or endovascular approach. This article reviews the different IO treatments available in HCC patients and the strength of the data.

Pharmacokinetics, Safety, and Efficacy of Chemoembolization with Doxorubicin-Loaded Tightly Calibrated Small Microspheres in Patients with Hepatocellular Carcinoma

PURPOSE

This study examines safety, efficacy, and pharmacokinetics of chemoembolization with loadable microspheres ≤100 μm for hepatocellular carcinoma.

MATERIALS AND METHODS

A pilot safety study was performed in 19 patients with size and dose escalation and then 52 patients were enrolled prospectively and randomly assigned to chemoembolization with TANDEM™ loaded with 150 or 100 mg of doxorubicin.

RESULTS

The mean diameter of the tumors was 7.28 ± 2.09 cm (range 4-12) and distribution dominant/multiple 51.9/48.1 %. Child A/B distribution was 32/20 (61.5/38.5 %) and etiology HBV/HCV/HBV/HCV-hemochromatosis was 61.6/9.6/9.6/15.4 %. Twenty-five patients were assigned in the low and 27 in the high loading group. There was 1.92 % thirty-day mortality due to lesion rupture. Biliary damage was seen in 3 patients (5.7 %) in the high loading. Mean maximum plasma concentration of doxorubicin C max ± SD was 284.9 ± 276.2 ng/mL for the high and 108.5 ± 77.6 ng/mL for the low loading (p < 0.001). According to m-RECIST overall objective response after two sessions reached 61.22 and 63.82 % at 6 months. Notably, complete target lesion response (CR) after the second session was observed in 28.57 % and maintained in 23.40 % at 6 months. No statistical differences in the local response rates were observed between the two loading groups. Overall survival (OS) at 6 months, 1 , 2, and 3 years was 98.08, 92.3, 88.46, and 82.6 %, respectively. OS and Progression-Free Survival did not demonstrate statistical significance between the two loading groups.

CONCLUSION

Initial evidence shows that (a) TANDEM™ achieves high rates of local response and mid-term survival, (b) high loading provides no clinical benefit and is associated with biliary toxicity.

Improved stability of lipiodol-drug emulsion for transarterial chemoembolisation of hepatocellular carcinoma results in improved pharmacokinetic profile: Proof of concept using idarubicin

OBJECTIVES

To investigate the relationship between the improved stability of an anticancer drug-lipiodol emulsion and pharmacokinetic (PK) profile for transarterial chemoembolisation (TACE) of hepatocellular carcinoma (HCC).

METHODS

The stability of four doxorubicin- or idarubicin-lipiodol emulsions was evaluated over 7 days. PK and clinical data were recorded after TACE with the most stable emulsion in eight unresectable HCC patients, after institutional review board approval.

RESULTS

The most stable emulsion was the one that combined idarubicin and lipiodol (1:2 v:v). At 7 days, the percentages of aqueous, persisting emulsion and oily phases were 50-0-50, 33-0-67, 31-39-30, and 10-90-0 for the doxorubicin-lipiodol (1:1 v:v), doxorubicin-lipiodol (1:2 v:v), idarubicin-lipiodol (1:1 v:v), and the idarubicin-lipiodol (1:2 v:v) emulsion, respectively. After TACE, mean idarubicin Cmax and AUC0-24h were 12.5 ± 9.4 ng/mL and 52 ± 16 ng/mL*h. Within 24 h after injection, 40% of the idarubicin was in the liver, either in vessels, tumours, or hepatocytes. During the 2 months after TACE, no clinical grade >3 adverse events occurred. One complete response, five partial responses, one stabilisation, and one progression were observed at 2 months.

CONCLUSION

This study showed a promising and favourable PK and safety profile for the idarubicin-lipiodol (1:2 v:v) emulsion for TACE.

KEY POINTS

• Transarterial chemoembolisation (TACE) regimens that improve survival in hepatocellular carcinoma are needed. • Improved emulsion stability for TACE resulted in a favourable pharmacokinetic profile. • Preliminary safety and efficacy data for the idarubicin-lipiodol emulsion for TACE were encouraging.