Evaluation of Physicochemical Properties of Ipsapirone Derivatives Based on Chromatographic and Chemometric Approaches

Drug discovery is a challenging process, with many compounds failing to progress due to unmet pharmacokinetic criteria. Lipophilicity is an important physicochemical parameter that affects various pharmacokinetic processes, including absorption, metabolism, and excretion. This study evaluated the lipophilic properties of a library of ipsapirone derivatives that were previously synthesized to affect dopamine and serotonin receptors. Lipophilicity indices were determined using computational and chromatographic approaches. In addition, the affinity to human serum albumin (HSA) and phospholipids was assessed using biomimetic chromatography protocols. Quantitative Structure-Retention Relationship (QSRR) methodologies were used to determine the impact of theoretical descriptors on experimentally determined properties. A multiple linear regression (MLR) model was calculated to identify the most important features, and genetic algorithms (GAs) were used to assist in the selection of features. The resultant models showed commendable predictive accuracy, minimal error, and good concordance correlation coefficient values of 0.876, 0.149, and 0.930 for the validation group, respectively.

Modification of gradient HPLC method for determination of small molecules' affinity to human serum albumin under column safety conditions: Robustness and chemometrics study

In the early stages of drug discovery, beyond the biological activity screening, determining the physicochemical properties that affect the distribution of molecules in the human body is an essential step. Plasma protein binding (PPB) is one of the most important investigated endpoints. Nevertheless, the methodology for measuring %PPB is significantly less popular and standardized than other physicochemical properties, like lipophilicity. Here, we proposed how to modify protocols presented by Valko into column safety conditions and evaluated their robustness using fractional factorial design. For robustness testing, four factors were selected: column temperature, mobile phase flow rate, maximum isopropanol concentration in the mobile phase, and buffer pH. Elaborate methods have been applied for the analysis of HSA affinity for three groups of antibiotic-oriented substances that vary in chemical structure: fluoroquinolones, sulfonamides, and tetrazole derivatives. Furthermore, based on the reversed-phase chromatography the workflow of pilot studies was proposed to select molecules that have high affinity to HSA and can not be eluted from the HSA column using the concentration of organic modifier recommended by the column manufacturer.

DSC, TGA-FTIR and FTIR Assisted by Chemometric Factor Analysis and PXRD in Assessing the Incompatibility of the Antiviral Drug Arbidol Hydrochloride with Pharmaceutical Excipients

Arbidol hydrochloride is an antiviral product widely used in Russia and China for the treatment of, among other diseases, influenza. In recent years, it has turned out to be highly effective against COVID-19. However, there is little knowledge about its physicochemical properties and its behavior in the presence of various pharmaceutical excipients, which could be useful in the development of new preparations by increasing its solubility and bioavailability. For this reason, binary mixtures composed of arbidol hydrochloride and selected pharmaceutical excipients such as chitosan, polyvinylpyrrolione K-30 and magnesium stearate were prepared and subjected to differential scanning calorimetry (DSC), thermogravimetry combined with Fourier transform infrared spectrometry (TGA-FTIR) and Fourier transform infrared spectrometry (FTIR) analyses. In order to obtain clarity in the interpretation of the outcomes, chemometric calculations with factor analysis (FA) were used. Additionally, a powder X-ray diffraction (PXRD) and an intrinsic dissolution rate study were performed for arbidol hydrochloride itself and in the presence of excipients. As a result of the study, it was revealed that arbidol hydrochloride may undergo polymorphic transformations and be incompatible with chitosan and magnesium stearate. However, mixing arbidol hydrochloride with polyvinylpyrrolidone K-30 guarantees the obtaining of durable and safe pharmaceutical preparations.

Evaluation of the Effect of Antibacterial Peptides on Model Monolayers

The aim of the study was to assess the effect of the synthesized antibacterial peptides: P2 (WKWK)2-KWKWK-NH2, P4 (C12)2-KKKK-NH2, P5 (KWK)2-KWWW-NH2, and P6 (KK)2-KWWW-NH2 on the physicochemical properties of a model biological membrane made of azolectin or lecithin. The Langmuir Wilhelmy method was used for the experiments. Based on the compressibility factor, it was determined that the monolayers formed of azolectin and peptides in the aqueous subphase are in the condensed liquid phase. At the boundary between the condensed and expanded liquid phases, there was a monolayer made of lecithin and P4, P5 or P6 in the aqueous subphase. In turn, the film consisting of lecithin alone (37.7 mN/m) and lecithin and P2 (42.6 mN/m) in the water subphase was in the expanded liquid phase. All peptides change, to varying degrees, the organization and packing of molecules in the monolayer, both those made of azolectin and of lecithin. The test results can be used for further research to design a system with the expected properties for specific organisms.

Prediction of the chromatographic hydrophobicity index with immobilized artificial membrane chromatography using simple molecular descriptors and artificial neural networks

Screening of physicochemical properties should be considered one of the essential steps in the drug discovery pipeline. Among the available methods, biomimetic chromatography with an immobilized artificial membrane is a powerful tool for simulating interactions between a molecule and a biological membrane. This study developed a quantitative structure-retention relationships model that would predict the chromatographically determined affinity of xenobiotics to phospholipids, expressed as a chromatographic hydrophobicity index determined using immobilized artificial membrane chromatography. A heterogeneous set of 261 molecules, mostly showing pharmacological activity or toxicity, was analyzed chromatographically to realize this goal. The chromatographic analysis was performed using the fast gradient protocol proposed by Valko, where acetonitrile was applied as an organic modifier. Next, quantitative structure-retention relationships modeling was performed using multiple linear regression (MLR) methods and artificial neural networks (ANNs) coupled with genetic algorithm (GA)-inspired selection. Subsequently, the selection of the best ANN was supported by statistical parameters, the sum of ranking differences approach with the comparison of rank by random numbers and hierarchical cluster analysis.

Antimicrobial and Antioxidative Activity of Newly Synthesized Peptides Absorbed into Bacterial Cellulose Carrier against Acne vulgaris

The ongoing search for effective treatment of Acne vulgaris is concentrated, i.a., on natural peptides with antimicrobial properties. The aim of this work was the development of new amino acid derivatives with potential activity on dermal infections against selected microorganisms, including the facultative anaerobe C. acne. The peptides P1–P6 were synthesized via Fmoc solid phase peptide synthesis using Rink amide AM resin, analyzed by RP-HPLC-MS, FTIR, DPPH radical scavenging activity, and evaluated against C. acne and S. aureus, both deposited and non-deposited in BC. Peptides P1–P6 presented a lack of cytotoxicity, antimicrobial activity, or antioxidative properties correlated with selected structural properties. P2 and P4–P6 sorption in BC resulted in variable data, i.a., confirming the prospective topical application of these peptides in a BC carrier.

Application of Dominance-Based Rough Set Approach for Optimization of Pellets Tableting Process

Multiple-unit pellet systems (MUPS) offer many advantages over conventional solid dosage forms both for the manufacturers and patients. Coated pellets can be efficiently compressed into MUPS in classic tableting process and enable controlled release of active pharmaceutical ingredient (APIs). For patients MUPS are divisible without affecting drug release and convenient to swallow. However, maintaining API release profile during the compression process can be a challenge. The aim of this work was to explore and discover relationships between data describing: composition, properties, process parameters (condition attributes) and quality (decision attribute, expressed as similarity factor f₂) of MUPS containing pellets with verapamil hydrochloride as API, by applying a dominance-based rough ret approach (DRSA) mathematical data mining technique. DRSA generated decision rules representing cause–effect relationships between condition attributes and decision attribute. Similar API release profiles from pellets before and after tableting can be ensured by proper polymer coating (Eudragit^® NE, absence of ethyl cellulose), compression force higher than 6 kN, microcrystalline cellulose (Avicel^® 102) as excipient and tablet hardness ≥42.4 N. DRSA can be useful for analysis of complex technological data. Decision rules with high values of confirmation measures can help technologist in optimal formulation development.

Affinity of Antifungal Isoxazolo[3,4-b]pyridine-3(1H)-Ones to Phospholipids in Immobilized Artificial Membrane (IAM) Chromatography

Currently, rapid evaluation of the physicochemical parameters of drug candidates, such as lipophilicity, is in high demand owing to it enabling the approximation of the processes of absorption, distribution, metabolism, and elimination. Although the lipophilicity of drug candidates is determined using the shake flash method (n-octanol/water system) or reversed phase liquid chromatography (RP-LC), more biosimilar alternatives to classical lipophilicity measurement are currently available. One of the alternatives is immobilized artificial membrane (IAM) chromatography. The present study is a continuation of our research focused on physiochemical characterization of biologically active derivatives of isoxazolo[3,4-b]pyridine-3(1H)-ones. The main goal of this study was to assess the affinity of isoxazolones to phospholipids using IAM chromatography and compare it with the lipophilicity parameters established by reversed phase chromatography. Quantitative structure-retention relationship (QSRR) modeling of IAM retention using differential evolution coupled with partial least squares (DE-PLS) regression was performed. The results indicate that in the studied group of structurally related isoxazolone derivatives, discrepancies occur between the retention under IAM and RP-LC conditions. Although some correlation between these two chromatographic methods can be found, lipophilicity does not fully explain the affinities of the investigated molecules to phospholipids. QSRR analysis also shows common factors that contribute to retention under IAM and RP-LC conditions. In this context, the significant influences of WHIM and GETAWAY descriptors in all the obtained models should be highlighted.

A Novel Approach to Optimize Hot Melt Impregnation in Terms of Amorphization Efficiency

In this study, an innovative methodology to optimize amorphization during the hot melt impregnation (HMI) process was proposed. The novelty of this report revolves around the use of thermal analysis in combination with design of experiments (DoEs) to reduce residual crystallinity during the HMI process. As a model formulation, a mixture of ibuprofen (IBU) and Neusilin was used. The main aim of the study was to identify the critical process parameters of HMI and determine their optimal values to assure a robust impregnation process and possibly the highest possible amorphization rate of IBU. In order to realize this, a DoE approach was proposed based on a face-centered composite design involving three factors. The IBU/Neusilin ratio, the feeding rate, and the screw speed were considered as variables, while the residual crystallinity level of IBU, determined using differential scanning calorimetry (DSC), was measured as the response. Additionally, the stability of IBU under HMI was analyzed using high-performance liquid chromatography to estimate the extent of potential degradation. In order to verify the correctness of the DoE model, tested extrudates were manufactured by HMI and the obtained extrudates were thoroughly examined using scanning electron micrography, X-ray powder diffraction, and DSC.

Are the short cationic lipopeptides bacterial membrane disruptors? Structure-Activity Relationship and molecular dynamic evaluation

Short cationic lipopeptides are amphiphilic molecules that exhibit antimicrobial activity mainly against Gram-positives. These compounds bind to bacterial membranes and disrupt their integrity. Here we examine the structure-activity relation (SAR) of lysine-based lipopeptides, with a prospect to rationally design more active compounds. The presented study aims to explain how antimicrobial activity of lipopeptides is affected by the charge of lipopeptide headgroup and the length of lipopeptide acyl chain. The obtained SAR models suggest that the lipophilicity of short synthetic cationic lipopeptides is the major factor that determines their antimicrobial activities. In order to link the differences in antimicrobial activity to the mechanism of action of lipopeptides containing one and two hydrophobic chains, we additionally performed molecular dynamic (MD) simulations. By using combined coarse-grained and all-atom simulations we also show that these compounds neither affect the organization of the membrane lipids nor aggregate to form separate phases. These results, along with the onset of antimicrobial activity of lipopeptides well below the critical micelle concentration (CMC), indicate that lipopeptides do not act in a simple detergent-like manner.

Characterization of antimicrobial and hemolytic properties of short synthetic cationic lipopeptides based on QSAR/QSTR approach

In this study, we investigated the influence of molecular descriptors of cationic lipopeptides on their antimicrobial activity and hemolytic properties. The quantitative structure-activity relationship and quantitative structure-property relationship models were constructed. The antimicrobial, hemolytic and retention data were used as dependent variable and structural parameters as the independent ones. The obtained results suggest that the chromatographic indexes can be employed for prediction of antibacterial activity and that lipopeptides present nonspecific interaction between erythrocytes and bacterial membranes.

Formulation and In Vitro Characterization of Bioactive Mesoporous Silica with Doxorubicin and Metronidazole Intended for Bone Treatment and Regeneration

The purpose of this study was to evaluate the surface mineralization activity and in vitro drug behavior potential of two forms of mesoporous silica: powder and granulate. Ordered mesoporous SiO₂ powder was synthesized by surfactant-assisted sol-gel process using tetraethoxysilane as a silica precursor and hexadecyltrimethylammonium bromide as the structure-directing agent. The granulate was prepared using silica powder and ethyl cellulose as a binding agent. Metronidazole (MT)-an anti-inflammatory substance and doxorubicin hydrochloride (ChD)-an anti-cancer drug were chosen as drug models for delivery studies. The results of structural characteristic studies, utilizing transmission electron microscope (TEM) and scanning electron microscope (SEM) images, powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and nitrogen adsorption-desorption (BET) measurements, show that obtained materials have two-dimensional hexagonal p6mm symmetry, high specific surface area, narrow pore size, and a satisfactory mineralization behavior in the simulated body solution (SBF, pH = 7.4). The release rate of drugs depends upon the structural features of the drug molecules and the form of the carrier material. Of both the drugs analyzed, faster release was observed for small MT molecules characterized by weaker interactions with the carrier. In addition, the slower drug release was observed with granulate form due to increased diffusion barrier for drugs. Obtained results prove that the MT/ChD-loaded silica formulations could be attractive materials for filling bone defects and for local delivery systems.

A New Method To Identify Physically Stable Concentration of Amorphous Solid Dispersions (I): Case of Flutamide + Kollidon VA64

In this paper, a novel approach to determine stable concentration in API-polymer systems is presented. As a model, binary amorphous mixtures flutamide (FL) drug with a copolymer Kollidon VA64 (PVP/VA) have been used. It is worthwhile to note that finding an effective method to achieve this goal is a matter of great importance because physical stability of the amorphous pharmaceuticals is the key issue that is investigated worldwide. Due to the fact that molecular dynamics was found to be the crucial factor affecting physical stability of disordered pharmaceuticals, we examined it for both neat FL and its PVP/VA mixtures by means of broadband dielectric spectroscopy (BDS). Thorough investigation of the impact of polymeric additive on the molecular mobility of disordered FL reveals unusual, previously unreported behavior. Namely, simultaneously with the beginning of the recrystallization process, we observe some transformation from unstable supersaturated concentration of investigated mixture to the different, unknown concentration of FL-PVP/VA. Observed, during BDS experiment, transformation enables us to determine the limiting, highly physically stable concentration of FL in PVP/VA polymer (saturated solution), which is equivalent to FL + 41% wt. of PVP/VA. The described high physical stability of this unveiled system has been confirmed by means of long-term XRD measurements. According to our knowledge, this is the first time when such a behavior has been observed by means of BDS.

Toward a Better Understanding of the Physical Stability of Amorphous Anti-Inflammatory Agents: The Roles of Molecular Mobility and Molecular Interaction Patterns

The aim of this article is to examine the crystallization tendencies of three chemically related amorphous anti-inflammatory agents, etoricoxib, celecoxib, and rofecoxib. Since the molecular mobility is considered as one of the factors affecting the crystallization behavior of a given material, broadband dielectric spectroscopy was used to gain insight into the molecular dynamics of the selected active pharmaceutical ingredients. Interestingly, our experiments did not reveal any significant differences in their relaxation behavior either in the supercooled liquid or in the glassy state. Hence, as a possible explanation for the enhanced physical stability of etoricoxib, its ability to undergo a tautomerization reaction was recognized. The occurrence of intramolecular proton transfer in the disordered etoricoxib was proven experimentally by time-dependent dielectric and infrared (IR) measurements. Additionally, IR spectroscopy combined with density functional theory calculations pointed out that in the etoricoxib drug, being in fact a binary mixture of tautomers, the individual isomers may interact with each other through a hydrogen bonding network. A possible explanation of this issue was achieved by performing dielectric experiments at elevated pressure. Since compression results in etoricoxib recrystallization, the possible influence of pressure on the observed stabilization effect is also carefully discussed.

Physicochemical properties of tadalafil solid dispersions - Impact of polymer on the apparent solubility and dissolution rate of tadalafil

To improve solubility of tadalafil (Td), a poorly soluble drug substance (3μg/ml) belonging to the II class of the Biopharmaceutical Classification System, its six different solid dispersions (1:1, w/w) in the following polymers: HPMC, MC, PVP, PVP-VA, Kollicoat IR and Soluplus were successfully produced by freeze-drying. Scanning electron microscopy showed a morphological structure of solid dispersions typical of lyophilisates. Apparent solubility and intrinsic dissolution rate studies revealed the greatest, a 16-fold, increase in drug solubility (50μg/ml) and a significant, 20-fold, dissolution rate enhancement for the Td/PVP-VA solid dispersion in comparison with crystalline Td. However, the longest duration of the supersaturation state in water (27μg/ml) over 24h was observed for the Td solid dispersion in HPMC. The improved dissolution of Td from Td/PVP-VA was confirmed in the standard dissolution test of capsules filled with solid dispersions. Powder X-ray diffraction and thermal analysis showed the amorphous nature of these binary systems and indicated the existence of dispersion at the molecular level and its supersaturated character, respectively. Nevertheless, as evidenced by film casting, the greatest ability to dissolve Td in polymer was determined for PVP-VA. The crystallization tendency of Td dispersed in Kollicoat IR could be explained by the low Tg (113°C) of the solid dispersion and the highest difference in Hansen solubility parameters (6.8MPa(0.5)) between Td and the polymer, although this relationship was not satisfied for the partially crystalline dispersion in PVP. Similarly, no correlation was found between the strength of hydrogen bonds investigated using infrared spectroscopy and the physical stability of solid dispersions or the level of supersaturation in aqueous solution.

EVALUATION OF CASES WITH THE USAGE OF COMMERCIALLY AVAILABLE TABLETS IN THE PEDIATRIC FORMULA

Lack of availability, of either the medicinal product intended to be used for children, or such in a dose which is fitting for the individual child's needs, results in physicians administering medicines meant for the adult. The target of the thesis was to evaluate the cases with the usage of commercially avaible conventional tablet-formulated medicinal products intended for the adult in the pediatric formula. The subjects of the evaluation were the form of the pediatric drug, prepared from commercially available tablets and capsules, as well as the legitimacy of their usage in the treatment of the pediatric population. One hundred and fifty-four prescriptions filled in community pharmacies of Warminsko-Mazurskie Voivodeship in 2011 were chosen. A total of 5805 divided powders in starch capsules were prepared. The prescribing practice included 6 groups of manufactured medicinal products in the form of conventional tablets, containing as follows: anti-hypertensive medicines (ACE inhibitors--enalapril, captopril, ramipril, loop diuretics--furosemide, potassium sparing diuretics--spironolactone, β-adrenolytics--propranolol, α- and β-adrenolytics--carvedilol), medicines for heart failure (foxglove glycosides--digoxin, methyldigoxin), anti-clotting medicines (acetylsalicylic acid), peristalsis stimulating agents (metoclopramide), antibacterial medicines (furagin), and dopaminergic (carbidopa-levodopa). The only compounded forms ordered by the physicians were divided powders for an internal use. Starch capsules for powder preparation provided the only 'package' for the dose of the compounded powder, which after pouring, solving or suspending in water was administered to children. Such a shift of the form, between an oral tablet and divided powder for an internal use, did not cause a change in the method of administration. The information on indications and the way of dosage for children, inserted in the Summary of Product Characteristics, enables the administration which follows the registered indications, despite the shortage of an appropriate dose in the pharmaceutical market. In contrast, an absence of the information regarding the indications and a dosage for children in the Summary of Product Characteristic, results in an off-label administration, in case of a child.

Biopharmaceutical evaluation of new slow release tablets obtained by hot tableting of coated pellets with tramadol hydrochloride

This study was aimed at a biopharmaceutical evaluation of a new oral dosage form of tramadol hydrochloride (TH)--slow release tablets obtained by hot tableting of coated pellets, 100 mg (TP), compared to the conventional slow release tablets, Tramal Retard, 100 mg (TR). Both TP and TR formulations showed a similar release profile of TH (f2 was 71) in in vitro release studies. The in vivo study was a two-treatment, two-period, two-sequence, single-oral dose 100 mg, crossover design using rabbit model with the phases separated by a washout period of 14 days. It was shown that the amount of TH absorbed into the systemic circulation is similar for TP and TR (the 90% confidence intervals for the AUC(0-1), AUC(0-infinity) and ratios were 85-122 and 92-107%, respectively). However, after administration of slow release tablets obtained by hot tableting of coated pellets, a prolonged absorption and elimination processes and a smoother and more extended plasma profile of TH were observed. It can be assumed that the use of a new oral dosage form of TH in patients affects the extension of analgesia after single administration of the drug, with its gradual absorption into the systemic circulation.

In vitro - in vivo evaluation of a new oral dosage form of tramadol hydrochloride--controlled-release capsules filled with coated pellets

The aim of this study was an in vitro - in vivo evaluation of a new oral dosage form of tramadol hydrochloride (TH), controlled-release capsules filled with coated pellets, 100 mg (TC), compared to the sustained release tablets, Tramal Retard, 100 mg (TR). In vitro release study of both formulations showed a similar release profile of TH over 8 h (f2 was 52). In vivo study (single oral, 100 mg dose administration in 8 rabbits) showed that the amount of TH absorbed into the systemic circulation after TC and TR administration was also similar (90% CI for AUC(0-t) and AUC(0-infinity) were 90-124% and 97-109%, respectively). However, a comparison of AUC(0-t) of pharmacokinetics of TC and TR indicates significantly prolonged absorption and elimination processes of TH when the drug is given in controlled-release capsules filled with coated pellets. It was manifested by longer: mean absorption time (p = 0.0016), mean residence time (p = 0.0268), absorption half-life (p = 0.0016), elimination half-life (p = 0.0493) and lower: absorption rate constant (p = 0.0016), elimination rate constant (p = 0.0148) and total body clearance Cl/F (p = 0.0076). It may be concluded that the new TH formulation could be expected to have a more prolonged analgesic activity than commercial sustained release tablets.

Biological and surface-active properties of double-chain cationic amino acid-based surfactants

Cationic amino acid-based surfactants were synthesized via solid phase peptide synthesis and terminal acylation of their α and ε positions with saturated fatty acids. Five new lipopeptides, N-α-acyl-N-ε-acyl lysine analogues, were obtained. Minimum inhibitory concentration and minimum bactericidal (fungicidal) concentration were determined on reference strains of bacteria and fungi to evaluate the antimicrobial activity of the lipopeptides. Toxicity to eukaryotic cells was examined via determination of the haemolytic activities. The surface-active properties of these compounds were evaluated by measuring the surface tension and formation of micelles as a function of concentration in aqueous solution. The cationic surfactants demonstrated diverse antibacterial activities dependent on the length of the fatty acid chain. Gram-negative bacteria and fungi showed a higher resistance than Gram-positive bacterial strains. It was found that the haemolytic activities were also chain length-dependent values. The surface-active properties showed a linear correlation between the alkyl chain length and the critical micelle concentration.

Pharmacokinetics and pharmacodynamics of gliclazide from immediate and modified release formulation tablets in rats

The objective of the study was to compare pharmacokinetic and pharmacodynamic parameters of gliclazide after administration of immediate (IR) and modified release (MR) tablets. The experiment included rats with both normoglycemia and streptozocin (STZ)-induced hyperglycemia. Several MR formulations were designed and in-vitro drug release profile was assessed by a dissolution test. For the further in-vivo study the most suitable formulation was chosen. For pharmacokinetic analysis concentrations of gliclazide in plasma were determined by a validated high performance liquid chromatography (HPLC) method with UV detection. Pharmacodynamic efficacy of the drug was evaluated by measuring blood glucose concentrations. Gliclazide bioavailability was totally different for two formulations in both healthy and diabetic rats based on area under the curve (AUC), time to peak concentration (tmax) and peak concentration (Cmax). Reduction of blood glucose level was significantly higher after the administration of IR than MR formulation. The highest pharmacodynamic efficacy of gliclazide was observed in the normal animals group after administration of the IR tablets, while hypoglycemic effect of the drug was diminished in animals with induced diabetes. Our study suggested that results of reduction in blood glucose level for STZ-induced groups were not comparable with pharmacodynamic effect for normal group. It may be assumed that a decrease in glycemia in healthy subjects might not be a suitable factor for characterizing anti-diabetic drugs.

Molecular dynamics studies on the water mixtures of pharmaceutically important ionic liquid lidocaine HCl

In this paper the molecular dynamics of a common local-anesthetic drug, lidocaine hydrochloride (LD-HCl), and its water mixtures were investigated. By means of broadband dielectric spectroscopy and calorimetric measurements it was shown that even a small addition of water causes a significant effect on the relaxation dynamics of analyzed protic ionic liquid. Apart from the two well-resolved relaxations (σ- and γ-processes) and the β-mode, identified as the JG-process, observed for anhydrous LD-HCl, a new relaxation peak (υ) is visible in the dielectric spectra of aqueous mixtures of this drug. Additionally, the significant effect of the water on the glass transition temperature of LD-HCl was found. The sample characterized with mole fraction of water X(w) = 0.44 reveals the glass transition temperature T(g), 42 K lower than that of anhydrous material (307 K). Finally, it was shown that by amorphization of the hydrochloride salt of lidocaine it is possible to obtain its room temperature ionic liquid form.

Bioactive silica-based drug delivery systems containing doxorubicin hydrochloride: in vitro studies

This study reports the applicability of sol-gel derived silica and silica-polydimethylsiloxane (silica-PDMS) composites as a potential bioactive implantable drug delivery system for doxorubicin hydrochloride (DOX). These composites also contain calcium chloride (CaCl(2)) and triethylphosphate as precursors of Ca(2+) and (PO(4))(3-) ions. These composites were immersed for 20 days in a simulated body fluid (SBF) at 37°C to study the release rate of the DOX, dissolution of the silica and the formation of hydroxyapatite on the composites' surface. The results show that the release rate of the DOX can be effectively tailored by either the addition of a polydimethylsiloxane (PDMS), or by varying the amount of CaCl(2), where the elution rate of DOX increases with increasing amount of the CaCl(2) precursor. Importantly, irrespective of the amount of CaCl(2), no burst release of DOX has been observed in any of the silica-PDMS system investigated. On the other hand, a slow release of DOX has been observed with a trend that followed a zero (0)-order kinetics for a total of 20 days of elusion. The dissolution of silica in SBF was ca. two-times faster than that of silica-PDMS, with the former reaching an average saturation level of 80 μg/mL whilst the latter reached 46 μg/mL within 20 days. Both the silica and the silica-PDMS composites show bioactivity i.e. they absorb calcium phosphate from SBF. Within 10 days, a ten-fold increase in the concentration of calcium phosphate deposit has been observed on the silica-PDMS relative to the silica. The constant rates of DOX release observed for the silica-PDMS composites indicate that the calcium phosphate deposit do not obstruct controlled release of the drug.

Influence of surfactants on the release behaviour and structural properties of sol-gel derived silica xerogels embedded with metronidazole

The aim of this study was to obtain stable and controlled release silica xerogels containing metronidazole (MT) prepared with surfactants with different charges: cetyltrimethylammonium bromide (CTAB), sodium dodecyl sulphate (SDS) and hydroxypropyl cellulose (HPC), which could be the promising carrier materials used as the implantable drug delivery systems. The xerogels were prepared by the sol-gel method. The influence of various formulation precursors on porosity parameters and drug release were investigated. Addition of surfactants showed a promising result in controlling the MT release. Dissolution study revealed increased release of MT from silica modified SDS and CTAB, whereas the release of MT from silica modified HPC considerably decreased, in comparison with unmodified silica. The addition of surfactants showed slight changes in porosity parameters. All xerogels are characterized by a highly developed surface area (701-642 m(2) g(-1)) and mesoporous structure. The correlation between pore size obtained matrices and release rate of drug was also observed. Based on the presented results of this study, it may be stated that applied xerogel matrices: pure silica and surfactants-modified silica could be promising candidates for the formulation in local delivery systems.

The sol-gel prepared SiO2-CaO-P2O5 composites doped with Metronidazole for application in local delivery systems

The aim of this study was to evaluate the physical properties, chemical structure and bioactivity of sol-gel processed oxide (SiO(2)-CaO-P(2)O(5)) composites used as controlled release materials for Metronidazole-drug applied in periodontal disease treatment. The obtained composite materials were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), the Brunauer-Emmet-Teller (BET) technique and further monitoring in the ultraviolet and visible light regions (UV-Vis) of the in vitro release of the drug over time. Using tetramethoxysilane (TMOS) as a precursor of silica matrix and calcium nitrate tetrahydrate (Ca(NO(3))(2) 4H(2)O), triethyl phosphite (P(OC(2)H(5))(3)) as precursors of CaO and P(2)O(5) respectively, xerogels with different morphology and physical properties were obtained. The applied modifications improved also the bioactivity and changed the profile of the drug release. Based on the presented results of this study, it may be concluded that applied xerogel matrices could be promising candidates for the formulation in local delivery systems.

Dielectric relaxation study on tramadol monohydrate and its hydrochloride salt

Dielectric relaxation measurements as well as differential scanning calorimetry and X-ray diffraction investigations were performed on tramadol monohydrate and its hydrochloride salt. Examined samples do not crystallize during cooling and in consequence they reach the glassy state. In the case of the hydrochloride tramadol we are able to monitor alpha-relaxation process despite large contribution of dc conductivity to the loss spectra. It is the first such study on the salt of the drug. Up to now the dielectric spectroscopy has been regarded as useless in measuring such kind of API (active pharmaceutical ingredient). In this paper we also made some suggestions about the nature of the secondary relaxations in the amorphous tramadol monohydrate and its salt. The knowledge about the molecular mechanisms, which govern the observed secondary relaxations seems to be the key in predicting the stability of the amorphous form of the examined API. Finally additional dissolving measurements on the amorphous and crystal tramadol hydrochloride were performed. As a result we understood that dissolution properties of the amorphous form of the considered drug are comparable to those of crystalline one. However, we have found out that amorphous tramadol hydrochloride has greater ability to form tablets than its crystalline equivalent. This finding shows that amorphous drugs can be alternative even for the freely solved pharmaceuticals such as tramadol hydrochloride, because the former one has better ability to form tablets. It implies that during tabletting of the amorphous drugs there is no need to use any excipients and chemicals improving compaction properties of the API.

Study of the amorphous glibenclamide drug: analysis of the molecular dynamics of quenched and cryomilled material

Glibenclamide (GCM) is an oral hypoglycemic agent of the sulfonylurea group used in the treatment of non-insulin-dependent diabetes. Crystalline GCM is characterized by low bioavailability, which is attributed to its poor dissolution properties. It prompted us to prepare this drug in its amorphous form as a means to enhance its dissolution characteristics. Two different methods were used to convert crystalline GCM into the glassy form: quench-cooling of the melt and cryogenic milling. To monitor solid-state properties of the amorphous samples, X-ray powder diffraction (XRD), infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), ultraperformance liquid chromatography (UPLC) and spectroscopy, and broadband dielectric spectroscopy (BDS) were applied. The results of UPLC separations along with associated infrared and NMR measurements unambiguously showed that the thermal degradation of the quenched GCM, as suggested in literature reports, does not occur. A similar analysis performed on the cryomilled material also did not indicate any chemical decomposition. On the other hand, both methods confirmed that the conversion to the amorphous form is connected with the amide-imidic acid tautomerism of the examined drug. Moreover it was shown that this transformation occurs regardless of the manner of amorphization. Finally, dielectric spectroscopy was employed to study the molecular dynamics of vitrified GCM. The analysis of the ε''(f) in terms of the KWW function from the dielectric measurements revealed the existence of an "excess wing" attributed to the true Johari-Goldstein process based on Ngai's coupling model. The dielectric properties of GCM obtained in the amorphous form both by rapid cooling of the melt and the cryogenic grinding of crystalline sample were also compared.

Hot tabletting of slow-release tramadol hydrochloride microcapsules with cores obtained via compaction

BACKGROUND

Coating, as a processing technique, applied to active pharmaceutical ingredient (API) crystals or particles (carriers) with an appropriate polymer allows to obtain a modified-release pharmaceutical dosage form. Such carriers can be the basic ingredient of a multi-unit dosage form. Additionally, coated API crystals (microcapsules) can provide an alternative to spherical granulate (pellets) as the main and most commonly used component of multi-unit dosage forms. Coating individual API crystals is a complicated process because of the crystals having insufficient size (below 100 microm), irregular shape, low mechanical durability and the fact that API crystals dissolve upon contact with the coating mixture, and other factors.

METHOD

Compaction process was used to eliminate these inconveniences allowing us to obtain tramadol hydrochloride (TH) microcapsule cores in the size range of 212-500 microm. The coating of the cores was successfully conducted using a fluidized-bed coating technique with four different polymers that allowed us to attain slow release of TH. Then, the microcapsules were subjected to a hot tabletting process conducted by applying a low compression force of about 1 kN at 56 degrees C. Semi-liquid granules containing melted PEG 3000 combined with TH microcapsules were compressed. A tablet matrix of good physical parameters was created when its temperature decreased to room temperature. In the proposed hot tabletting method, PEG 3000 included in the granulate provided the tableted microcapsules sufficient protection against rupture.

RESULTS

The compaction process allowed us to eliminate unwanted physical API properties, which could otherwise have an adverse effect on the fluidized-bed coating process. The microcapsule cores after compaction and coating using a fluidized-bed coating technique showed a TH-release profile similar to that of the compressed microcapsules after applying hot tabletting process.

CONCLUSIONS

Multi-unit dosage forms can be obtained in a relatively simple way by combining three processes: (i) obtaining TH microcapsule cores by compaction, (ii) coating, and (iii) hot tabletting.

Influence of the components of Kollicoat SR film on mechanical properties of floating pellets from the point of view of tableting

The influence of pellet core ingredients on pellet behaviour, e.g. during compression, is well known. In this study the influence of components of a Kollicoat SR polymer film on mechanical properties was investigated. The aim of this study was to evaluate the influence of polymer film components on the mechanical properties of the pellet as a whole, from the point of view of tableting. Tablets should disintegrate into undeformed pellets floating in this environment for 5-6 h, releasing the model drug--verapamil hydrochloride--if possible in a controlled way. The usefulness of texture analysis and work of compression measurement was also evaluated. Kollicoat SR in the form of a 30D aqueous dispersion was chosen as the main component of the polymer film. Polyvinyl pyrrolidone K-30 as a pore former, and propylene glycol, triethyl citrate and dibutyl sebacate plasticisers were selected as typical additives. The influence of different thickness of polymer film on behaviour during stress was also evaluated. After coating the cores with a 20 microm Kollicoat SR dispersion film, an increase in mechanical strength, in comparison to the pellet core, was observed (2.74 to 3.34 mJ). Addition of porophor increased the work of compression by 50% to 5.1 mJ. The investigation of the influence of plasticiser on film properties proved that the kind of plasticiser used in the polymer film had no effect on the mechanical properties of the film or pellets. Only in the case of the film with triethyl citrate was no distinct of the pellet core found. Pellets coated both with films with triethyl citrate and with dibutyl sebacate, in contrast to pellets with a film coating with propylene glycol, showed a significant decrease of the dissolution rate of verapamil hydrochloride (20, 10 and 40% at 6 hours, respectively). It is possible to compress pellets with a 50 microm polymer film without affecting the dissolution rate, as was confirmed during release studies. When using Kollicoat SR the most appropriate plasticizer seems to be triethyl citrate, and in this case a change of behavior during compression analysis by texture analyzer was observed. But so relationship was found between the type of plasticizer and the work needed to obtain a given deformation.

Fast disintegrating tablets containing Rhodiola rosea L. extract

Tablets with 250 mg of Rhodiola rosea L. extract disintegrating in less than 10 min were developed. The influence of the extract content and type of fillers and disintegrants on disintegration time and tablet hardness was evaluated. Type of the filler and the extract/filler ratio but not the type of disintegrant determined fast disintegration of the tablets. It was demonstrated that the extract:filler ratio lower than 1:1.5 enables preparation of tablets with the required disintegration time. The tablets containing microcrystalline cellulose as a filler, povidone as a binder and crospovidone as a disintegrant were stable during 6 months storage at 25 degrees C/60% RH, however, due to the decrease of hardness they did not pass the stability test at 40 degrees C/75% RH.

Influence of the type of cellulose on properties of multi-unit target releasing in stomach dosage form with verapamil hydrochloride

Microcrystalline cellulose (MCC) and powdered cellulose (PC) are commonly used excipients for solid dosage forms e.g., pellets. The aim of this study was to compare the utility of the MCC and PC in the floating pellet cores comprising verapamil hydrochloride (VH) manufactured by extrusion and spheronization and influence on their physical properties like swelling, compressibility and VH release. It was found by scanning electron microscopy (SEM) investigation that porosity of surface of the pellets' cores increased with an increase of PC amount in composition. Differential scanning calorimetry (DSC) analysis indicated the lack of physicochemical interaction between PC and MCC either with VH or with any excipients in the pellet core. Formulation having the highest PC participation were characterized by the highest friability and compressibility and addition of MCC corresponded with a decrease of friability and compressibility. The results on pellets friability were not reflected by the results on the hardness test. It means that the PC contents growth contributes to the hardness growth. The swelling forces of physical mixture of powders containing PC and MCC was different and increased with increasing amount of PC in pellet's core. Pellets' cores were coated with Eudragit NE dispersion. It was found that VH release rate from coated pellets with higher amount of PC was considerably slower in comparison to the pellets containing highest MCC participation.

Influence of acrylic esters and methacyrlic esters on flotation of pellets and release rate of verapamil hydrochloride

Eudragit RL (ERL) and Eudragit RS (ERS) are biocompatible cationic copolymers, pH-independent and insoluble in aqueous environment. In this study drug delivery system consisting of a capsule filled with floating pellets with verapamil hydrochloride (VH) is proposed. The release of VH in the stomach results in better solubility in an acid gastric environment in vivo and may result in greater amount of the VH absorbed and its higher concentration in plasma. The scope of this study was to investigate the influence of ERL and ERS ratio on VH release in 0,1 M HCl from floating coating pellets. The stability of this film was also investigated. The ERL film is much more permeable than ERS, and an increase of ERL film thickness did not retard the release rate. The combination of ERL and ERS are forms of the sustained release film. It was a necessary to add the uncoated pellets, which constituted the initial dose. The start of flotation depends on permeability of polymeric film, and decreases with addition of ERS. There is no change in the start flotation time after 12 months under room condition (25 degrees C/60% RH). The drug delivery from uncoated pellets and pellets coated with ERL/ERS is stable after 12 months under room condition (25 degrees C/60% RH).

Compressibility of floating pellets with verapamil hydrochloride coated with dispersion Kollicoat SR 30 D

The purpose of this study was to work out a method of compression of floating pellets with verapamil hydrochloride (VH) in a dose of 40 mg. It was assumed that this form should reside in the stomach floating for several hours and gradually release the drug in a controlled way. Compression of pellets into tablets, being a modern technological process, is much more perfect than enclosing them in a hard gelatin capsule. Kollicoat SR 30 D was selected for coating. In experiments three plasticizers were examined-propylene glycol, triethyl citrate and dibuthyl sebecate (all at concentration of 10%). It was found that VH release from pellets coated by the films of the same thickness (70 microm), however, containing plasticizers is considerably different. Pellets were prepared by wet granulation of powder mixture, spheronization of the granulated mass and coating of the cores with a sustained release film. Two kinds of cellulose, microcrystalline and powdered, and sodium hydrocarbonate were the main components of pellet core. Proper pellet coating film thickness, ensuring obtaining desirable VH release profile and flotation effect, was defined. X compositions of tablets with pellets were examined in order to obtain formulation, from which VH release would mostly approximate pellets before compressing. The best formulation was evaluated taking into account the effect of compression force an tablet hardness and friability, and pellet agglomeration and flotation. Tablet cross-section photographs were taken confirming necessary coating film thickness preventing their deformation caused by compressing into tablets.

Outcome and prognostic factors in advanced Hodgkin's disease treated with high-dose chemotherapy and autologous stem cell transplantation: a study of 341 patients

BACKGROUND

The reported probability of survival of patients with Hodgkin's disease (HD) following high-dose chemotherapy with autologous stem cell transplantation (HDC/ASCT) is 35-65% at 5 years. The Polish Lymphoma Research Group investigated retrospectively prognostic factors for overall survival (OS) and event-free survival (EFS), and the risk of secondary malignancies in a large series of patients who underwent HDC/ASCT.

PATIENTS AND METHODS

The data of 341 consecutive patients treated in 10 centers from 1990 to 2002 were collected and analyzed.

RESULTS

The actuarial 5-year OS and EFS were 64% [95% confidence interval (CI) 57% to 71%] and 45% (95% CI 39% to 51%), respectively. In the multivariate model, unfavorable prognostic factors for EFS were less than partial response at the time of ASCT [relative risk (RR), 2.92 (95% CI 1.68-5.08); P<0.001] and three or more previous chemotherapy lines (RR, 2.16; 95% CI 1.42-3.30; P<0.001). These two factors were also associated with unfavorable OS (RR, 3.32; 95% CI 1.90-5.79; P<0.001 and RR, 2.34, 95% CI 1.51-3.64; P<0.001). Five-year cumulative risk of secondary malignancy was 8.4% (95% CI 2% to 13%) and the only identified risk factor was splenectomy (P=0.02).

CONCLUSIONS

HDC/ASCT should be considered early in the course of disease for patients with a response after standard therapy.

Preparation of floating pellets with verapamil hydrochloride

The aim of this paper is to prepare a floating drug formulation in a gelatin capsule filled with tens of pellets with verapamil hydrochloride (VH) in a dose of 40 mg. The better solubility of VH in an acidic environment of the stomach may result in a greater amount of the drug absorbed. Pellets were prepared by wet granulation of a powder mixture, spheronization of the granulated mass and coating of the cores with aqueous dispersions of polymethylmethacrylate. Sodium hydrocarbonate contained in pellet cores ensures the flotation effect. Proper rate of VH release from pellets was obtained by a coating film of 25-105 microm thickness. Pellets of 1.25-1.6 mm size with a film of 75-85 microm thickness of considerably constant rate released the whole dose of VH in 6 h. During that time the pellets floated on the surface of the receptor solution.

The value of ultrasonography in preoperative assessment of selected prognostic factors in endometrial cancer

OBJECTIVE

To determine the efficiency of transabdominal and transvaginal ultrasonography (TAS and TVS) in the assessment of myometrial invasion, cervical involvement, pelvic lymph nodes, adnexal and omental metastases (preoperative staging) of endometrial cancer.

METHODS

Transabdominal and transvaginal 2D, ultrasound were performed on 90 women to classify myometrial invasion, cervical involvement, pelvic lymph nodes and adnexal metastases in endometrial cancer. According to this 13 type E (invasion involving the endometrium), 41 type S (superficial, of less than 50% of myometrial infiltration), 36 type D (deep infiltration) and 22 cervical involvement were identified. There were 15 G1, 60 G2 and 15 G3 cases. Adnexal, omental and lymph-node metastases were found in 11, two and 15 cases, respectively. Endometrial cancer was diagnosed on the basis of dilatation and curettage. The degree of invasion was evaluated preoperatively. Ultrasonographic findings were compared to surgical staging and histopathology of the surgical specimen.

RESULTS

The median age of the 90 women was 63.3 +/- 12.3 years (range 32 to 86 years). The median thickness of malignant endometrium was 19.5 +/- 9.6 (range 7 to 54 mm). In type E the median thickness was 11.76 +/- 4.2, in type S 17.3 +/- 7.6, in type D 24.8 +/- 9.8 and in cases with cervical involvement 23.2 +/- 11 mm. Myometrial invasion evaluated by TVS was accurate in 76 of 90 cases (accuracy 84.4%). In type E sensitivity was 92.3%, specificity 87.0%, positive and negative predictive value, respectively, 63.1% and 98.6%. In type S these values were respectively: 78.0%, 93.9%, 91.4%, 80.0% and in type D--88.9%, 92.6%, 88.9% and 100.0%. Tumor extension to the cervix was properly assessed in 19 of 22 women in which it was present (sensitivity 86.4%, specificity 85.3%, positive predictive value 85.5%, negative predictive value 95.1%). Adnexal metastasis was correctly diagnosed in 8 of 11 cases in which it was present (sensitivity 72.7%, specificity 97.5%, positive predictive value 80%, negative predictive value 96.3%), and lymph-node metastasis in only 5 of 15 cases (sensitivity 33.3%, specificity 100%, positive predictive value 100%, negative predictive value 88.2%).

CONCLUSION

These results suggest that 2D TAS and TVS evaluation of endometrial cancer are reliable methods for preoperative assessment of selected prognostic factors, e.g. myometrial invasion, cervical involvement and adnexal metastases. However in assessing lymph-node metastases, TVS with its low sensitivity, did not provide additional information. Preoperative ultrasound examination should be speculated as an important tool in the establishment of different surgical choices which can be made after a correct pretreatment prognosis.

The effectiveness of hysteroscopic polypectomy in cases of female infertility

The authors, based on their own material, evaluated the value of hysteroscopic treatment of endometrial polyps in a group of infertile women. Polypectomy was performed in 25 patients using either endoscopic microscissors or electric loop. Follow-up hysteroscopy was performed after two months as an integral part of the treatment. All the patients were observed for 12 months. The primary intrauterine investigation was complete in all patients without regard to kind of instrument which was confirmed by second-look hysteroscopy. About 80% of the patients who underwent surgery conceived. Restoration of reproductive ability did not depend on the size of the removed lesion.

Hysteroscopy in cases of cervical polyps

To assess the usefulness of hysteroscopy in cases of cervical polyps, we studied 78 patients with a lesion found during a routine gynecological examination. All women were referred for diagnostic hysteroscopy followed by endoscopic polypectomy. In 83.3% of the cases intrauterine investigation confirmed primary diagnosis - a polyp peduncle in the cervical canal. Sixty-five of those lesions were the only pathologic condition, and six (7.7%) were associated with an endometrial polyp. In the remaining 16.7% of examined patients, primary polyps identified as cervical polyps appeared to be endometrial. All women admitted to the study were successfully treated by hysteroscopy. Our results suggest that endoscopic evaluation of the uterine cavity in women with cervical polyps can clarify the initial diagnosis. Hysteroscopy allows not only a precise visualisation of the polyp peduncle but also gives the possibility to identify and treat concurrent asymptomatic intrauterine pathological conditions.

The importance of fine needle aspiration biopsy and sonographic evaluation of parametria in cervical cancer

OBJECTIVE

The aim of study was to estimate of the value of fine needle aspiration biopsy (FNAB) and transvaginal ultrasonography (TVS) in the preoperative assessment of the parametria in cervical cancer. We compared parametrial infiltration before and postoperatively by histopathology to verified and confirmed staging of disease. Correct staging qualification, especially evaluation of the parametrium, is very useful in choosing an adequate method of treatment, and thereby in patient survival.

MATERIAL AND METHOD

52 women (median age 56 years, range 33-85) with cervical cancer in Stage Ib and 49 (median age 51, range 36-71) in Stage II and III, were included in the study. Assessment of parametrial invasion before treatment was performed by fine needle aspiration biopsy (FNAB) with endovaginal ultrasound assistance. The sonographic evaluation of parametria was performed by Siemens Sonoline Versa Pro with a transvaginal 7 MHz mechanical transducer with a biopsy guide and 21-gauge needle. The probe was covered with a disposable latex sheath filled with ultrasound gel. The aspirated material was placed on a glass slide, fixed in 95% alcohol and submitted to cytologic evaluation. All of the patients with cervical cancer in Stage Ib underwent a Wertheim-Meigs hysterectomy. The preoperative findings were compared with data obtained by histopathology findings. Moreover, in the whole group of 101 patients a comparison of FNAB and sonography was performed. The sensitivity, specificity and diagnostic accuracy of this method were evaluated.

RESULTS

Parametrial involvement assessed postoperatively by histopathology, in clinical Stage Ib cervical cancer was found in eight of 52 cases (15.4%). FNAB of parametrial involvement in the operated group was accurate in 14 of 18 (accuracy--83%, sensitivity--78%, specificity--84%, PPV--50%, NPV--95%). Sonographic assessment of parametrial involvement was correct in 12 of 18 cases (accuracy--58%, sensitivity--67%, specificity--56%, PPV--24%, NPV--89%). In the whole group of patients (operated and non-operated), sonographic evaluation of parametria verified by FNAB was correct in 104 of 202 cases (accuracy--78%, sensitivity--71%, specificity--86%, PPV--84%, NPV--74%).

CONCLUSIONS

FNAB and TVS assessment of the parametria are very useful methods in confirmation of neoplastic infiltration. Correct preoperative diagnosis may improve staging, treatment and indirectly, survival of patients with cervical cancer.

High-dose chemotherapy with autologous stem cell transplantation is an effective treatment of primary refractory Hodgkin's disease. Retrospective study of the Polish Lymphoma Research Group

We analysed the treatment outcome of primary refractory HD patients managed with high-dose chemotherapy and haematopoietic cell transplantation. Data of 65 adult patients who underwent HDC/ASCT in nine Polish centres for primary resistant Hodgkin's disease between June 1991 and July 2000 were collected retrospectively. Response rate to HDC/ASC: CR, 54%; PR, 20%; less than PR, 15%; early deaths, 11%. Actuarial 3-year OS and PFS were 55% and 36%, respectively. In multivariate analysis, lack of bulky lymph nodes and use of immunotherapy were favourable factors for both OS and PFS. IPF <3 at the time of transplantation was predictive for PFS. However, the prognostic impact of immunotherapy should be interpreted with caution since this group included more patients who achieved CR after HDC/ASCT. The results of HDC/ASCT are encouraging and confirm earlier findings. The role of immunotherapy should be further investigated in prospective trials.