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E Ballatori

Publications and source records attributed to E Ballatori.

At least 19 recordsLinked to original sources

Statistical considerations in the design, conduct and analyses of antiemetic clinical trials. An emerging consensus.

Various aspects of trial design and planning for clinical testing of antiemetic therapies administered to cancer patients are considered. It is generally felt that a randomized double-blind parallel-arm design is the best. Ways of achieving adequate power of such studies are discussed briefly, as is the need for previous identification of primary and secondary end-points. Finally, summary recommendations are given.

Antiemetics

The efficacy and cost-effectiveness of various antiemetic regimens.

Recently, the availability of 5-hydroxytryptamine-3 antagonists has provided better protection from chemotherapy-induced emesis. These drugs, in combination with dexamethasone, are more expensive but more cost-effective than the alternative antiemetic regimens in the prevention of acute emesis induced by high single dose and low and repeated doses of cisplatin and, probably, of acute emesis induced by moderately emetogenic chemotherapy. In the prevention of emesis induced by oral cyclophosphamide-methotrexate-fluorouracil and in the prevention of delayed emesis induced by cisplatin and moderately emetogenic chemotherapy, the most cost-effective choices are represented, respectively, by a combination of intravenous dexamethasone on day 1 and 8 plus 14-day oral metoclopramide (a combination of oral dexamethasone plus metoclopramide and oral dexamethasone alone). In all cases, the 5-hydroxytryptamine-3 antagonists should be used only in patients in whom the most cost-effective antiemetic regimens either fail or are not tolerated.

Antiemetics

Clinical and methodological issues in antiemetic therapy: a worldwide survey of experts' opinions. Multinational Association of Supportive Care in Cancer.

During the 1995 Multinational Association of Supportive Care in Cancer (MASCC) Congress, a consensus conference was planned by the Subcommittee for Antiemetics. To define the topics to be discussed, a questionnaire containing both clinical and methodological issues was sent to 118 experts in 31 countries. The questionnaire contained 33 items on clinical and 19 items on methodological issues, and each response was rated on a 4-level categorical scale. The clinical issues were evaluated for interest, that is clinical importance, and feasibility, that is availability of sufficient data to make them suitable topics for the consensus conference. About 60% of questionnaires were returned, with a small number of missing responses. The responses to the items of clinical interest showed that about two-thirds of the issues identified by the Subcommittee were found by the experts to be of at least high interest, but often the availability of data was found to be insufficient for their discussion. Prevention of acute emesis induced by cisplatin and by moderately emetogenic chemotherapy and the optimal intravenous dose and schedule of the 5-HT3 receptor antagonists were the items with the highest interest and feasibility. The issues in the methodological section were also mostly found to be of at least high interest. The distinction between acute and delayed emesis, the evaluation of the persistence of antiemetic efficacy in subsequent cycles of chemotherapy and the statistical analysis of delayed emesis were the methodological issues in which the highest interest was recorded. Data collected will be used to define the main topics to be discussed during the planned consensus conference.

Antiemetics

5-HT3 receptor antagonists: differences and similarities.

Differences among 5-HT3 receptor antagonists have been reported in pharmacological studies with regard to selectivity of receptor binding, potency, duration of action and dose-response curves. However, whether these pharmacological differences can affect clinical efficacy and safety remains to be determined. A careful analysis of the literature revealed 22 comparative studies among the 5-HT3 receptor antagonists available for review. Unfortunately, several of these trials have some important shortcomings especially in the study design, the size of population studied and the type of anti-emetic treatment selected, making their conclusions often difficult to interpret. However, among these studies, seven large, double-blind clinical trials have clearly shown that the antiemetic activity and tolerability of ondansetron, granisetron, tropisetron and dolasetron is almost identical at least in the prevention of cisplatin-induced emesis. Therefore, from the efficacy and safety point of view, there is no reason to prefer one with respect to the other compound. From the economic perspective, instead, differences may exist and they are strictly related to the dose and schedule of administration chosen for each compound. The information available on the use of 5-HT3 receptor antagonists in the prevention of emesis induced by moderately emetogenic chemotherapy is at best scant. Contrasting results have been reported and only one well-conducted study has been published in full. Therefore, the possible differences among the various compounds are difficult to evaluate. More studies should be carried out in this group of patients.

Antiemetics

[Evaluation of quality of life in oncology. Rationale and objectives of the first phase of the Quality of Life in Oncology project].

Although the subjective nature of quality of life perception is generally accepted, less attention has been paid to the procedure of selecting domains to be explored with questionnaires. In most cases domains are selected by panel of experts. It is not known whether these domains are relevant for the patients. Moreover, questionnaires developed in 'foreign' countries may not be culturally sound or relevant for patients living in different cultural background. In order to explore what really contributes to quality of life of Italian patients, a survey was conducted with the aim of identifying any dimension of quality of life, positively or negatively impacted on from the illness and therapies. A sample of two hundred and eighty eight cancer patients with previously specified characteristics (primary tumor, stage of disease and place of residence) were identified. After consenting to partecipate to the study, a staff member (a physician, a nurse or a psychologist) asked the patient to complete an open-ended questionnaire in the out-patient clinic or at home. This questionnaire, partially derived from a study by Padilla et al. made up of 5 questions: 'What does the term quality of life mean to you?', 'What contributes to a good quality of life?', 'What contributes to a poor or bad quality of life?', 'Which either physical or psychological symptom interferes with your quality of life?', 'State any positive or negative change in your quality of life, due to illness or treatments'. The first question was asked to explore the meaning of quality of life for the patient; the second and third question were asked to determine the contents of quality of life not health related; the fourth question and the diary provided information about quality of life contents related to his own experience of disease. Two hundred and forty eight questionnaires (86.1%) were obtained from 7 Cancer Centres participating to the study (Genova, Milano, Roma, Perugia, Napoli, Cagliari, Palermo). All the questionnaires were transcribed and subsequently broken down in phrases on a form that allowed coding. Three raters (a research nurse, an oncologist and a clinical psychologist) made the content analysis using as conceptual framework the list of domains identified by the Italian Society of Psycho-Oncology. The present study shows the possibility to define the content domain of quality of life attributes for cancer patients, using patients as experts.

Adolescent

Comparative studies of various antiemetic regimens.

Since 1981, when high-dose intravenous metoclopramide was demonstrated to be efficacious, slow but constant improvement in the prevention of chemotherapy-induced emesis has been achieved. Today, a combination of a serotonin receptor 3 (5-HT3) antagonist plus dexamethasone can be considered the most efficacious treatment for the prevention of emesis induced by cisplatin and by moderately emetogenic chemotherapy. Which 5-HT3receptor antagonist should be used? Preclinical differences among 5-HT3receptor antagonists have been reported with regard to selectivity of receptor binding, potency, dose response, and duration of action. Twelve comparative studies among 5-HT3receptor antagonists have been carried out. Unfortunately, all these trials have some important shortcomings (patient population not large enough to show small but clinically important differences; not blinded studies; no association with steroids to maximize treatment efficacy) and, therefore, no definitive conclusions can be drawn. Very recently three large, well-conducted double-blind comparative studies have been published. All three showed that 5-HT3receptor antagonists have almost identical antiemetic efficacy and tolerability. Therefore, the choice among the 5-HT3receptor antagonists should be based only on the acquisition cost of the prescribed dose in each country for each compound.

Antiemetics

Methodology of trials with antiemetics.

Chemotherapy-induced nausea and vomiting can today be controlled with the "new" antiemetics or with their various combinations in a high percentage of patients. Despite this, for some subgroups of patients, certain chemotherapy regimens and some aspects of the phenomenon (delayed presentation), emesis remains a critical problem. Hence, there is the necessity for a continuous effort in the search for new drugs or better treatment modalities and the absolute requisite that these efforts be carried out according to a sound and verified trial methodology. Nausea and vomiting induced by antineoplastic agents are extremely variable phenomena, depending not only on the characteristics of chemotherapy regimens and of the patient population, but also on a subjective feeling generated by the impact of the care system on the patient's individual situation. Therefore, precisely because of this high variability, large comparative trials should be carried out to ensure that the sample is sufficiently representative for the most efficacious antiemetic regimen to be detected. In this field, some of the main problems arising in all clinical trials have their own specificity, particularly the study design, whether completely randomized or cross-over, the follow-up and the importance of prognostic factors. Among these, age, gender and previous chemotherapy with experience of nausea and vomiting have been confirmed as important. In addition, some topics must clearly be highlighted: the definition of the response variables and the assessment of variability of the results obtained with the same antiemetic regimen from one cycle of chemotherapy to the next (i.e. persistence). The greater attention devoted today to delayed emesis raises some methodological questions: this paper suggests some possible solutions for a better evaluation of this phenomenon.

Antiemetics

Antiemetics in cancer chemotherapy: historical perspective and current state of the art.

Chemotherapy-related nausea and vomiting can today be controlled with available antiemetics in a high percentage of patients but emesis remains a problem for some patients, with certain drugs and with repeated cycles of chemotherapy. The fundamental steps of clinical research in antiemetics towards the improvement of the control of nausea and vomiting with new drugs or combinations are presented. Special emphasis is given to cisplatin-induced nausea and vomiting because of the frequency and relevance of this phenomenon. The use of high-dose metoclopramide, its combination with steroids, and later the addition of lorazepam or diphenhydramine represented the evolving standard of the 1980s, with the level of complete protection from vomiting improving from 30%-40% to 60%-70% with the three-drug combination. The introduction of new agents such as the 5-hydroxytryptamine 3 (5-HT3) receptor antagonists has recently offered new possibilities because of their activity and lack of toxicity. In particular, the combination of ondansetron plus dexamethasone is today the most efficacious and least toxic antiemetic treatment for prevention of emesis in patients treated with a single high dose or low repeated doses of cisplatin. A comparison of different 5-HT3 antagonists, always in combination with steroids, is now considered necessary. For patients treated with moderately emetogenic chemotherapy the use of steroids can still be considered the standard treatment. In this setting, the role of 5-HT3 receptor antagonists, alone or in combination with steroids, has to be better defined through large, well-planned clinical trials, which should have a cost-effectiveness analysis as one of their goals.

Antiemetics

Ondansetron.

Ondansetron is the first selective antagonist of the 5-hydroxytryptamine receptors (type 3) marketed for the prevention of emesis induced by antineoplastic agents. Ondansetron has been shown to be more active and less toxic than high-dose metoclopramide in patients submitted to cisplatin chemotherapy. Furthermore, when dexamethasone was added to ondansetron, its antiemetic efficacy increased significantly. In the prevention of emesis induced by a high single dose of cisplatin or by repeated low doses, ondansetron combined with dexamethasone has been shown to be the more efficacious and less toxic antiemetic treatment. However, in the prevention of delayed emesis from cisplatin, its role is still to be defined. In patients submitted to moderately emetogenic chemotherapeutic agents, ondansetron has shown an efficacy superior or equal to standard doses of metoclopramide, but is less toxic. Moreover, when compared with dexamethasone, its antiemetic efficacy and tolerability is similar; in this group of patients ondansetron should be used only when steroids fail. Ondansetron toxicity is generally mild; in particular, it does not induce extrapyramidal reactions. The most frequent side-effects are headache and constipation.

Antineoplastic Combined Chemotherapy Protocols

Reliability and validity of a quality of life questionnaire in cancer patients.

Two studies were sequentially conducted to validate a new questionnaire which takes into consideration the most important variables which could influence quality of life evaluation. Particular attention was given to the methodology employed to collect data and to the patients' characteristics. In the first study 80 consecutive cancer patients were randomised to twice fill in one of four different types of questionnaire, each one characterised by a different polarisation of semantic and syntactic extreme values of the visual linear analogue (for instance, "very much" always on the right, regardless of the semantic value of the answer; positive semantic value always on the right, regardless of whether it was "very much" or "not at all"; and so on). The second study, conducted on 60 lung cancer patients, consisted in testing the reliability (by measuring the reproducibility in different ways) and the validity (by performing a factor analysis) of the type of questionnaire indicated by the first study as the most reliable. The internal coherence was also evaluated by measuring the effects of physical and psychological conditions on the responses.

Adult

Intra and interobserver variability in cancer patients' performance status assessed according to Karnofsky and ECOG scales.

The Karnofsky (K) and ECOG (E) performance status (PS) scales are widely used to evaluate the functional status of cancer patients to determine their eligibility for clinical trials and their prognosis, but knowledge of inter and intraobserver variability of these scales is scarse. We therefore planned a prospective study on 209 consecutive cancer patients to evaluate this critical point. Two independent observers evaluated the KPS and EPS of each patient by interviewing them on the same day. After their interviews the patients were asked to fill in, again on the same day, a self-evaluation scale concerning their ability to perform the routine activities of daily life. The 209 patient self-evaluation scales were presented twice, randomly and blinded, to the two observers who had participated in the evaluation of PS as well as to one other observer who had not. The interobserver correlation for both scales was very high (K = 0.921 for KPS and K = 0.914 for EPS) as was the intraobserver correlation (for KPS: K = 0.993, K = 0.960, and K = 0.959 and, respectively, for EPS: K = 0.982, K = 0.970, and K = 0.920). On the basis of these results, it appears that evaluation of PS made by a clinical oncologist using K or E scales can be very reliable and is a guarantee of optimal selection of cancer patients for inclusion in clinical trials.

Aged

Predictive factors of delayed emesis in cisplatin-treated patients and antiemetic activity and tolerability of metoclopramide or dexamethasone. A randomized single-blind study.

To prevent delayed emesis induced by cisplatin (mean dose 90 mg/m2), 120 consecutive patients were randomized to receive, in a 7-day crossover design, oral metoclopramide (20 mg q.i.d.), dexamethasone (1 mg q.i.d.) or placebo (two tablets q.i.d.) starting 24 hours after the end of chemotherapy. Complete protection from nausea, but not from vomiting. was significantly increased by both dexamethasone and metoclopramide with respect to placebo. Important prognostic factors favoring the appearance of delayed emesis were incomplete protection from vomiting during the first 24 hours after cisplatin, female gender, and highest cisplatin doses. Tolerability of both drugs was good. Larger and randomized controlled trials are necessary to identify better preventive treatment of delayed emesis induced by cisplatin.

Cisplatin

Assessment of nausea.

In a standardized way three different methods of measuring nausea have been assessed in 849 patients enrolled in 4 double blind, randomized, clinical trials, and 2 observational studies. Nausea was measured before and 2, 4, 6, 8 and 24 hours after cancer chemotherapy by using a discrete scale (DS), a visual analogue scale (VAS) and a continuous chromatic analogue scale (ACCS), and it was evaluated according to 4 different dimensions: maximal intensity (MI) entity (E) duration (D) and quantity (Q). The distributions of nausea measurements in the population, agreement between the scales and their sensitivity, and agreement between dimensions and their sensitivity were analyzed. A uniform distribution of nausea measurements was found only in patients receiving chemotherapy without any antiemetic treatment. There was substantial equivalence of the different scales, and no advantage was shown an using an analogue (VAS) than a discrete (DS) scale. A trend toward increasing sensitivity in detecting differences as the dimensions of nausea considered became more inclusive of the various aspects of this symptom (Q more sensible than E more sensible than MI) was observed.

Antiemetics