Controlling emesis related to cancer therapy

Involving women with breast cancer in the development of a patient information leaflet for anticipatory nausea and vomiting

As chemotherapy regimens increase in toxicity and changes in service provision move towards a more ambulatory outpatient basis, patients are often coping with side effects of treatment in isolation. Despite advances in pharmacological control, for some patients nausea and vomiting can be problematic. For some this can develop into anticipatory nausea and vomiting (ANV), which can severely effect the patients physical and psychological well-being. It is well recognised that the giving of realistic and understandable information is paramount to empower patients in their individual coping. A plethora of literature supports the use of Patient Information Leaflets as a means to educate and empower patients within their treatment trajectory. This paper discusses the authors' experiences in developing a Patient Information Leaflet, designed to assist breast cancer patients in understanding and coping with the symptoms of ANV. The patient's needs were sought to add clarity to the development and design of the leaflet. The authors conclude that developing a Patient Information Leaflet was a major undertaking in terms of time and resources.

Chemotherapy-related nausea and vomiting - past reflections, present practice and future management

Although much progress has occurred in the last decade regarding the management of chemotherapy-induced nausea and vomiting, these remain among the most intolerable side-effects of treatment and patients continue to report the negative impact such symptoms have on their ability to enjoy life. Inadequate control of nausea and vomiting reduces patients' quality of life and functional status and jeopardizes the delivery of optimal treatment, so making its management a priority for oncology health care workers. This article will reflect on past and present evidence regarding the management of chemotherapy-induced nausea and vomiting while highlighting some of the most recent scientific advances before drawing conclusions about the future management of this troublesome symptom for patients receiving chemotherapy.

Platinum-based chemotherapy in metastatic breast cancer: current status

Cisplatin and carboplatin are active in previously untreated patients with metastatic breast cancer (MBC) with mean response rates (RRs) of 50 and 32%, respectively. In pretreated patients the RR to cisplatin/carboplatin monotherapy declines markedly to <10%. Cisplatin and carboplatin have been combined with many other cytotoxics. In first-line setting high activity has been observed in combination with taxanes or vinorelbine (RRs consistently approximately 60%). It appears that these newer combinations are superior to older regimens with etoposide (RRs 30 to 50%) or 5-fluorouracil (RRs 40 to 60%). Cisplatin-/carboplatin-based regimens with infusional 5-FU and epirubicin/paclitaxel/vinorelbine achieve high RRs of around 60 to 80%. However these regimens are difficult to administer in all patients because they require central venous access for continuous 5-FU infusion. In pretreated MBC the combinations of cisplatin-taxane/vinorelbine/gemcitabine or carboplatin-docetaxel/vinorelbine yield RRs of 40 to 50%, which are higher than those achieved with platinum-etoposide/5-FU. In locally advanced disease cisplatin-based regimens achieve very high RRs (>80%). This would suggest that in chemotherapy-naïve patients platinum-based therapy might have an important role to play. Additionally the synergy demonstrated between platinum compounds, taxanes and herceptin, in preclinical and clinical studies is of immense importance and the results of the two ongoing Breast Cancer International Research Group randomized phase III studies are eagerly awaited. These studies may help clarify the role of platinum compounds in the treatment of metastatic and possibly early breast cancer.

Open probability of homomeric murine 5-HT3A serotonin receptors depends on subunit occupancy

1. The time course of macroscopic current responses of homomeric murine serotonin 5-HT3A receptors was studied in whole cells and excised membrane patches under voltage clamp in response to rapid application of serotonin. 2. Serotonin activated whole cell currents with an EC(50) value for the peak response of 2 microM and a Hill slope of 3.0 (n = 12), suggesting that the binding of at least three agonist molecules is required to open the channel. 3. Homomeric 5-HT3A receptors in excised membrane patches had a slow activation time course (mean +/- S.E.M. 10-90 % rise time 12.5 +/- 1.6 ms; n = 9 patches) for 100 microM serotonin. The apparent activation rate was estimated by fitting an exponential function to the rising phase of responses to supramaximal serotonin to be 136 s(-1). 4. The 5-HT3A receptor response to 100 microM serotonin in outside-out patches (n = 19) and whole cells (n = 41) desensitized with a variable rate that accelerated throughout the experiment. The time course for desensitization was described by two exponential components (for patches tau(slow) 1006 +/- 139 ms, amplitude 31 %; tau(fast) 176 +/- 25 ms, amplitude 69 %). 5. Deactivation of the response following serotonin removal from excised membrane patches (n = 8) and whole cells (n = 29) was described by a dual exponential time course with time constants similar to those for desensitization (for patches tau(slow) 838 +/- 217 ms, 55 % amplitude; tau(fast) 213 +/- 44 ms, 45 % amplitude). 6. In most patches (6 of 8), the deactivation time course in response to a brief 1-5 ms pulse of serotonin was similar to or slower than desensitization. This suggests that the continued presence of agonist can induce desensitization with a similar or more rapid time course than agonist unbinding. The difference between the time course for deactivation and desensitization was voltage independent over the range -100 to -40 mV in patches (n = 4) and -100 to +50 mV in whole cells (n = 4), suggesting desensitization of these receptors in the presence of serotonin does not reflect a voltage-dependent block of the channel by agonist. 7. Simultaneously fitting the macroscopic 5-HT3A receptor responses in patches to submaximal (2 microM) and maximal (100 microM) concentrations of serotonin to a variety of state models suggests that homomeric 5-HT3A receptors require the binding of three agonists to open and possess a peak open probability greater than 0.8. Our modelling also suggests that channel open probability varies with the number of serotonin molecules bound to the receptor, with a reduced open probability for fully liganded receptors. Increasing the desensitization rate constants in this model can generate desensitization that is more rapid than deactivation, as observed in a subpopulation of our patches.

Granisetron compared with prednisolone plus metopimazine as anti-emetic prophylaxis during multiple cycles of moderately emetogenic chemotherapy

This randomized, double-blind, double-dummy parallel study compared the anti-emetic efficacy and tolerability of the serotonin antagonist granisetron with prednisolone plus the dopamine D2 antagonist metopimazine during nine cycles of moderately emetogenic chemotherapy. Chemotherapy naive women with stage I or II breast cancer scheduled to intravenous cyclophosphamide, fluorouracil and methotrexate or cyclophosphamide, epirubicin and fluorouracil every 3 weeks were included. Patients received a single intravenous dose of granisetron 3 mg or a 3-day oral treatment with prednisolone 25 mg once a day plus metopimazine 30 mg four times a day. A total of 223 women were enrolled and 218 patients (97.8%) were evaluable for efficacy. Granisetron (n = 109) was superior to prednisolone plus metopimazine (n = 109) in the prophylaxis of acute nausea and vomiting during the first cycle of chemotherapy (P < 0.001) and prednisolone plus metopimazine was superior on days 2-5 (P = 0.002). Overall, granisetron was superior on days 1-5 (P = 0.009). The median number of cycles completed with granisetron was five (95% confidence interval 4-6) compared with two (95% confidence interval 2-2) for prednisolone plus metopimazine (P = 0.0019). Constipation and rash were reported more frequently with granisetron (P < 0.001 and P = 0.043 respectively) and palpitations more frequently with prednisolone plus metopimazine (P = 0.015). In conclusion, the number of cycles completed with granisetron was significantly higher than the number completed with prednisolone plus metopimazine, but the anti-emetic efficacy of both treatments declined during multiple cycles of moderately emetogenic chemotherapy.

A risk-benefit assessment of serotonin 5-HT3 receptor antagonists in antineoplastic therapy-induced emesis

Insight into the pathophysiology of antineoplastic therapy-induced nausea and vomiting led to the development of the serotonin 5-HT3 receptor antagonists as the most potent class of antiemetic agents. Among those which have been investigated are ondansetron, granisetron, tropisetron and dolasetron. A risk-benefit analysis of these drugs must not only account for the modest clinical differences in efficacy and tolerability, but also should include such issues as ease of use, route of administration, dosage considerations and patient preference. Pharmacokinetic and preclinical studies reveal distinctions among these antiemetics, but, overall, these distinctions do not translate in to clinically significant differences. In clinical trials, the most widely studied members of the 5-HT3 receptor antagonists are granisetron and ondansetron, which have been found to possess equivalent antiemetic efficacy. Dolasetron and tropisetron are also available, and some randomised trials have also documented their similar antiemetic activity, depending on the doses and schedules used. The equivalent efficacy of oral granisetron 2 mg versus intravenous ondansetron 32 mg has recently been demonstrated in prospective randomised clinical trials in patients receiving either highly emetogenic or moderately emetogenic antineoplastic therapy. The utilisation and efficacy of oral ondansetron and dolasetron in patients receiving moderately emetogenic antineoplastic therapy has also been documented. This review offers a brief overview of the pharmacokinetic and preclinical research on the 5-HT3 antagonists, a review of the comparative clinical trials of the major members of this class and a summary risk-benefit assessment that considers clinical applicability and cost, as well as efficacy and safety.

Comparative efficacy of oral and intravenous granisetron for the prevention of acute chemotherapy-induced emesis

Intravenous 5-hydroxytryptamine3 (5-HT3) receptor antagonists are now established antiemetics in the treatment of chemotherapy-induced emesis. For optimal convenience and acceptability, oral therapy is desirable. Retrospective comparisons indicate that oral granisetron may have an efficacy comparable with that of intravenous granisetron. Recent new data are available on the use of granisetron in the prophylaxis of acute emesis in randomized, double-masked trials. After moderately emetogenic chemotherapy, the optimal regimen appears to be 1 mg twice daily, although 2 mg once daily is equally effective. Oral granisetron is significantly superior to oral prochlorperazine. After high-dose cisplatin chemotherapy, oral granisetron is as effective as metoclopramide plus dexamethasone; the addition of dexamethasone further enhances its efficacy. Oral granisetron was well tolerated in all these trials. Headache and constipation were the most common adverse events, as has been reported for other 5-HT3 receptor antagonists. No randomized trials of oral-only tropisetron or dolasetron have yet been published.

Constipation and diarrhea: the neglected symptoms

OBJECTIVE

To review the symptom experience of constipation and diarrhea related to cancer and its treatment.

DATA SOURCES

Published articles and book chapters relating to constipation and diarrhea in patients with cancer.

CONCLUSIONS

Constipation and diarrhea often represent a major concern and source of discomfort for the cancer patients. Research is needed to establish prevention and treatment protocols for patients at risk for constipation or diarrhea.

IMPLICATIONS FOR NURSING PRACTICE

Oncology nurses are in an excellent position to recognize individuals who are at high risk for constipation and diarrhea. Preventive strategies and treatment protocols are of utmost importance.

Progress in reducing nausea and emesis. Comparisons of ondansetron (Zofran), granisetron (Kytril), and tropisetron (Navoban)

BACKGROUND

Nausea and vomiting are the most distressing side effects associated with the administration of chemotherapy for neoplastic diseases. Nausea, in particular, often had been ignored in studies of chemotherapy side effects. Recently, progress has been made in the control of chemotherapy-induced nausea and vomiting, due, in part, to a better understanding of the physiologic mechanisms involved.

METHODS

This paper reviews recent advances in the control of emesis, focusing on pharmacologic treatments.

RESULTS

The efficacy and safety of the serotonin (5-HT3) receptor antagonists granisetron, ondansetron, and tropisetron in the control of acute and delayed emesis and emesis induced by repeat-cycle chemotherapy are summarized. Although differences in study design and definitions of response criteria have made it difficult to compare the studies that have evaluated these three agents, the overall body of literature supports several clinical findings.

CONCLUSIONS

(1) The 5HT3 antiemetic agents have been shown to be clinically more effective in the control of nausea and emesis than previously used agents. (2) No one of the three has demonstrated consistently greater efficacy. (3) Efficacy appears to be more pronounced for cisplatin-containing regimens than for moderate or less emetogenic chemotherapy regimens. (4) Effectiveness of the 5HT3 agents appears to be less for delayed nausea and emesis than for acute symptoms. Potential control of anticipatory nausea and emesis has not been investigated. (5) Control over nausea appears to be significantly less than control over emesis. In the studies in which it has been measured, nausea control remains incomplete for approximately half the patients given 5HT3 agents. (6) The efficacy of the agents appears to diminish across repeated days and, perhaps, across repeated chemotherapy cycles. (7) The addition of a steroid such as dexamethasone increases the efficacy of both 5HT3 and other antiemetic agents. This effect also seems to apply to delayed nausea and emesis.

Oral granisetron alone and in combination with dexamethasone: a double-blind randomized comparison against high-dose metoclopramide plus dexamethasone in prevention of cisplatin-induced emesis. The Granisetron Study Group

PATIENTS AND METHODS

Three anti-emetic treatment regimens were compared in 357 patients receiving cisplatin therapy (mean dose 81 mg/m2) in this double-blind randomized study. Regimens studied were i) granisetron 1 mg bd orally for 7 days (granisetron alone); ii) gran 1 mg bd orally for 7 days plus prophylactic dexamethasone (12 mg i.v.) on the first day only (gran/dex); iii) metoclopramide (3 mg/kg i.v. loading dose; 4 mg/kg i.v. infusion) plus dex (12 mg i.v.) on the first day followed by met 10 mg orally tds for a further 6 days (met/dex).

RESULTS

At 24 hours, gran/dex was significantly superior to met/dex in terms of total anti-emetic control, defined as no nausea, no vomiting, no rescue anti-emetic therapy, not withdrawn (54.7% gran/dex vs. 37.2% met/dex; P < 0.01). There was also a significant delay in time to onset of nausea (P < 0.01) and vomiting (P < 0.01) following gran/dex compared with met/dex. Oral granisetron alone was as effective as met/dex in control of acute emesis in all parameters examined. There were no significant differences between the three groups in the control of delayed nausea and vomiting. The most common adverse experiences in both granisetron groups were headache and constipation, both characteristic of 5-HT3 antagonists. Agitation, somnolence, diarrhoea and decreased appetite were reported more frequently by the met/dex group.

CONCLUSIONS

Oral granisetron as a single agent is as effective as high doses of i.v. met/dex in preventing cisplatin-induced emesis. Oral granisetron in combination with a corticosteroid provides superior anti-emetic control to the met/dex regimen in patients undergoing highly emetogenic chemotherapy.

A dose-finding study of granisetron, a novel antiemetic, in patients receiving high-dose cisplatin. Granisetron Study Group

In this double-blind study, the efficacy and safety of a single intravenous dose of a novel antiemetic, granisetron, was assessed at two dose levels (40 micrograms/kg and 160 micrograms/kg). A group of 355 patients were given prophylactic granisetron prior to receiving high-dose cisplatin chemotherapy. In the first 24 h, 57% and 59% of patients, respectively, experienced no vomiting and no more than mild nausea. Two further doses of granisetron (40 micrograms/kg) were permitted in the first 24 h to treat any emergent symptoms of nausea and vomiting; 66 patients (39%) in the 40-micrograms/kg treatment group and 56 patients (34%) in the 160-micrograms/kg group received at least one additional dose. Additional treatment with granisetron resulted in resolution or improvement of symptoms in at least 73% of these patients. Over the 7-day study period, 52% of patients in the lower-dose group and 48% in the higher required no further conventional antiemetic therapy. The two different dose levels were equal both in terms in efficacy and safety. Granisetron was well tolerated throughout the dose range of the study [40-240 micrograms kg-1 (24 h)-1]. The commonest adverse event was headache, seen in 14%-16% of patients. In all but one case this resolved spontaneously or responded to simple treatment.

Early clinical trial of MDL 73.147 EF: a new 5-HT3-receptors antagonist for the prevention of chemotherapy-induced nausea and vomiting

BACKGROUND

Like MDL 72.222, one of the first selective 5-hydroxytryptamine3 (5-HT3) receptors antagonist discovered, MDL 73.147 EF has been shown to possess antiemetic properties in the ferret model. We conducted a phase I study with MDL 73.147 EF in 31 patients, treated with emetogenic drugs over one to five days (cisplatin, cyclophosphamide, doxorubicin, dacarbazine).

PATIENTS AND METHODS

5 groups of at least 5 patients received rising unit doses of MDL 73.147 EF (10 to 50 mg) intravenously before chemotherapy, with two more doses per day if needed. Nausea was assessed by a patient-completed visual analogue scale and episodes of vomiting recorded by an independent observer.

RESULTS

51.6% of the patients were complete responders on day one and 40% on days two to five. One patient was given other rescue antiemetic therapy. Adverse events included constipation (25.8%), mildly elevated blood pressure (12.9%) and other minor events. No extrapyramidal effects have been reported. There was no suggestion of dose-dependent efficacy at the dose levels studied in this limited set of patients.

CONCLUSIONS

We conclude that MDL 73.147 EF is a well tolerated and possibly effective antiemetic.

Cisplatinum based chemotherapy: role of the antiserotoninergic ondansetron in prevention of emesis

Serotonin is a neurotransmitter involved in chemotherapy-induced emesis and ondansetron is a new drug endowed with selective antagonism against the 5HT3 receptors. Phase I-II studies have demonstrated its activity against acute emesis after single-dose cisplatin, reporting particularly low toxicity; in comparative studies with high-dose metoclopramide, it has been proved to be more effective and completely devoid of extrapyramidal side effects. Ondansetron has shown its activity and safety also in multiple-day cisplatin regimens. Its antiemetic efficacy is improved by the addition of dexamethasone. Preliminary data suggest its role also when used in single-dose administration. Its activity in the delayed phase of cisplatin emesis needs to be further explored.

Randomised study of two doses of cisplatin with cyclophosphamide in epithelial ovarian cancer

Cisplatin is generally accepted to be the most active cytotoxic agent for the treatment of ovarian cancer but the optimum dose remains unclear. We have performed a randomised trial to assess the importance of cisplatin dose in the treatment of advanced epithelial ovarian cancer. Patients were randomly assigned treatment with 50 mg/m2 (low dose) or 100 mg/m2 (high dose) cisplatin plus 750 mg/m2 cyclophosphamide, for a maximum of six cycles with intervals of 3 weeks. We planned to recruit 300 patients, but an interim analysis on the first 165 indicated a highly significant survival difference (p = 0.0008). Recruitment was therefore stopped and the trial patients were followed-up for 12 months longer. The relative progression rate (high-dose/low-dose) after 12 months' extra follow-up was 0.55 (95% confidence interval 0.37-0.81, p = 0.003) and the relative death rate 0.53 (0.34-0.81, p = 0.003). Overall median survival was 69 weeks in the low-dose group and 114 weeks in the high-dose group. Residual disease extent before chemotherapy had an important influence--patients with lesions of less than 2 cm did best; if given high-dose cisplatin their median survival was 3 years. 56 low-dose and 45 high-dose patients completed six cycles of chemotherapy; 15 and 9 patients, respectively, were withdrawn early because of progressive disease and treatment was stopped in 6 and 25, respectively, because of unacceptable side-effects or patient refusal. Toxic effects were significantly greater in the high-dose group, especially those on the nervous system and ears, alopecia, vomiting, and anaemia. Although the higher dose of cisplatin clearly leads to better results in terms of survival, its overall clinical benefit in the management of ovarian cancer will depend on further improvements in measures to alleviate toxic effects.