Antiemetic treatment with oral granisetron in patients receiving moderately emetogenic chemotherapy: a dose-ranging study

[Management of chemotherapy-induced emesis: what is the standard after 20 years of clinical research]

BACKGROUND

The knowledge of the importance, the physiopathological mechanisms, and the management of the chemotherapy-induced emesis has increased exponentially during the last 20 years. High-dosage metoclopramide (MCP) therapy has been introduced in the eighties and serotonine type-3 receptor antagonists (5-HT(3) antagonists) have been used since the late eighties and early nineties. Due to both classes of substances the results of the antiemetic therapies have improved drastically. After 20 years of intensive clinical research it seems to be appropriate to come to an intermediate conclusion.

METHOD

With the aid of an overview and a new analysis of the literature published on this topic so far, the current state of research is shown (including the fields in which further improvement will be necessary), and suggestions are made, wherever it seemed possible, to attain the "gold standard" in antiemetic therapy.

RESULTS AND CONCLUSIONS

In connection with all highly or very highly emetogenic chemotherapies, an antiemetic prophylaxis should be initiated on the day of therapy, especially when using platinum or most of the cyclophosphamide-based regimes for cancer treatment. The recommended prophylaxis consists of a combination of 5-HT(3) antagonists with a corticosteroid. To combat the so-called delayed emesis on the days following therapy, all patients should undergo an oral corticoid therapy, possibly in combination with MCP (especially platinum-therapy patients), less frequently with 5-HT(3) antagonists. With these means of prophylaxis emesis can be prevented/avoided completely in most patients, and nausea can at least be reduced. It is sufficient to administer a single dose of 5-HT(3) antagonists prior to chemotherapy. For ondansetron and granisetron, the best documented substances within this class of drugs, 8 mg (ondansteron) and 3 mg (granisetron) are considered standard dosages. Among the corticoids, most data have been accumulated for dexamethasone. A standard dose of 10 to 20 mg can be administered prior to chemotherapy. Right after and especially on the days following chemotherapy higher dosages seem to be indicated.

PROSPECT

Further therapy improvements, especially concerning emesis and nausea on the days following chemotherapy, are necessary and are currently object of clinical research.

5-hydroxytryptamine type-3 receptor antagonists for chemotherapy-induced and radiotherapy-induced nausea and emesis: can we safely reduce the dose of administered agents?

BACKGROUND

Nausea and emesis as a consequence of chemotherapy or radiotherapy can have an adverse effect on patients' quality of life during cancer treatment and may last for > 5 days after administration. Guidelines suggest that, used at appropriate doses, the 5-hydroxytryptamine type-3 (5-HT3) receptor antagonists--which are considered the antiemetic "gold standard" when they are administered in combination with corticosteroids--demonstrate equivalent efficacy and safety. However, due to financial considerations, these agents often are used at lower doses than recommended.

METHODS

A literature review of relevant publications pertaining to the control of chemotherapy-induced nausea and emesis and dosing issues of the 5-HT3 receptor antagonists was undertaken to provide a comprehensive review of dosing issues relevant to the 5-HT3 receptor antagonists.

RESULTS

The issue of "down dosing" was particularly pertinent because of the nature of the 5-HT3 receptor antagonist dose-response curve: A steep dose-response profile within a narrow dose range suggests that antiemetic control will be lost suddenly after dose deescalation. However, the array of predisposing and confounding patient factors indicates that it is unlikely that a loss of antiemetic control will be apparent across a population; rather, individuals will experience loss of control as the dose is reduced below threshold. Of the 4 5-HT3 receptor antagonists currently licensed in the United States (granisetron, ondansetron, dolasetron, and palonosetron), ondansetron is used sometimes at lower than optimal doses, and there is evidence to suggest that even the approved oral dose of dolasetron may be suboptimal.

CONCLUSIONS

Suboptimal dosing not only will be detrimental to patients' quality of life but, ultimately, will prove counterproductive in terms of hospital resources, and it will add to the already significant socioeconomic burden associated with cancer therapy. Therefore, the dose of antiemetic agent administered should be sufficiently high to ensure good emesis control across the whole patient population.

Granisetron: An Update on its Clinical Use in the Management of Nausea and Vomiting

Nausea and vomiting are typical side effects of cytotoxic therapy and some surgical procedures. These symptoms can represent a major therapeutic challenge and, if inadequately controlled by antiemetic treatment, will result in increased mortality, morbidity, and health care costs. However, the management of nausea and vomiting has improved greatly in recent years following the introduction of the 5-HT3-receptor antagonists, known as 'setrons.' In light of recent developments in antiemetic care, including the approval of the first neurokinin-1-receptor antagonist aprepitant (Emend; Merck and Company, Inc.; West Point, PA) and a new 5-HT3 receptor antagonist palonosetron (Aloxi; MGI Pharma; Minneapolis, MN), this article provides an update on the clinical experience gained with the 5-HT3-receptor antagonist granisetron (Kytril; Roche Laboratories, Inc.; Nutley, NJ) for the management of chemotherapy-induced, radiation-induced, and postoperative nausea and vomiting, and also reviews its use in special patient populations. Granisetron is a potent and highly selective 5-HT3-receptor antagonist that has little or no affinity for other receptors, a characteristic that is thought to underlie the favorable side-effect and safety profiles of this agent. Extensive clinical trial data have shown granisetron to be an effective and well-tolerated agent for the treatment of nausea and vomiting in the oncology and surgical settings. Granisetron has also been shown to be effective and well tolerated in special populations, such as patients refractory to antiemetic treatment, patients with hepatic or renal impairment, and children. Data also suggest that its safety profile and minimal potential for drug-drug interactions would make it an antiemetic agent of choice for elderly cancer patients.

Chemotherapy-induced nausea and vomiting: the importance of acute antiemetic control

Nausea and vomiting are two of the most feared side effects of cancer chemotherapy and radiotherapy. Chemotherapy-induced nausea and vomiting can be broadly categorized as acute (occurring within 24 hours of therapy), delayed (persisting for 6-7 days after therapy), or anticipatory (occurring prior to chemotherapy administration). Breakthrough and refractory nausea and vomiting describe the symptoms of uncontrolled emesis. Evidence suggests that good control of nausea and vomiting during the acute period correlates with the control of delayed emesis. Conversely, protection failure during the first 24 hours has a high predictive value for delayed emesis in the same cycle. The 5-HT(3)-receptor antagonists, regarded as the 'gold standard' in antiemetic therapy, are the first-line treatment for moderately and highly emetogenic chemotherapy and radiotherapy regimens in adults and children. Evidence suggests that the 5-HT(3)-receptor antagonists administered in combination with corticosteroids afford the best protection from symptoms of acute emesis and, by extrapolation, the most effective prevention of delayed emesis. Antiemetic therapeutic guidelines stress that the goal of therapy is to prevent cytostatic-induced nausea and vomiting. Therefore, the prophylactic use of the most effective antiemetic regimen-taking into consideration the emetogenicity of the chemotherapy and individual patient characteristics-must be adhered to in order to prevent acute, delayed, and anticipatory nausea and vomiting.

Evaluation of outcomes in converting from intravenous ondansetron to oral granisetron: an observational study

OBJECTIVE

To describe a systematic evaluation of the outcomes associated with revising institutional guidelines for the prevention of acute chemotherapy-induced nausea and vomiting (CINV) to promote cost-effective use of the serotonin (5-HT3) antagonists.

METHODS

The 5-HT3 antagonist of choice in the antiemetic guidelines was revised from intravenous ondansetron to oral granisetron in August 1995. Patient assessments were conducted immediately prior to (Period 1) and after (Period 2) guideline revision using validated questionnaires. The effectiveness of the two 5-HT3 antagonists were compared and reported to the prescribing oncologists. Outcomes were assessed one year after guideline revision (Period 3) using identical methods.

RESULTS

No difference was found in the rate of total control (no emesis, no nausea) between patients receiving oral granisetron (60%) and intravenous ondansetron (56%) (p = 0.408, Period 1 vs. 2). Nausea severity, the number of emesis episodes, and use of rescue antiemetics were also equivalent. Prescriber compliance with using the 5-HT3 antagonist of choice and dose increased from 48% to 61% following adoption of oral granisetron. By Period 3, compliance increased to 78%, and satisfactory control of acute CINV was again documented. The costs for prevention of acute CINV decreased from $107 in Period 1 (intravenous ondansetron only) to $65 in Period 3 (oral granisetron).

CONCLUSIONS

Outcomes associated with use of oral granisetron and intravenous ondansetron were equivalent in this patient population. Guideline revision and outcome documentation by the oncology pharmacists resulted in increased compliance with institution guidelines and a 40% cost savings.

Stratified administration of serotonin 5-HT3 receptor antagonists (setrons) for chemotherapy-induced emesis. Economic implications

The serotonin 5-HT3 receptor antagonists or 'setrons' have become the standard of care for the prevention of chemotherapy-induced emesis (CIE) and are first-line therapy for acute CIE in healthcare organisations worldwide. However, their superior efficacy versus standard antiemetics comes at a significant cost. Currently, 3 agents are available in the US: ondansetron, granisetron and dolasetron. The most important treatment-related factor contributing to CIE is the emetogenicity of chemotherapy. The ability to customise, or stratify, the setron dose to match the emetogenic challenge of the chemotherapy administered has potential benefits, both clinically and economically. In adults, there is an appreciable amount of clinical literature addressing stratified administration; however, the amount of 'hard' economic data is rather limited. Intuitively, if clinical outcomes are equivalent, then stratified administration should be associated with economic benefits, as it generally promotes the use of doses lower than those recommended by the manufacturer. The literature strongly substantiates this for ondansetron, but is not as favourable for granisetron or dolasetron. As the rationale and justification for dose stratification is contained in the clinical literature, the authors have reviewed the pertinent literature supporting the clinical and economic benefits of dose stratification in both adult and paediatric patients. The authors also provide a discussion of various additional strategies that can be employed to ensure the appropriate and cost-effective use of setrons in real-world practice settings. These strategies include the use of lower doses than recommended by manufacturers, use for acute versus delayed phase emesis, enhancing the antiemetic efficacy by the addition of a corticosteroid, use of oral versus injectable formulations (when appropriate) and the implementation and use of local, national and international drug use guidelines.

Randomized, multicenter comparison of oral granisetron and oral ondansetron for emetogenic chemotherapy

STUDY OBJECTIVES

To compare the antiemetic effectiveness and safety of oral granisetron plus dexamethasone with those of oral ondansetron plus dexamethasone administered before emetogenic chemotherapy.

DESIGN

Randomized, prospective, multicenter, open-label study.

SETTINGS

University-teaching hospital and veterans health care system.

PATIENTS

Sixty-one chemotherapy-naïve patients scheduled to receive emetogenic antineoplastic agents.

INTERVENTION

A single-dose oral granisetron 1 mg and dexamethasone 12 mg or single-dose oral ondansetron 16 mg and dexamethasone 12 mg was administered before chemotherapy.

MEASUREMENTS AND RESULTS

Twenty-four hours after administration patients were contacted to assess nausea, emesis, and adverse events. There were no statistical differences in frequency of nausea or emesis between groups. Seventy-six percent and 82% of patients receiving ondansetron and granisetron, respectively, experienced no emesis 24 hours after chemotherapy. Complete protection from nausea occurred in 58% and 46% of patients receiving the drugs, respectively. Adverse events were similar between groups.

CONCLUSION

Oral granisetron 1 mg and ondansetron 16 mg plus dexamethasone are safe and effective in preventing nausea and vomiting related to emetogenic chemotherapy.

Advances in use of the 5-HT3 receptor antagonists

Nausea and vomiting continue to rank as important side effects for cancer patients receiving chemotherapy. The class of drugs known as the 5-HT3 receptor antagonists have become widely used for chemotherapy-induced nausea and vomiting, and are considered a standard part of care for moderately- and highly-emetogenic chemotherapy in combination with corticosteroids. Ondansetron (Zofran, Glaxo Wellcome), granisetron (Kytril, SmithKline Beecham) and dolasetron (Anzemet, Hoechst Marion Roussel) are commercially available in the US. Intravenous forms of all three drugs have demonstrated efficacy in preventing acute (< or = 24 h following chemotherapy) nausea and emesis due to moderately- and highly-emetogenic chemotherapy. Oral forms of the drugs have been shown to be effective in prevention of nausea and emesis due to moderately-emetogenic chemotherapy. More recently, oral 5-HT3 receptor antagonists have demonstrated efficacy in the prevention of nausea and vomiting due to highly-emetogenic chemotherapy as well. Comparative trials between the three agents have shown no clinically important differences in outcome and they should be considered clinically equivalent. Optimal oral anti-emetic regimens for high-dose chemotherapy with bone marrow or stem cell transplantation remain to be determined and future oral studies should target this population. In general, the decision of which 5-HT3 receptor antagonist to select for formulary inclusion should be based on the dose of anti-emetic used and the acquisition cost of the agents being compared. The oral route should be used whenever possible.

5-HT3 antiemetic therapy for patients with breast cancer

Antiemetic treatment should be considered for breast cancer patients receiving moderately emetogenic chemotherapy. Although the extent of chemotherapy-induced emesis is largely dependent on the emetogenic potential of the specific agents employed, patient characteristics such as age and sex also contribute. Recent clinical studies show that treatment with the currently available 5-HT3 antagonists effectively reduces the incidence of chemotherapy-induced nausea and vomiting and improves quality of life in a substantial number of these patients. A Medline search from 1994 through February 1998 identified clinical trials that included previously untreated breast cancer patients using antiemetic therapy such as granisetron, ondansetron, dolasetron, and metoclopramide. The studies reviewed here indicate that the antiemetic efficacy of 5-HT3 antagonists is equivalent in previously untreated patients receiving moderately emetogenic chemotherapy for breast cancer, depending on the doses and schedules utilized. In particular, two comparative studies of granisetron and ondansetron with specific data for breast cancer patients showed that both agents eliminate nausea in approximately 50%, and vomiting in 60-70% of these patients, with the higher values observed when steroids were added to the 5-HT3 receptor antagonist regimen. Although the chemotherapy regimens employed for breast cancer are considered only moderately emetogenic, these regimens account for 60-90% of patients experiencing nausea and vomiting. The most recent clinical studies demonstrate that 5-HT3 antagonists can significantly reduce the incidence of nausea in breast cancer patients receiving moderately emetogenic chemotherapy and should be employed in this setting.

A double-blind comparison of the efficacy of two dose regimens of oral granisetron in preventing acute emesis in patients receiving moderately emetogenic chemotherapy

BACKGROUND

The purpose of this study was to define an optimal administration schedule of granisetron for patients receiving moderately emetogenic chemotherapy by comparing the antiemetic efficacy and safety of 2 mg of the drug administrated orally.

METHODS

In this double-blind, randomized, parallel study, 2-dose regimens of oral granisetron were evaluated in 697 adult cancer patients. Patients were stratified by gender and randomized to receive 2 mg oral granisetron, either as a divided dose given 1 hour prior to chemotherapy and 12 hours after the start of chemotherapy, or as a single dose 1 hour prior to chemotherapy at Cycle 1. The primary efficacy endpoints assessed were the percentage of patients with complete response (no nausea, no emesis, and no additional antiemetic medication during the 24-hour post-chemotherapy interval) and the incidence of emesis and nausea. Following completion of Cycle 1, patients were given the opportunity to receive open-label granisetron (2 mg once daily) on the first day of each remaining cycle of chemotherapy.

RESULTS

No statistically significant differences in any of the endpoints were observed between the two treatment groups. Approximately 50% of patients in both treatment groups achieved complete response. The proportion of patients with no episodes of emesis occurred with similar frequency in the two treatment groups. Approximately 52% of patients in either treatment group were free of nausea during the postchemotherapy period. There was no difference between treatment groups regarding the use of antiemetic rescue medication. Finally, the incidence of adverse experiences was similar for both treatment groups.

CONCLUSIONS

Both dose regimens of oral granisetron were similarly effective in controlling nausea and vomiting in the 24-hour interval following chemotherapy. Granisetron was well tolerated with few adverse events attributable to the study drug.

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.

Granisetron: the second serotonin-receptor antagonist

OBJECTIVE

To review the pharmacology, pharmacokinetics, clinical efficacy, and adverse effects of granisetron, focusing on critical analysis of published clinical trials and comparison with other antiemetic agents, including ondansetron.

DATA SOURCES

MEDLINE (1966-1995) and CANCERLIT (1991-1995) searches of English-language literature using the terms "granisetron" and "granisetron (rn)" were performed.

STUDY SELECTION AND DATA EXTRACTION

All articles were considered for possible inclusion in this review. Abstracts of clinical trials were included only when they were judged to add critical information not otherwise available in the medical literature. For studies published more than once, the most recent publication was cited.

DATA SYNTHESIS

Nausea and vomiting are rated by patients as the most distressing chemotherapy-related adverse effects and may produce potentially life-threatening complications. The discovery of the role of serotonin in nausea and vomiting and the development of selective serotonin3-receptor (5-HT3) antagonists has significantly diminished the incidence and consequences of chemotherapy-related nausea and vomiting. Granisetron is the second 5-HT3-receptor antagonist to be marketed in the US. Granisetron has been compared with other antiemetic agents, including ondansetron, against highly and moderately emetogenic chemotherapy. The results of these trials have shown granisetron to be superior to conventional antiemetics and as effective as ondansetron in the prevention of chemotherapy-induced nausea and vomiting. The optimal dose of granisetron has yet to be determined. Formulary decisions should be based on a cost comparison among the 5-HT3-receptor antagonists at individual institutions.

CONCLUSIONS

Granisetron is a safe, effective antiemetic agent for the management of nausea and vomiting caused by cancer chemotherapy.